NXP Laboratories UK JN5142M3, JN5142M0 Datasheet

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Data Sheet: JN5142

IEEE802.15.4 Wireless Microcontroller

Overview

Features: Transceiver

 2.4GHz IEEE802.15.4 compliant  128-bit AES security processor  MAC accelerator with packet

formatting, CRCs, address check, auto-acks, timers

 Integrated ultra low power sleep

oscillator – 0.5µA

 2.0V to 3.6V battery operation  Deep sleep current 0.12µA

(Wake-up from IO)

 0.5µA sleep with timer (1.5uA with

RAM held)

 <$0.50 external component cost  Rx current 16.5mA  Tx current 14.8mA  Receiver sensitivity -95dBm

 Transmit power 2.5dBm

Features: Microcontroller

 32-bit RISC CPU, 1 to 32MHz

clock speed

 Low power operation  Variable instruction width for high

coding efficiency

 Multi-stage instruction pipeline  128KB ROM and 32KB RAM for

bootloaded program code

 RF4CE or JenNet-IP software in

ROM

 Master/Slave I2C interface.  3xPWM and Application

timer/counter

 UART  SPI port with 3 selects  Supply Voltage Monitor with 8

programmable thresholds

 2- to 4-input 8-bit ADC,

comparator

 Battery and temperature sensors  Watchdog timer and Power-on-

Reset (with brown-out) circuit

 Up to 18 DIO

Industrial temp -40°C to +125°C 6x6mm 40-lead Punched QFN

Lead-free and RoHS compliant

The JN5142 is an ultra low power, high performance wireless microcontroller suitable for Remote Control, IEEE802.15.4 and Active RFID applications. There is also a ROM variant that supports JenNet-IP Smart Devices. The JN5142 features an enhanced 32-bit RISC processor offering high coding efficiency through variable width instructions, a multi-stage instruction pipeline and low power operation with programmable clock speeds. It also includes a 2.4GHz IEEE802.15.4 compliant transceiver, 128KB of ROM, 32KB of RAM, and a comprehensive mix of analogue and digital peripherals. The operating current is below 18mA, allowing operation direct from a coin cell.

The peripherals support a wide range of applications. They include a 2-wire serial interface, which operates as either master or slave, a two channel ADC with battery and temperature sensors. A large switch matrix of up to 81 elements can be supported for remote control applications. The best in class radio current and a 0.5µA sleep timer give excellent battery life.

Block Diagram

32-bit

RISC CPU

Timer

UART

4-Chan 8-bit

ADC

Battery and,

Temp Sensors

2-Wire Serial

(Master)

SPI

128-bit AES Encryption Accelerator

2.4GH z

Radio

2.4GHz Radio

ROM

128KB

Power

Management

XTAL

O-QPSK

Modem

29-byte

OTP eFuse

2-Wire Serial

(Slave)

Sleep Counter

Watchdog

Timer

Watchdog

Timer

Voltage Supply

Monitor

RAM

32KB

IEEE802.15.4

MAC

Accelerator

Benefits

 Single chip optimized for

simple applications

 Very low current solution for

long battery life – over 10 yrs

 RF4CE in ROM  Variant for JenNet-IP Smart

Devices

 Highly featured 32-bit RISC

CPU for high performance and low power

 System BOM is low in

component count and cost

 Flexible sensor interfacing

options

Applications

 Robust and secure low power

wireless applications using RF4CE

 Remote Control  Toys and gaming peripherals  Active RFID tags  Point-to-point or star networks

using IEEE802.15.4

 Energy harvesting, for example

self powered light switch

 Smart Lighting Networks  Building Automation

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Contents

1 Introduction 6

1.1 Wireless Transceiver 6

1.2 RISC CPU and Memory 6

1.3 Peripherals 7

1.4 Block Diagram 8

2 Pin Configurations 9

2.1 Pin Assignment 10

2.2 Pin Descriptions 12

2.2.1 Power Supplies 12

2.2.2 Reset 12

2.2.3 32MHz Oscillator 12

2.2.4 Radio 12

2.2.5 Analogue Peripherals 13

2.2.6 Digital Input/Output 13

3 CPU 15 4 Memory Organisation 16

4.1 ROM 16

4.2 RAM 17

4.3 OTP eFuse Memory 17

4.4 External Memory 17

4.4.1 External Memory Encryption 18

4.5 Peripherals 18

4.6 Unused Memory Addresses 18

5 System Clocks 19

5.1 16MHz System Clock 19

5.1.1 32MHz Oscillator 19

5.1.2 High-Speed RC Oscillator 20

5.2 32kHz System Clock 20

5.2.1 32kHz RC Oscillator 20

5.2.2 32kHz Crystal Oscillator 20

5.2.3 32kHz External Clock 21

6 Reset 22

6.1 Internal Brown-out Reset 22

6.2 External Reset 23

6.3 Software Reset 23

6.4 Supply Voltage Monitor (SVM) 23

6.5 Watchdog Timer 24

7 Interrupt System 25

7.1 System Calls 25

7.2 Processor Exceptions 25

7.2.1 Bus Error 25

7.2.2 Alignment 25

7.2.3 Illegal Instruction 25

7.2.4 Stack Overflow 25

7.3 Hardware Interrupts 26

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8 Wireless Transceiver 27

8.1 Radio 27

8.1.1 Radio External Components 28

8.1.2 Antenna Diversity 28

8.2 Modem 30

8.3 Baseband Processor 31

8.3.1 Transmit 31

8.3.2 Reception 31

8.3.3 Auto Acknowledge 32

8.3.4 Beacon Generation 32

8.3.5 Security 32

8.4 Security Coprocessor 32

9 Digital Input/Output 33 10 Serial Peripheral Interface 35 11 Timers 38

11.1 Peripheral Timer/Counters 38

11.1.1 Pulse Width Modulation Mode 39

11.1.2 Capture Mode 39

11.1.3 Counter/Timer Mode 40

11.1.4 Delta-Sigma Mode 40

11.1.5 Example Timer/Counter Application 41

11.2 Tick Timer 41

11.3 Wakeup Timers 42

11.3.1 RC Oscillator Calibration 43

12 Pulse Counters 44 13 Serial Communications 45

13.1 Interrupts 46

13.2 UART Application 46

14 JTAG Debug Interface 48 15 Two-Wire Serial Interface (I2C) 49

15.1 Connecting Devices 49

15.2 Clock Stretching 50

15.3 Master Two-wire Serial Interface 50

15.4 Slave Two-wire Serial Interface 52

16 Random Number Generator 53 17 Analogue Peripherals 54

17.1 Analogue to Digital Converter 54

17.1.1 Operation 55

17.1.2 Supply Monitor 56

17.1.3 Temperature Sensor 56

17.2 Comparator 56

18 Power Management and Sleep Modes 57

18.1 Operating Modes 57

18.1.1 Power Domains 57

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18.2 Active Processing Mode 57

18.2.1 CPU Doze 57

18.3 Sleep Mode 57

18.3.1 Wakeup Timer Event 58

18.3.2 DIO Event 58

18.3.3 Comparator Event 58

18.3.4 Pulse Counter 58

18.4 Deep Sleep Mode 58

19 Electrical Characteristics 59

19.1 Maximum Ratings 59

19.2 DC Electrical Characteristics 59

19.2.1 Operating Conditions 59

19.2.2 DC Current Consumption 60

19.2.3 I/O Characteristics 61

19.3 AC Characteristics 61

19.3.1 Reset and Supply Voltage Monitor 61

19.3.2 SPI Master Timing 63

19.3.3 Two-wire Serial Interface 64

19.3.4 Wakeup and Boot Load Timings 64

19.3.5 Bandgap Reference 65

19.3.6 Analogue to Digital Converters 65

19.3.7 Comparator 66

19.3.8 32kHz RC Oscillator 66

19.3.9 32kHz Crystal Oscillator 67

19.3.10 32MHz Crystal Oscillator 67

19.3.11 High-Speed RC Oscillator 68

19.3.12 Temperature Sensor 68

19.3.13 Radio Transceiver 69

Appendix A Mechanical and Ordering Information 75

A.1 SOT618-1 HVQFN40 40-pin QFN Package Drawing 75 A.2 Footprint information 76 A.3 Ordering Information 78 A.4 Device Package Marking 79 A.5 Tape and Reel Information 80 A.5.1 Tape Orientation and Dimensions 80 A.5.2 Reel Information: 180mm Reel 81 A.5.3 Reel Information: 330mm Reel 82 A.5.4 Dry Pack Requirement for Moisture Sensitive Material 82

Appendix B Development Support 83

B.1 Crystal Oscillators 83 B.1.1 Crystal Equivalent Circuit 83 B.1.2 Crystal Load Capacitance 83 B.1.3 Crystal ESR and Required Transconductance 84 B.2 32MHz Oscillator 85 B.3 32kHz Oscillator 87 B.4 JN5142 Module Reference Designs 89 B.4.1 Schematic Diagram 89 B.4.2 PCB Design and Reflow Profile 92 B.4.3 Moisture Sensitivity Level (MSL) 92

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Related Documents 93 RoHS Compliance 93 Status Information 93 Disclaimers 94 Version Control 94 Contact Details 95

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1 Introduction

The JN5142 is an IEEE802.15.4 wireless microcontroller that provides a fully integrated solution for applications using the IEEE802.15.4 standard in the 2.4 - 2.5GHz ISM frequency band [1], including RF4CE. A ROM variant provides support for JenNet-IP “Smart Device” applications such as lighting and building automation.

Applications that transfer data wirelessly tend to be more complex than wired ones. Wireless protocols make stringent demands on frequencies, data formats, timing of data transfers, security and other issues. Application development must consider the requirements of the wireless network in addition to the product functionality and user interfaces. To minimise this complexity, NXP provides a series of software libraries and interfaces that control the transceiver and peripherals of the JN5142. These libraries and interfaces remove the need for the developer to understand wireless protocols and greatly simplifies the programming complexities of power modes, interrupts and hardware functionality.

In view of the above, it is not necessary to provide the register details of the JN5142 in the datasheet. The device includes a Wireless Transceiver, RISC CPU, on chip memory and an extensive range of peripherals.

1.1 Wireless Transceiver

The Wireless Transceiver comprises a 2.45GHz radio, a modem, a baseband controller and a security coprocessor. In addition, the radio also provides an output to control transmit-receive switching of external devices such as power amplifiers allowing applications that require increased transmit power to be realised very easily. Appendix B.4, describes a complete reference design including Printed Circuit Board (PCB) design and Bill Of Materials (BOM).

The security coprocessor provides hardware-based 128-bit AES-CCM* modes as specified by the IEEE802.15.4 2006 standard. Specifically this includes encryption and authentication covered by the MIC –32/-64/-128, ENC and ENC-MIC –32/-64/-128 modes of operation.

The transceiver elements (radio, modem and baseband) work together to provide IEEE802.15.4 (2006) MAC and PHY functionality under the control of a protocol stack. Applications incorporating IEEE802.15.4 functionality can be developed rapidly by combining user-developed application software with a protocol stack library.

1.2 RISC CPU and Memory

A 32-bit RISC CPU allows software to be run on-chip, its processing power being shared between the IEEE802.15.4 MAC protocol, other higher layer protocols and the user application. The JN5142 has a unified memory architecture, code memory, data memory, peripheral devices and I/O ports are organised within the same linear address space. The device contains 128kbytes of ROM, 32kbytes of RAM and a 29-byte One Time Programmable (OTP) eFuse memory.

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1.3 Peripherals

The following peripherals are available on chip:

 Master SPI port with three select outputs  UART with support for hardware or software flow control  One programmable Timer/Counter which supports Pulse Width Modulation (PWM) and capture/compare, plus

three PWM timers which support PWM and Timer modes only.

 Two programmable Sleep Timers and a Tick Timer  Two-wire serial interface (compatible with SMbus and I2C) supporting master and slave operation  Eighteen digital I/O lines (multiplexed with peripherals such as timers and UARTs)  8-bit, Analogue to Digital converter with up to four input channels  Programmable analogue comparator  Internal temperature sensor and battery monitor  Two low power pulse counters  Random number generator  Watchdog Timer and Supply Voltage Monitor  JTAG hardware debug port

User applications access the peripherals using the Integrated Peripherals API. This allows applications to use a tested and easily understood view of the peripherals allowing rapid system development.

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Wireless

Transceiver

32-bit RISC CPU

SPI

Master

MUX

UART0

Security Processor

Digital Baseband

Radio

Programmable

Interrupt

Controller

Timer0

2-wire

Interface

SPICLK SPIMOSI SPIMISO SPISEL0

From Peripherals

RF_IN VCOTUNE

Tick Timer

Voltage

Regulators

1.8V

VDD1 VDD2

IBAIS

VB_XX

SPISEL1 SPISEL2

TXD0 RXD0 RTS0 CTS0

TIM0CK_GT TIM0CAP

TIM0OUT

SIF_D SIF_CLK

Pulse

Counters

PC0

PC1

JTAG

Debug

JTAG_TDI JTAG_TMS JTAG_TCK JTAG_TDO

RAM

32KB

ROM

128KB

OTP

eFuse

Antenna Diversity

ADO ADE

CPU and 16MHz

System Clock

32kHz Clock

Generator

XTAL_IN

XTAL_OUT

Clock

Divider/

Multiplier

High-speed

RC Osc

Watchdog

Timer

Voltage Supply

Monitor

Reset

Wakeup

Timer1

Wakeup Timer0

RESETN

32kHz Clock

Select

32KIN

Comparator1

COMP1P*

COMP1M*

ADC

M U

ADC4*

ADC1

VREF/ADC2

ADC3*

Temperature

Sensor

Supply Monitor

32kHz

Osc

32kHz

Clock

Gen

32KXTALIN 32KXTALOUT

PWMs

*Multiplexed with DIO pins

PWM1

PWM3

PWM2

DIO6/TXD0/JTAG_TDO/PWM2

DIO7/RXD0/JTAG_TDI/PWM3

DIO4/CTS0/JTAG_TCK/TIM0OUT

DIO5/RTS0/JTAG_TMS/PWM1/PC1

DIO17/COMP1M/SIF_D

DIO10/TIM0OUT/32KXTALOUT

DIO0/SPISEL1/ADC3

DIO3/RFTX/TIM0CAP

DIO2/RFRX/TIM0CK_GT

DIO1/SPISEL2/PC0/ADC4

DIO9/TIM0CAP/32KXTALIN

DIO8/TIM0CK_GT/PC1

DIO13/PWM3/ADE/RTS0/JTAG_TMS

DIO11/PWM1

DIO12/PWM2/ADO/CTS0/JTAG_TCK

DIO14/SIF_CLK/TXD0/JTAG_TD0/SPISEL1

DIO15/SIF_D/RXD0/JTAG_TDI/SPISEL2

DIO16/COMP1P/SIF_CLK

1.4 Block Diagram

Figure 1: JN5142 Block Diagram

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2 Pin Configurations

40 39 38 37 36 35 34 33 32 31

VSSA

1918

1716

1514

131211

DIO16/COMP1P/SIF_CLK

DIO17/COMP1M/SIF_D

RESETN

XTAL_OUT

XTAL_IN

VB_SYNTH

VCOTUNE

VB_VCO

VDD1

IBIAS

VREF/ADC2

VB_RF2

RF_IN

VB_RF1

ADC1

DIO0/SPISEL1/ADC3

DIO1/SPISEL2/PC0/ADC4

DIO2/RFRX/TIM0CK_GT

DIO3/RFTX/TIM0CAP

SPICLK

VSS1

SPIMISO

SPIMOSI

SPISELO

VB_RAM

DIO4/CTS0*/TIM0OUT

DIO5/RTS0*/PWM1/PC1

DIO6/TXD0*/PWM2

DIO7/RXD0*/PWM3

VDD2

DIO15/SIF_D/RXD0*/SPISEL2 VSS2 DIO14/SIF_CLK/TXD0*/SPISEL1 DIO13/ADE/PWM3/RTS0*

DIO12/ADO/PWM2/CTS0*

VB_DIG DIO11/PWM1 DIO10/TIM0OUT/32KXTALOUT DIO9/TIM0CAP/32KXTALIN/32KIN DIO8/TIM0CK_GT/PC1

*Note: JTAG occupies UART0 pins in either position

 Note: Please refer to Appendix B.4 JN5142 Module Reference

Figure 2: 40-pin QFN Configuration (top view)

Design for important applications information regarding the

connection of the PADDLE to the PCB.

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Pin No

Power supplies

Signal

Type

Description

6, 8, 12, 14, 25, 35

VB_SYNTH, VB_VCO, VB_RF2, VB_RF1, VB_RAM, VB_DIG

1.8V

Regulated supply voltage

9, 30

VDD1, VDD2

3.3V

Supplies: VDD1 for analogue, VDD2 for digital

21, 39, Paddle

VSS1, VSS2, VSSA

Grounds (see appendix A.2 for paddle details)

General

RESETN

CMOS

Reset input

4,5

XTAL_OUT, XTAL_IN

1.8V

System crystal oscillator

Radio

VCOTUNE

1.8V

VCO tuning RC network

IBIAS

1.8V

Bias current control

RF_IN

1.8V

RF antenna

Analogue Peripheral I/O

15, 16, 17

ADC1, ADC3, ADC4

3.3V

ADC inputs

VREF/ADC2

1.8V

Analogue peripheral reference voltage or ADC input 2

1, 2

COMP1P, COMP1M

3.3V

Comparator 1 inputs

Digital Peripheral I/O

Primary

Alternate Functions

SPICLK

CMOS

SPI Clock Output

SPIMISO

CMOS

SPI Master In Slave Out Input

SPIMOSI

CMOS

SPI Master Out Slave In Output

SPISEL0

CMOS

SPI Slave Select Output 0

DIO0

SPISEL1

ADC3

CMOS

DIO0, SPI Slave Select Output 1 or ADC input 3

DIO1

SPISEL2

ADC4

PC0

CMOS

DIO1, SPI Slave Select Output 2, ADC input 4 or Pulse Counter 0 Input

DIO2

TIM0CK_GT

RFRX

CMOS

DIO2, Timer0 Clock/Gate Input or Radio Receive Control Output

DIO3

TIM0CAP

RFTX

CMOS

DIO3, Timer0 Capture Input or Radio Transmit Control Output

DIO4

CTS0

JTAG_TCK

TIM0OUT

CMOS

DIO4, UART 0 Clear To Send Input, JTAG CLK or Timer0 PWM Output

DIO5

RTS0

JTAG_TMS

PWM1

PC1

CMOS

DIO5, UART 0 Request To Send Output, JTAG Mode Select, PWM1 Output or Pulse Counter 1 Input

DIO6

TXD0

JTAG_TDO

PWM2

CMOS

DIO6, UART 0 Transmit Data Output, JTAG Data Output or PWM2 Output

DIO7

RXD0

JTAG_TDI

PWM3

CMOS

DIO7, UART 0 Receive Data Input, JTAG Data Input or PWM 3 Output

DIO8

TIM0CK_GT

PC1

CMOS

DIO8, Timer0 Clock/Gate Input or Pulse Counter1 Input

DIO9

TIM0CAP

32KXTALIN

CMOS

DIO9, Timer0 Capture Input or 32K External Crystal Input

2.1 Pin Assignment

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Digital Peripheral I/O

Primary

Alternate Functions

DIO10

TIM0OUT

32KXTALOUT

CMOS

DIO10, Timer0 PWM Output or 32K External Crystal Output

DIO11

PWM1

CMOS

DIO11 or PWM1 Output

DIO12

PWM2

CTS0

JTAG_TCK

ADO

CMOS

DIO12, PWM2 Output, UART 0 Clear To Send Input, JTAG CLK or Antenna Diversity Odd

DIO13

PWM3

RTS0

JTAG_TMS

ADE

CMOS

DIO13, PWM3 Output, UART 0 Request To Send Output, JTAG Mode Select or Antenna Diversity Even

DIO14

SIF_CLK

TXD0

JTAG_TDO

SPISEL1

CMOS

DIO14, Serial Interface Clock, UART 0 Transmit Data Output, JTAG Data Output or SPI Slave Select Output 1

DIO15

SIF_D

RXD0

JTAG_TDI

SPISEL2

CMOS

DIO15, Serial Interface Data, UART 0 Receive Data Input, JTAG Data Input or SPI Slave Select Output 2

DIO16

COMP1P

SIF_CLK

CMOS

DIO16, Comparator Positive Input or Serial Interface clock

DIO17

COMP1M

SIF_D

CMOS

DIO17, Comparator Negative Input or Serial Interface Data

 The PCB schematic and layout rules detailed in Appendix B.4

must be followed. Failure to do so will likely result in the JN5142 failing to meet the performance specification detailed herein and worst case may result in device not functioning in the end application.

