Siemens CF62 Service Manual

Company Confidential s Com

Service Repair Documentation

Level 2.5e - CF62, CF62R, CF63

Release Date Department Notes to change

1.0 27.04.2004 ICM MP CCQ GRM T New document

1.1 22.02.2005 COM MD CC GRM T CF62R added

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

Page

1 of 49

Release 1.1

Company Confidential s Com

Table of Contents:

1 List of available level 2,5e parts CF62, CF62R, CF63.....................................................3

2 Required Equipment for Level 2,5e.................................................................................5

3 Required Software for Level 2,5e CF62, CF62R, CF63 ..................................................5

4 Radio Part .......................................................................................................................6

5 Logic / Control...............................................................................................................20

6 Power Supply ................................................................................................................25

7 Interfaces.......................................................................................................................40

8 Acoustic.........................................................................................................................44

9 Display and Illumination.................................................................................................46

10 Keyboard.......................................................................................................................49

11 Magnetic switch.............................................................................................................49

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

Page

2 of 49

Release 1.1

Company Confidential s Com

1 List of available level 2,5e parts CF62, CF62R, CF63

Component Typ/Circuit Part Mobile Phone Component Details ID Partnumber

ASIC CF62, CF62R, CF63 Power Supply TWIGO03_LIGHT D361 L36145-J4682-Y54 Cap_Diode_26MHz_Circuit CF62, CF62R, CF63 Cap_Diode_1SV305 V3961 L36840-D61-D670 Capacitor RTC Buffer CF62, CF62R, CF63 Capacitor 100U C395 L36391-F1107-M Capacitor_PA_Buffer CF62, CF62R, CF63 Capacitor 4U7 C3998 L36197-F5008-F658 Capacitor_Transceiver_Circuit CF62, CF62R, CF63 Capacitor 100N C3920 L36853-C9104-M4 Capacitor_Transceiver_Circuit CF62, CF62R, CF63 Capacitor 100N C3931 L36853-C9104-M4 Capacitor_Transceiver_Circuit CF62, CF62R, CF63 Capacitor 100N C3932 L36853-C9104-M4 Capacitor_Transceiver_Circuit CF62, CF62R, CF63 Capacitor 100N C3966 L36853-C9104-M4 Capacitor_Transceiver_Circuit CF62, CF62R, CF63 Capacitor 100N C3999 L36853-C9104-M4 Capacitor_Transceiver_Circuit CF63 Capacitor 100N C3930 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 2U2 C368 L36377-F6225-M Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 2U2 C369 L36377-F6225-M Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 2U2 C370 L36377-F6225-M Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 4U7 C371 L36377-F6475-M Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 1U0 C372 L36377-F6105-K Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 2U2 C373 L36377-F6225-M Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C374 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 2U2 C377 L36377-F6225-M Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 2U2 C3973 L36377-F6225-M Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C165 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C200 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C201 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C202 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C207 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C209 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C220 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C362 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C363 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C364 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C365 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C366 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C367 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C381 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C382 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C383 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C384 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C385 L36853-C9104-M4 Capacitor_Twigo_Circuit CF62, CF62R, CF63 Capacitor 100N C1339 L36853-C9104-M4 Capacitor_Vreg_Circuit CF62, CF62R, CF63 Capacitor 4U 7 C1337 L36377-F6475-M Capacitor_Vreg_Circuit CF62, CF62R, CF63 Capacitor 4U 7 C1336 L36377-F6475-M Capacitor_Vreg_Circuit CF62, CF62R, CF63 Capacitor 4U 7 C1356 L36375-F3475-K

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

Page

3 of 49

Release 1.1

Company Confidential s Com

Coil_Vreg_Circuit CF62, CF62R, CF63 Coil 10U L1302 L36 151-F5103-M7 Coil_Vreg_Circuit CF62, CF62R, CF63 Coil 10U L1303 L36 140-F2100-Y6 Connector CF62, CF62R, CF63 Connector-RF - FOR RFTESTS X3800 L36334-Z97-C334 Diode KB7 CF62, CF62R, CF63 Diode_RB751S-40 V151 L36840-D5062-D670 Diode_Battery_Interface CF62, CF62R, CF63 Diode BAV99T V1400 L36840-D66-D670 Diode_SIM_Circuit CF62, CF62R, CF63 Diode ESDALC-6V1W5 V1605 L36197-F501 4-F98 Diode_Vreg_Circuit CF62, CF62R, CF63 Diode BAT760 V1303 L36840-D5076-D670 Filter_IO Interface CF62, CF62R, CF63 EMI_EMV_Filter Z1500 L36197-F5000-F116 IC MODUL PA CF62, CF62R, CF63 PF08140B SMD N3981 L36851-Z2002-A63

