Nokia 2112, rh57 System Module

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Nokia Customer Care

2112 (RH-57) Series Transceivers

System Module

2112 (RH-57) System Module Nokia Customer Care

Contents Page

Introduction ..................................................................................................................................................... 3

Baseband Module ........................................................................................................................................ 3

UEM .............................................................................................................................................................. 4

BB-RF Interface Connections ...................................................................................................................6

UPP................................................................................................................................................................ 9

NOR Flash Memory and SRAM .......................................................................................................... 10

User Interface Hardware .........................................................................................................................10

LCD............................................................................................................................................................. 10

Keyboard................................................................................................................................................... 11

Power Key ................................................................................................................................................ 11

Lights......................................................................................................................................................... 11

Flashlight.................................................................................................................................................. 11

Vibra .......................................................................................................................................................... 11

Audio Hardware .........................................................................................................................................12

Earpiece .................................................................................................................................................... 12

Microphone ............................................................................................................................................. 12

MIDI Speaker........................................................................................................................................... 12

Audio Amplifier Interface.................................................................................................................... 12

Battery ..........................................................................................................................................................12

Battery Connector ................................................................................................................................. 13

Accessories Interface ................................................................................................................................14

System Connector.................................................................................................................................. 14

Charger IF................................................................................................................................................. 16

Test Interfaces ............................................................................................................................................16

Production Test Pattern ....................................................................................................................... 16

General Information About Testing ......................................................................................................19

Phone Operating Modes ...................................................................................................................... 19

RF Module ....................................................................................................................................................19

Requirements .......................................................................................................................................... 19

Antenna .................................................................................................................................................... 19

Transmitter .............................................................................................................................................. 20

Synthesizer .............................................................................................................................................. 22

Receiver ................................................................................................................................................... 24

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Introduction

The 2112 is available as a CDMA single-band engine (800 MHz CDMA). There are several different operational modes, which have different states controlled by the cellular SW. Some examples include:

• Idle State (on ACCH)

• Camping (on DCCH)

• Scanning

•Conversation

• No Service Power Save (NSPS)

In the power-off mode, only the circuits needed for power-up are supplied.

In the idle mode, circuits are powered down and only the sleep clock is running.

In the active mode, all the circuits are supplied with power, although some parts might be in idle state part of the time.

The charge mode is effective in parallel with all previous modes. The charge mode itself consists of two different states, the fast charge and the maintenance mode.

The Local Mode is used for alignment and testing.

Baseband Module

The baseband module is an 800 MHz CDMA DCT4 transceiver based on the DCT4 Apollo engine. The baseband consists of three ASICs:

• Universal Energy Management (UEM)

• Universal Phone Processor (UPP)

• 64-megabit FLASH

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PA Supply

RF Supplies

Apollo

BATTERY

RF RX/TX

RFIC CTRL 19.2 MHz

UEM

Ear

MIC

Buzzer

Vibra

MEMADDA MEMCONT

FLASH

UPP

PURX

RF RX/TX

Sleep Clock 32 kHz

CBUS/DBUS

AUDIO

BB Supplies

UEM

External Audio

Charger

Connection

DCT4 System

Connector

Figure 1: Baseband module diagram

The UEM is the Universal Energy Management IC for DCT4 digital handportable phones. In addition to energy management, it performs all the baseband mixed-signal functions.

Most UEM pins have 2kV ESD protection. Those signals that are considered to be exposed more easily to ESD have 8kV protection inside the UEM. Such signals are all audio, headset, BSI, Btemp, Fbus, and Mbus signals.

The baseband is powered from five different UEM regulators.

Table 1: Baseband Regulators

Regulator

Maximum Current (mA)

Vout (V) Notes

VCORE 300 1.57/1.35 Power up default 1.57V and 1.35 in Sleep Mode.

VIO 150 1.8 Enabled always except during power-off mode

VFLASH1 70 2.78 Enabled always except during power-off mode

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Table 1: Baseband Regulators (Continued)

Regulator

VFLASH2 40 2.78 Enabled only when data cable is connected

VANA 80 2.78 Enabled only when the system is awake (Off

VSIM 25 3.0 Enabled only when SIM card is used

Maximum Current (mA)

Vout (V) Notes

during sleep and power off-modes)

Table 2 includes the UEM regulators for the RF.