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2.2 Pin Descriptions

2.2.1 Power Supplies

The device is powered from the VDD1 and VDD2 pins, each being decoupled with a 100nF ceramic capacitor. VDD1 is the power supply to the analogue circuitry; it should be decoupled to ground. VDD2 is the power supply for the digital circuitry; and should also be decoupled to ground. In addition, a common 10µF tantalum capacitor is required for low frequencies. Decoupling pins for the internal 1.8V regulators are provided which each require a 100nF capacitor located as close to the device as practical. VB_SYNTH, VB_RAM and VB_DIG require only a 100nF capacitor. VB_RF and VB_RF2 should be connected together as close to the device as practical, and require one 100nF capacitor and one 47pF capacitor. The pin VB_VCO requires a 10nF capacitor. Refer to B.4.1 for schematic diagram.

VSSA, VSS1, VSS2 are the ground pins. Users are strongly discouraged from connecting their own circuits to the 1.8v regulated supply pins, as the regulators

have been optimised to supply only enough current for the internal circuits.

2.2.2 Reset

RESETN is an active low reset input pin that is connected to a 300kΩ internal pull-up resistor. It may be pulled low by an external circuit. Refer to Section 6.2 for more details.

2.2.3 32MHz Oscillator

A crystal is connected between XTALIN and XTALOUT to form the reference oscillator, which drives the system clock. A capacitor to analogue ground is required on each of these pins. Refer to Section 5.1 for more details. The 32MHz reference frequency is divided down to 16MHz and this is used as the system clock throughout the device.

2.2.4 Radio

The radio is a single ended design, requiring a capacitor and just two inductors to match to 50Ω microstrip line to the RF_IN pin.

An external resistor (43kΩ) is required between IBIAS and analogue ground to set various bias currents and references within the radio.

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2.2.5 Analogue Peripherals

VDD1

Analogue

I/O Pin

VSSA

Analogue

Peripheral

The ADC requires a reference voltage to use as part of its operation. It can use either an internal reference voltage or an external reference connected to VREF. This voltage is referenced to analogue ground and the performance of the analogue peripherals is dependent on the quality of this reference.

There are four ADC inputs and a pair of comparator inputs. ADC1 has a designated input pin but ADC2 uses the same pin as VREF, invalidating its use as an ADC pin when an external reference voltage is required. The remaining 2 ADC channels are shared with the digital I/Os DIO0 and DIO1 and connect to pins 16 and 17. When these two ADC channels are selected, the corresponding DIOs must be configured as Inputs with their pull-ups disabled. Similarly, the comparator shares pins 1 and 2 with DIO16 and DIO17, so when the comparator is selected these pins must be configured as Inputs with their pull-ups disabled. The analogue I/O pins on the JN5142 can have signals applied up to 0.3v higher than VDD1. A schematic view of the analogue I/O cell is shown in Figure 3. Figure 4 demonstrates a special case, where a digital I/O pin doubles as an input to analogue devices. This applies to ADC3, ADC4, COMP1P and COMP1M.

In reset, sleep and deep sleep, the analogue peripherals are all off. In sleep, the comparator may optionally be used as a wakeup source.

Unused ADC and comparator inputs should not be left unconnected, for example connected to analogue ground.

Figure 3: Analogue I/O Cell

2.2.6 Digital Input/Output

Most digital I/O pins on the JN5142 can have signals applied up to 2V higher than VDD2 (with the exception of DIOs 0, 1, 9, 10, 15, 16 and 17, which are 3V tolerant) are therefore TTL-compatible with VDD2 > 3V. For other DC properties of these pins see Section 19.2.3.

When used in their primary function all Digital Input/Output pins are bi-directional and are connected to weak internal pull up resistors (40k nominal) that can be disabled. When used in their secondary function (selected when the appropriate peripheral block is enabled through software library calls) then their direction is fixed by the function. The pull up resistor is enabled or disabled independently of the function and direction; the default state from reset is enabled.

A schematic view of the digital I/O cell is in Figure 4. The dotted lines through resistor R exists only on DIO0, DIO1, DIO15, DIO16 and DIO17 which are also inputs to the ADC (ADC3, ADC4) and Comparator (COMP1P, COMP1M) respectively. To use these DIO pins for their analogue functions, the DIO must be set as an Input with its pull-up resistor, RPU, disabled.

represent a path that

ESD

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VDD2

VSS

DIO[x] Pin

ESD

ADC or

COMP1 Input

PROT

VSS

Figure 4: DIO Pin Equivalent Schematic

In reset, the digital peripherals are all off and the DIO pins are set as high-impedance inputs. During sleep and deep sleep, the DIO pins retain both their input/output state and output level that was set as sleep commences. If the DIO pins were enabled as inputs and the interrupts were enabled then these pins may be used to wake up the JN5142 from sleep.

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3 CPU

The CPU of the JN5142 is a 32-bit load and store RISC processor. It has been architected for three key requirements:

 Low power consumption for battery powered applications  High performance to implement a wireless protocol at the same time as complex applications  Efficient coding of high-level languages such as C provided with the Software Developers Kit

It features a linear 32-bit logical address space with unified memory architecture, accessing both code and data in the same address space. Registers for peripheral units, such as the timers, UART and the baseband processor are also mapped into this space.

The CPU has access to a block of 15 32-bit General-Purpose (GP) registers together with a small number of special purpose registers which are used to store processor state and control interrupt handling. The contents of any GP register can be loaded from or stored to memory, while arithmetic and logical operations, shift and rotate operations, and signed and unsigned comparisons can be performed either between two registers and stored in a third, or between registers and a constant carried in the instruction. Operations between general or special-purpose registers execute in one cycle while those that access memory require a further cycle to allow the memory to respond.

The instruction set manipulates 8, 16 and 32-bit data; this means that programs can use objects of these sizes very efficiently. Manipulation of 32-bit quantities is particularly useful for protocols and high-end applications allowing algorithms to be implemented in fewer instructions than on smaller word-size processors, and to execute in fewer clock cycles. In addition, the CPU supports hardware Multiply that can be used to efficiently implement algorithms needed by Digital Signal Processing applications.

The instruction set is designed for the efficient implementation of high-level languages such as C. Access to fields in complex data structures is very efficient due to the provision of several addressing modes, together with the ability to be able to use any of the GP registers to contain the address of objects. Subroutine parameter passing is also made more efficient by using GP registers rather than pushing objects onto the stack. The recommended programming method for the JN5142 is by using C, which is supported by a software developer kit comprising a C compiler, linker and debugger.

The CPU architecture also contains features that make the processor suitable for embedded, real-time applications. In some applications, it may be necessary to use a real-time operating system to allow multiple tasks to run on the processor. To provide protection for device-wide resources being altered by one task and affecting another, the processor can run in either supervisor or user mode, the former allowing access to all processor registers, while the latter only allows the GP registers to be manipulated. Supervisor mode is entered on reset or interrupt; tasks starting up would normally run in user mode in a RTOS environment.

Embedded applications require efficient handling of external hardware events. Exception processing (including reset and interrupt handling) is enhanced by the inclusion of a number of special-purpose registers into which the PC and status register contents are copied as part of the operation of the exception hardware. This means that the essential registers for exception handling are stored in one cycle, rather than the slower method of pushing them onto the processor stack. The PC is also loaded with the vector address for the exception that occurred, allowing the handler to start executing in the next cycle.

To improve power consumption a number of power-saving modes are implemented in the JN5142, described more fully in Section 18. One of these modes is the CPU doze mode; under software control, the processor can be shut down and on an interrupt it will wake up to service the request. Additionally, it is possible under software control, to set the speed of the CPU to 1, 2, 4, 8, 16 or 32MHz. This feature can be used to trade-off processing power against current consumption.

Page 16

0x00000000

0x00020000

RAM

(32KB)

0xF0000000

0xFFFFFFFF

Unpopulated

ROM

(128KB)

0xF0008000

RAM Echo

0x04000000

Peripherals

0x02000000

Interrupt Vectors

Interrupt Manager

Boot Loader

IEEE802.15.4

Stack

0x00000000

0x00020000

APIs

Spare

Network Stack

4 Memory Organisation

This section describes the different memories found within the JN5142. The device contains ROM, RAM, OTP eFuse memory, the wireless transceiver and peripherals all within the same linear address space.

Figure 5: JN5142 Memory Map

4.1 ROM

The ROM is 128k bytes in size, and can be accessed by the processor in a single CPU clock cycle. The ROM contents include bootloader to allow external Flash memory contents to be bootloaded into RAM at runtime, a default interrupt vector table, an interrupt manager, IEEE802.15.4 MAC and APIs for interfacing on-chip peripherals. The operation of the boot loader is described in detail in Application Note [9]. The interrupt manager routes interrupt calls to the application‟s soft interrupt vector table contained within RAM. Section 7 contains further information regarding the handling of interrupts. ROM contents are shown in Figure 6.

16 JN-DS-JN5142 1v0 © NXP Laboratories UK 2012

Figure 6: Typical ROM Contents

Page 17

4.2 RAM

MAC Data

Interrupt Vector Table

Application

CPU Stack

(Grows Down)

0x04000000

0x04008000

MAC Address

JN5142

Serial

Memory

SPISEL0 SPIMISO SPIMOSI

SPICLK

SDO SDI CLK

The JN5142 contains 32KBytes of high speed RAM. It can be used for both code and data storage and is accessed by the CPU in a single clock cycle. At reset, a boot loader controls the loading of segments of code and data from an external memory connected to the SPI port, into RAM. Software can control the power supply to the RAM allowing the contents to be maintained during a sleep period when other parts of the device are un-powered. Typical RAM contents are shown in Figure 7.

Figure 7: Typical RAM Contents

4.3 OTP eFuse Memory

The JN5142 contains a total of 29bytes of eFuse memory; this is a One Time Programmable (OTP) memory that can be used to support a 40-bit MAC ID (For a 64-bit MAC ID, the 24 bit company ID, OUI, can be stored in the external memory) and a 128-bit AES security key. A limited number of bits are available for customer use for storage of configuration information; configuration of these is made through use of software APIs.

For further information on how to program and use the eFuse memory, please contact technical support via the online tech-support system.

Alternatively, NXP can provide an eFuse programming service for customers that wish to use the eFuse but do not wish to undertake this for themselves. For further details of this service, please contact your local NXP sales office.

4.4 External Memory

An external memory with an SPI interface may be used to provide storage for program code and data for the device when external power is removed. The memory is connected to the SPI interface using select line SPISEL0; this select line is dedicated to the external memory interface and is not available for use with other external devices. See Figure 8 for connection details.

Figure 8: Connecting External Serial Memory

Page 18

Manufacturer

Part Number

Size

Type

Micron

(Numonyx)

M25P10A M25P05A

1 Mbit

512 kbit

Flash Flash

Winbond

W25X20B W25X10B

2 Mbit 1 Mbit

Flash Flash

Microchip

25AA080 25AA160 25AA320

8 kbit 16 kbit 32 kbit

EEPROM

At reset, the contents of this memory are copied into RAM by the software boot loader. The Flash and EEPROM memory devices that are supported as standard through the JN5142 bootloader are given in Table 1. NXP recommends that where possible one of these devices should be selected.

Table 1: Supported Flash and EEPROM Memories

Applications wishing to use an alternate Flash memory device should refer to Application Note [2]. This application note provides guidance on developing an interface to an alternate device.

4.4.1 External Memory Encryption

The contents of the external serial memory may be encrypted. The AES security processor combined with a user programmable 128-bit encryption key is used to encrypt the contents of the external memory. The encryption key is stored in eFuse.

When bootloading program code from external serial memory, the JN5142 automatically accesses the encryption key to execute the decryption process. User program code does not need to handle any of the decryption process; it is transparent.

With encryption enabled, the time taken to boot code from external flash is increased.

4.5 Peripherals

All peripherals have their registers mapped into the memory space. Access to these registers requires 3 clock cycles. Applications have access to the peripherals through the software libraries that present a high-level view of

the peripheral‟s functions through a series of dedicated software routines. These routines provide both a tested

method for using the peripherals and allow bug-free application code to be developed more rapidly. For details, see [5].

4.6 Unused Memory Addresses

Any attempt to access an unpopulated memory area will result in a bus error exception (interrupt) being generated.

18 JN-DS-JN5142 1v0 © NXP Laboratories UK 2012

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5 System Clocks

XTALOUT

XTALIN

JN5142

Two system clocks are used to provide timing references into the on-chip subsystems of the JN5142. A 16MHz clock, generated by a crystal-controlled 32MHz oscillator, is used by the transceiver, processor, memory and digital and analogue peripherals. A 32kHz clock is used by the sleep timer and is generated by one of two on-chip oscillators or can be supplied externally.

5.1 16MHz System Clock

The 16MHz system clock is used by the digital and analogue peripherals and the transceiver. A scaled version (1,2,4,8,16 or 32MHz) of this clock is also used by the processor and memories. For most operations it is necessary to source this clock from the 32MHz oscillator.

Crystal oscillators are generally slow to start. Hence to provide a faster start-up following a sleep cycle a fast RC oscillator is provided that can be used as the source for the 16MHz system clock. The oscillator starts very quickly and can run at 27MHz or 32MHz (calibrated), giving system clock speeds of either 13.5MHz or 16MHz. Using the oscillator at 27MHz scales down the speed of the processor and any peripherals in use. For the SPI interface this causes no functional issues as the generated SPI clock is slightly slower and is used to clock the external SPI slave. Use of the radio or UART is not possible when using the high-speed RC oscillator, as even after calibration there is a +/- 7.5% tolerance. Additionally, timers should be used with care as the exact frequency will not be known.

On wake-up from sleep, the JN5142 uses the Fast RC oscillator. It can then either:

 Automatically switch over to use the 32MHz clock source when it has started up.  Continue to use the fast RC oscillator until software triggers the switch-over to the 32MHz clock source, for

example when the radio is required.  Continue to use the RC oscillator until the device goes back into one of the sleep modes. Compared to the JN5148, the use of the fast RC Oscillator at wake-up means, there is no need to wait for the 32MHz

crystal oscillator to start, if it is necessary to download code from the external memory. Consequently, in this situation, application code will start executing earlier, with a typical improvement of 550µsec.

5.1.1 32MHz Oscillator

The JN5142 contains the necessary on chip components to build a 32MHz reference oscillator with the addition of an external crystal resonator and two tuning capacitors. The schematic of these components are shown in Figure 9. The two capacitors, C1 and C2, should typically be 15pF and use a COG dielectric. Due to the small size of these capacitors, it is important to keep the traces to the external components as short as possible. The on chip transconductance amplifier is compensated for temperature variation, and is self-biasing by means of the internal resistor R1. This oscillator provides the frequency reference for the radio and therefore it is essential that the reference PCB layout and BOM are carefully followed. The electrical specification of the oscillator can be found in Section 19.3.10. Please refer to Appendix B for development support with the crystal oscillator circuit.

Figure 9: 32MHz Crystal Oscillator Connections

Page 20

32KXTALOUT32KXTALIN

JN5142

5.1.2 High-Speed RC Oscillator

An on-chip High-Speed RC oscillator is provided, capable of running at either 27MHz typical or 32MHz typical once calibrated, using the software API function. No external components are required for this oscillator. The electrical specification of the oscillator can be found in Section 19.3.11.

5.2 32kHz System Clock

The 32kHz system clock is used for timing the length of a sleep period (see Section 18). The clock can be selected from one of three sources through the application software:

 32kHz RC Oscillator  32kHz Crystal Oscillator  32kHz External Clock

Upon a chip reset or power-up the JN5142 defaults to using the internal 32kHz RC Oscillator. If another clock source is selected then it will remain in use for all 32kHz timing until a chip reset is performed.

5.2.1 32kHz RC Oscillator

The internal 32kHz RC oscillator requires no external components. The internal timing components of the oscillator have a wide tolerance due to manufacturing process variation and so the oscillator runs nominally at 32kHz ±30%. To make this useful as a timing source for accurate wakeup from sleep, a frequency calibration factor derived from the more accurate 16MHz clock may be applied. The calibration factor is derived through software, details can be found in Section 11.3.1. Software must check that the 32kHz RC oscillator is running before using it. For detailed electrical specifications, see Section 19.3.8.

5.2.2 32kHz Crystal Oscillator

In order to obtain more accurate sleep periods, the JN5142 contains the necessary on-chip components to build a 32kHz oscillator with the addition of an external 32.768kHz crystal and two tuning capacitors. The crystal should be connected between 32KXTALIN and 32KXTALOUT (DIO9 and DIO10), with two equal capacitors to ground, one on each pin. Due to the small size of the capacitors, it is important to keep the traces to the external components as short as possible.

The electrical specification of the oscillator can be found in Section 19.3.9. The oscillator cell is flexible and can operate with a range of commonly available 32.768kHz crystals with load capacitances from 6 to 12.5pF. However, the maximum ESR of the crystal and the supply current are both functions of the actual crystal used, see Appendix B.1 for more details.

Figure 10: 32kHz Crystal Oscillator Connections

20 JN-DS-JN5142 1v0 © NXP Laboratories UK 2012

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5.2.3 32kHz External Clock

An externally supplied 32kHz reference clock on the 32KIN input (DIO9) may be provided to the JN5142. This would allow the 32kHz system clock to be sourced from a very stable external oscillator module, allowing more accurate sleep cycle timings compared to the internal RC oscillator. (See Section 19.2.3, DIO9 is a 3V tolerant input)

Page 22

Internal RESET

VDD

6 Reset

A system reset initialises the device to a pre-defined state and forces the CPU to start program execution from the reset vector. The reset process that the JN5142 goes through is as follows.