FEM HITACHI GSM900 1800

IC_FEM CF62, CF62R IC_FEM CF63

IC_Processor_EGOLD+ CF62, CF62R, CF63 PMB7850 V3.1F , V3.1H M42 D171 L36197-F5019-F415 IC_Transceiver CF62, CF62R, CF63 HD155155NPEB N3921 L36820-L6142-D670 Oszillator_RF_Logic CF62, CF62R, CF63 Oszillator_26MHz Z3961 L36145-F260-Y17 Oszillator_RTC CF62, CF62R, CF63 Oszillator_32,768KHZ Z171 L36145-F102-Y10 Resistor_Temp_TVCXO CF62, CF62R, CF63 Resistor_Temp 22k R R3967 L36120-F4223 - H Switch_CLAM CF62, CF62R, CF63 Magnetic Switch TLE4913 S3300 L36197-F5008-F63 Trans_Charge_Circuit CF62, CF62R, CF63 Transistor SI3911DV V361 L36830-C1110-D670 Trans_Keyboard_LED CF62, CF62R, CF63 Transistor SI1902DL/FDG6303N V2800 L36830-C1112-D670 Trans_LCD_LED CF62, CF62R, CF63 Transistor BC846S V2302 L36 840-C4014-D670 Trans_LCD_LED CF62, CF62R, CF63 Transistor BC846S V2303 L36 840-C4014-D670 Trans_Light_Circuit CF62, CF62R, CF63 Transistor SI1902DL V2210 L36830-C1132-D670 Trans_Light_Circuit CF62, CF62R, CF63 Transistor SI1902DL V2211 L36830-C1132 -D670 Trans_Light_Circuit CF62, CF62R, CF63 Transistor SI1902DL V2212 L36830-C1132 -D670 Trans_Light_Circuit CF62, CF62R, CF63 Transistor SI1902DL V2209 L36830-C1132 -D670 Trans_Vibra_Circuit CF62, CF62R, CF63 Transistor SI1865DL V211 L36810-C6 144-D670 Volt.Regulator_LCD_LED CF62, CF62R, CF63 VReg LM2733 N1304 L36820-C6250-D670

1900 FEM HITACHI GSM850 1800

1900

N3901 L36145-K280-Y258 N3901 L36145-K280-Y259

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

Page

4 of 49

Release 1.1

Company Confidential s Com

2 Required Equipment for Level 2,5e

- GSM-Tester (CMU200 or 4400S incl. Options)

- PC-incl. Monitor, Keyboard and Mouse

- Bootadapter 2000/2002 (L36880-N9241-A200)

- Adapter cable for Bootadapter due to new Lumberg connector (F30032-P226-A1)

- Troubleshooting Frame CF62 (F30032-P363-A1)

- Power Supply

- Spectrum Analyser

- Active RF-Probe incl. Power Supply

- Oscilloscope incl. Probe

- RF-Connector (N<>SMA(f))

- Power Supply Cables

- Dongle (F30032-P28-A1) if USB-Dongle is used a special driver for NT is required

- BGA Soldering equipment

Reference: Equipment recommendation Version X (Xwest version) (downloadable from the technical support page)

3 Required Software for Level 2,5e CF62, CF62R, CF63

- Winsui V1.45

- Software for GSM-Tester (GRT)

- Software for reference oscillator adjustment

- Internet unblocking solution (JPICS)

- Dongle driver for dongle protected Siemens software tools

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

Page

5 of 49

Release 1.1

Company Confidential s Com

4 Radio Part

The radio part realizes the conversion of the GMSK-HF-signals from the antenna to the base-band and vice versa.

In the receiving direction, the signals are split in the I- and Q-component and led to the D/Aconverter of the logic part. In the transmission direction, the GMSK-signal is generated in an Up Conversion Modulation Phase Locked Loop by modulation of the I- and Q-signals which were generated in the logic part. After that the signals are amplified in the power amplifier.

Transmitter and Receiver are never active at the same time. Simultaneous receiving in two bands is impossible. Simultaneous transmission in two bands is impossible, too. However the monitoring band (monitoring timeslot) in the TDMA-frame can be chosen independently of the receiving respectively the transmitting band (RX- and TX timeslot of the band).

