Rainbow Electronics MAXQ7667 User Manual

General Description

The MAXQ7667 smart system-on-a-chip (SoC) provides a time-of-flight ultrasonic distance-measuring solution. The device is optimized for applications involving large distance measurement with weak input signals or multiple target identification. The MAXQ7667 features high signalto-noise ratio achieved by combining flexible electronics with the intelligence necessary to optimize each function as environmental and target conditions change.

An integrated burst signal generator and echo reception components process ultrasonic signals between 25kHz and 100kHz. Echo reception components include a programmable gain low-noise amplifier (LNA), a 16-bit sigma-delta ADC to digitize the received echo signals, and digital signal processing (DSP). DSP limits noise with a bandpass filter, and creates an echo envelope through demodulation and lowpass filtering. Input referred noise is a low 0.7µV

RMS

. A programmable phase-locked loop (PLL) frequency synthesizer supplies the reference frequency for the burst generator and the clock for the echo receiver’s digital filter. An embedded 16-bit MAXQ20 microcontroller (µC) controls all the preceding functions.

The µC optimizes the burst frequency and reception frequency for each transmission at any temperature. The MAXQ7667 achieves smart sensing by monitoring the echo signals and then actively changing the transmitted and received parameters to obtain optimum results. Digital filtering and burst synthesis do not require CPU intervention. This leaves all the CPU power available for echo optimization, communication, diagnostics, and additional signal processing.

The MAXQ7667 operates with three different power supply voltages: +5V, +3.3V, and +2.5V. Two internal linear regulators allow operation from a single +5V supply when three external power supplies are not available. Alternatively, the MAXQ7667 can control an external pass transistor to allow operation from a single supply voltage of +8V to +65V or more, depending on the external component tolerance. The device is available in a 48-pin LQFP package and is specified to operate from -40°C to +125°C.

Applications

Features

o Smart Analog Peripherals

Dedicated Ultrasonic Burst Generator Echo Receiving Path (Includes LNA, Sigma-

Delta ADC) 5-Channel, 12-Bit SAR ADC with 250ksps

Sampling Rate Internal Bandgap Voltage Reference for the

ADCs (Also Accepts External Voltage Reference)

o Timer/Digital I/O Peripherals o High-Performance, Low-Power, 16-Bit RISC Core o Program and Data Memory o Crystal/Clock Module o 16 x 16 Hardware Multiplier with 48-Bit

Accumulator, Single Clock Cycle

o Power-Management Module o JTAG Interface o Universal Asynchronous Receiver-Transmitter

(UART)

o Local Interconnect Network (LIN)

MAXQ7667

16-Bit, RISC, Microcontroller-Based,

Ultrasonic Distance-Measuring System

________________________________________________________________

Maxim Integrated Products

Ordering Information

19-4598; Rev 1; 7/09

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Note: Some revisions of this device may incorporate deviations from published specifications known as errata. Multiple revisions of any device

may be simultaneously available through various sales channels. For information about device errata, go to: ww.maxim-ic.com/errata

Pin Configuration appears at end of data sheet.

See the

Detailed Features

section for complete list of features.

Note: All devices are specified over the -40°C to +125°C operating temperature range.

/V denotes an automotive qualified part.

Denotes a lead(Pb)-free/RoHS-compliant package.

PART PIN-PACKAGE

RAM

(KB)

FLASH

(KB)

MAXQ7667AACM/V+

48 LQFP 4 32

Automotive Parking

Vehicle Security

Industrial Processing

Automation

Handheld Devices

MAXQ7667

16-Bit, RISC, Microcontroller-Based, Ultrasonic Distance-Measuring System

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

DVDDIO

= +5V, V

AVDD

= +3.3V; V

DVDD

= +2.5V, system clock (f

SYSCLK

) = 16MHz, burst frequency (f

BURST

) = bandpass frequency

BPF

) = 50kHz, C

REFBG

= C

REF

= 1µF in parallel with 0.01µF, f

ADCCLK

= 2MHz (SAR data rate = 125ksps), TA= T

MIN

to T

MAX

, unless

otherwise specified. Typical values are at T

= +25°C.)