When power is first applied or when the external reset is released, the High-Speed RC oscillator and 32MHz crystal oscillator are activated. After a short wait period (13sec approx) while the High-Speed RC starts up, and so long as the supply voltage satisfies the default Supply Voltage Monitor (SVM) threshold (2.0V+0.045V hysteresis), the internal 1.8V regulators are turned on to power the processor and peripheral logic. This is followed by a further wait (again 13sec approx) before the eFuse SVM threshold is read and applied. After a brief pause (approx 2.5sec) the SVM is checked again with the new threshold and if successful, the internal reset is removed from the CPU and peripheral logic and the CPU starts to run code beginning at the reset vector, consisting of initialisation code and the resident boot loader. [9] Section 19.3.1 provides detailed electrical data and timing.

The JN5142 has five sources of reset:

 Internal Power-on / Brown-out Reset (BOR)  External Reset  Software Reset  Watchdog timer  Supply Voltage detect

 Note: When the device exits a reset condition, device operating

parameters (voltage, frequency, temperature, etc.) must be met to ensure operation. If these conditions are not met, then the device must be held in reset until the operating conditions are met. (See Section 19.3)

6.1 Internal Power-On / Brown-out Reset (BOR)

For the majority of applications the internal power-on reset is capable of generating the required reset signal. When power is applied to the device, the power-on reset circuit monitors the rise of the VDD supply. When the VDD reaches the specified threshold, the reset signal is generated. This signal is held internally until the power supply and oscillator stabilisation time has elapsed, when the internal reset signal is then removed and the CPU is allowed to run.

The BOR circuit has the ability to reject spikes on the VDD rail to avoid false triggering of the reset module. Typically for a negative going square pulse of duration 1uS, the voltage must fall to 1.2v before a reset is generated. Similarly for a triangular wave pulse of 10us width, the voltage must fall to 1.3v before causing a reset. The exact characteristics are complex and these are only examples.

Figure 11: Internal Power-on Reset

When the supply drops below the power on reset „falling‟ threshold, it will re-trigger the reset. If necessary, use of the external reset circuit show in Figure 12 is suggested.

22 JN-DS-JN5142 1v0 © NXP Laboratories UK 2012

Page 23

RESETN

JN5142

VDD

18k

470nF

Internal Reset

RESETN pin

Reset

Figure 12: External Reset Generation

The external resistor and capacitor provide a simple reset operation when connected to the RESETN pin.

6.2 External Reset

An external reset is generated by a low level on the RESETN pin. Reset pulses longer than the minimum pulse width will generate a reset during active or sleep modes. Shorter pulses are not guaranteed to generate a reset. The JN5142 is held in reset while the RESETN pin is low. When the applied signal reaches the Reset Threshold Voltage (V

) on its positive edge, the internal reset process starts.

RST

The JN5142 has an internal 300kΩ pull-up resistor connect to the RESETN pin. The pin is an input for an external reset only.

Figure 13: External Reset

6.3 Software Reset

A system reset can be triggered at any time through software control, causing a full chip reset and invalidating the

RAM contents. For example this can be executed within a user‟s application upon detection of a system failure.

6.4 Supply Voltage Monitor (SVM)

An internal Supply Voltage Monitor (SVM) is used to monitor the supply voltage to the JN5142; this can be used whilst the device is awake or is in CPU doze mode. Dips in the supply voltage below a variable threshold can be detected and can be used to cause the JN5142 to perform a chip reset. Equally, dips in the supply voltage can be detected and used to cause an interrupt to the processor, when the voltage either drops below the threshold or rises above it.

The supply voltage detect is enabled by default from power-up and can extend the reset during power-up. This will keep the CPU in reset until the voltage exceeds the SVM threshold voltage. The threshold voltage is configurable to

1.95V, 2.0V, 2.1V, 2.2V, 2.3V, 2.4V, 2.7V and 3.0V and is controllable by software. From power-up the threshold is

Page 24

set by eFuse settings and the default chip configuration is for the 2.3V threshold. It is recommended that the threshold is set so that, as a minimum, the chip is held in reset until the voltage reaches the level required by the external memory device on the SPI interface.

6.5 Watchdog Timer

A watchdog timer is provided to guard against software lockups. It operates by counting cycles of the high-speed RC system clock. A pre-scaler is provided to allow the expiry period to be set between typically 8ms and 16.4 seconds (dependent on high-speed RC accuracy: +30%, -15%). Failure to restart the watchdog timer within the pre-configured timer period will cause a chip reset to be performed. A status bit is set if the watchdog was triggered so that the software can differentiate watchdog initiated resets from other resets, and can perform any required recovery once it restarts.

After power up, reset, start from deep sleep or start from sleep, the watchdog is always enabled with the largest timeout period and will commence counting as if it had just been restarted. Under software control the watchdog can be disabled. If it is enabled, the user must regularly restart the watchdog timer to stop it from expiring and causing a reset. The watchdog runs continuously, even during doze, however the watchdog does not operate during sleep or deep sleep, or when the hardware debugger has taken control of the CPU. It will recommence automatically if enabled once the debugger un-stalls the CPU.

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7 Interrupt System

Interrupt Source

Vector Location

Interrupt Definition

Bus error

0x08

Typically cause by an attempt to access an invalid address or a disabled peripheral

Tick timer

0x0e

Tick timer interrupt asserted

Alignment error

0x14

Load/store address to non-naturally-aligned location

Illegal instruction

0x1a

Attempt to execute an unrecognised instruction

Hardware interrupt

0x20

interrupt asserted

System call

0x26

System call initiated by b.sys instruction

Trap

0x2c

caused by the b.trap instruction or the debug unit

Reset

0x38

Caused by software or hardware reset.

Stack Overflow

0x3e

Stack overflow

The interrupt system on the JN5142 is a hardware-vectored interrupt system. The JN5142 provides several interrupt sources, some associated with CPU operations (CPU exceptions) and others which are used by hardware in the device. When an interrupt occurs, the CPU stops executing the current program and loads its program counter with a fixed hardware address specific to that interrupt. The interrupt handler or interrupt service routine is stored at this location and is run on the next CPU cycle. Execution of interrupt service routines is always performed in supervisor mode. Interrupt sources and their vector locations are listed in Table 2 below:

Table 2: Interrupt Vectors

7.1 System Calls

The b.trap and b.sys instructions allow processor exceptions to be generated by software. A system call exception will be generated when the b.sys instruction is executed. This exception can, for example, be

used to enable a task to switch the processor into supervisor mode when a real time operating system is in use. (See Section 3 for further details.)

The b.trap instruction is commonly used for trapping errors and for debugging.

7.2 Processor Exceptions

7.2.1 Bus Error

A bus error exception is generated when software attempts to access a memory address that does not exist, or is not populated with memory or peripheral registers or when writing to ROM.

7.2.2 Alignment

Alignment exceptions are generated when software attempts to access objects that are not aligned to natural word boundaries. 16-bit objects must be stored on even byte boundaries, while 32-bit objects must be stored on quad byte boundaries. For instance, attempting to read a 16-bit object from address 0xFFF1 will trigger an alignment exception as will a read of a 32-bit object from 0xFFF1, 0xFFF2 or 0xFFF3. Examples of legal 32-bit object addresses are 0xFFF0, 0xFFF4, 0xFFF8 etc.

7.2.3 Illegal Instruction

If the CPU reads an unrecognised instruction from memory as part of its instruction fetch, it will cause an illegal instruction exception.

7.2.4 Stack Overflow

When enabled, a stack overflow exception occurs if the stack pointer reaches a programmable location.

Page 26

7.3 Hardware Interrupts

Hardware interrupts generated from the transceiver, analogue or digital peripherals and DIO pins are individually masked using the Programmable Interrupt Controller (PIC). Management of interrupts is provided in the peripherals library [5]. For details of the interrupts generated from each peripheral see the respective section in this datasheet.

Interrupts can be used to wake the JN5142 from sleep. The peripherals, baseband controller, security coprocessor and PIC are powered down during sleep but the DIO interrupts and optionally the pulse counters, wake-up timers and analogue comparator interrupts remain powered to bring the JN5142 out of sleep.

Prioritised external interrupt handling (i.e., interrupts from hardware peripherals) is provided to enable an application to control an events priority to provide for deterministic program execution.

The priority Interrupt controller provides 15 levels of prioritised interrupts. The priority level of all interrupts can be set, with value 0 being used to indicate that the source can never produce an external interrupt, 1 for the lowest priority source(s) and 15 for the highest priority source(s). Note that multiple interrupt sources can be assigned the same priority level if desired.

If while processing an interrupt, a new event occurs at the same or lower priority level, a new external interrupt will not be triggered. However, if a new higher priority event occurs, the external interrupt will again be asserted, interrupting the current interrupt service routine.

Once the interrupt service routine is complete, lower priority events can be serviced.

26 JN-DS-JN5142 1v0 © NXP Laboratories UK 2012

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8 Wireless Transceiver

LNA

synth

ADC

Reference

& Bias

Switch

Radio

Calibration

Lim1

Lim2

Lim3

Lim4

sigma

delta

D-Type

The wireless transceiver comprises a 2.45GHz radio, modem, a baseband processor, a security coprocessor and PHY controller. These blocks, with protocol software provided as a library, implement an IEEE802.15.4 standardsbased wireless transceiver that transmits and receives data over the air in the unlicensed 2.4GHz band.

8.1 Radio

Figure 14 shows the single ended radio architecture.

Figure 14: Radio Architecture

The radio comprises a low-IF receive path and a direct modulation transmit path, which converge at the TX/RX switch. The switch connects to the external single ended matching network, which consists of two inductors and a capacitor, this arrangement creates a 50 port and removes the need for a balun. A 50 single ended antenna can be connected directly to this port.

The 32MHz crystal oscillator feeds a divider, which provides the frequency synthesiser with a reference frequency. The synthesiser contains programmable feedback dividers, phase detector, charge pump and internal Voltage Controlled Oscillator (VCO). The VCO has no external components, and includes calibration circuitry to compensate for differences in internal component values due to process and temperature variations. The VCO is controlled by a Phase Locked Loop (PLL) that has an internal loop filter. A programmable charge pump is also used to tune the loop characteristic.

The receiver chain starts with the low noise amplifier/mixer combination whose outputs are passed to a low pass filter, which provides the channel definition. The signal is then passed to a series of amplifier blocks forming a limiting strip. The signal is converted to a digital signal before being passed to the Modem. The gain control for the RX path is derived in the automatic gain control (AGC) block within the Modem, which samples the signal level at various points down the RX chain. To improve the performance and reduce current consumption, automatic calibration is applied to various blocks in the RX path.

In the transmit direction, the digital stream from the Modem is passed to a digital sigma-delta modulator which controls the feedback dividers in the synthesiser, (dual point modulation). The VCO frequency now tracks the applied modulation. The 2.4 GHz signal from the VCO is then passed to the RF Power Amplifier (PA), whose power control can be selected from one of three settings. The output of the PA drives the antenna via the RX/TX switch

Page 28

R1 43K

IBIAS

C20 100nF

L2 2.7nH

VB_RF

VREF

VB_RF2

RF_IN

C3 100nF

C12 47pF

VB_RF1

C1 47pF

L1 5.6nH

To Coaxial Socket

or Integrated Antenna

VB_RF

8.1.1 Radio External Components

In order to realise the full performance of the radio it is essential that the reference PCB layout and BOM are carefully followed. See Appendix B.4.

The radio is powered from a number of internal 1.8V regulators fed from the analogue supply VDD1, in order to provide good noise isolation between the digital logic of the JN5142 and the analogue blocks. These regulators are also controlled by the baseband controller and protocol software to minimise power consumption. Decoupling for internal regulators is required as described in Section 2.2.1.

For single ended antennas or connectors, a balun is not required, however a matching network is needed. The RF matching network requires three external components and the IBIAS pin requires one external component as

shown in schematic in B.4.1. These components are critical and should be placed close to the JN5142 pins and analogue ground as defined in Table 13. Specifically, the output of the network comprising L2, C1 and L1 is designed to present an accurate match to a 50 ohm resistive network as well as provide a DC path to the final output stage or antenna. Users wishing to match to other active devices such as amplifiers should design their networks to match to 50 ohms at the output of L1

8.1.2 Antenna Diversity

Support is provided for antenna diversity. Antenna diversity is a technique that maximises the performance of an antenna system. It allows the radio to switch between two antennas that have very low correlation between their received signals. Typically, this is achieved by spacing two antennas around 0.25 wavelengths apart or by using two orthogonal polarisations. So, if a packet is transmitted and no acknowledgement is received, the radio system can switch to the other antenna for the retry, with a different probability of success.

The JN5142 provides an output (ADO) on DIO12 that is asserted on odd numbered retries and optionally its complement (ADE) on DIO13, that can be used to control an antenna switch; this enables antenna diversity to be implemented easily (see Figure 16 and Figure 17).

28 JN-DS-JN5142 1v0 © NXP Laboratories UK 2012

Figure 15: External Radio Components

Page 29

Antenna A

Antenna B

COM

SEL

SELB

ADO (DIO[12])

ADE (DIO[13])

Device RF Port

RF Switch: Single-Pole, Double-Throw (SPDT)

ADO (DIO[12])

TX Active

RX Active

ADE (DIO[13])

1st TX-RX Cycle 2nd TX-RX Cycle (1st Retry)

Figure 16: Simple Antenna Diversity Implementation using External RF Switch

Figure 17: Antenna Diversity ADO Signal for TX with Acknowledgement

If two DIO pins cannot be spared, DIO13 can be configured to be a normal DIO pin, and the inverse of ADO generated with an inverter on the PCB.

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AGC Demodulation

Symbol

Detection

(Despreading)

Modulation Spreading

TX Data

Interface

RX Data Interface

VCO

Sigma-Delta

Modulator

IF Signal

Gain

8.2 Modem

The modem performs all the necessary modulation and spreading functions required for digital transmission and reception of data at 250kbps in the 2450MHz radio frequency band in compliance with the IEEE802.15.4 standard.

Figure 18: Modem Architecture

Features provided to support network channel selection algorithms include Energy Detection (ED), Link Quality Indication (LQI) and fully programmable Clear Channel Assessment (CCA).

The Modem provides a digital Receive Signal Strength Indication (RSSI) that facilitates the implementation of the IEEE 802.15.4 ED function and LQI function.

The ED and LQI are both related to receiver power in the same way, as shown in Figure 19. LQI is associated with a received packet, whereas ED is an indication of signal power on air at a particular moment.

The CCA capability of the Modem supports all modes of operation defined in the IEEE 802.15.4 standard, namely Energy above ED threshold, Carrier Sense and Carrier Sense and/or energy above ED threshold.

Figure 19: Energy Detect Value vs Receive Power Level

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8.3 Baseband Processor

Append

Checksum

Verify

Checksum

CSMA CCA

Backoff

Control

Deserialiser

Serialiser

Tx/Rx

Frame

Buffer

Bitstream

Protocol Timing Engine

Supervisor

Radio

Status

Control

Processor

Bus

Protocol

Timers

Security Coprocessor

Decrypt

Port

Encrypt

Port

AES

Codec

The baseband processor provides all time-critical functions of the IEEE802.15.4 MAC layer. Dedicated hardware guarantees air interface timing is precise. The MAC layer hardware/software partitioning, enables software to implement the sequencing of events required by the protocol and to schedule timed events with millisecond resolution, and the hardware to implement specific events with microsecond timing resolution. The protocol software layer performs the higher-layer aspects of the protocol, sending management and data messages between endpoint and coordinator nodes, using the services provided by the baseband processor.

Figure 20: Baseband Processor

8.3.1 Transmit

A transmission is performed by software writing the data to be transferred into the Tx/Rx Frame Buffer, together with parameters such as the destination address and the number of retries allowed, and programming one of the protocol timers to indicate the time at which the frame is to be sent. This time will be determined by the software tracking the higher-layer aspects of the protocol such as superframe timing and slot boundaries. Once the packet is prepared and protocol timer set, the supervisor block controls the transmission. When the scheduled time arrives, the supervisor controls the sequencing of the radio and modem to perform the type of transmission required. It can perform all the algorithms required by IEEE802.15.4 such as CSMA/CA without processor intervention including retries and random backoffs.

When the transmission begins, the header of the frame is constructed from the parameters programmed by the software and sent with the frame data through the serialiser to the Modem. At the same time, the radio is prepared for transmission. During the passage of the bitstream to the modem, it passes through a CRC checksum generator that calculates the checksum on-the-fly, and appends it to the end of the frame.

8.3.2 Reception

During reception, the radio is set to receive on a particular channel. On receipt of data from the modem, the frame is directed into the Tx/Rx Frame Buffer where both header and frame data can be read by the protocol software. An interrupt may be provided on receipt of the frame header. As the frame data is being received from the modem it is passed through a checksum generator; at the end of the reception the checksum result is compared with the checksum at the end of the message to ensure that the data has been received correctly. An interrupt may be provided to indicate successful packet reception. During reception, the modem determines the Link Quality, which is made available at the end of the reception as part of the requirements of IEEE802.15.4.

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Processor

Interface

AES

Block

Encryption

Controller

AES

Encoder

Key Generation

8.3.3 Auto Acknowledge

Part of the protocol allows for transmitted frames to be acknowledged by the destination sending an acknowledge packet within a very short window after the transmitted frame has been received. The JN5142 baseband processor can automatically construct and send the acknowledgement packet without processor intervention and hence avoid the protocol software being involved in time-critical processing within the acknowledge sequence. The JN5142 baseband processor can also request an acknowledge for packets being transmitted and handle the reception of acknowledged packets without processor intervention.

8.3.4 Beacon Generation

In beaconing networks, the baseband processor can automatically generate and send beacon frames; the repetition rate of the beacons is programmed by the CPU, and the baseband then constructs the beacon contents from data delivered by the CPU. The baseband processor schedules the beacons and transmits them without CPU intervention.

8.3.5 Security

The transmission and reception of secured frames using the Advanced Encryption Standard (AES) algorithm is handled by the security coprocessor and the stack software. The application software must provide the appropriate encrypt/decrypt keys for the transmission or reception. On transmission, the key can be programmed at the same time as the rest of the frame data and setup information.

8.4 Security Coprocessor

The security coprocessor is available to the application software to perform encryption/decryption operations. A hardware implementation of the encryption engine significantly speeds up the processing of the encrypted packets over a pure software implementation. The AES library for the JN5142 provides operations that utilise the encryption engine in the device and allow the contents of memory buffers to be transformed. Information such as the type of security operation to be performed and the encrypt/decrypt key to be used must also be provided.

Figure 21: Security Coprocessor Architecture

32 JN-DS-JN5142 1v0 © NXP Laboratories UK 2012

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9 Digital Input/Output

There are 18 Digital I/O (DIO) pins, which can be configured as either an input or an output, and each has a selectable internal pull-up resistor. Most DIO pins are multiplexed with alternate peripheral features of the device, see Section 2.1. Once a peripheral is enabled it takes precedence over the device pins. Refer to the individual module Sections for a full description of the alternate peripherals functions. Following a reset (and whilst the reset input is held low), all peripherals are off and the DIO pins are configured as inputs with the internal pull-ups turned on.