Table 2: RF Regulators

Regulator

VR1A 10 4.75 Enabled when cell transmitter is on

VR1B 10 4.75 Enabled when the transmitter is on

VR2 100 2.78 Enabled when the transmitter is on

VR3 20 2.78 Enabled when SleepX is high

VR4 50 2.78 Enabled when the receiver is on

Maximum Current (mA)

Vout (V) Notes

VR5 50 2.78 Enabled when the receiver is on

VR6 50 2.78 Enabled when the transmitter is on

VR7 45 2.78 Enabled when the receiver is on

The charge pump that is used by VR1A is constructed around the UEM. The charge pump works with the Cbus (1.2 MHz) oscillator and gives a 4.75 V regulated output voltage to the RF.

RF Interface

In addition to the RF regulators mentioned, the UEM handles the interface between the baseband and the RF section. It provides A/D and D/A conversion of the in-phase and quadrature receive and transmit signal paths, and also A/D and D/A conversions of received and transmitted audio signals to and from the UI section. The UEM supplies the analog AFC signal to the RF section according to the UPP DSP digital control. It also converts the PA temperature into real data for the DSP. The UPP controls the RFIC through the 3-wire RFIC bus. In addition, the UPP provides a PDM regulator for RF interface (RX/TX AGC control).

Charging Control

The CHACON block of the UEM controls charging. Needed functions for charging controls are the PWM-controlled battery charging switch, charger-monitoring circuitry, battery voltage monitoring circuitry, and RTC supply circuitry for backup battery charging. In

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addition, external components are needed for EMC protection of the charger input to the baseband module. The DCT4 baseband is designed to electrically support both DCT3 and DCT4 chargers.

Digital Interface

Data transmission between the UEM and the UPP is implemented using two serial connections: DBUS (9.6 MHz) for the DSP and CBUS (1.2 MHz in CDMA) for the MCU. The UEM is a dual-voltage circuit. The digital parts run from 1.8 V and the analog parts run from 2.78 V. The Vbat (3.6 V) voltage regulator inputs are also used.

Audio Codec

The baseband supports two external microphone inputs and one external earphone output. The inputs can be taken from an internal microphone, from a headset microphone, or from an external microphone signal source through a headset connector. The output for the internal earpiece is a dual-ended output, and the differential output is capable of driving 4Vpp to the earpiece with a 60 dB minimum signal to total distortion ratio. Input and output signal source selection and gain control is performed inside the UEM ASIC according to control messages from the UPP. Both the buzzer and external vibra alert control signals are generated by the UEM with separate PWM outputs.

MIDI

The MIDI audio signal generated by the DSP and UEM audio CoDec is routed to the XEAR output of the UEM. An audio amplifier (LM4890) is used to boost enough power for the speaker.

UI Drivers

The vibra, display LED, and keyboard LEDs are driven by open collector output drivers inside the UEM. These drivers can generate PWM square wave signals to these devices.

AD Converters

There is an 11-channel analog-to-digital converter in the UEM. The AD converters are calibrated in the production line.

BB-RF Interface Connections

All the signal descriptions and properties in the following tables are valid only for active signals.

Signal Name

From To Parameter Min Type Max Unit Function

Table 3: PDM Interface

RX_IF_AGC UPP

GenIO 9

Yoda Voltage Min

Max

-------------Clk Rate

(1)

0.0

1.75

------

1.8

----

9.6

0.1

1.86

-----

19.2

----MHz

Controls gain of VGA r in receiver

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Table 3: PDM Interface (Continued)

Signal Name

TX_IF_AGC UPP

TX_RF_AGC UPP

Signal Name

TX_Gate UPP

From To Parameter Min Type Max Unit Function

GenIO 7

GenIO 26

From To Parameter

Gen IO 8 pullup

Jedi Voltage Min

Max

-------------Clk Rate

Jedi Voltage Min

Max

-------------Clk Rate

Jedi and PA Gating Transistors

(1)

(3)