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

DVDDIO, GATE5, REG3P3, REG2P5 to

DGND ................................................................-0.3V to +6.0V

AVDD to AGND .....................................................-0.3V to +4.0V

DVDD to DGND .....................................................-0.3V to +3.0V

DVDDIO to DVDD..................................................-0.3V to +6.0V

AVDD to DVDD......................................................-0.3V to +4.0V

AGND to DGND.....................................................-0.3V to +0.3V

Digital Inputs/Outputs to DGND..........-0.3V to (V

DVDDIO

+ 0.3V)

Analog Inputs/Outputs to AGND ............-0.3V to (V

AVDD

+ 0.3V)

XIN, XOUT to DGND ..............................-0.3V to (V

DVDD

+ 0.3V)

Maximum Current into Any Pin............................................50mA

Continuous Power Dissipation (T

= +70°C)

48-Pin LQFP (derate 21.7mW/°C above +70°C).....1739.1mW

Operating Temperature Range .........................-40°C to +125°C

Storage Temperature Range .............................-60°C to +150°C

Lead Temperature (soldering, 10s) .................................+300°C

ECHO INPUT (Low-Noise Amplifier and Sigma-Delta ADC)

Input-Referred Noise (Note 1)

Minimum Detectable Signal

Operating Input Range

Programmable Gain

Programmable-Gain Adjust Resolution

LNA Bandwidth 150 kHz

ADC Sampling Rate 80 x f

ADC Output Data Rate 10 x f

ADC Output Data Re solution 16 B its

Echo-Input Resistance RIN For each echo input 14 k

Echo-Input Capacitance 14 pF

Echo-Input DC Bias Voltage V

Maximum Overvoltage Recovery Time

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

(Note 2) 10 %

Recover from 2V

VGA gain adjust = 1.55µV

VGA gain adjust = 0.1µV

VGA gain adjust = 1.55µV

VGA gain adjust = 0.1µV

VGA gain adjust = 1.55µV unclipped

VGA gain adjust = 0.1µV unclipped

From echo input to bandpass filter in reply to input

P-P

/LSB 5.6

P-P

/LSB 0.7

P-P

/LSB 80

P-P

/LSB 10

P-P

/LSB,

P-P

/LSB,

P-P

VGA gain adjust

P-P

/LSB

= 1.55µV

VGA gain adjust = 0.1µV

input 10 µs

100

6.7

1.55

0.1

AVDD

kHz

BPF

kHz

BPF

/2 V

µV

RMS

µV

P-P

/LSB

P-P

MAXQ7667

16-Bit, RISC, Microcontroller-Based,

Ultrasonic Distance-Measuring System

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

DVDDIO

= +5V, V

AVDD

= +3.3V; V

DVDD

= +2.5V, system clock (f

SYSCLK

) = 16MHz, burst frequency (f

BURST

) = bandpass frequency

BPF

) = 50kHz, C

REFBG

= C

REF

= 1µF in parallel with 0.01µF, f

ADCCLK

= 2MHz (SAR data rate = 125ksps), TA= T

MIN

to T

MAX

, unless

otherwise specified. Typical values are at T

= +25°C.)

BANDPASS FILTER

Center Frequency f

Passband Width -3dB 0.14 x f

Minimum Stopband Rejection

Output Data Rate 10 x f

Output Data Resolution 16 Bits

LOW PA S S FILTE R

Cor ner Frequency f

Rolloff 40 dB/Decade

Output Data Rate 5 x f

Output Data Resolution 16 Bits

SAR ADC

Resolution

Integral Nonlinearity Tested at 125ksps ±1 ±2 LSB

Differential Nonlinearity Te sted at 125ksps -2 +2 LSB

Offset Error ±1 ±3 mV

Offset-Error Drift ±5 µV/°C

Gain Error ±1 %

Gain-Error Temperature Coefficient

Input-Referred Noise At ADC input s 400 µV

Differential Input Range

Abso lute Input Range 0 V

Input Leakage Current ±0.1 µA

Conversion Time 13 ADCCLK cycles at 2MHz 6.5 µs

Input Capacitance 14 pF

Track-and-Hold Acquisition Time

Turn-On Time Eight ADCCLK cycles at 2MHz 4 µs

Conversion Clock

Conversion Rate

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

25 100 kHz

BPF

-3dB 0.1 x f

LPF

±0.4 ppmFS/°C

Three ADCCLK c ycles at 2MH z 1.5 µs

0.5 4 MHz

ADCCLK

One decade awa y from center frequency

Measurement 12

No missing codes 11

Unipolar 0 V

Bipolar -V

f tested)