When a peripheral is not enabled, the DIO pins associated with it can be used as digital inputs or outputs. Each pin can be controlled individually by setting the direction and then reading or writing to the pin.

The individual pull-up resistors, RPU, can also be enabled or disabled as needed and the setting is held through sleep cycles. The pull-ups are generally configured once after reset depending on the external components and functionality. For instance, outputs should generally have the pull-ups disabled. An input that is always driven should also have the pull-up disabled.

When configured as an input each pin can be used to generate an interrupt upon a change of state (selectable transition either from low to high or high to low); the interrupt can be enabled or disabled. When the device is sleeping, these interrupts become events that can be used to wake the device up. Equally the status of the interrupt may be read. See Section 18 for further details on sleep and wakeup.

The state of all DIO pins can be read, irrespective of whether the DIO is configured as an input or an output. Throughout a sleep cycle the direction of the DIO, and the state of the outputs, is held. This is based on the resultant

of the GPIO Data/Direction registers and the effect of any enabled peripherals at the point of entering sleep. Following a wake-up these directions and output values are maintained under control of the GPIO data/direction registers. Any peripherals enabled before the sleep cycle are not automatically re-enabled, this must be done through software after the wake-up.

For example, if DIO0 is configured to be SPISEL1 then it becomes an output. The output value is controlled by the SPI functional block. If the device then enters a sleep cycle, the DIO will remain an output and hold the value being output when entering sleep. After wake-up the DIO will still be an output with the same value but controlled from the GPIO Data/Direction registers. It can be altered with the software functions that adjust the DIO, or the application may re-configure it to be SPISEL1.

Unused DIO pins are recommended to be set as inputs with the pull-up enabled. Two DIO pins can optionally be used to provide control signals for RF circuitry (e.g. switches and PA) in high power

range extenders. DIO3/RFTX is asserted when the radio is in the transmit state and similarly, DIO2/RFRX is asserted when the radio is

in the receiver state.

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SPI

Master

MUX

UART0

DIO6/TXD0/JTAG_TDO/PWM2

DIO7/RXD0/JTAG_TDI/PWM3

DIO4/CTS0/JTAG_TCK/TIM0OUT

DIO5/RTS0/JTAG_TMS/PWM1/PC1

DIO17/COMP1M/SIF_D

Timer0

2-wire

Interface

SPICLK

DIO10/TIM0OUT/32KXTALOUT

SPIMOSI SPIMISO

SPISEL0

DIO0/SPISEL1/ADC3

DIO3/RFTX/TIM0CAP

DIO2/RFRX/TIM0CK_GT

DIO1/SPISEL2/PC0/ADC4

DIO9/TIM0CAP/32KXTALIN

DIO8/TIM0CK_GT/PC1

DIO13/PWM3/ADE/RTS0/JTAG_TMS

DIO11/PWM1

DIO12/PWM2/ADO/CTS0/JTAG_TCK

DIO14/SIF_CLK/TXD0/JTAG_TD0/SPISEL1

DIO15/SIF_D/RXD0/JTAG_TDI/SPISEL2

DIO16/COMP1P/SIF_CLK

SPISEL1 SPISEL2

TXD0 RXD0 RTS0 CTS0

TIM0CK_GT

TIM0CAP

TIM0OUT

SIF_D

SIF_CLK

Pulse

Counters

PC0

PC1

JTAG

Debug

JTAG_TDI

JTAG_TMS JTAG_TCK JTAG_TDO

Antenna

Diversity

ADO ADE

PWMs

PWM1

PWM3

PWM2

Figure 22: DIO Block Diagram

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10 Serial Peripheral Interface

Clock

Divider

SPI Bus

Cycle

Controller

Data Buffer

DIV

Clock Edge

Select

Data

CHAR_LEN

LSB

SPIMISO

SPIMOSI

SPICLK

Select

Latch

SPISEL [2..0]

16 MHz

Signal

DIO Assignment

Standard pins

Alternative pins

SPISEL1

SPISEL2

The Serial Peripheral Interface (SPI) allows high-speed synchronous data transfer between the JN5142 and peripheral devices. The JN5142 operates as a master on the SPI bus and all other devices connected to the SPI are expected to be slave devices under the control of the JN5142 CPU. The SPI includes the following features:

 Full-duplex, three-wire synchronous data transfer

 Programmable bit rates (up to 16Mbit/s)

 Programmable transaction size up to 32-bits

 Standard SPI modes 0,1,2 and 3

 Manual or Automatic slave select generation (up to 3 slaves)

 Maskable transaction complete interrupt

 LSB First or MSB First Data Transfer

 Supports delayed read edges

Figure 23: SPI Block Diagram

The SPI bus employs a simple shift register data transfer scheme. Data is clocked out of and into the active devices in a first-in, first-out fashion allowing SPI devices to transmit and receive data simultaneously.

There are three dedicated pins SPICLK, SPIMOSI, SPIMISO that are shared across all devices on the bus. MasterOut-Slave-In or Master-In-Slave-Out data transfer is relative to the clock signal SPICLK generated by the JN5142.

The JN5142 provides three slave selects, SPISEL0 to SPISEL2 to allow three SPI peripherals on the bus. SPISEL0 is a dedicated pin; this is generally connected to a serial Flash/EEPROM memory holding application code that is downloaded to internal RAM via software from reset. SPISEL1 is accessed, depending upon the configuration, on DIO0 or DIO14. SPISEL2 is accessed on DIO1 or DIO15. This is enabled under software control. The following table details which DIO are used for the SPISEL signals depending upon the configuration.

Table 3: SPISEL IO

The interface can transfer from 1 to 32-bits without software intervention and can keep the slave select lines asserted between transfers when required, to enable longer transfers to be performed.

When the device reset is active, the three outputs SPISEL, SPICLK and SPI_MOSI are tri-stated and SPI_MISO is set to be an input. The pull-up resistors associated with all four pins will be active at this time.

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Slave 0

Flash/

EEPROM

Memory

JN5142

SPISEL0

SPISEL1

SPIMOSI

SPICLK

SPIMISO

Slave 1

User

Defined

Slave 2

User

Defined

SPISEL2

SPICLK

Mode

Description

Polarity

(CPOL)

Phase

(CPHA)

SPICLK is low when idle – the first edge is positive. Valid data is output on SPIMOSI before the first clock and changes every

negative edge. SPIMISO is sampled every positive edge.

SPICLK is low when idle – the first edge is positive. Valid data is output on SPIMOSI every positive edge. SPIMISO is sampled every

negative edge.

SPICLK is high when idle – the first edge is negative. Valid data is output on SPIMOSI before the first clock edge and is changed

every positive edge. SPIMISO is sampled every negative edge.

SPICLK is high when idle – the first edge is negative. Valid data is output on SPIMOSI every negative edge. SPIMISO is sampled

every positive edge.

Figure 24: Typical JN5142 SPI Peripheral Connection

The data transfer rate on the SPI bus is determined by the SPICLK signal. The JN5142 supports transfers at selectable data rates from 16MHz to 125kHz selected by a clock divider. Both SPICLK clock phase and polarity are configurable. The clock phase determines which edge of SPICLK is used by the JN5142 to present new data on the SPIMOSI line; the opposite edge will be used to read data from the SPIMISO line. The interface should be configured appropriately for the SPI slave being accessed.

Table 4: SPI Configurations

If more than one SPISEL line is to be used in a system they must be used in numerical order starting from SPISEL0. A SPISEL line can be automatically de-asserted between transactions if required, or it may stay asserted over a

by continually providing SPICLK transitions, the ability for the select line to stay asserted is an advantage since it keeps the slave enabled over the whole of the transfer.

number of transactions. For devices such as memories where a large amount of data can be received by the master

A transaction commences with the SPI bus being set to the correct configuration, and then the slave device is selected. Upon commencement of transmission (1 to 32 bits) data is placed in the FIFO data buffer and clocked out, at the same time generating the corresponding SPICLK transitions. Since the transfer is full-duplex, the same number of data bits is being received from the slave as it transmits. The data that is received during this transmission can be read (1 to 32 bits). If the master simply needs to provide a number of SPICLK transitions to allow data to be

36 JN-DS-JN5142 1v0 © NXP Laboratories UK 2012

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sent from a slave, it should perform transmit using dummy data. An interrupt can be generated when the transaction

1 2 3 4 5 6 7

Instruction (0x03)

23 22 21 3 2 1 0

8 9 10 28 29 30 31

24-bit Address

MSB

Instruction Transaction

7 6 5 4 3 2 1 0

MSB

1 2 3 4

5 7 8N-1

3 2 1 0

LSB

Read Data Bytes Transaction(s) 1-N

SPISEL

SPICLK

SPIMOSI

SPIMISO

SPISEL

SPICLK

SPIMOSI

SPIMISO

8 9 10

7 6 5

MSB

Byte 1 Byte 2 Byte N

value unused by peripherals

has completed or alternatively the interface can be polled. If a slave device wishes to signal the JN5142 indicating that it has data to provide, it may be connected to one of the

DIO pins that can be enabled as an interrupt. Figure 25 shows a complex SPI transfer, reading data from a FLASH device, that can be achieved using the SPI

master interface. The slave select line must stay low for many separate SPI accesses, and therefore manual slave select mode must be used. The required slave select can then be asserted (active low) at the start of the transfer. A sequence 8 and 32 bit transfers can be used to issue the command and address to the FLASH device and then to read data back. Finally, the slave select can be deselected to end the transaction.

Figure 25: Example SPI Waveforms – Reading from FLASH Device using Mode 0

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D Q

Rise

Fall

Delta Sigma

Interrupt

Generator

Counter

Interrupt Enable

Capture

Generator

Prescaler

SYSCLK

TIMxCK_GT

TIMxCAP

Interrupt

PWM/DS

Reset

Generator

Edge Select

TIMxOut

Reset

System

Reset

Single

Shot

-1

11 Timers

11.1 Peripheral Timer/Counters

A general-purpose timer/counter unit, Timer0, is available that can be configured to operate in one of five possible modes. This has:

 5-bit prescaler, divides system clock by 2  Clocked from internal system clock (16MHz)  16-bit counter, 16-bit Rise and Fall (period) registers  Timer: can generate interrupts off Rise and Fall counts. Can be gated by external signal  Counter: counts number of transitions on external event signal. Can use low-high, high-low or both

transitions

 PWM/Single pulse: outputs repeating Pulse Width Modulation signal or a single pulse. Can set period and

mark-space ratio

 Capture: measures times between transitions of an applied signal  Delta-Sigma: Return-To-Zero (RTZ) and Non-Return-to-Zero (NRZ) modes  Timer usage of external IO can be controlled on a pin by pin basis

Three further timers are also available that support the same functionality but have no Counter or Capture mode. Additionally, is not possible to gate these three timers with an external signal.

prescale value

as the clock to the timer (prescaler range is 0 to 16)

38 JN-DS-JN5142 1v0 © NXP Laboratories UK 2012

Figure 26: Timer Unit Block Diagram

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Signal

DIO Assignment

Standard pins

Alternative pins

TIM0CK_GT

TIM0CAP

TIM0OUT

PWM1

PWM2

PWM3

Rise

Fall

The clock source for the Timer0 unit is fed from the 16MHz system clock. This clock passes to a 5-bit prescaler where a value of 0 leaves the clock unmodified and other values divide it by 2 value of 2 applied to the 16MHz system clock source results in a timer clock of 4MHz.

The counter is optionally gated by a signal on the clock/gate input (TIM0CK_GT). If the gate function is selected, then the counter is frozen when the clock/gate input is high.

An interrupt can be generated whenever the counter is equal to the value in either of the High or Low registers. The internal Output Enable (OE) signal enables or disables the timer output. Timer0 can be accessed, depending upon the configuration, on DIO8 to DIO10 or DIO2 to DIO4. PWM1,2,3 can be

accessed on DIO11 to DIO13 or DIO5 to DIO7. This is enabled under software control. Timer0 can be assigned to its alternative location without moving the PWMs, and vice-versa. The following table details which DIO are used for the PWM depending upon the configuration.

Table 5: Timer and PWM IO

If operating in timer mode it is not necessary to use any of the DIO pins, allowing the standard DIO functionality to be available to the application.

prescale

value. For example, a prescale

11.1.1 Pulse Width Modulation Mode

Pulse Width Modulation (PWM) mode, as used by PWM timers 1,2 and 3 and optionally by Timer0, allows the user to specify an overall cycle time and pulse length within the cycle. The pulse can be generated either as a single shot or as a train of pulses with a repetition rate determined by the cycle time.

In this mode, the cycle time and low periods of the PWM output signal can be set by the values of two independent 16-bit registers (Fall and Rise). The counter increments and its output is compared to the 16-bit Rise and Fall registers. When the counter is equal to the Rise register, the PWM output is set to high; when the counter reaches the Fall value, the output returns to low. In continuous mode, when the counter reaches the Fall value, it will reset and the cycle repeats. The PWM waveform is available on PWM1,2,3 or TIM0OUT when the output driver is enabled.

Figure 27: PWM Output Timings

11.1.2 Capture Mode

The capture mode can be used to measure the time between transitions of a signal applied to the capture input (TIM0CAP). When the capture is started, on the next low-to-high transition of the captured signal, the count value is stored in the Rise register, and on the following high-to-low transition, the counter value is stored in the Fall register. The pulse width is the difference in counts in the two registers multiplied by the period of the prescaled clock. Upon reading the capture registers the counter is stopped. The values in the High and Low registers will be updated whenever there is a corresponding transition on the capture input, and the value stored will be relative to when the

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CLK

CAPT

x 14

RISE

FALL

Rise

Fall

5 43

Capture Mode Enabled

mode was started. Therefore, if multiple pulses are seen on TIM0CAP before the counter is stopped only the last pulse width will be stored.

Figure 28: Capture Mode

11.1.3 Counter/Timer Mode

The counter/timer can be used to generate interrupts, based on the timers or event counting, for software to use. As a timer the clock source is from the system clock, prescaled if required. The timer period is programmed into the Fall register and the Fall register match interrupt enabled. The timer is started as either a single-shot or a repeating timer, and generates an interrupt when the counter reaches the Fall register value.

When used to count external events on TIM0CK_GT the clock source is selected from the input pin and the number of events programmed into the Fall register. The Fall register match interrupt is enabled and the counter started, usually in single shot mode. An interrupt is generated when the programmed number of transitions is seen on the input pin. The transitions counted can configured to be rising, falling or both rising and falling edges.

Edges on the event signal must be at least 100nsec apart, i.e. pulses must be wider than 100nsec.

11.1.4 Delta-Sigma Mode

A separate delta-sigma mode is available, allowing a low speed delta-sigma DAC to be implemented with up to 16-bit resolution. This requires that a resistor-capacitor network is placed between the output DIO pin and digital ground. A stream of pulses with digital voltage levels is generated which is integrated by the RC network to give an analogue voltage. A conversion time is defined in terms of a number of clock cycles. The width of the pulses generated is the period of a clock cycle. The number of pulses output in the cycle, together with the integrator RC values, will determine the resulting analogue voltage. For example, generating approximately half the number of pulses that make up a complete conversion period will produce a voltage on the RC output of VDD1/2, provided the RC time constant is chosen correctly. During a conversion, the pulses will be pseudo-randomly dispersed throughout the cycle in order to produce a steady voltage on the output of the RC network.

The output signal is asserted for the number of clock periods defined in the High register, with the total period being 216 cycles. For the same value in the High register, the pattern of pulses on subsequent cycles is different, due to the pseudo-random distribution.

The delta-sigma converter output can operate in a Return-To-Zero (RTZ) or a Non-Return-to-Zero (NRZ) mode. The NRZ mode will allow several pulses to be output next to each other. The RTZ mode ensures that each pulse is separated from the next by at least one period. This improves linearity if the rise and fall times of the output are different to one another. Essentially, the output signal is low on every other output clock period, and the conversion cycle time is twice the NRZ cycle time i.e. 217 clocks. The integrated output will only reach half VDD2 in RTZ mode, since even at full scale only half the cycle contains pulses. Figure 29 and Figure 30 illustrate the difference between RTZ and NRZ for the same programmed number of pulses.

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1 2 3 1 2 N

Conversion cycle 1

Conversion cycle 2

1 2 3 1 2 N

Conversion cycle 1

N 3

Conversion cycle 2

JN5142

PWM1

Timer0

CLK/GATE

CAPTURE

PWM

Tacho

1N4007

+12V

IRF521

1 pulse/rev

Figure 29: Return To Zero Mode in Operation

Figure 30: Non-Return to Zero Mode

11.1.5 Example Timer/Counter Application

Figure 31 shows an application of the JN5142 timers to provide closed loop speed control. Timer 0 is configured in PWM mode to provide a variable mark-space ratio switching waveform to the gate of the NFET. This in turn controls the power in the DC motor.

Timer 1 is configured to count the rising edge events on the clk/gate pin over a constant period. This converts the tacho pulse stream output into a count proportional to the motor speed. This value is then used by the application software executing the control algorithm.

If required for other functionality, then the unused IO associated with the timers could be used as general purpose DIO.

Figure 31: Closed Loop PWM Speed Control Using JN5142 Timers

11.2 Tick Timer

The JN5142 contains a hardware timer that can be used for generating timing interrupts to software. It may be used to implement regular events such as ticks for software timers or an operating system, as a high-precision timing reference or can be used to implement system monitor timeouts as used in a watchdog timer. Features include:

 32-bit counter

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Match Value

Counter

Mode

Control

SysClk

Run

Match

Int

Enable

Tick Timer

Interrupt

Reset

Mode

 28-bit match value  Maskable timer interrupt  Single-shot, Restartable or Continuous modes of operation

Figure 32: Tick Timer

The Tick Timer is clocked from a continuous 16MHz clock, which is fed to a 32-bit wide resettable up-counter, gated by a signal from the mode control block. A match register allows comparison between the counter and a programmed value. The match value, measured in 16MHz clock cycles is programmed through software, in the range 0 to 0x0FFFFFFF. The output of the comparison can be used to generate an interrupt if the interrupt is enabled and used in controlling the counter in the different modes. Upon configuring the timer mode, the counter is also reset.

If the mode is programmed as single shot, the counter begins to count from zero until the match value is reached. The match signal will be generated which will cause an interrupt if enabled, and the counter will stop counting. The counter is restarted by reprogramming the mode.

If the mode is programmed as restartable, the operation of the counter is the same as for the single shot mode, except that when the match value is reached the counter is reset and begins counting from zero. An interrupt will be generated when the match value is reached if it is enabled.

Continuous mode operation is similar to restartable, except that when the match value is reached, the counter is not reset but continues to count. An interrupt will be generated when the match value is reached if enabled.