Table 4: General I/O Interface

“0” Transmitter Off “1” Transmitter On Timing Accuracy

0.0

1.75

-----

0.0

1.75

------

0.1

1.8

-----

9.6

1.8

-----

9.6

1.86

-----

19.2

0.1

1.86

------

19.2

Input Characteristics

1.38 1.88 V 0 0.4 V 4 chips, and can be up to a total of 255 chips

----MHz

Controls gain of VGA in IF VGA

Controls gain of TX driver

Function

Punctures the PAs and the Jedi ASIC

Digital Into RF

D0 UPP

Gen IO 10

D1 UPP

Gen IO 13

D2 UPP

Gen IO 12

Signal Name

19.2M_UPP Yoda UPP Frequency

AFC UEM VCT

From To Parameter Min Type Max Unit Function

PMIC Voltage Min

-------------Signal amplitude

Voltage Min

CXO

Max

--------------Settling time

0.4V max

Max

Table 5: VCTCXO Interface

-----

0.5

0.0

2.4

------ -----

(4)

1.72V-1.86V

0.4V max

1.72V-1.86V

0.4V max

1.72V-1.86V

19.2

-----

1.0

-----

1.5

0.1

2.55

-----

0.2

Enable PMIC

Set PMIC output voltage

MHz

----Vpp

----ms

High stability clock signal for logic circuits, AC coupled sinewave.

Automatic frequency control signal for VCTCXO Digital Into RF

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Table 6: Regulated Supplies from UEM to RF

Signal Name

VBAT Battery PA &

VR1A UEM PA Vref Voltage

VR2 UEM Jedi Voltage

VR3 UEM VCTCXO,

VR4 UEM Alfred Voltage

VR5 UEM Jedi Voltage

From To Parameter Min Type Max Unit Function

Voltage UEM, external driver amps

Yoda

-------------

Current

-------------

Current

-------------

Current

Voltage

-------------

Current

-------------

Current

-------------

Current

3.2

----0

4.6

----0

2.70

-----

2.70

-----

2.70

-----

2.70

-----

3.5

-----

4.75

----4

2.78

-----

2.78

-----

2.78

-----

2.78

-----

5.1

----2A peak

4.9

----5

2.86

----100

2.8

----20

-----

----mA

Battery supply. Lower limit is to guarantee regulator PSRR

Charge pump + linear regulator.

Linear regulator

Low noise linear regulator for VCTCXO

Low lq linear regulator

VR6 UEM Yoda Voltage

-------------

Current

VR7 UEM Jedi Voltage

-------------

Current

VIO UEM Jedi,

Yoda

Vref_rf01 UEM Yoda Voltage 1.334 1.35 1.366 V Voltage refer for Yoda

Signal Name

PA_TEMP Thermistor UEM Input voltage

PWROUT Jedi UEM Input voltage

From To Parameter Min Type Max Unit Function

Voltage 1.70 1.8 1.88

Table 7: Slow A/D Converters

range

2.70

------

2.70

------

0 2.78 V PA temperature sen-

0 2.78 V Buffered output of TX

2.78

-----

2.78

-----

-----50

----mA

Low lq linear regulator

Low noise linear regulator for synthesizer

Supply for RF-BB digital signal interface and some digital parts of RF

I/or de-modulator

sor output voltage Analog Out of RF

output detector

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Table 8: RF-BB Analog Signals

Signal Name

RX_IP_RF RX_IN_RF RX_QP_RF RX_QN_RF

TX_IP_RF TX_IN_RF TX_QP_RF TX_QN_RF

Signal Name

RF_BUS_CLK RF_BUS_DATA RF_BUS_EN1X

From To Parameter Min Type Max Unit Function

Yoda UEM Differential volt-

age swing (static)

--------------DC level

--------------Input Bandwidth

UEM Jedi Differential volt-

age swing (static)

----------------DC level

-----------------

-3 dB Bandwidth

Table 9: RFIC Control

0.3

-----

1.3

-----

0.4

-----

1.65

----650

0.5

-----

1.35

-----

0.8

----

1.7

----

1.0

-----

1.4

----615

1.2

----

1.75

----1950

Vpp

---V

---kHz

Vpp

---V

---kHz

Differential in-phase and quadrature RX baseband signal

Analog Out of RF

Differential quadrature phase TX baseband signal for RF modulator

Analog into RF

From To Parameter Min Type Max Unit Function

UPP Jedi,

Yoda

High-level input

voltage, V

Low-level input

voltage, V

1.72

1.8

1.86

0.4

Serial Clock = Digital Into RF

Bidirectional Serial Date = Digital I/O

UPP

High-level out-

put voltage, V

Low-level out-

put voltage, V

Clock

1.72

1.8

9.6

1.86

0.4

MHz

Latch enable for Jedi and Yoda = Digital Into RF

The 2112 uses a UPP8Mv3.5 ASIC with an 8Mbit RAM size. The UPP ASIC is designed to operate in a DCT4 engine, and is designed as part of the DCT4 common baseband task force. The DCT4 processor architecture consists of both DSP and MCU processors.