= 4MH z (not production

ADCCLK

-60 dB

/2 +V

REF

250 ksp s

kHz

BPF

ksps

BPF

kHz

BPF

ksps

BPF

REF

AVDD

Bits

RMS

MAXQ7667

16-Bit, RISC, Microcontroller-Based, Ultrasonic Distance-Measuring System

4 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

DVDDIO

= +5V, V

AVDD

= +3.3V; V

DVDD

= +2.5V, system clock (f

SYSCLK

) = 16MHz, burst frequency (f

BURST

) = bandpass frequency

BPF

) = 50kHz, C

REFBG

= C

REF

= 1µF in parallel with 0.01µF, f

ADCCLK

= 2MHz (SAR data rate = 125ksps), TA= T

MIN

to T

MAX

, unless

otherwise specified. Typical values are at T

= +25°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

REFERENCE BUFFER

Offset 5mV

Minimum Load 2.5 kΩ

Output Bypass Capacitor 0.47 µF

EXTERNAL VOLTAGE REFERENCE (Reference Buffer Disabled)

Reference Input Range Applied at REF 1.0 V

Reference Input Impedance

INTERNAL VOLTAGE REFERENCE (REFBG)

Initial Accuracy 2.45 2.5 2.55 V

Maximum Temperature Coefficient

Output Impedance 1.1 kΩ

Power-Supply Rejection Ratio V

Output Noise 0.5 mV

PROGRAMMABLE BURST-FREQUENCY OSCILLATOR

Burst-Frequency Range 0.025 1.335 MHz

Burst-Frequency Resolution 0.1 %

Burst-Frequency Locking Time

CRYSTAL OSCILLATOR

Frequency Range

Temperature Stability Excluding crystal 25 ppm/°C

Startup Time 16MHz crystal 10 ms

XIN Input Low Voltage When driven with external clock source

XIN Input High Voltage When driven with external clock source

INTERNAL RC OSCILLATOR

Frequency 13.5 MHz

Initial Accuracy 10.5 %

Temperature Drift TA = T

Supply Rejection V

Measured at REF with the SAR and sigma-delta ADCs running at maximum frequency

= 3.0V to 3.6V 60 dB

AVDD

Change from 40kHz to 60kHz 5

Change from 50kHz to 50.5kHz 2

Tested crystal frequency 16

Minimum crystal frequency 4

External clock input 4 16

to T

MIN

MAX

= 2.25V to 2.75V -1.5 %

DVDD

0.7 x

DVDD

50 kΩ

100 ppm/°C

700 ppm

AVDD

0.3 x

DVDD

RMS

MHz

MAXQ7667

16-Bit, RISC, Microcontroller-Based,

Ultrasonic Distance-Measuring System

_______________________________________________________________________________________ 5

ELECTRICAL CHARACTERISTICS (continued)

DVDDIO

= +5V, V

AVDD

= +3.3V; V

DVDD

= +2.5V, system clock (f

SYSCLK

) = 16MHz, burst frequency (f

BURST

) = bandpass frequency

BPF

) = 50kHz, C

REFBG

= C

REF

= 1µF in parallel with 0.01µF, f

ADCCLK

= 2MHz (SAR data rate = 125ksps), TA= T

MIN

to T

MAX

, unless

otherwise specified. Typical values are at T

= +25°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Adjustable Frequency Range Using the RCTRM register -40 +40 %