11.3 Wakeup Timers

Two 35-bit wakeup timers are available in the JN5142 driven from the 32kHz internal clock. They may run during sleep periods when the majority of the rest of the device is powered down, to time sleep periods or other long period timings that may be required by the application. The wakeup timers do not run during deep sleep and may optionally be disabled in sleep mode through software control. When a wakeup timer expires it typically generates an interrupt, if the device is asleep then the interrupt may be used as an event to end the sleep period. See Section 18 for further details on how they are used during sleep periods. Features include:

 35-bit down-counter  Optionally runs during sleep periods  Clocked by 32kHz system clock; either 32kHz RC oscillator, 32kHz XTAL oscillator or 32kHz clock input

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A wakeup timer consists of a 35-bit down counter clocked from the selected 32 kHz clock. An interrupt or wakeup event can be generated when the counter reaches zero. On reaching zero the counter will continue to count down until stopped, which allows the latency in responding to the interrupt to be measured. If an interrupt or wakeup event is required, the timer interrupt should be enabled before loading the count value for the period. Once the count value is loaded and counter started, the counter begins to count down; the counter can be stopped at any time through software control. The counter will remain at the value it contained when the timer was stopped and no interrupt will be generated. The status of the timers can be read to indicate if the timers are running and/or have expired; this is useful when the timer interrupts are masked. This operation will reset any expired status flags.

11.3.1 RC Oscillator Calibration

The RC oscillator that can be used to time sleep periods is designed to require very little power to operate and be self-contained, requiring no external timing components and hence is lower cost. As a consequence of using on-chip resistors and capacitors, the inherent absolute accuracy and temperature coefficient is lower than that of a crystal oscillator, but once calibrated the accuracy approaches that of a crystal oscillator. Sleep time periods should be as close to the desired time as possible in order to allow the device to wake up in time for important events, for example beacon transmissions in the IEEE802.15.4 protocol. If the sleep time is accurate, the device can be programmed to wake up very close to the calculated time of the event and so keep current consumption to a minimum. If the sleep time is less accurate, it will be necessary to wake up earlier in order to be certain the event will be captured. If the device wakes earlier, it will be awake for longer and so reduce battery life.

In order to allow sleep time periods to be as close to the desired length as possible, the true frequency of the RC oscillator needs to be determined to better than the initial 30% accuracy. The calibration factor can then be used to calculate the true number of nominal 32kHz periods needed to make up a particular sleep time. A calibration reference counter, clocked from the 16MHz system clock, is provided to allow comparisons to be made between the 32kHz RC clock and the 16MHz system clock when the JN5142 is awake.

Wakeup timer0 counts for a set number of 32kHz clock periods during which time the reference counter runs. When the wakeup timer reaches zero the reference counter is stopped, allowing software to read the number of 16MHz clock ticks generated during the time represented by the number of 32kHz ticks programmed in the wakeup timer. The true period of the 32kHz clock can thus be determined and used when programming a wakeup timer to achieve a better accuracy and hence more accurate sleep periods

For a RC oscillator running at exactly 32,000Hz the value returned by the calibration procedure should be 10000, for a calibration period of twenty 32,000Hz clock periods. If the oscillator is running faster than 32,000Hz the count will be less than 10000, if running slower the value will be higher. For a calibration count of 9000, indicating that the RC oscillator period is running at approximately 35kHz, to time for a period of 2 seconds the timer should be loaded with 71,111 ((10000/9000) x (32000 x 2)) rather than 64000.

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12 Pulse Counters

Two 16-bit counters are provided that can increment during all modes of operation (including sleep). The first, PC0, increments from pulses received on DIO1. The other pulse counter, PC1, can also be accessed on DIO5 or DIO8 depending upon the configuration. This is enabled under software control. The pulses can be de-bounced using the 32kHz clock to guard against false counting on slow or noisy edges. Increments occur from a configurable rising or falling edge on the respective DIO input.

Each counter has an associated 16-bit reference that is loaded by the user. An interrupt (and wakeup event if asleep) may be generated when a counter reaches its pre-configured reference value. The two counters may optionally be cascaded together to provide a single 32-bit counter, linked to DIO1. The counters do not saturate at 65535, but naturally roll-over to 0. Additionally, the pulse counting continues when the reference value is reached without software interaction so that pulses are not missed even if there is a long delay before an interrupt is serviced or during the wakeup process.

The system can work with signals up to 100kHz, with no debounce, or from 5.3kHz to 1.7kHz with debounce. When using debounce the 32kHz clock must be active, so for minimum sleep currents the debounce mode should not be used.

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13 Serial Communications

Processor Bus

Divisor

Latch

Registers

Line

Status

Line

Control

FIFO

Control

Receiver FIFO

Transmitter FIFO

Baud Generator

Logic

Transmitter Shift

Receiver Shift

Transmitter

Logic

Receiver

Logic

RXD

TXD

Modem Control

Modem

Status

Modem Signals

Logic

RTS CTS

Interrupt

Enable

Interrupt

Logic

Internal

Interrupt

The JN5142 has a Universal Asynchronous Receiver/Transmitter (UART) serial communication interface. It provides similar operating features to the industry standard 16550A device operating in FIFO mode. The interface performs serial-to-parallel conversion on incoming serial data and parallel-to-serial conversion on outgoing data from the CPU to external devices. In both directions, a 16-byte deep FIFO buffer allows the CPU to read and write multiple characters on each transaction. This means that the CPU is freed from handling data on a character-by-character basis, with the associated high processor overhead. The UART has the following features:

 Emulates behaviour of industry standard NS16450 and NS16550A UARTs  16 byte transmit and receive FIFO buffers reduce interrupts to CPU, with direct access to fill levels of each  Adds/deletes standard start, stop and parity communication bits to or from the serial data  Independently controlled transmit, receive, status and data sent interrupts  Optional modem flow control signals CTS and RTS  Fully programmable data formats: baud rate, start, stop and parity settings  False start bit detection, parity, framing and FIFO overrun error detect and break indication  Internal diagnostic capabilities: loop-back controls for communications link fault isolation  Flow control by software or automatically by hardware

The serial interface contains programmable fields that can be used to set number of data bits (5, 6,7 or 8), even, odd, set-at-1, set-at-0 or no-parity detection and generation of single or multiple stop bit, (for 5 bit data, multiple is 1.5 stop bits; for 6, 7 or 8 data bits, multiple is 2 bits).

The baud rate is programmable up to 1Mbps, standard baud rates such as 4800, 9600, 19.2k, 38.4k etc. can be configured.

For applications requiring hardware flow control, two control signals are provided: Clear-To-Send (CTS) and Request-

Figure 33: UART Block Diagram

To-Send (RTS). CTS is an indication sent by an external device to the UART that it is ready to receive data. RTS is an indication sent by the UART to the external device that it is ready to receive data. RTS is controlled from software, while the value of CTS can be read. Monitoring and control of CTS and RTS is a software activity, normally performed as part of interrupt processing. The signals do not control parts of the UART hardware, but simply indicate to software the state of the UART external interface. Alternatively, the Automatic Flow Control mode can be set

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Signal

DIO Assignment

Standard pins

Alternative pins

CTS0

RTS0

TXD0

RXD0

where the hardware controls the value of the generated RTS (negated if the receive FIFO fill level is greater than a programmable threshold of 8, 11, 13 or 15 bytes), and only transmits data when the incoming CTS is asserted.

Software can read characters, one byte at a time, from the Receive FIFO and can also write to the Transmit FIFO, one byte at a time. The Transmit and Receive FIFOs can be cleared and reset independently of each other. The status of the transmitter can be checked to see if it is empty, and if there is a character being transmitted. The status of the receiver can also be checked, indicating if conditions such as parity error, framing error or break indication have occurred. It also shows if an overrun error occurred (receive buffer full and another character arrives) and if there is data held in the receive FIFO.

The UART is accessed, depending upon the configuration, on DIO4 to DIO7 or DIO12 to DIO15. This is enabled under software control. The following table details which DIO are used for the UART depending upon the configuration.

Table 6: UART IO

If CTS and RTS are not required on the device‟s external pins, then they may be disabled, this allows the DIOx

function to be used for other purposes. Note: With the automatic flow control threshold set to 15, the hardware flow control within the UART block negates

RTS when the receive FIFO is about to become full. In some instances it has been observed that remote devices that are transmitting data do not respond quickly enough to the de-asserted CTS and continue to transmit data. In these instances the data will be lost in a receive FIFO overflow.

13.1 Interrupts

Interrupt generation can be controlled for the UART block, and is divided into four categories:  Received Data Available: Is set when data in the Rx FIFO queue reaches a particular level (the trigger level can

be configured as 1, 4, 8 or 14) or if no character has been received for 4 character times.

 Transmit FIFO Empty: set when the last character from the Tx FIFO is read and starts to be transmitted.  Receiver Line Status: set when one of the following occur (1) Parity Error - the character at the head of the

receive FIFO has been received with a parity error, (2) Overrun Error - the Rx FIFO is full and another character

has been received at the Receiver shift register, (3) Framing Error - the character at the head of the receive

FIFO does not have a valid stop bit and (4) Break Interrupt – occurs when the RxD line has been held low for an

entire character.  Modem Status: Generated when the CTS (Clear To Send) input control line changes.

13.2 UART Application

The following example shows the UART connected to a 9-pin connector compatible with a PC. As the JN5142 device pins do not provide the RS232 line voltage, a level shifter is used.

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JN5142

RTS

CTS

TXD

RXD

UART0

RS232

Level

Shifter

1 2 3 4 5 6 7 8 9

CD RD TD

DTR

SG DSR RTS CTS

PC COM Port

Pin Signal

Figure 34: JN5142 Serial Communication Link

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Signal

DIO Assignment

Standard pins

Alternative pins

clock (TCK)

control (TMS)

data out (TDO)

data in (TDI)

14 JTAG Debug Interface

The JN5142 includes an IEEE1149.1 compliant JTAG port for the sole purpose of software code debug with the Software Development Kit. The JTAG interface is disabled by default and is enabled under software control. Therefore, debugging is only possible if enabled by the application. Once enabled, the application executes as normal until the external debugger controller initiates debug activity.

The Debugger supports breakpoints and watchpoints based on four comparisons between any of program counter, load/store effective address and load/store data. There is the ability to chain the comparisons together. There is also the ability, under debugger control to perform the following commands: go, stop, reset, step over/into/out/next, run to cursor and breakpoints. In addition, under control of the debugger, it is possible to:

 Read and write registers on the wishbone bus  Read ROM and RAM, and write to RAM  Read and write CPU internal registers

The Debugger interface is accessed, depending upon the configuration, through the standard or alternative pins used for UART0. This is enabled under software control and is dealt with in [4]. The following table details which DIO are used for the JTAG interface depending upon the configuration.

Table 7: Hardware Debugger IO

If doze mode is active when debugging is started, the processor will be woken and then respond to debugger commands. It is not possible to wake the device from sleep using the debug interface and debugging is not available while the device is sleeping.

When using the debug interface, program execution is halted, and control of the CPU is handed to the debugger. The watchdog, tick timer and the timers described in Section 11 are stalled while the debugger is in control of the CPU.

When control is handed from the CPU to the debugger or back a small number of CPU clock cycles are taken flushing or reloading the CPU pipeline. Because of this, when a program is halted by the debugger and then restarted again, a small number of tick timer cycles will elapse.

It is possible to prevent all hardware debugging by blowing the relevant Efuse bit. For further information on how to program the eFuse, please contact technical support via the on-line tech-support system.

The JTAG interface does not support boundary scan testing. It is recommended that the JN5142 is not connected as part of the board scan chain.

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15 Two-Wire Serial Interface (I2C)

Signal

DIO Assignment

Standard pins

Alternative pins

SIF_CLK

SIF_D

The JN5142 includes industry standard I2C two-wire synchronous Serial Interface operates as a Master (MSIF) or Slave (SSIF) that provides a simple and efficient method of data exchange between devices. The system uses a serial data line (SIF_D) and a serial clock line (SIF_CLK) to perform bi-directional data transfers and includes the following features:

Common to both master and slave:

 Compatible with both I2C and SMbus peripherals  Support for 7 and 10-bit addressing modes  Optional pulse suppression on signal inputs

Master only:

 Multi-master operation  Software programmable clock frequency  Clock stretching and wait state generation  Software programmable acknowledge bit  Interrupt or bit-polling driven byte-by-byte data-transfers  Bus busy detection

Slave only:

 Programmable slave address  Simple byte level transfer protocol  Write data flow control with optional clock stretching or acknowledge mechanism  Read data preloaded or provided as required

The Serial Interface is accessed, depending upon the configuration, DIO14 and DIO15 or DIO16 and DIO17. This is enabled under software control. The following table details which DIO are used for the Serial Interface depending upon the configuration.

Table 8: Two-Wire Serial Interface IO

15.1 Connecting Devices

The clock and data lines, SIF_D and SIF_CLK, are alternate functions of DIO15 and DIO14 respectively. The serial interface function of these pins is selected when the interface is enabled. They are both bi-directional lines, connected internally to the positive supply voltage via weak (45k) programmable pull-up resistors. However, it is recommended that external 4.7k pull-ups be used for reliable operation at high bus speeds, as shown in Figure 35. When the bus is free, both lines are HIGH. The output stages of devices connected to the bus must have an opendrain or open-collector in order to perform the wired-AND function. The number of devices connected to the bus is solely dependent on the bus capacitance limit of 400pF.

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SIF_CLK SIF_D

VDD

D1_OUT

D1_IN CLK1_IN

CLK1_OUT

D2_IN CLK2_IN

CLK2_OUT

DEVICE 1 DEVICE 2

Pullup Resistors

D2_OUT

JN5142

SIF

DIO14

DIO15

SIF_CLK

Master SIF_CLK

Slave SIF_CLK

Wired-AND SIF_CLK

Clock held low

by Slave

Figure 35: Connection Details

15.2 Clock Stretching

Slave devices can use clock stretching to slow down the transfer bit rate. After the master has driven SIF_CLK low,

the slave can drive SIF_CLK low for the required period and then release it. If the slave‟s SIF_CLK low period is

greater than the master‟s low period the resulting SIF_CLK bus signal low period is stretched thus inserting wait

states.

Figure 36: Clock Stretching

15.3 Master Two-wire Serial Interface

When operating as a master device, it provides the clock signal and a prescale register determines the clock rate, allowing operation up to 400kbit/s.

Data transfer is controlled from the processor bus interface at a byte level, with the processor responsible for indicating when start, stop, read, write and acknowledge control should be generated. Write data written into a transmit buffer will be written out across the two-wire interface when indicated, and read data received on the interface is made available in a receive buffer. Indication of when a particular transfer has completed may be indicated by means of an interrupt or by polling a status bit.

The first byte of data transferred by the device after a start bit is the slave address. The JN5142 supports both 7-bit and 10-bit slave addresses by generating either one or two address transfers. Only the slave with a matching address will respond by returning an acknowledge bit.

The master interface provides a true multi-master bus including collision detection and arbitration that prevents data corruption. If two or more masters simultaneously try to control the bus, a clock synchronization procedure determines the bus clock. Because of the wired-AND connection of the interface, a high-to-low transition on the bus affects all connected devices. This means a high-to-low transition on the SIF_CLK line causes all concerned devices to count off their low period. Once the clock input of a device has gone low, it will hold the SIF_CLK line in that state until the clock high state is reached when it releases the SIF_CLK line. Due to the wired-AND connection, the SIF_CLK line will therefore be held low by the device with the longest low period, and held high by the device with the shortest high period.

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SIF_CLK1

SIF_CLK2

SIF_CLK

Master1 SIF_CLK

Master2 SIF_CLK

Wired-AND SIF_CLK

Start counting

low period

Start counting

high period

Wait

State

Figure 37: Multi-Master Clock Synchronisation

After each transfer has completed, the status of the device must be checked to ensure that the data has been acknowledged correctly, and that there has been no loss of arbitration. (N.B. Loss of arbitration may occur at any point during the transfer, including data cycles). An interrupt will be generated when arbitration has been lost.

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Address

Name

Behaviour

0000 000

General Call/Start Byte

Ignored

0000 001

CBUS address

Ignored

0000 010

Reserved

Ignored

0000 011

Reserved

Ignored

0000 1XX

Hs-mode master code

Ignored

1111 1XX

Reserved

Ignored

1111 0XX

10-bit address

Only responded to if 10 bit address set in address register

15.4 Slave Two-wire Serial Interface

When operating as a slave device, the interface does not provide a clock signal, although it may drive the clock signal low if it is required to apply clock stretching.

Only transfers whose address matches the value programmed into the interface‟s address register are accepted. The

interface allows both 7 and 10 bit addresses to be programmed, but only responds with an acknowledge to a single

address. Addresses defined as “reserved” will not be responded to, and should not be programmed into the address

Table 9 : List of two-wire serial interface reserved addresses

Data transfer is controlled from the processor bus interface at a byte level, with the processor responsible for taking write data from a receive buffer and providing read data to a transmit buffer when indicated. A series of interrupt status bits are provided to control the flow of data.

For writes, in to the slave interface, it is important that data is taken from the receive buffer by the processor before the next byte of data arrives. To enable this, the interface may be configured to work in two possible backoff modes:

 Not Acknowledge mode – where the interface returns a Not Acknowledge (NACK) to the master if more data

is received before the previous data has been taken. This will lead to the termination of the current data transfer.

 Clock Stretching mode – where the interface holds the clock line low until the previous data has been taken.

This will occur after transfer of the next data but before issuing an acknowledge

For reads, from the slave interface, the data may be preloaded into the transmit buffer when it is empty (i.e. at the start of day, or when the last data has been read), or fetched each time a read transfer is requested. When using data preload, read data in the buffer must be replenished following a data write, as the transmit and received data is contained in a shared buffer. The interface will hold the bus using clock stretching when the transmit buffer is empty.

Interrupts may be triggered when:

 Data Buffer read data is required – a byte of data to be read should be provided to avoid the interface from

clock stretching

 Data Buffer read data has been taken – this indicates when the next data may be preloaded into the data

buffer

 Data Buffer write data is available – a byte of data should be taken from the data buffer to avoid data backoff

as defined above

 The last data in a transfer has completed – i.e. the end of a burst of data, when a Stop or Restart is seen  A protocol error has been spotted on the interface

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16 Random Number Generator

A random number generator is provided which creates a 16-bit random number each time it is invoked. Consecutive calls can be made to build up any length of random number required. Each call takes approximately 0.25msec to complete. Alternatively, continuous generation mode can be used where a new number is generated approximately every 0.25msec. In either mode of operation an interrupt can be generated to indicate when the number is available, or a status bit can be polled.

The random bits are generated by sampling the state of the 32MHz clock every 32kHz system clock edge. As these clocks are asynchronous to each other, each sampled bit is unpredictable and hence random.

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ADC

Supply Voltage

(VDD1)

Comparator 1

COMP1M (DIO17)

COMP1P (DIO16)

ADC1

VREF/ADC2

ADC3 (DIO0)

ADC4 (DIO1)

Vref

Internal Reference Vref Select

Chip Boundary

Temp

Sensor

17 Analogue Peripherals

The JN5142 contains a number of analogue peripherals allowing the direct connection of a wide range of external sensors and switches.

Figure 38: Analogue Peripherals

In order to provide good isolation from digital noise, the analogue peripherals and radio are powered by the radio regulator, which is supplied from the analogue supply VDD1 and referenced to analogue ground VSSA.