The UPP is internally partitioned into two main parts: the Brain and the Body.

The Brain consists of the processor and memory system (i.e., processor cores, mega-cells, internal memories, peripherals, and the external memory interface). The following blocks are included:

• DSP Subsystem (DSPSS)

• MCU Subsystem (MCUSS)

• Emulation control EMUCtl

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• Program/data RAM PDRAM

• Brain Peripherals–subsystem (BrainPer)

The Body consists of the NMP custom cellular logic functions. These contain all interfaces and functions needed for interfacing with other DCT4 baseband and RF parts. The following sub-blocks are included:

•MFI

•SCU

•CTSI

•RxModem

• AccIF

•UIF

•Coder

• GPRSCip

•BodyIF

• SIMIF

•PUP

• CDMA (Corona)

NOR Flash Memory and SRAM

This device is a 64Mbit, mixed burst, multi-bank Flash and 8Mbit Muxed fCMOS SRAM combined in a multi-chip package memory.

The 64Mbit Flash memory is organized as 8M x 16 bit, and the 8Mbit SRAM is organized as 512K x 16 bit. The Flash memory architecture is designed to divide its memory arrays into 263 blocks, which provides highly flexible erase and program capability. This device is capable of reading data from one bank while programming or erasing in the other banks with multi-bank organization.

The Flash memory performs a program operation in units of 16 bits (Word) and erases in units of a block. Single or multiple blocks can be erased. The block erase operation is completed for typically 0.7 sec.

The 8Mbit Muxed fCMOS SRAM supports low data retention voltage for the battery backup operation with a low data retention current.

User Interface Hardware

LCD

The 2112 uses a black and white, 96 X 65 display. The LCD is controlled by UI SW and control signals.

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Keyboard

The keyboard design is a 4-way scroll with navigation keys, two soft keys, and 12 number keys. The power key is located on top.

Power Key

All signals for the keyboard come from the UPP ASIC, except the power key signal, which is connected directly to the UEM. Pressing the power key creates an interrupt and connects the PWONX to the GND.

Lights

The 2112 has six white LEDs for keyboard lighting purposes. The LEDs for the display are integrated into the display module.

Display lighting and keyboard lights are controlled by the UEM Klight signal (8-bit register DriverPWMR, bits 7...4). The Klight output is a Pulse Width Modulation (PWM) signal, which is used to control the average current going through the LEDs. A step-up converter and a constant current source are used to ensure that the LEDs provide uniform intensity.

Flashlight

The flashlight feature is driven by the White LED Driver and controlled by the UEM. The circuit for the flashlight is driven by TK11851TL. In this situation, the driver is used as a boost DC/DC. Vout is set using three precision resistors in R300, R316, and 317. Vout = Vfb * (1+ (R316+R317)/ R300). The TK11851L is an active-high enable device, whose enable signal is tied to Klight/Dlight signals from the UEM. When Klight goes high it turns on the TK11851TL driver and the V301 transistor, which allows a path to GND.

Vibra

The vibra is located on the bottom of the D-cover and is connected by spring connectors on the PWB.

The vibra is controlled by a VIBRA PWM signal from the UEM. This signal allows control of both frequency and pulse width of the signal. Pulse width is used to control the current when the battery voltage changes. Frequency control searches for optimum frequency to ensure silent and efficient vibrating.

Table 10: Vibra Parameters

Parameter Requirement Unit

Rated DC voltage 1.3 V

Rated speed 9500 ± 3000 rpm

Rated current 115 ± 20 mA

Starting current 150 ± 20 mA

Armature resistant 8.6 ohm

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Table 10: Vibra Parameters (Continued)

Parameter Requirement Unit

Rated DC voltage available 1.2 to 1.7 V

Starting DC voltage min 1.2 V

Audio Hardware

Earpiece

The 2112 uses the 13 mm speaker capsule that is used in DCT3. The speaker is dynamic, very sensitive, and capable of producing relatively high sound pressure at low frequencies. The speaker capsule and surrounding mechanics comprise the earpiece.