Frequency Adjustment Resolution

SUPPLY VOLTAGE SUPERVISORS

DVDD Reset Threshold

DVDD Interrupt Threshold

Minimum Reset and Interrupt Threshold Difference

AVDD Interrupt Threshold

DVDDIO Interrupt Threshold

Supervisor Operating Range At DVDD 1.5 2.75 V

Supervisor Hysteresis 1%

RESET Release Delay

Power-Up Time

Asserts RESET if V this threshold

Generates an interrupt if V below this threshold

After V threshold

Time from RESET is released to the execution of the first instruction (serial bootloader off)

rises above the reset

DVDD

falls below

DVDD

falls

DVDD

falls

AVDD

falls

DVDDIO

0.2 %

2.10 2.25 V

2.25 2.38 V

150 mV

2.95 3.15 V

4.5 4.75 V

35 µs

1µs

+5V LINEAR REGULATOR (DVDDIO, GATE5, Requires External Pass Transistor, see the Typical Application Circuit/Functional Diagram)

Regulator Output Voltage At DVDDIO 4.75 5.25 V

GATE5 Output High Voltage I

GATE5 Output Low Voltage I

GATE5 Output Resistance I

Gain Bandwidth DVDDIO to GATE5 1.58 kHz

Gain DVDDIO to GATE5 1700 V/V

GATE5 Slew Rate 4.3 V/ms

Maximum Load Capacitance

+3.3V LINEAR REGULATOR (REG3P3)

REG3P3 Output Voltage 3.15 3.45 V

Load Current 50 mA

Output Short-Circuit Current REG3P3 shorted to AGND 150 mA

Maximum capacitance on DVDDIO when using an external pass transistor

= 0µA (no load)

SOURCE

= 500µA 2 V

SINK

= 0µA to 50µA 330 Ω

SINK

DVDDIO

- 0.1

1µF

MAXQ7667

16-Bit, RISC, Microcontroller-Based, Ultrasonic Distance-Measuring System

6 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

DVDDIO

= +5V, V

AVDD

= +3.3V; V

DVDD

= +2.5V, system clock (f

SYSCLK

) = 16MHz, burst frequency (f

BURST

) = bandpass frequency

BPF

) = 50kHz, C

REFBG

= C

REF

= 1µF in parallel with 0.01µF, f

ADCCLK

= 2MHz (SAR data rate = 125ksps), TA= T

MIN

to T

MAX

, unless

otherwise specified. Typical values are at T

= +25°C.)

SPI is a trademark of Motorola, Inc.

+2.5V LINEAR REGULATOR (REG2P5)

REG2P5 Output Voltage 2.38 2.62 V

Load Current 50 mA

Output Short-Circuit Current REG2P5 shorted to DGND 100 mA

POWER REQUIREMENTS

Supply Voltage Range

AVDD Supply Current

DVDD Supply Current 11 mA

DVDDIO Supply Current 2.5 mA

DIGITAL INPUTS (GPIO, UART, JTAG, SPI™)

Input High Voltage

Input Low Voltage 0.8 V

Input Hysteresis V

Input Leakage Current

Pullup/Pulldown Resistance

Input Capacitance 15 pF

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

DVDD 2.25 2.5 2.75

AVDD 3.00 3.3 3.6

DVDDIO 4.5 5.0 5.5

All analog functions enabled 12 18 mA

All analog functions disabled 3 10 µA

Incremental AVDD supply current

= 5.0V 500 mV

DVDDIO

Digital input voltage = DGND or DVDDIO, pullup disabled

Pulled up to DVDDIO internal ly, pulled down to DGND internally

LNA 2.4

Sigma-delta ADC 12

SAR ADC, 250ksps, f

PLL 300

Supply vo ltage supervisors

Internal voltage reference

Reference buffer 300

Bias (any AVDD module enabled)

ADCCLK

= 4MHz

600

220

1.5 mA

DVDDIO

- 1

±0.01 ±1 µA

150 k

µA

MAXQ7667

16-Bit, RISC, Microcontroller-Based,

Ultrasonic Distance-Measuring System

_______________________________________________________________________________________ 7

ELECTRICAL CHARACTERISTICS (continued)

DVDDIO

= +5V, V

AVDD

= +3.3V; V

DVDD

= +2.5V, system clock (f

SYSCLK

) = 16MHz, burst frequency (f

BURST

) = bandpass frequency

BPF

) = 50kHz, C

REFBG

= C

REF

= 1µF in parallel with 0.01µF, f

ADCCLK

= 2MHz (SAR data rate = 125ksps), TA= T

MIN

to T

MAX

, unless

otherwise specified. Typical values are at T

= +25°C.)