A reference signal Vref for the ADC can be selected between an internal bandgap reference or an external voltage reference supplied to the VREF pin. ADC input 2 cannot be used if an external reference is required as this uses the same pin as VREF. Note also that ADC3 and ADC4 use the same pins as DIO0/SPISEL1 and DIO1/SPISEL2 respectively. These pins can only be used for the ADC if they are not required for their alternative functions. Similarly, the comparator inputs are shared with DIO16/SIF_CLK and DIO17/SIF_D. If used for their analogue functions, these DIOs must be put into a passive state by setting them to Inputs with their pull-ups disabled.

The ADC is clocked from a common clock source derived from the 16MHz clock

17.1 Analogue to Digital Converter

The 8-bit analogue to digital converter (ADC) uses a successive approximation design to perform high accuracy conversions as typically required in wireless sensor network applications. It has six multiplexed single-ended input channels: four available externally, one connected to an internal temperature sensor, and one connected to an internal supply monitoring circuit.

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17.1.1 Operation

VREF

Gain Setting

Maximum Input Range

Supply Voltage Range (VDD)

1.2V

1.6V

1.2V

1.6V

0 0 1 1

1.2V

1.6V

2.4V

3.2V

2.2V - 3.6V

2.6V - 3.6V

3.4V - 3.6V

ADC

5 K

8 pF

Sample

Switch

ADC front

end

The input range of the ADC can be set between 0V to either the reference voltage or twice the reference voltage. The reference can be either taken from the internal voltage reference or from the external voltage applied to the VREF pin. For example, an external reference of 1.2V supplied to VREF may be used to set the ADC range between 0V and 2.4V.

Table 10: ADC Maximum Input Range

The input clock to the ADC is 16MHz and can be divided down to 2MHz, 1MHz, 500kHz and 250kHz. During an ADC conversion the selected input channel is sampled for a fixed period and then held. This sampling period is defined as a number of ADC clock periods and can be programmed to 2, 4, 6 or 8. The conversion rate is ((3 x Sample period) + 10) clock periods. For example for 500kHz conversion with sample period of 2 will be (3 x 2) + 10 = 16 clock periods, 32µsecs or 31.25kHz. The ADC can be operated in either a single conversion mode or alternatively a new conversion can be started as soon as the previous one has completed, to give continuous conversions.

If the source resistance of the input voltage is 1kΩ or less, then the default sampling time of 2 clocks should be used. The input to the ADC can be modelled as a resistor of 5kΩ(typ) and 10kΩ (max) to represent the on-resistance of the switches and the sampling capacitor 8pF. The sampling time required can then be calculated, by adding the sensor source resistance to the switch resistance, multiplying by the capacitance giving a time constant. Assuming normal exponential RC charging, the number of time constants required to give an acceptable error can be calculated, 6 time constants gives an error of 0.25%, so for 8-bit accuracy 7 time constants should be the target. For a source with zero resistance, 7 time constants is 560 nsecs, hence the smallest sampling window of 2 clock periods can be used.

The ADC sampling period, input range and mode (single shot or continuous) are controlled through software. When the ADC conversion is complete, an interrupt is generated. Alternatively the conversion status can be polled.

When operating in continuous mode, it is recommended that the interrupt is used to signal the end of a conversion, since conversion times may range from 8 to 136 secs. Polling over this period would be wasteful of processor bandwidth.

To facilitate averaging of the ADC values, which is a common practice in microcontrollers, a dedicated accumulator has been added, the user can define the accumulation to occur over 2,4,8 or 16 samples. The end of conversion interrupt can be modified to occur at the end of the chosen accumulation period, alternatively polling can still be used. Software can then be used to apply the appropriate rounding and shifting to generate the average value, as well as setting up the accumulation function.

For detailed electrical specifications, see Section 19.3.6.

Figure 39: ADC Input Equivalent Circuit

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17.1.2 Supply Monitor

The internal supply monitor allows the voltage on the analogue supply pin VDD1 to be measured. This is achieved with a potential divider that reduces the voltage by a factor of 0.666, allowing it to fall inside the input range of the ADC when set with an input range twice the internal voltage reference. The resistor chain that performs the voltage reduction is disabled until the measurement is made to avoid a continuous drain on the supply.

17.1.3 Temperature Sensor

The on chip temperature sensor can be used either to provide an absolute measure of the device temperature or to detect changes in the ambient temperature. In common with most on chip temperature sensors, it is not trimmed and so the absolute accuracy variation is large; the user may wish to calibrate the sensor prior to use. The sensor forces a constant current through a forward biased diode to provide a voltage output proportional to the chip die temperature which can then be measured using the ADC. The measured voltage has a linear relationship to temperature as described in Section 19.3.12.

Because this sensor is on chip, any measurements taken must account for the thermal time constants. For example, if the device just came out of sleep mode the user application should wait until the temperature has stabilised before taking a measurement.

17.2 Comparator

The JN5142 contains one analogue comparator, COMP1, that is designed to have true rail-to-rail inputs and operate over the full voltage range of the analogue supply VDD1. The hysteresis level can be set to a nominal value of 0mV, 10mV, 20mV or 40mV. The source of the negative input signal for the comparator can be set to the internal voltage reference, the negative external pin (COMP1M, which uses the same pin as DIO17) or the positive external pin (COMP1P, on the same pin as DIO16). The source of the positive input signal can be COMP1P or COMP1M. DIO16 and DIO17 cannot be used if the external comparator inputs are needed. The comparator output is routed to an internal register and can be polled, or can be used to generate interrupts. The comparator can be disabled to reduce power consumption.

The comparator also has a low power mode where the response time of the comparator is slower than the normal mode, but the current required is greatly reduced, these figures are specified in Section 19.3.7. It is the only mode that may be used during sleep, where a transition through the threshold will wake the device. The wakeup action and the configuration for which edge of the comparator output will be active are controlled through software. In sleep mode the negative input signal source, must be configured to be driven from the external pins.

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18 Power Management and Sleep Modes

18.1 Operating Modes

Three operating modes are provided in the JN5142 that enable the system power consumption to be controlled carefully to maximise battery life.

 Active Processing Mode  Sleep Mode  Deep Sleep Mode

The variation in power consumption of the three modes is a result of having a series of power domains within the chip that may be controllably powered on or off.

18.1.1 Power Domains

The JN5142 has the following power domains:  VDD Supply Domain: supplies the wake-up timers and controller, DIO blocks, Comparator, SVM and BOR plus

Fast RC, 32kHz RC and crystal oscillators. This domain is driven from the external supply (battery) and is always powered. The wake-up timers and controller, and the 32kHz RC and crystal oscillators may be powered on or off in sleep mode through software control.

 Digital Logic Domain: supplies the digital peripherals, CPU, ROM, Baseband controller, Modem and

Encryption processor. It is powered off during sleep mode.

 RAM Domain: supplies the RAM during sleep mode to retain the memory contents. It may be powered on or

off for sleep mode through software control.

 Radio Domain: supplies the radio interface, ADCs and temperature sensor. It is powered during transmit and

receive and when the analogue peripherals are enabled. It is controlled by the baseband processor and is powered off during sleep mode.

The current consumption figures for the different modes of operation of the device is given in Section 19.2.2.

18.2 Active Processing Mode

Active processing mode in the JN5142 is where all of the application processing takes place. By default, the CPU will execute at the selected clock speed executing application firmware. All of the peripherals are available to the application, as are options to actively enable or disable them to control power consumption; see specific peripheral sections for details.

Whilst in Active processing mode there is the option to doze the CPU but keep the rest of the chip active; this is particularly useful for radio transmit and receive operations, where the CPU operation is not required therefore saving power.

18.2.1 CPU Doze

Whilst in doze mode, CPU operation is stopped but the chip remains powered and the digital peripherals continue to run. Doze mode is entered through software and is terminated by any interrupt request. Once the interrupt service routine has been executed, normal program execution resumes. Doze mode uses more power than sleep and deep sleep modes but requires less time to restart and can therefore be used as a low power alternative to an idle loop.

Whilst in CPU doze the current associated with the CPU is not consumed, therefore the basic device current is reduced as shown in the figures in Section 19.2.2.1.

18.3 Sleep Mode

The JN5142 enters sleep mode through software control. In this mode most of the internal chip functions are shutdown to save power, however the state of DIO pins are retained, including the output values and pull-up enables, and this therefore preserves any interface to the outside world.

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When entering into sleep mode, there is an option to retain the RAM contents throughout the sleep period. If the wakeup timers are not to be used for a wakeup event and the application does not require them to run continually, then power can be saved by switching off the 32kHz oscillator if selected as the 32kHz system clock through software control. The oscillator will be restarted when a wakeup event occurs.

Whilst in sleep mode one of four possible events can cause a wakeup to occur: transitions on DIO inputs, expiry of wakeup timers, pulse counters maturing or comparator events. If any of these events occur, and the relevant interrupt is enabled, then an interrupt is generated that will cause a wakeup from sleep. It is possible for multiple wakeup sources to trigger an event at the same instant and only one of them will be accountable for the wakeup period. It is therefore necessary in software to remove all other pending wakeup events prior to requesting entry back into sleep mode; otherwise, the device will re-awaken immediately.

When wakeup occurs, a similar sequence of events to the reset process described in Section 6.1 happens, including the checking of the supply voltage by the Brown Out Detector 6.4. The High-Speed RC oscillator is started up, once stable the power to CPU system is enabled and the reset is removed. Software determines that this is a reset from sleep and so commences with the wakeup process. If RAM contents were held through sleep, wakeup is quicker as the application program does not have to be reloaded from Flash memory. See Section 19.3.4 for wake-up timings.

18.3.1 Wakeup Timer Event

The JN5142 contains two 35-bit wakeup timers that are counters clocked from the 32kHz oscillator, and can be programmed to generate a wake-up event. Following a wakeup event, the timers continue to run. These timers are described in Section 11.3.

Timer events can be generated from both of the two timers; one is intended for use by the 802.15.4 protocol, the other being available for use by the Application running on the CPU. These timers are available to run at any time, even during sleep mode.

18.3.2 DIO Event

Any DIO pin when used as an input has the capability, by detecting a transition, to generate a wake-up event. Once this feature has been enabled the type of transition can be specified (rising or falling edge). Even when groups of DIO lines are configured as alternative functions such as the UARTs or Timers etc, any input line in the group can still be used to provide a wakeup event. This means that an external device communicating over the UART can wakeup a sleeping device by asserting its RTS signal pin (which is the CTS input of the JN5142).

18.3.3 Comparator Event

The comparator can generate a wakeup interrupt when a change in the relative levels of the positive and negative inputs occurs. The ability to wakeup when continuously monitoring analogue signals is useful in ultra-low power applications. For example, the JN5142 can remain in sleep mode until the voltage drops below a threshold and then be woken up to deal with the alarm condition.

18.3.4 Pulse Counter

The JN5142 contains two 16 bit pulse counters that can be programmed to generate a wake-up event. Following the wakeup event the counters will continue to operate and therefore no pulse will be missed during the wake-up process. These counters are described in Section 12.

To minimise sleep current it is possible to disable the 32K RC oscillator and still use the pulse counters to cause a wake-up event, provided debounce mode is not required.

18.4 Deep Sleep Mode

Deep sleep mode gives the lowest power consumption. All switchable power domains are off and certain functions in the VDD supply power domain, including the 32kHz oscillator are stopped. This mode can be exited by a power down, a hardware reset on the RESETN pin, or a DIO event. The DIO event in this mode causes a chip reset to occur.

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19 Electrical Characteristics

Parameter

Min

Max

Device supply voltage VDD1, VDD2

-0.3V

3.6V

Supply voltage at voltage regulator bypass pins VB_xxx

-0.3V

1.98V

Voltage on analogue pins XTALOUT, XTALIN, VCOTUNE, RF_IN.

-0.3V

VB_xxx + 0.3V

Voltage on analogue pins VREF, ADC1, IBIAS

-0.3V

VDD1 + 0.3V

Voltage on 5v tolerant digital pins SPICLK, SPIMOSI, SPIMISO, SPISEL0, DIO2-8 & DIO11-14, RESETN

-0.3V

Lower of (VDD2 + 2V)

and 5.5V

Voltage on 3v tolerant digital pins DIO0, DIO1, DIO9, DIO10, DIO15-17

-0.3V

VDD2 + 0.3V

Storage temperature

-40ºC

150ºC

Reflow soldering temperature according to IPC/JEDEC J-STD-020C

260ºC

ESD rating

Human Body Model 1

2.0kV

Charged Device Model

(Exception XTALOUT 350V )

500V

Supply

Min

Max

VDD1, VDD2

2.0V

3.6V

Standard Ambient temperature range

-40ºC

85ºC

Extended Ambient temperature range

-40ºC

125ºC

19.1 Maximum Ratings

Exceeding these conditions may result in damage to the device.

1) Testing for Human Body Model discharge is performed as specified in JEDEC Standard JESD22-A114.

2) Testing for Charged Device Model discharge is performed as specified in JEDEC Standard JESD22-C101.

19.2 DC Electrical Characteristics

19.2.1 Operating Conditions

In the following sections typical is defined as 25ºC and VDD1,2 =3V Most parameter values cover the extended temperature range up to 125 ºC, where this is not the case, two values

are given, the value in italics type face is for standard temperature range up to 85ºC and the value in bold is for the extended range.

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Mode:

Min

Typ

Max

Unit

Notes

CPU processing 32,16,8,4,2 or 1MHz

2100 +

220/MHz

µA

SPI, GPIOs enabled. When in CPU doze the current related to CPU speed is not consumed.

Radio transmit

14.8

CPU in software doze – radio transmitting

Radio receive

16.5

CPU in software doze – radio in receive mode

The following current figures should be added to those above if the feature is being used

ADC 655

µA

Temperature sensor and battery measurements require ADC

Comparator

73/0.8

µA

Normal/low-power

UART 90

µA

For each UART

Timer 30

µA

For each Timer

2-wire serial interface (I2C)

µA

Mode:

Min

Typ

Max

Unit

Notes

Sleep mode with I/O wakeup

0.12

µA

Waiting on I/O event

Sleep mode with I/O and RC Oscillator timer wakeup – measured at 25ºC

0.73

µA

As above, but also waiting on timer event. If both wakeup timers are enabled then add another 0.05µA

32kHz crystal oscillator

1.5

µA

As alternative sleep timer

The following current figures should be added to those above if the feature is being used

RAM retention– measured at 25ºC

0.7

µA

For full 32KB retained Comparator (low-power mode)

0.8

µA

Reduced response time

Mode:

Min

Typ

Max

Unit

Notes

Deep sleep mode– measured at 25ºC

100

Waiting on chip RESET or I/O event

19.2.2 DC Current Consumption

VDD = 2.0 to 3.6V, -40 to +125º C

19.2.2.1 Active Processing

19.2.2.2 Sleep Mode

19.2.2.3 Deep Sleep Mode

60 JN-DS-JN5142 1v0 © NXP Laboratories UK 2012

Page 61

19.2.3 I/O Characteristics

Parameter

Min

Typ

Max

Unit

Notes

Internal DIO pullup resistors

22 26 39 45

33 40 61 71

48, 51 59, 63 93, 97

109, 113

k

VDD2 = 3.6V VDD2 = 3.0V VDD2 = 2.2V VDD2 = 2.0V

Internal RESETN pullup resistor

158 189 287 338

231 287 450 531

335. 353 425, 448 680, 705 803, 825

k

VDD2 = 3.6V VDD2 = 3.0V VDD2 = 2.2V VDD2 = 2.0V

Digital I/O High Input (DIO0,1, 9,10, 15 - 17) (Remaining digital pins)

VDD2 x 0.7

VDD2

Lower of (VDD2 +

2V) and 5.5V

Digital I/O low Input

-0.3 VDD2 x 0.27

Digital I/O input hysteresis

140

230

310

DIO High O/P (2.7-3.6V)

VDD2 x 0.8

VDD2

With 4mA load

DIO Low O/P (2.7-3.6V)

0 0.4

With 4mA load

DIO High O/P (2.2-2.7V)

VDD2 x 0.8

VDD2

With 3mA load

DIO Low O/P (2.2-2.7V)

0 0.4

With 3mA load

DIO High O/P (2.0-2.2V)

VDD2 x 0.8

VDD2

With 2.5mA load

DIO Low O/P (2.0-2.2V)

0 0.4

With 2.5mA load

Current sink/source capability

4 3

2.5

VDD2 = 2.7V to 3.6V VDD2 = 2.2V to 2.7V VDD2 = 2.0V to 2.2V

IL -

Input Leakage Current

15, 50

Vcc = 3.6V, pin low

IH -

Input Leakage Current

15, 50

Vcc = 3.6V, pin high

Internal RESET

VDD

POT

STAB

VDD = 2.0 to 3.6V, -40 to +125º C, italic +85 ºC Bold +125 ºC

19.3 AC Characteristics

19.3.1 Reset and Supply Voltage Monitor

Figure 40: Internal Power-on Reset without Showing Brown-Out

Page 62

Internal RESET

RESETN

RST

STAB

RST

Parameter

Min

Typ

Max

Unit

Notes

External Reset pulse width to initiate reset sequence

RST

)

µs

Assumes internal pullup resistor value of 100K worst case and ~5pF external capacitance

External Reset threshold voltage (V

RST

)

VDD2 x

0.7

Minimum voltage to avoid being reset

Internal Power-on Reset threshold voltage (V

POT

)

Rise/fall time > 10mS

1.47

1.42

Rising Falling

Spike Rejection Square wave pulse 1us Triangular wave pulse 10us

1.2

1.3

Depth of pulse to trigger reset

Reset stabilisation time (t

STAB

)

45 µs

Note 1

Supply Voltage Monitor Threshold Voltage (VTH)

1.88

1.92

2.03

2.12

2.22

2.31

2.60

2.89

1.96

2.00

2.11

2.21

2.31

2.41

2.71

3.01

2.02

2.06

2.17

2.28

2.38

2.48

2.79

3.10

Configurable threshold with 8 levels

Supply Voltage Monitor Hysteresis (V

HYS

)

43 46 50 57 63 70 85

100

Corresponding to the 8 threshold levels

VDD = 2.0 to 3.6V, -40 to +125º C

Figure 41: Externally Applied Reset

Time from release of reset to start of executing ROM code. Loading program from Flash occurs in addition to this.