Microphone

The microphone is an electric microphone with an omnidirectional polar pattern. It consists of an electrically polarized membrane and a metal electrode, both of which form a capacitor. Air pressure changes (i.e., sound) move the membrane, which causes voltage changes across the capacitor. Since the capacitance is typically 2 pF, a FET buffer is needed inside the microphone capsule for the signal generated by the capacitor. The microphone needs bias voltage as a result of the FET.

MIDI Speaker

Musical Instrument Digital Interface (MIDI) defines the data interchange format. By implementing a MIDI engine, enriched sound effects are achieved, which include ring tones, UI event sounds, and music for games and entertainment.

The MIDI data stream is a unidirectional, asynchronous bit stream at maximum

31.25 kbits/sec with 10 bits transmitted per byte (a start bit, 8 data bits, and one stop bit).

MIDI data includes two categories of signals: MIDI tones and Alerting Tones. Both are generated from the DSP and sent to the MIDI speaker.

Audio Amplifier Interface

Because the audio output from the UEM is not strong enough to produce enough power for the speaker, an audio amplifier is required. The MIDI audio signal generated by the DSP and UEM audio CoDec is routed to the XEAR output of the UEM. An audio amplifier is used to boost enough power for the speaker. GENIO (28) is used to enable/disable the audio amplifier as needed.

Battery

An 850 mAh Li-ion battery (BL-5C) is standard in the 2112. The battery block contains BSI resistors for battery identification. The BSI fixed resistor value indicates the chemistry and default capacity of a battery. This resistor is connected to the BSI pin of

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the battery connector. The phone has pull-up resistors (R202) for these lines so that they can be read by A/D inputs in the phone. There also are spark caps in the BSI line to prevent ESD. The battery also has internal protection for overvoltage and overcurrent.

Figure 2: Battery interface

Battery Connector

The 2112 uses a spring-type battery connector. This ensures a more reliable connection between the battery and PWB

Figure 3: Battery pack pin order

Table 11 shows the properties for the battery pack pins.

Table 11: Battery Pin Properties

Signal Name

1 VBAT (+) (batt.) VBAT I/O

2 BSI BSI (batt.) UEM Out

3 GND GND GND

Connected From - To

Batt I/O

Signal Properties A/D Levels Freq/Timing

Description

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Accessories Interface

System Connector

The 2112 uses Tomahawk accessories via the Tomahawk connector. The Tomahawk bottom connector consists of a charging plug socket and a Tomahawk System connector (see figures that follow). The minimum configuration for the Tomahawk interface includes charging, mono audio, power out, ACI, and Fbus. The USB and stereo audio out are optional.

The Tomahawk system connector includes:

• Charging

Pads for 2 -wire charging in cradles

•Audio

• 2 -wire fully differential output audio

• 2-wire differential mic input

•Power out

• 2.78V 70 mA output to accessories

• Detection/controlling

•ACI

• Point to point bi-directional data line

•Fbus

• Standard Fbus

• AT command mode (Nokia Serial Bus)

• Phone message mode

• Fast Fbus, fast data bus to add on modules

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Metal shield

Plastic housing

9.50

Figure 4: Tomahawk system connector

Contacts (14 pieces)

Locking holes for accessories (2 pieces)

6.50

5.70

6.55

5.40

1.00

2.70

21.20

PWB

0.30

Metal shielding

ACI

Vout

Charge GND

Shielding GND

USB Vbus

USB D+ / Fbus RX

USB D- / Fbus TX

XMIC P

XMIC N

DATA GND

HSEAR P

HSEAR N

HSEAR R P

HSEAR R N

Figure 5: Mechanical dimensions and signals of Tomahawk bottom connectors

An accessory is detected by the ACI-line. All accessories will generate interrupt while inserted or removed from the phone’s Tomahawk system connector. Insertion of an accessory will generate HEADINT interrupt by pulling the ACI line down. Vout is enabled by the UPP. The MBUS line is connected to the HEADINT line. If the HEADINT interrupt from low to high transition occurs within 20msec, either a more advanced accessory is connected or a basic headset is connected.

3.50

Shielding GND

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Charger IF

The charger connection is implemented through the bottom connector. The DCT-4 bottom connector supports charging with both plug chargers and desktop stand chargers.