DIGITAL OUTPUTS (GPIO, UART, JTAG, SPI)

Output Low Voltage

Output High Voltage

Maximum Output Impedance

Three-State Leakage ±0.01 ±1 µA

Three-State Capacitance 15 pF

BURST OUTPUT

Output Low Voltage I

Output High Voltage I

Maximum Output Impedance

Three-State Leakage ±0.01 ±1 µA

Three-State Capacitance 15 pF

Short-Circuit Current Burst drive set to high 50 mA

RESET

Internal Pullup Resistance Pulled up to DVDDIO 120 k

Output Low Voltage I

Output High Voltage No external load

Input Low Voltage When driven by external source 0.8 V

Input High Voltage When driven by external source

UART/LIN INTERFACE (UTX, URX)

UART Baud Rates

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

= 0.5mA, drive strength = low 0.4

SINK

= 1.0mA, drive strength = high 0.4

SINK

I drive strength = low

SOURCE

drive strength = high

Drive strength = low 880

Drive strength = high 450

Drive strength = low 90

Drive strength = high 45

Asynchronous mode (system clock/32)

Synchronous mode (system clock/8) 2000

LIN 2.0 compatibility (Note 3) 1 20

= 0.5mA,

SOURCE

= 1.0mA,

= 8mA 0.4 V

SINK

= 8mA

SOURCE

= 0.5mA 0.4 V

SINK

DVDDIO

0.5

DVDDIO

0.5

DVDDIO

0.5

DVDDIO

0.5

DVDDIO

500



kbps

MAXQ7667

16-Bit, RISC, Microcontroller-Based, Ultrasonic Distance-Measuring System

8 _______________________________________________________________________________________

Note 1: Noise measured at bandpass filter output with ECHO+ and ECHO- shorted divided by the gain with f

BPF

= 50kHz.

Note 2: Gain adjust resolution typically ranges between 6.25% and 12.5%. Note 3: LIN 2.0 specifies a maximim data rate of 20kbps. Higher data rates could be possible with compatible devices and suitable

line conditions.

ELECTRICAL CHARACTERISTICS (continued)

DVDDIO

= +5V, V

AVDD

= +3.3V; V

DVDD

= +2.5V, system clock (f

SYSCLK

) = 16MHz, burst frequency (f

BURST

) = bandpass frequency

BPF

) = 50kHz, C

REFBG

= C

REF

= 1µF in parallel with 0.01µF, f

ADCCLK

= 2MHz (SAR data rate = 125ksps), TA= T

MIN

to T

MAX

, unless

otherwise specified. Typical values are at T

= +25°C.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

SPI INTERFACE TIMING (Figures 11 and 12)

SPI Master Operating Frequency

SPI Slave Operating Frequency

SCLK Output Pulse-Width High/Low

MOSI Output Hold Time After SCLK Sample Edge

MOSI Output Valid to Sample Edge

MISO Input Valid to SCLK Sample Edge

MISO Input Hold Time After SCLK Sample Edge

SCLK Inactive to MOSI Inactive

SCLK Input Pulse-Width High/Low

SS Active to First Shift Edge t

MOSI Input Setup Time to SCLK Sample Edge

MOSI Input Hold Time After SCLK Sample Edge

MISO Output Valid After SCLK Shift Edge Transition

SS Inactive Duration t

SCLK Inactive to SS Rising Edge

1/t

MCH

MCL

MOH

MOV

MIS

MIH

MLH

SCH

SCL

SSE

SIH

SOV

SSH

MCK

SCK

SIS

0.5 x f

0.25 x f

SYSCLK

8 MHz

4 MHz

MCK

- 25

MCK

- 25

MCK

- 25

25 ns

0ns

/2 ns

SCK

SYSCLK

25 ns

50 ns

SYSCLK

FLASH PROGRAMMING

Flash Erase Time

Mass erase 200

Page erase (512 bytes per page) 20

Flash Programming Time 20µs per word 657 ms

Write/Erase Cycles 10,000 Cycles

Data Retention Average temperature = +85°C 15 Years

MAXQ7667

16-Bit, RISC, Microcontroller-Based,

Ultrasonic Distance-Measuring System

_______________________________________________________________________________________ 9

Typical Operating Characteristics

DVDDIO

= +5V, V

AVDD

= +3.3V, V

DVDD

= +2.5V, f

SYSCLK

= 16MHz, burst frequency = bandpass frequency = 50kHz, TA= +25°C,

unless otherwise noted.)