The RF-part of the CF62/CF62R is dimensioned for triple band operation (EGSM900, GSM1800, GSM1900) supporting GPRS functionality up to multiclass 10. CF63 is dimensioned for trible band operation (GSM850, GSM 1800, GSM1900) supporting GPRS functionality up to multiclass 10.

The RF-circuit consists of the following components:

• Hitachi Bright VE chip set with the following functionality:

o PLL for local oscillator LO1 and LO2 and TxVCO o Integrated local oscillators LO1, LO2 (without loop filter) o Integrated TxVCO (without loop filter and core inductors for GSM) o Direct conversion receiver including LNA, DC-mixer, channel filtering and PGC-

amplifier

o Active part of 26 MHz reference oscillator

• Hitachi LTCC transmitter power amplifier with integrated power control circuitry

• Hitachi Frontend-Module including RX-/TX-switch and EGSM900 / GSM1800 / GSM

1900 receiver SAW-filters for CF62/CF62R

• Hitachi Frontend-Module including RX-/TX-switch and GSM850 / GSM 1900 receiver SAW-filters for CF63

Quartz and passive circuitry of the 26MHz VCXO reference oscillator.

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

Page

6 of 49

Release 1.1

Company Confidential s Com

4.1 Block diagram RF part

CF62 HIT RF Block Diagram

internal

antenna

matching

FEM

Hitachi

antenna

FEM incl.

SAW &

PIN-diode

switch

PA_RAMP

RF connector

only for

adjustment mechanical

switch

TXON_GSM RF_SW

TXONPA

BATT+

external

Loopfilter

Hitachi

"current sensing"

925-960 MHz

1805 - 1880 MHz

1930 - 1990 MHz

AFC_PNM

Internal power

control using

Vapc

Varicap

Crystal 26MHz

to Baseband

GSM LNA

PCN LNA

PCS LNA

integr. RF VCO

3476 - 3980

MHz

VCXO

26 MHz

26MHz

900

1800/1900 Integrated

TX-VCOs

frontend

IQ demodulator

RF PLL

TX-loop

filter

26MHz

DC autocalibration

integr.

IF VCO

640 - 656 MHz

external

1/2

loopfilter

1/2

IF PLL

PFD+CP

1/2

PFD+CP

1/2

PCN GSM

Analouge /

Digital Phase -

phase

charge

detector

pump

Transceiver IC

Hitachi Bright VE

frequency

detector

Feedback filter

GSM: 80MHz PCN: 80MHz DCS: 80MHz

IQ modulator

Vers.1.0 Confidential - Copyright Siemens AG

BATT+

VCC2_8

VCC_SYN

BANDSW

PA_RAMP

State

machine

Serial

Interface

TX_GSM TX_PCN TXONPA

RFCLK RFSTR RFDATA

26_MHz_BB

26_MHz_BT TVCXO

AFC_PNM

RF_I RF_IX

Basebend

RF_Q RF_QX

base bandradio part

CF63 HIT RF Block Diagram

internal

antenna

matching

FEM

Hitachi

antenna

FEM incl.

SAW &

PIN-diode

switch

PA_RAMP

RF connector

only for

adjustment

mechanical

switch

TXON_GSM RF_SW

TXONPA

BATT+

external

Loopfilter

Hitachi

"current sensing"

869 - 894 MHz

1805 - 1880 MHz

1930 - 1990 MHz

AFC_PNM

Internal power

control using

Vapc

Varicap

Crystal 26MHz

to Baseband

GSM LNA

PCN LNA

PCS LNA

integr. RF VCO

3476 - 3980

MHz

VCXO

26 MHz

26MHz

859

1800/1900 Integrated

TX-VCOs

frontend

IQ demodulator

RF PLL

26MHz

TX-loop

filter

1/2

PFD+CP

charge

pump

IF PLL

PFD+CP

1/2

PCN GSM

phase

detector

Transceiver IC

Hitachi Bright VE

26MHz

Analouge /

Digital Phase -

frequency

detector

Feedback filter

DC autocalibration

640 - 656 MHz

external loopfilter

GSM: 80MHz PCN: 80MHz DCS: 80MHz

integr.