There are three signals for charging. The charger GND pin is used for both desktop and for plug chargers as well as the charger voltage. The PWM control line, which is needed for 3-wire chargers, is connected directly to the GND in the PWB so the 2112 engine does not provide any PWM control to chargers. Charge controlling is done inside the UEM by switching the UEM internal charger switch on/off.

The fuse (F100) protects from high currents (e.g., when broken or pirate chargers are used). The L100 protects the engine from RF noises that may occur in a charging cable. V100 protects the UEM ASIC from reverse-polarity charging and from high-charging voltage. The C106 is also used for ESD and EMC protection.

Test Interfaces

Production Test Pattern

The interface for 2112 production testing is a 5-pin pad layout in the BB area (see Figure 6). A production tester connects to these pads using spring connectors. The interface includes MBUS, USRX, FBUSTX, VPP, and GND signals. The pad size is 1.7mm. The same pads also are used for AS test equipment, such as a module jig and a service cable.

Figure 6: 5-pin layout in BB area

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Figure 7: Test points (bottom)

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Figure 8: Test points (top)

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General Information About Testing

Phone Operating Modes

The phone has three different modes for test/repair. Modes can be selected with suitable resistors connected to BSI lines as follows:

Table 12: Test/Repair Modes

Mode BSI Resistor Notes

Normal 75k

Local 3.3k

Test 6.8k Recommended with baseband testing. Similar to

Local mode, but making a phone call is possible.

The MCU software enters automatically to Local or Test mode at start-up if corresponding resistors are connected.

Note: The baseband does not wake up automatically when the battery voltage is connected (Normal Mode).

RF Module

Requirements

The 2112 supports CDMA 800 MHz as described in the following documents:

• IS2000-2-A Physical Layer Standard for CDMA2000 Spread Spectrum Systems

• IS-98D (Draft 4) Recommended Minimum Performance Standard for Spread

Antenna

An internal antenna is used.

Spectrum Mobile Stations

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Transmitter

Antenna

From

Baseband

BB I LPF

457.2MHz

VHF LO

÷2/÷4

IQ Modulator

0º

90º

IF VGA (IF AGC PDM)

UHF LO

0º

0º0º

90º

1052.61-107757MHz

Figure 9: RF transmitter block diagram

Upconverter

0º

0º0º

90º

RF VGA (RF AGC PDM)

TP1

Bandpass

Tx SAW

To Baseband

PWR Amplifier

TP2 TP3

Power

Detector

Isolator

TP4

Cell RX

Duplexer

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The transmit chain up to the RF driver stage is integrated into one transmit-integrated circuit (Jedi) with external power amplifiers (PA). The channel spacing is 30 kHz.

All data transmitted on the channel is convolutionally encoded and block-interleaved. Modulation is 64-ary orthogonal (RC1 and RC2) and the direct sequence is spread by a quadrature pair of PN sequences at a fixed chip rate. The data is filtered, O-QPSK modulated, and up-converted to the appropriate transmission frequency. RC3 and RC4 use HPSK modulation at data rates up to 153.6 kBPS (RC3) and 115.2 kBPS (RC4).

The baseband I/Q signals are converted to an IF frequency in the I/Q modulator by quadrature mixing. The modulated IF signals go through a variable gain amplifier (IF AGC) and then are routed to the Cell Tx path. The path consists of an upconverter and a variable gain RF amplifier. The IF signal is converted up to RF with a differential output upconverter and then fed to the RF amplifier. The RF amplifier has variable gain capability (RF AGC) with up to 40 dB of dynamic gain control.

The output of Jedi’s Cell RF amplifier is connected to an RF filter to reject TX noise in the RX band. The output of the RF filter goes to the PA, to an isolator, and finally to the antenna.

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Synthesizer

Figure 10 illustrates the synthesizers and how they interconnect in the system.

CELL:457.2MHz

JEDI

367.2MHz

VHF

counter

Yoda

19.2MHz

VCTCXO

19.2MHz to

19.2MHz to UPP

UPP

VHF

counter

UHF

counter

Figure 10: Synthesizer system block diagram

CELLl Band UHF VCO

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1st TX VHF LO Synthesizer (Jedi)

The TX VHF synthesizer is integrated within the Jedi RFIC and generates the LO signals for the IQ-modulator in Jedi. The synthesizer has an internal VCO with an external resonator. The VCO operates at two times the Cell IF frequencies. A band-switch signal (VCO_Band) is used to shift the center frequency of the external resonator.