BURST OUTPUT FREQUENCY

vs. TEMPERATURE

50.05 USING PLL

50.04

50.03

50.02

50.01

50.00

49.99

49.98

49.97

BURST OUTPUT FREQUENCY (kHz)

49.96

49.95

-50 125 TEMPERATURE (°C)

5025 100750-25

BANDPASS FILTER OUTPUT NOISE FLOOR

vs. BANDPASS FILTER CENTER FREQUENCY

RECEIVE PATH GAIN AT MAXIMUM

)

RMS

TA = +105°C

BANDPASS FILTER OUTPUT (LSB

20 100

LOWPASS FILTER OUTPUT RIPPLE vs. TIME

15,000

14,500

14,000

13,500

13,000

12,500

12,000

LPF OUTPUT (LSB)

11,500

MINIMUM ECHO GAIN

11,000

20mV 50kHz ECHO FREQUENCY

10,500

250ksps

10,000

012

65,536

57,344

MAXQ7667 toc01

49,152

40,960

32,768

24,576

LPF OUTPUT (LSB)

16,384

TA = +25°C

FREQUENCY (kHz)

ECHO AMPLITUDE

P-P

246 108

TIME (ms)

LOWPASS FILTER OUTPUT

vs. ECHO INPUT AMPLITUDE

PROGRAMMABLE ECHO GAIN = MINIMUM

8192

0 0.10

TA = -40°C

806040

0.040.02 0.080.06

ECHO INPUT AMPLITUDE (V

MAXQ7667 toc04

MAXQ7667 toc06

P-P

16,000

14,000

12,000

10,000

ADC COUNT (LSB)

OFFSET ERROR (mV)

LOWPASS FILTER OUTPUT

vs. ECHO INPUT FREQUENCY

100,000

PROGRAMMABLE ECHO GAIN = MINIMUM ECHO INPUT AMPLITUDE = 20mV

MAXQ7667 toc02

10,000

1000

LPF OUTPUT (LSB)

100

25 100

)

ECHO INPUT FREQUENCY (kHz)

RECEIVE PATH RESPONSE TIME

(ECHO INPUT TO LOWPASS FILTER OUTPUT)

MINIMUM ECHO GAIN

ECHO AMPLITUDE

20mV

P-P

50kHz ECHO FREQUENCY

8000

6000

4000

2000

INPUT ON

0 1000

400200 800600

TIME (µs)

250ksps

INPUT OFF

SAR ADC OFFSET ERROR

vs. TEMPERATURE

2.0

1.5

1.0

0.5

-0.5

-1.0

-50 125

= 3.6V

AVDD

= 3.3V

AVDD

07525-25 10050

TEMPERATURE (°C)

AVDD

= 3V

P-P

MAXQ7667 toc03

5540 8570

MAXQ7667 toc05

MAXQ7667 toc07

MAXQ7667

16-Bit, RISC, Microcontroller-Based, Ultrasonic Distance-Measuring System

10 ______________________________________________________________________________________

Typical Operating Characteristics (continued)

DVDDIO

= +5V, V

AVDD

= +3.3V, V

DVDD

= +2.5V, f

SYSCLK

= 16MHz, burst frequency = bandpass frequency = 50kHz, TA= +25°C,

unless otherwise noted.)

GAIN ERROR (mV)

SAR ADC GAIN ERROR

vs. TEMPERATURE

3.0

2.5

2.0

1.5

1.0

0.5

-50 125

AVDD

= 3.6V

AVDD

07525-25 10050

TEMPERATURE (°C)

= 3.3V

AVDD

= 3V

MAXQ7667 toc08

INL (LSB)

-0.5

-1.0

-1.5

-2.0

SAR ADC INL vs. CODE

2.0

1.5

1.0

0.5

0409625601536512 3584

CODE

2.0

1.5

MAXQ7667 toc09

1.0

0.5

DNL (LSB)