62 JN-DS-JN5142 1v0 © NXP Laboratories UK 2012

Page 63

VTH + VHYS

VTH

DVDD

Internal POR

Internal BOReset

VPOT

Figure 42: Power-on Reset Followed By Brown-out Detect

SSH

SSS

MOSI

(mode=1,3)

MOSI

(mode=0,2)

MISO

(mode=0,2)

MISO

(mode=1,3)

CLK

(mode=0,1)

CLK

(mode=2,3)

Parameter

Symbol

Min

Max

Unit

Clock period

tCK

62.5

Data setup time

tSI

16.7 @ 3.3V

18.2 @ 2.7V

21.0 @ 2.0V

Data hold time

tHI 0

Data invalid period

tVO - 15

Select set-up period

SSS

Select hold period

SSH

30 (SPICLK = 16MHz)

0 (SPICLK<16MHz, mode=0 or 2)

60 (SPICLK<16MHz, mode=1 or 3)

19.3.2 SPI Master Timing

Figure 43: SPI Timing (Master)

Page 64

BUF

Sr P SS

LOW

HD;STA

HD;DAT

HIGH

SU;DAT

SU;STA

HD;STA

SU;STO

SIF_D

SIF_CLK

Parameter

Symbol

Standard Mode

Fast Mode

Unit

Min

Max

Min

Max

SIF_CLK clock frequency

SCL

100 0 400

kHz

Hold time (repeated) START condition. After this period, the first clock pulse is generated

HD:STA

4 - 0.6

µs

LOW period of the SIF_CLK clock

LOW

4.7 - 1.3

µs

HIGH period of the SIF_CLK clock

HIGH

4 - 0.6

µs

Set-up time for repeated START condition

SU:STA

4.7 - 0.6

µs

Data setup time SIF_D

SU:DAT

0.25 - 0.1

µs

Rise Time SIF_D and SIF_CLK

tR - 1000

20+0.1Cb

300

Fall Time SIF_D and SIF_CLK

tF - 300

20+0.1Cb

300

Set-up time for STOP condition

SU:STO

4 -

0.6

µs

Bus free time between a STOP and START condition

BUF

4.7 - 1.3

µs

Pulse width of spikes that will be suppressed by input filters (Note 1)

tSP - 60 - 60

Capacitive load for each bus line

Cb - 400 - 400

Noise margin at the LOW level for each connected device (including hysteresis)

Vnl

0.1VDD

Noise margin at the HIGH level for each connected device (including hysteresis)

Vnh

0.2VDD

Parameter

Min

Typ

Max

Unit

Notes

Time for crystal to stabilise ready to run CPU

0.74

Reached oscillator amplitude threshold

Time for crystal to stabilise ready for radio activity

1.0

Wake up from Deep Sleep or from Sleep (memory not held)

0.05 + 0.5*

program size in

KBytes

Assumes SPI clock to external Flash is 16MHz

Wake up from Sleep (memory held)

µs

Start-up runs from High-Speed RC oscillator

Wake up from CPU Doze mode

0.2

µs

19.3.3 Two-wire Serial Interface

Figure 44: Two-wire Serial Interface Timing

Note 1: This figure indicates the pulse width that is guaranteed to be suppressed. Pulse with widths up to 125nsec may also get suppressed.

19.3.4 Wakeup and Boot Load Timings

64 JN-DS-JN5142 1v0 © NXP Laboratories UK 2012

Page 65

19.3.5 Bandgap Reference

Parameter

Min

Typ

Max

Unit

Notes

Voltage

1.156,

1.154

1.192

1.216

DC power supply rejection

58 dB

at 25ºC

Temperature coefficient

-30

+35

-60

ppm/ºC

20 to 85ºC

-40ºC to 20ºC 20 to 125 ºC

-40ºC to 85ºC

Point of inflexion

+15

ºC

Parameter

Min

Typ

Max

Unit

Notes

Resolution 8 bits

500kHz Clock

Current consumption

655 µA

Integral nonlinearity

± 1, 1.2

LSB

Differential nonlinearity

-0.5 +0.5

LSB

Guaranteed monotonic

Offset error

-10

-20

0 to Vref range 0 to 2Vref range

Gain error

+10 +20

0 to Vref range 0 to 2Vref range

Internal clock

0.25,0.5 or

1.0

MHz

16MHz input clock, 16,32or 64

No. internal clock periods to sample input

2, 4, 6 or 8

Programmable Conversion time

16 136

µs

Programmable

Input voltage range

0.04

Vref

or 2*Vref

Switchable. Refer to

17.1.1

Vref (Internal)

See Section 19.3.5

Vref (External)

1.15

1.2

1.6

Allowable range into VREF pin

Input capacitance

In series with 5K ohms

VDD = 2.0 to 3.6V, -40 to +125ºC, italic +85 ºC Bold +125 ºC

19.3.6 Analogue to Digital Converters

VDD = 3.0V, VREF = 1.2V, -40 to +125ºC, italic +85 ºC Bold +125 ºC

Page 66

Parameter

Min

Typ

Max

Unit

Notes

Analogue response time (normal)

125,130

+/- 250mV overdrive 10pF load

Total response time (normal) including delay to Interrupt controller

105

+ 125,130

Digital delay can be up to a max. of two 16MHz clock periods

Analogue response time (low power)

2.4

2.8

µs

+/- 250mV overdrive No digital delay

Hysteresis

4 12 28

10 20 40

16, 17 26, 29 50, 55

Programmable in 3 steps and zero

Vref (Internal)

See Section 19.3.5

Common Mode input range

0 Vdd

Current (normal mode)

102, 110

µA

Current (low power mode)

0.8

1.1, 1.2

µA

Parameter

Min

Typ

Max

Unit

Notes

Current consumption of cell and counter logic

680 600 500

830, 930 750, 850 650, 710

3.6V

3.0V

2.0V

32kHz clock native accuracy

-30%

32kHz

+30%

Typical is at 3.0V 25C

Calibrated 32kHz accuracy

±250

ppm

For a 1 second sleep period calibrating over 20 x 32kHz clock periods

Variation with temperature

-0.010

%/°C

Variation with VDD2

-1.8

%/V

19.3.7 Comparator

VDD = 2.0 to 3.6V -40 to +125ºC, italic +85 ºC Bold +125 ºC

19.3.8 32kHz RC Oscillator

VDD = 2.0 to 3.6V, -40 to +125 ºC, italic +85 ºC Bold +125 ºC

66 JN-DS-JN5142 1v0 © NXP Laboratories UK 2012

Page 67

19.3.9 32kHz Crystal Oscillator

Parameter

Min

Typ

Max

Unit

Notes

Current consumption of cell and counter logic

1.5

1.75, 2.0

µA

This is sensitive to the ESR of the crystal, Vdd and total capacitance at each pin

Start – up time

0.8 s

Assuming xtal with ESR of less than 40kohms and CL= 9pF External caps = 15pF

(Vdd/2mV pk-pk) see Appendix B

Input capacitance

1.4 pF

Bondpad and package

Transconductance

17 µA/V

External Capacitors (CL=9pF)

15 pF

Total external capacitance needs to be 2*CL, allowing for stray capacitance from chip, package and PCB

Amplitude at Xout

Vdd-0.2

Vp-p

Parameter

Min

Typ

Max

Unit

Notes

Current consumption

300

375

450, 500

µA

Excluding bandgap ref.

Start – up time

0.74 ms

Assuming xtal with ESR of less than 40ohms and CL= 9pF External caps = 15pF

see Appendix B

Input capacitance

1.4 pF

Bondpad and package

Transconductance

3.65, 3.55

4.30

5.16

mA/V

DC voltages, XTALIN/XTALOUT

390/425

375/405

425/465

470/520

External Capacitors (CL=9pF)

15 pF

Total external capacitance needs to be 2*CL, allowing for stray capacitance from chip, package and PCB

Amplitude detect threshold

320

mVp-p

Threshold detection accessible via API

VDD = 2.0 to 3.6V, -40 to +125ºC, italic +85 ºC Bold +125 ºC

19.3.10 32MHz Crystal Oscillator

VDD = 2.0 to 3.6V, -40 to +125ºC, italic +85 ºC Bold +125 ºC

Page 68

Parameter

Min

Typ

Max

Unit

Notes

Current consumption of cell

145

250, 275

µA

Clock native accuracy

-20%

27MHz

+26%

Calibrated centre frequency accuracy

-7%

32.1MHz

+7.5% Variation with temperature

-0.035, -0.025

-0.015, 0.010

%/°C

Variation with VDD2

-0.65

-0.35

-0.2, +0.1

%/V

Startup time

2.4

Parameter

Min

Typ

Max

Unit

Notes

Operating Range

-40 - 125

C

Sensor Gain

-1.44

-1.55

-1.66

mV/C

Accuracy - -

10

C

Non-linearity

2.5, 3.5

C

Output Voltage

630, 570

855

Includes absolute variation due to manufacturing & temp

Typical Voltage

745 mV

Typical at 3.0V 25C

Resolution

0.154

0.182

0.209

C/LSB

0 to Vref ADC I/P Range

19.3.11 High-Speed RC Oscillator

VDD = 2.0 to 3.6V, -40 to +125ºC, italic +85 ºC Bold +125 ºC

19.3.12 Temperature Sensor

VDD = 2.0 to 3.6V, -40 to +125ºC, italic +85 ºC Bold +125 ºC

Page 69

19.3.13 Radio Transceiver

Parameter

Min

Typical

Max

Notes

RF Port Characteristics

Type

Single Ended

Impedance

50ohm

2.4-2.5GHz

Frequency range

2.400 GHz

2.485GHz

ESD levels (pin 17)

2KV (HBM)

500v (CDM)

This JN5142 meets all the requirements of the IEEE802.15.4 standard over 2.0 - 3.6V and offers the following improved RF characteristics. All RF characteristics are measured single ended.

This part also meets the following regulatory body approvals, when used with NXP‟s Module Reference Designs. Compliant with FCC part 15, rules, IC Canada, ETSI ETS 300-328 and Japan ARIB STD-T66

 The PCB schematic and layout rules detailed in Appendix B.4

1) With external matching inductors and assuming PCB layout as in Appendix B.4.

Page 70

Parameter

Min

Typical

Max

Unit

Notes

Receiver Characteristics

Receive sensitivity

-92

-95 dBm

Nominal for 1% PER, as per

802.15.4 Section 6.5.3.3

Maximum input signal

+10

dBm

For 1% PER, measured as sensitivity

Adjacent channel rejection (-1/+1 ch)

[CW Interferer]

19/34

[27/49]

dBc

For 1% PER, with wanted signal 3dB, above sensitivity. (Note1,2) (modulated interferer)

Alternate channel rejection (-2/+2 ch)

[CW Interferer]

40/45

[54/54]

dBc

For 1% PER, with wanted signal 3dB, above sensitivity. (Note1,2) (modulated interferer)

Other in band rejection

2.4 to 2.4835 GHz, excluding adj channels

48 dBc

For 1% PER with wanted signal 3dB above sensitivity. (Note1)

Out of band rejection

52 dBc

For 1% PER with wanted signal 3dB above sensitivity. All frequencies except wanted/2 which is 8dB lower. (Note1)

Spurious emissions (RX)

-61

<-70

-58

dBm

Measured conducted into 50ohms 30MHz to 1GHz

1GHz to 12GHz

Intermodulation protection

40 dB

For 1% PER at with wanted signal 3dB above sensitivity. Modulated Interferers at 2 & 4 channel separation (Note1)

RSSI linearity

-4 +4

-95 to -10dBm. Available through Hardware API

Transmitter Characteristics

Transmit power

+0.5

+2.5

dBm

Output power control range

-35 dB

In three 12dB steps (Note3)

Spurious emissions (TX)

-40

<-70

dBm

Measured conducted into 50ohms 30MHz to 1GHz, 1GHz to12.5GHz,

The following exceptions apply

1.8 to 1.9GHz & 5.15 to 5.3GHz

EVM [Offset]

10 [2.0]

At maximum output power

Transmit Power Spectral Density

-38

-20

dBc

At greater than 3.5MHz offset, as per 802.15.4, Section 6.5.3.1

Radio Parameters: 2.0-3.6V, +25ºC

Page 71

Radio Parameters: 2.0-3.6V, -40ºC

Parameter

Min

Typical

Max

Unit

Notes

Receiver Characteristics

Receive sensitivity

-93.5

-96.5

dBm

Nominal for 1% PER, as per

802.15.4 Section 6.5.3.3

Maximum input signal

+10

dBm

For 1% PER, measured as sensitivity

Adjacent channel rejection (-1/+1 ch)

[CW Interferer]

19/34

[TBC]

dBc

For 1% PER, with wanted signal 3dB, above sensitivity. (Note1,2) (modulated interferer)

Alternate channel rejection (-2/+2 ch)

[CW Interferer]

40/45

[TBC]

dBc

For 1% PER, with wanted signal 3dB, above sensitivity. (Note1,2) (modulated interferer)

Other in band rejection

2.4 to 2.4835 GHz, excluding adj channels

47 dBc

For 1% PER with wanted signal 3dB above sensitivity. (Note1)

Out of band rejection

49 dBc

For 1% PER with wanted signal 3dB above sensitivity. All frequencies except wanted/2 which is 8dB lower. (Note1)

Spurious emissions (RX)

-60

<-70

-57

dBm

Measured conducted into 50ohms 30MHz to 1GHz

1GHz to 12GHz

Intermodulation protection

39 dB

For 1% PER at with wanted signal 3dB above sensitivity. Modulated Interferers at 2 & 4 channel separation (Note1)

RSSI linearity

-4 +4

-95 to -10dBm. Available through Hardware API

Transmitter Characteristics

Transmit power

+0.75

+2.75

dBm

Output power control range

-35 dB

In three 12dB steps (Note3)

Spurious emissions (TX)

-40

<-70

dBm

Measured conducted into 50ohms 30MHz to 1GHz, 1GHz to12.5GHz,

The following exceptions apply

1.8 to 1.9GHz & 5.15 to 5.3GHz

EVM [Offset]

9 [2.0]

At maximum output power

Transmit Power Spectral Density

-38

-20

dBc

At greater than 3.5MHz offset, as per 802.15.4, Section 6.5.3.1

Page 72

Parameter

Min

Typical

Max

Unit

Notes

Receiver Characteristics

Receive sensitivity

-90

-93 dBm

Nominal for 1% PER, as per

802.15.4 Section 6.5.3.3

Maximum input signal

+5 dBm

For 1% PER, measured as sensitivity

Adjacent channel rejection (-1/+1 ch)

[CW Interferer]

19/34

[TBC]

dBc

For 1% PER, with wanted signal 3dB, above sensitivity. (Note1,2) (modulated interferer)

Alternate channel rejection (-2/+2 ch)

[CW Interferer]

40/45

[TBC]

dBc

For 1% PER, with wanted signal 3dB, above sensitivity. (Note1,2) (modulated interferer)

Other in band rejection

2.4 to 2.4835 GHz, excluding adj channels

49 dBc

For 1% PER with wanted signal 3dB above sensitivity. (Note1)

Out of band rejection

53 dBc

For 1% PER with wanted signal 3dB above sensitivity. All frequencies except wanted/2 which is 8dB lower. (Note1)

Spurious emissions (RX)

-62

<-70

-59

dBm

Measured conducted into 50ohms 30MHz to 1GHz

1GHz to 12GHz

Intermodulation protection

41 dB

For 1% PER at with wanted signal 3dB above sensitivity. Modulated Interferers at 2 & 4 channel separation (Note1)

RSSI linearity

-4 +4

-95 to -10dBm. Available through Hardware API

Transmitter Characteristics

Transmit power

-0.2

+1.8

dBm

Output power control range

-35 dB

In three 12dB steps (Note3)

Spurious emissions (TX)

-38

<-70

dBm

Measured conducted into 50ohms 30MHz to 1GHz, 1GHz to12.5GHz,

The following exceptions apply

1.8 to 1.9GHz & 5.15 to 5.3GHz

EVM [Offset]

10 [2.0]

At maximum output power

Transmit Power Spectral Density

-38

-20

dBc

At greater than 3.5MHz offset, as per 802.15.4, Section 6.5.3.1

Radio Parameters: 2.0-3.6V, +85ºC

Page 73

Radio Parameters: 2.0-3.6V, +125ºC

Parameter

Min

Typical

Max

Unit

Notes

Receiver Characteristics

Receive sensitivity

-88

-91 dBm

Nominal for 1% PER, as per

802.15.4 Section 6.5.3.3

Maximum input signal

dBm

For 1% PER, measured as sensitivity

Adjacent channel rejection (-1/+1 ch)

[CW Interferer]

20/34

[TBC]

dBc

For 1% PER, with wanted signal 3dB, above sensitivity. (Note1,2) (modulated interferer)

Alternate channel rejection (-2/+2 ch)

[CW Interferer]

40/45

[TBC]

dBc

For 1% PER, with wanted signal 3dB, above sensitivity. (Note1,2) (modulated interferer)

Other in band rejection

2.4 to 2.4835 GHz, excluding adj channels

49 dBc

For 1% PER with wanted signal 3dB above sensitivity. (Note1)

Out of band rejection

53 dBc

For 1% PER with wanted signal 3dB above sensitivity. All frequencies except wanted/2 which is 8dB lower. (Note1)

Spurious emissions (RX)

-64

<-70

-61

dBm

Measured conducted into 50ohms 30MHz to 1GHz

1GHz to 12GHz

Intermodulation protection

41 dB

For 1% PER at with wanted signal 3dB above sensitivity. Modulated Interferers at 2 & 4 channel separation (Note1)

RSSI linearity

-4 +4

-95 to -10dBm. Available through Hardware API

Transmitter Characteristics

Transmit power

-0.8

+1.2

dBm

Output power control range

-35 dB

In three 12dB steps (Note3)

Spurious emissions (TX)

-37

<-70

dBm

Measured conducted into 50ohms 30MHz to 1GHz, 1GHz to12.5GHz,

The following exceptions apply

1.8 to 1.9GHz & 5.15 to 5.3GHz

EVM [Offset]

10 [3.0]

At maximum output power

Transmit Power Spectral Density

-38

-20

dBc

At greater than 3.5MHz offset, as per 802.15.4, Section 6.5.3.1

Page 74

Note1: Blocker rejection is defined as the value, when 1% PER is seen with the wanted signal 3dB above sensitivity, as per 802.15.4 Section 6.5.3.4

Note2: Channels 11,17,24 low/high values reversed. Note3: Up to an extra 2.5dB of attenuation is available if required.

Page 75

Appendix A Mechanical and Ordering Information

UNIT

max.

A1 b c D Dh E Eh e e1

e2 L v w y

0.05

0.00

0.30

0.18

0.2

6.1

5.9

4.75

4.45

6.1

5.9

4.75

4.45

0.5

4.5

0.5

0.3

0.1

0.05

0.1

A.1 SOT618-1 HVQFN40 40-pin QFN Package Drawing

Figure 45: 40-pin QFN Package Drawings

Table 11: Package Dimensions

 Plastic or metal protrusions of 0.075 mm maximum per side are

not included.

Page 76

By C D

SLx

Sly

SPx tot

Spy tot

SPx

Spy

0.500

7.000

5.200

0.900

0.290

4.100

2.400

0.600

6.300

7.250

Table 12: Footprint Dimensions

A.2 Footprint information

Information for reflow soldering. All dimensions are given in the table underneath.

Figure 46: PCB Decal

Page 77

 The PCB schematic and layout rules detailed in Appendix B.4 must

be followed. Failure to do so will likely result in the JN5142 failing to meet the performance specification detailed herein and worst case may result in device not functioning in the end application.

Page 78

Part Number

Ordering Code

Description

JN5142-001

JN5142N/001

JN5142 microcontroller with 001 ROM

JN5142-J01

JN5142N/J01

JN5142 microcontroller with J01 ROM

A.3 Ordering Information

The standard qualification for the JN5142 is extended industrial temperature range: -40ºC to +125ºC, packaged in a 40-pin QFN package.