The synthesizer is a dual-modulus prescaler and utilizes a phase detector with a charge pump that sinks or sources currents, depending on the phase difference between the detector input signals. The width of the pulses depends on the phase difference between the signals at input of the phase detector. The main divider, auxiliary divider, and reference divider are programmable through the serial interface to Jedi.

The TX VHF synthesizer generates 457.2MHz, and the comparison frequency is 30 kHz.

2nd RX VHF LO Synthesizer (Yoda)

The RX VHF synthesizer is integrated within the Yoda RFIC and generates the LO signals for the IQ demodulator in Yoda. The synthesizer has an internal VCO with an external resonator. The VCO operates at two times the common 183.6 MHz (367.2 MHz) RX IF frequency.

The synthesizer is a dual-modulus prescaler and utilizes a phase detector with a charge pump that signals or sources currents, depending upon the phase difference between the detector input signals. The width of the pulses depends on the phase difference between the signals at input of the phase detector. The main divider, auxiliary divider, and reference divider are programmable through the serial interface to Yoda.

The RX VHF synthesizer generates 367.2 MHz.

VCTCXO - System Reference Oscillator

The VCTCXO provides the frequency reference for all the synthesizers. It is a voltagecontrolled, temperature-compensated, 19.2MHz crystal oscillator that can be pulled over a small range of its output frequency. This allows for an AFC function to be implemented for any frequency accuracy requirements. This is done by DSP processing of received I/Q signals.

Closed loop AFC operation allows very close frequency tracking of the base station to be done in CDMA mode. This enables the unit to track out aging effects and gives the required center frequency accuracy in Cell band.

The most practical way of clock distribution is driving the two chips (Yoda and Jedi) directly from the VCTCXO. An internal buffer is used to drive the UPP in order to isolate the UPP’s digital noise from the VCTCXO, which prevents contamination of the 19.2 MHz reference onto the PLL chips of the system. Because the VCTCXO output is a sinewave, clock distribution does not cause any clock signal integrity problems, even for relatively long traces (which might occur in the case of a digital square waveform with fast transition times). The VCTCXO output is AC, coupled to Yoda, Jedi, and the digital ASICs.

2112 (RH-57)

System Module Nokia Customer Care

Receiver

LNA SW Control

I/Q Down

Converter

CDMA

BB Filter

Antenna

Duplexer

LNA

CELL SAW

Loop Filter

RFA

UHF VCO

1052.61-1077.57

UHF Synthsizer

JEDI

IFA

IF SAW

VCTCXO

VGA

CDMA

BB Filters

BB AMP

To BB

BB AMP

VHF PLL

367.2 MHz Bias and Control

Reference Clock

To Base-Band

AFC

Figure 11: Receiver block diagram

2112 (RH-57)

Nokia Customer Care System Module

The receiver is a dual conversion I/Q receiver with a first IF of 183.6 MHz. The front-end RFIC (Alfred) contains a low noise amplifier (LNA), a radio frequency amplifier (RFA), a down-converter, an intermediate frequency amplifier (IFA), and a local oscillator amplifier (LOA). Between the LNA and the RFA is a bandpass filter, which rejects out-ofband spurious and acts as image rejection. The IF filter is between the Alfred IC and the Yoda IC. The purpose of this filter is to guarantee rejection in adjacent and alternate channels.

The RX IF ASIC Yoda is used to convert the IF down to baseband I and Q. The ASIC contains a VGA section, an IQ demodulator, and baseband filters (BBFIL) for CDMA. Fix gain baseband amplifier (BBAMP), and RX VHF PLL. The I/Q BB signals are output to the UEM chip for analog-to-digital conversion and further signal processing.

2112 (RH-57) System Module Nokia Customer Care

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Nokia 2112, rh57 System Module

Specifications and Main Features

Frequently Asked Questions

User Manual

System Module

Contents Page

Introduction

Baseband Module

BB-RF Interface Connections

NOR Flash Memory and SRAM

User Interface Hardware

Keyboard

Power Key

Lights

Flashlight

Vibra

Audio Hardware

Earpiece

Microphone

MIDI Speaker

Audio Amplifier Interface

Battery

Battery Connector

Accessories Interface

System Connector

Charger IF

Test Interfaces

Production Test Pattern

General Information About Testing

Phone Operating Modes

RF Module

Requirements

Antenna

Transmitter

Synthesizer

Receiver