-0.5

-1.0

-1.5

307220481024

-2.0 0 409625601536512 3584

SAR ADC DNL vs. CODE

MAXQ7667 toc10

307220481024

CODE

REFERENCE OUTPUT VOLTAGE

vs. SUPPLY VOLTAGE

2.520

2.519

2.518

2.517

2.516

2.515

REF OUTPUT VOLTAGE (V)

2.514

2.513

2.512

3.0 3.63.1 3.4 AVDD SUPPLY VOLTAGE (V)

SUPPLY BROWNOUT THRESHOLDS

vs. TEMPERATURE

5.0

4.5

4.0

3.5

3.0

SUPPLY THRESHOLD (V)

2.5

DVDDIO INTERRUPT

AVDD INTERRUPT

DVDD INTERRUPT

3.53.33.2

DVDD RESET

MAXQ7667 toc11

MAXQ7667 toc13

REFERENCE OUTPUT VOLTAGE

vs. TEMPERATURE

2.55

2.53

2.51

2.49

REF OUTPUT VOLTAGE (V)

2.47

2.45

-50 12550-25

025 10075

TEMPERATURE (°C)

REGULATOR OUTPUT VOLTAGE

vs. TEMPERATURE

5.0

4.5

4.0

3.5

3.0

REGULATOR OUTPUT VOLTAGE (V)

2.5

DVDDIO

AVDD

DVDD

MAXQ7667 toc12

MAXQ7667 toc14

2.0

-50 12550

TEMPERATURE (°C)

25 1000-25 75

2.0 25 1000-25 75-50 12550

TEMPERATURE (°C)

MAXQ7667

16-Bit, RISC, Microcontroller-Based,

Ultrasonic Distance-Measuring System

______________________________________________________________________________________

Typical Operating Characteristics (continued)

DVDDIO

= +5V, V

AVDD

= +3.3V, V

DVDD

= +2.5V, f

SYSCLK

= 16MHz, burst frequency = bandpass frequency = 50kHz, TA= +25°C,

unless otherwise noted.)

DVDDIO REGULATOR OUTPUT VOLTAGE

5.5

5.0

4.5

4.0

3.5

EXTERNAL VOLTAGE SOURCE CONNECTED TO THE DRAIN OF EXTERNAL PASS

DVDDIO REGULATOR OUTPUT VOLTAGE (V)

TRANSISTOR BSP129

3.0

0 200150

REG2P5 REGULATOR OUTPUT VOLTAGE

3.0

2.5

2.0

vs. LOAD CURRENT

DRAIN = 14V

DRAIN = 8V

10050

DVDDIO LOAD CURRENT (mA)

vs. LOAD CURRENT

REG3P3 REGULATOR OUTPUT VOLTAGE

vs. LOAD CURRENT

3.5

MAXQ7667 toc15

3.0

2.5

2.0

1.5

1.0

0.5

REG3P3 REGULATOR OUTPUT VOLTAGE (V)

0 12010020 80

REG3P3 LOAD CURRENT (mA)

6040

RC OSCILLATOR FREQUENCY

vs. TEMPERATURE

15.0

MAXQ7667 toc17

14.5

14.0

MAXQ7667 toc16

MAXQ7667 toc18

1.5

1.0

0.5

REG2P5 REGULATOR OUTPUT VOLTAGE (V)

012010020 80

REG2P5 LOAD CURRENT (mA)

6040

13.5

= 2.50V

= 2.75V

DVDD

07525-25 10050

TEMPERATURE (°C)

DVDD

13.0

RC OSCILLATOR FREQUENCY (MHz)

12.5

12.0

-50 125

DVDD

= 2.25V

MAXQ7667

16-Bit, RISC, Microcontroller-Based, Ultrasonic Distance-Measuring System

12 ______________________________________________________________________________________

Pin Description

PIN NAME FUNCTION

1 P1.3/TCK

2 P1.4/MOSI

3 P1.5/MISO

4 P1.6/SCLK

5 P1.7/SYNC/SS

6, 19, 42 DVDD

7, 18, 43 DGND Digital Ground. Connect all DGND nodes together. Connect to AGND at a si ngle point.