Ordering code format:

JN5142N / XXX

XXX: ROM Variant:

001 IEEE802.15.4, RF4CE and Active RFID J01 JenNet-IP

The device is available in two different reel quantities

 Tape mounted 4000 devices on a 330mm reel  Tape mounted 1000 devices on a 180mm reel

Order Codes:

The Standard Supply Multiple (SSM) for Engineering Samples or Prototypes is 50 units with a maximum of 250 units. If the quantity of Engineering Samples or Prototypes ordered is less than a reel quantity, then these will be shipped in tape form only, with no reel and will not be dry packaged in a moisture sensitive environment.

The SSM for Production status devices is one reel, all reels are dry packaged in a moisture barrier bag see A.5.3.

Page 79

A.4 Device Package Marking

J N 5 1 4 2 S

X X X X X X X X X X F F

X X X Y W W XX

J N 5 1 4 2 B

R U L 2 8 0 0 0 Y U 0 1

q S D 1 2 5 -X

Network Stack

Ordering Code

Part Marking

IEEE802.15.4 & RF4CE

JN5142N/001

JN5142B

JenNet-IP

JN5142N/J01

JN5142C

The diagram below shows the package markings for JN5142. The package on the left along with the legend information below it, shows the general format of package marking. The package on the right shows the specific markings for a JN5142 device, with revision B ROM software, that came from assembly build number 01 and was manufactured week 25 of 2011.

Figure 47: Device Package Marking

Legend:

JN Family part code XXXX 4 digit part number S Software ROM identifier letter FF 2 digit assembly build number Y 1 digit year number WW 2 digit week number

Page 80

Reference

Dimensions (mm)

6.30 0.10

1.10 0.10

7.500 0.10

12.0 0.10

16.00 +0.30/-0.3

A.5 Tape and Reel Information

A.5.1 Tape Orientation and Dimensions

The general orientation of the 40QFN package in the tape is as shown in Figure 48.

Figure 48: Tape and Reel Orientation

Figure 49 shows the detailed dimensions of the tape used for 6x6mm 40QFN devices.

(I) Measured from centreline of sprocket hole to centreline of pocket (II) Cumulative tolerance of 10 sprocket holes is 0.20mm (III) Measured from centreline of sprocket hole to centreline of pocket (IV) Other material available

Figure 49: Tape Dimensions

Page 81

A.5.2 Reel Information: 180mm Reel

Surface Resistivity

Between 1x1010 – 1x1012 Ohms Square

Material

High Impact Polystyrene, environmentally friendly, recyclable

All dimensions and tolerances are fully compliant with EIA-481-B and are specified in millimetres. 6 window design with one window on each side blanked to allow adequate labelling space.

Figure 50: Reel Dimensions

Page 82

Surface Resistivity

Between 10e9 – 10e11 Ohms Square

Material

High Impact Polystyrene with Antistatic Additive

A.5.3 Reel Information: 330mm Reel

All dimensions and tolerances are fully compliant with EIA-481-B and are specified in millimetres. 3 window design to allow adequate labelling space.

A.5.4 Dry Pack Requirement for Moisture Sensitive Material

Moisture sensitive material, as classified by JEDEC standard J-STD-033, must be dry packed. The 56 lead QFN package is MSL2A/260C, and is dried before sealing in a moisture barrier bag (MBB) with desiccant bag weighing at

67.5 grams of activated clay and a humidity indicator card (HIC) meeting MIL-L-8835 specification. The MBB has a moisture-sensitivity caution label to indicate the moisture-sensitive classification of the enclosed devices.

Figure 51: 330mm Reel Dimensions

Page 83

Appendix B Development Support

C2C1

2121TT

CCCC



inPT CCCC 1111 

PC1

inC1

2TC

B.1 Crystal Oscillators

This Section covers some of the general background to crystal oscillators, to help the user make informed decisions concerning the choice of crystal and the associated capacitors.

B.1.1 Crystal Equivalent Circuit

Where

is the motional capacitance

is the motional inductance. This together with mCdefines the oscillation frequency (series)

is the equivalent series resistance ( ESR ).

is the shunt or package capacitance and this is a parasitic

B.1.2 Crystal Load Capacitance

The crystal load capacitance is the total capacitance seen at the crystal pins, from all sources. As the load

capacitance (CL) affects the oscillation frequency by a process known as „pulling‟, crystal manufacturers specify the

frequency for a given load capacitance only. A typical pulling coefficient is 15ppm/pF, to put this into context the maximum frequency error in the IEEE802.15.4 specification is +/-40ppm for the transmitted signal. Therefore, it is important for resonance at 32MHz exactly, that the specified load capacitance is provided.

The load capacitance can be calculated using:

Total capacitance

Where 1C is the capacitor component

Similarly for Hence for a 9pF load capacitance, and a tight layout the external capacitors should be 15pF

is the PCB parasitic capacitance. With the recommended layout this is about 1.6pF

is the on-chip parasitic capacitance and is about 1.4pF typically.

Page 84



 





 













NEG



 TTmCC





 





 





2121

])([4

TTTTSm

CCCCCR









1TC=2TC

B.1.3 Crystal ESR and Required Transconductance

The resistor in the crystal equivalent circuit represents the energy lost. To maintain oscillation, power must be supplied by the amplifier, but how much? Firstly, the Pi connected capacitors C1 and C2 with CS from the crystal, apply an impedance transformation to Rm, when viewed from the amplifier. This new value is given by:

The amplifier is a transconductance amplifier, which takes a voltage and produces an output current. The amplifier together with the capacitors C1 and C2, form a circuit, which provides a negative resistance, when viewed from the crystal. The value of which is given by:

Where

Derivations of these formulas can be easily found in textbooks. In order to give quick and reliable oscillator start-up, a common rule of thumb is to set the amplifier negative

resistance to be a minimum of 4 times the effective crystal resistance. This gives

This can be used to give an equation for the required transconductance.

is the transconductance

is the frequency in rad/s

Example: Using typical 32MHz crystal parameters of mR=40, SC=1pF and capacitance of 9pF), the equation above gives the required transconductance (mg) as 2.59mA/V. The JN5142 has a

typical value for transconductance of 4.3mA/V The example and equation illustrate the trade-off that exists between the load capacitance and crystal ESR. For

example, a crystal with a higher load capacitance can be used, but the value of max. ESR that can be tolerated is reduced. Also note, that the circuit sensitivity to external capacitance [ C1 , C2 ] is a square law.

Meeting the criteria for start-up is only one aspect of the way these parameters affect performance, they also affect the time taken during start-up to reach a given, (or full), amplitude. Unfortunately, there is no simple mathematical model for this, but the trend is the same. Therefore, both a larger load capacitance and larger crystal ESR will give a longer start-up time, which has the disadvantages of reduced battery life and increased latency.

=18pF ( for a load

Page 85

B.2 32MHz Oscillator

XTALOUT

XTALIN

JN5142

Parameter

Min

Typ

Max

Notes

Crystal Frequency

32MHz

Crystal Tolerance

40ppm

Including temperature and ageing

Crystal ESR Range (Rm)

10 60

See below for more details

Crystal Load Capacitance Range (CL)

6pF

9pF

12pF

See below for more details

Not all Combinations of Crystal Load Capacitance and ESR are Valid

Recommended Crystal

Load Capacitance 9pF and max ESR 40 

External Capacitors (C1 & C2) For recommended Crystal

15pF

CL = 9pF, total external capacitance needs to be 2*CL. , allowing for stray capacitance from chip, package and PCB

The JN5142 contains the necessary on-chip components to build a 32 MHz reference oscillator with the addition of an external crystal resonator, two tuning capacitors. The schematic of these components are shown in Figure 52. The two capacitors, C1 and C2, will typically be 15pF ±5% and use a COG dielectric. For a detailed specification of the crystal required and factors affecting C1 and C2 see Appendix B.1. As with all crystal oscillators the PCB layout is especially important, both to keep parasitic capacitors to a minimum and to reduce the possibility of PCB noise being coupled into the oscillator.

Figure 52: Crystal Oscillator Connections

The clock generated by this oscillator provides the reference for most of the JN5142 subsystems, including the transceiver, processor, memory and digital and analogue peripherals.

32MHz Crystal Requirements

Page 86

4.1

4.15

4.2

4.25

4.3

4.35

-40 -20 0 20 40 60 80 100

Transconductance (mA/V)

Temperature (C)

32MHz Crystal Oscillator

4.28

4.29

4.3

4.31

2 2.2 2.4 2.6 2.8 3 3.2 3.4 3.6

Transconductance (mA/V)

Supply Voltage (VDD)

32MHz Crystal Oscillator

As is stated above, not all combinations of crystal load capacitance and ESR are valid, and as explained in Appendix B.1.3 there is a trade-off that exists between the load capacitance and crystal ESR to achieve reliable performance.

For this reason, we recommend that for a 9pF load capacitance crystals be specified with a maximum ESR of 40 ohms. For lower load capacitances the recommended maximum ESR rises, for example, CL=7pF the max ESR is 61 ohms. For the lower cost crystals in the large HC49 package, a load capacitance of 9 or 10pF is widely available and the max ESR of 30 ohms specified by many manufacturers is acceptable. Also available in this package style, are crystals with a load capacitance of 12pF, but in this case the max ESR required is 25 ohms or better.

Below is measurement data showing the variation of the crystal oscillator amplifier transconductance with temperature and supply voltage, notice how small the variation is. Circuit techniques have been used to apply compensation, such that the user need only design for nominal conditions.

Page 87

32KXTALOUT32KXTALIN

JN5142

Parameter

Min

Typ

Max

Notes

Crystal Frequency

32kHz

Supply Current

1.6µA

Vdd=3v, temp=25 C, load cap =9pF, Rm=25K

Supply Current Temp. Coeff.

0.1%/C

Vdd=3v

Crystal ESR Range (Rm)

10K

25K

80K

See below for more details

Crystal Load Capacitance Range (CL)

6pF

9pF

12.5pF

See below for more details

Not all Combinations of Crystal Load Capacitance and ESR are Valid

B.3 32kHz Oscillator

In order to obtain more accurate sleep periods, the JN5142 contains the necessary on-chip components to build an optional 32kHz oscillator with the addition of an external 32.768kHz crystal and two tuning capacitors. The crystal should be connected between XTAL32K_IN and XTAL32K_OUT (DIO9 and DIO10), with two equal capacitors to ground, one on each pin. The schematic of these components are shown in Figure 53. The two capacitors, C1 and C2, will typically be in the range 10 to 22pF ±5% and use a COG dielectric. As with all crystal oscillators the PCB layout is especially important, both to keep parasitic capacitors to a minimum and to reduce the possibility of PCB noise being coupled into the oscillator.

Figure 53: 32kHz Crystal Oscillator Connections

The electrical specification of the oscillator can be found in 19.3.9. The oscillator cell is flexible and can operate with a range of commonly available 32kHz crystals with load capacitances from 6 to 12.5p, and ESR up to 80K. It achieves this by using automatic gain control (AGC), which senses the signal swing. As explained in Appendix B.1.3 there is a trade-off that exists between the load capacitance and crystal ESR to achieve reliable performance. The use of an AGC function allows a wider range of crystal load capacitors and ESR‟s to be accommodated than would otherwise be possible. However, this benefit does mean the supply current varies with the supply voltage (VDD), value of the total capacitance at each pin, and the crystal ESR. This is described in the table and graphs below.

32kHz Crystal Requirements

Page 88

Load Capacitance

Ext Capacitors

Current

Start-up Time

Max ESR

9pF

15pF

1.6µA

0.8Sec

70K

6pF

9pF

1.4µA

0.6sec

80K

12.5pF

22pF

2.4µA

1.1sec

35K

0.6

0.8

1.2

1.4

1.6

2.2 2.4 2.6 2.8 3 3.2 3.4 3.6

Normalised Current (IDD)

Supply Voltage (VDD)

32KHz Crystal Oscillator Current

0.6

0.8

1.2

1.4

1.6

10 20 30 40 50 60 70 80

Normalised Current (IDD)

Crystal ESR (K ohm)

32KHz Crystal Oscillator Current

9pF

12.5pF

Three examples of typical crystals are given, each with the value of external capacitors to use, plus the likely supply current and start-up time that can be expected. Also given is the maximum recommended ESR based on the start-up criteria given in Appendix B.1.3. The values of the external capacitors can be calculated using the equation in Appendix B.1.2 .

Below is measurement data showing the variation of the crystal oscillator supply current with voltage and with crystal ESR, for two load capacitances.

Page 89

B.4 JN5142 Module Reference Designs

40 39 38 37 36 35 34 33 32 31

VSSA

1918

1716

1514

131211

COMP1P

COMP1M

RESETN

XTAL_OUT

XTAL_IN

VB_SYNTH

VCOTUNE (NC)

VB_VCO

VDD1

IBIAS

VREF

VB_RF2

RF_IN

VB_RF

ADC1

SPISEL1

SPISEL2

DIO2

DIO3

SPICLK

VSS1

SPIMISO

SPIMOSI

SPISELO

VB_RAM

CTS0

RTS0

TXD0

RXD0

VDD2

SIF_D

VSS2

SIF_CLK

DIO13

DIO12

VB_DIG

DIO11

TIM0OUT

TIM0CAP TIM0CK_GT

C7: 100nF

2-wire Serial Port Timer0

C16: 100nF

UART0/JTAG

C6: 100nF

Serial

Flash

Memory

VDD

SDO

VSS

SS VCC

HOLD

CLK

SDI

SPI Select

Analogue IO

C12: 47pF C3: 100nFC1: 47pF

L1: 5.6nH

L2: 2.7nH

VB_RF

R1: 43k

To coaxial socket

or integrated antenna

C20: 100nF

C14: 100nFC13: 10µF

VDD

C2: 10nF

C15: 100nF

C10: 15pF

C11: 15pF

Analogue IO

VDD

VB_RF1

For customers wishing to integrate the JN5142 device directly into their system, NXP provide a range of Module Reference Designs, covering standard and high-power modules fitted with different Antennae

To ensure the correct performance, it is strongly recommended that where possible the design details provided by the reference designs, are used in their exact form for all end designs, this includes component values, pad dimensions, track layouts etc. In order to minimise all risks, it is recommended that the entire layout of the appropriate reference module, if possible, be replicated in the end design.

For full details, see [6]. Please contact technical support via the on-line tech-support system.

(www.jennic.com/support)

B.4.1 Schematic Diagram

A schematic diagram of the JN5142 PCB antenna reference module is shown in

Figure 54. Details of component values and PCB layout constraints can be found in Table 13.

Page 90

40 39 38 37 36 35 34 33 32 31

VSSA

1918

1716

1514

131211

COMP1P

COMP1M

RESETN

XTAL_OUT

XTAL_IN

VB_SYNTH

VCOTUNE (NC)

VB_VCO

VDD1

IBIAS

VREF

VB_RF2

RF_IN

VB_RF

ADC1

SPISEL1

SPISEL2

DIO2

DIO3

SPICLK

VSS1

SPIMISO

SPIMOSI

SPISELO

VB_RAM

CTS0

RTS0

TXD0

RXD0

VDD2

SIF_D

VSS2

SIF_CLK

DIO13

DIO12

VB_DIG

DIO11

TIM0OUT

TIM0CAP TIM0CK_GT

C7: 100nF

2-wire Serial Port Timer0

C16: 100nF

UART0/JTAG

C6: 100nF

Serial

Flash

Memory

VDD

SDO

VSS

SS VCC

HOLD

CLK

SDI

SPI Select

Analogue IO

C12: 47pF C3: 100nFC1: 47pF

L1: 5.6nH

L2: 2.7nH

VB_RF

R1: 43k

To coaxial socket

or integrated antenna

C20: 100nF

C14: 100nFC13: 10µF

VDD

C2: 10nF

C15: 100nF

C10: 15pF

C11: 15pF

Analogue IO

VDD

VB_RF1

Figure 54: JN5142 Printed Antenna Reference Module Schematic Diagram

Page 91

Component

Designator

Value/Type

Function

PCB Layout Constraints

C13

10µF

Power source decoupling

C14

100nF

Analogue Power decoupling

Adjacent to U1 pin 9

C16

100nF

Digital power decoupling

Adjacent to U1 pin 30

C15

100nF

VB Synth decoupling

Less than 5mm from U1 pin 6

10nF

VB VCO decoupling

Less than 5mm from U1 pin 8

100nF

VB RF decoupling

Less than 5mm from U1 pin 12 and U1 pin 14

C12

47pF

VB RF decoupling

Less than 5mm from U1 pin 12 and U1 pin 14

100nF

VB RAM decoupling

Less than 5mm from U1 pin 25

100nF

VB Dig decoupling

Less than 5mm from U1 pin 35

43k

I Bias Resistor

Less than 5mm from U1 pin 10

C20

100nF

Vref decoupling (optional)

Less than 5mm from U1 pin 11

1Mbit

Serial Flash Memory (Micron M25P10)

32MHz

Crystal (AEL X32M000000S039 or Epson Toyocom X1E000021016700) (CL = 9pF, Max ESR 40R)

C10

15pF +/-5% COG

Crystal Load Capacitor

Adjacent to pin 4 and Y1 pin 1

C11

15pF +/-5% COG

Crystal Load Capacitor

Adjacent to pin 5 and Y1 pin 3

47pF

AC Coupling Phycomp 2238-869-15479

Must be copied directly from the reference design.

5.6nH

RF Matching Inductor MuRata LQP15MN5N6B02

2.7nH

Load Inductor MuRata LQP15MN2N7B02

Table 13: JN5142 Printed Antenna Reference Module Components and PCB Layout Constraints

The paddle should be connected directly to ground. Any pads that require connection to ground should do so by connecting directly to the paddle.

Page 92

B.4.2 PCB Design and Reflow Profile

PCB and land pattern designs are key to the reliability of any electronic circuit design. The Institute for Interconnecting and Packaging Electronic Circuits (IPC) defines a number of standards for electronic

devices. One of these is the "Surface Mount Design and Land Pattern Standard" IPC-SM-782 [3], commonly referred to as “IPC782". This specification defines the physical packaging characteristics and land patterns for a range of surface mounted devices. IPC782 is also a useful reference document for general surface mount design techniques, containing sections on design requirements, reliability and testability. NXP strongly recommends that this be referred to when designing the PCB.

NXP also provide application note AN10366, “HVQFN application information” [7] which describes the reflow soldering process. The suggested reflow profile, from that application note, is shown in Figure 55. The specific paste manufacturers guidelines on peak flow temperature, soak times, time above liquidus and ramp rates should also be referenced.

Figure 55: Recommended Reflow Profile for Lead-free Solder Paste (SNAgCu) or PPF Lead Frame

B.4.3 Moisture Sensitivity Level (MSL)

If there is moisture trapped inside a package, and the package is exposed to a reflow temperature profile, the moisture may turn into steam, which expands rapidly. This may cause damage to the inside of the package

(delamination), and it may result in a cracked semiconductor package body (the popcorn effect). A package‟s MSL

depends on the package characteristics and on the temperature it is exposed to during reflow soldering. This is explained in more detail in [8].

Depending on the damage after this test, an MSL of 1 (not sensitive to moisture) to 6 (very sensitive to moisture) is attached to the semiconductor package.

Page 93