8, 17, 44 DVDDIO

9 P0.0/URX

10 P0.1/UTX

11 P0.2/TXEN

13 P0.4/T0B

14 P0.5/T1

15 P0.6/T2

16 P0.7/T2B

20 XIN

P0.3/T0/

ADCCTL

Port 1 Data 3/JTAG Serial Clock Input. P1.3 i s a general-purpose digital I/O. TCK is the JTAG serial test clock input. Refer to the MAXQ7667 User’s Guide Sections 5 and 11.

Port 1 Data 4/SPI Serial Data Output. P1.4 is a general-purpose digital I/O. MOSI is the master output, sla ve input for the SPI interface. Refer to the MAXQ7667 User’s Guide Sections 5 and 9.

Port 1 Data 5/SPI Serial Data Input. P1.5 is a general-purpose digital I/O. MISO is the ma ster input, slave output for the SPI interface. Refer to the MAXQ7667 User’s Guide Sections 5 and 9.

Port 1 Data 6/SPI Serial Clock Output. P1.6 is a general-purpose digital I/O. SCLK is the serial clock for the SPI interface. SCLK is an input when operating as a s lave and an output when operating as a master. Refer to the MAXQ7667 User’s Guide Sections 5 and 9.

Port 1 Data 7/Schedule Timer Sync Input/SPI Slave Select. P1.7 is a general-purpose digital I/O. A rising edge on the SYNC input resets the schedule timer. In SPI slave mode, SS is the SPI slave-select input. In SPI master mode, use SS or a GPIO to manually select an external slave. Refer to the MAXQ7667 User’s Guide Sections 5, 7, and 9.

Digital Supply Voltage. Connect DVDD directly to a +2.5V external source or to REG2P5 output for single supply operation. B ypass DVDD to DGND with a 0.1µF capacitor as clo se a s possible to the device. Connect all DVDD nodes together.

Digital I/O Supply Voltage. DVDDIO powers al l digital I/Os except for XIN and XOUT. Bypass DVDDIO to DGND with a 0.1µF capacitor as close as possible to the device. Connect all DVDDIO nodes together.

Port 0 Data 0/UART Rece ive Data Input. P0.0 is a general-purpose digital I/O. URX is a UART or LIN data receive input. Refer to the MAXQ7667 User ’s Guide Sections 5 and 8.

Port 0 Data 1/UART Transm it Data Output. P0.1 i s a general-purpose digital I/O. UTX is a UART or LIN data transmit output. Refer to the MAXQ7667 User’s Guide Sections 5 and 8.

Port 0 Data 2/UART Transm it Output. P0.2 is a general-purpose digital I/O. TXEN asserts low when the UART is transmitting. Use TXEN to enable an e xternal LIN/UART transcei ver. Refer to the MAXQ7667 U ser’ s Guide Sections 5 and 8.

Port 0 Data 3/Timer 0 I/O/ADC Control Input. P0.3 is a general-purpose digital I/O. T0 is the primary Type 2 timer/counter 0 output or input. ADCCTL is a sampling/conversion trigger input for the SAR ADC. Refer to the MAXQ7667 User ’s Guide Sections 5, 6, and 14.

Port 0 Data 4/Timer 0B I/O/Comparator Output. P0.4 is a general-purpose d igital I/O. T0B is the secondary Type 2 timer/counter 0 output or input. Refer to the MAXQ7667 User’s Guide Sections 5 and 6.

Port 0 Data 5/Timer 1 I/O. P0.5 is a general-purpose digital I/O. T1 is the primary Type 2 timer/counter 1 output or input. Refer to the MAXQ7667 User’s Guide Sections 5 and 6.

Port 0 Data 6/Timer 2 I/O. P0.6 is a general-purpose digital I/O. T2 is the primary Type 2 timer/counter 2 output or input. Refer to the MAXQ7667 User’s Guide Sections 5 and 6.

Port 0 Data 7/Timer 2B I/O. P0.7 is a general-purpose digital I/O. T2B is the secondary Type 2 timer/counter 2 output or input. Refer to the MAXQ7667 User’s Guide Sections 5 and 6.

Crystal Oscillator Input. Connect an external crystal or resonator between XIN and XOUT. When using an external clock source drive XIN with 2.5V level clock while leaving XOUT unconnected. Connect XIN to DGND when an external clock source i s not used.

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