IF VCO

1/2

Vers.1.0 Confidential - Copyright Siemens AG

IQ modulator

BATT+

VCC2_8

VCC_SYN

BANDSW

PA_RAMP

State

machine

Serial

Interface

TX_GSM TX_PCN TXONPA

RFCLK RFSTR RFDATA

26_MHz_BB

26_MHz_BT TVCXO

AFC_PNM

RF_I RF_IX

RF_Q RF_QX

Basebend

base bandradio part

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

Page

7 of 49

Release 1.1

Company Confidential s Com

4.2 Power Supply RF-Part

The voltage regulator for the RF-part is located inside the ASIC D361.(see chapter 5.2).It generates the required 2,8V “RF-Voltages” named VCC2_8 and VCC_SYN . The voltage regulator is activated as well as deactivated via SLEEPQ(VCC2_8)

(Miscellaneous R6) provided by the EGOLD+. The temporary deactivation is used to extend the stand by

time.

Circuit diagram

(TDMA-Timer H16) and VCXOEN_UC(VCC_SYN)

VCC2_8 VCC_SYN

4.3 Frequency generation

4.3.1 Synthesizer: The discrete VCXO (26MHz)

The CF62/62R,63 mobile is using a reference frequency of 26MHz. The generation of the 26MHz signal is done via a VCXO. This oscillator consists mainly of:

A 26MHz VCXO Z3961 A capacity diode V3961

TP (test point) of the 26MHz signal is the TP 3920

Page

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

8 of 49

Release 1.1

Company Confidential s Com

The oscillator output signal 26MHz_RF is directly connected to the BRIGHT IC (pin 35) to be used as reference frequency inside the Bright (PLL). The signal leaves the Bright IC as BB_SIN26M (pin

31) to be further used from the EGOLD+ (D171

(functional T3)).

Bright VE

VCXO Out

EGOLD In

To compensate frequency drifts (e.g. caused by temperature) the oscillator frequency is controlled by a (AFC) signal, generated through the internal EGOLD+ (D100 diode V3961. Reference for the “EGOLD-PLL” is the base station frequency received via the Frequency Correction Burst. To compensate a temperature caused frequency drift, the temperaturedepending resistor R3967 is placed near the VCXO to measure the temperature. The measurement result TVCXO is reported to the EGOLD+

(Analog Interface P3) via R138 as the signal TENV.

The required voltage VCC_SYN is provided by the ASCI D361

Waveform of the AFC_PNM signal from EGOLD+ to Oscillator

Signalform

EGOLD+

1 2 3

(functional U5)) PLL via the capacity

AFC

R158

30K 22K

C165

GND

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

AFC_PNM

100N

Page

R954

47K

9 of 49

C956

GND

100N

R953

C955

10N

GND

Release 1.1

Company Confidential s Com

4.3.2 Synthesizer: RFVCO(LO1)

The first local oscillator (LO1) consists of a PLL and VCO inside Bright (N3921) and an external loop filter The first local oscillator is needed to generate frequencies which enable the transceiver IC to demodulate the receiver signal and to perform the channel selection in the TX part. To do so, a control voltage for the LO1 is used, gained by a comparator. This control voltage is a result of the comparison of the divided LO1 and the 26MHz reference Signal. The division ratio of the dividers is programmed by the EGOLD+, according to the network channel requirements.

RF VCO

OUT

3476 - 3980

external

Loopfilter

Bright V

MHz

RF PLL

PFD

3 wire bus

from EGOLD

26MHz

Matrix to calculate the TX and RX frequencies CF62:

Band RX / TX Channels RF frequencies LO1 frequency IF freq.

EGSM 900 Receive: 0..124 935,0 - 959,8 MHz LO1 = 4*RF EGSM 900 Transmit: 0..124 890,0 - 914,8 MHz LO1 = 4*(RF+IF) 80,0 MHz

EGSM 900 Receive: 975..1023 925,2 - 934,8 MHz LO1 = 4*RF EGSM 900 Transmit: 975..1023 880,2 - 889,8 MHz LO1 = 4*(RF+IF) 82,0 MHz GSM 1800 Receive: 512..661 1805,2 - 1835,0 MHz LO1 = 2*RF GSM 1800 Transmit: 512..661 1710,2 - 1740,0 MHz LO1 = 2*(RF+IF) 80,0 MHz

GSM 1800 Receive: 661..885 1835,0 - 1879,8 MHz LO1 = 2*RF GSM 1800 Transmit: 661..885 1740,0 - 1784,8 MHz LO1 = 2*(RF+IF) 82,0 MHz

GSM 1900 Receive: 512..810 1930,2 - 1989,8 MHz LO1 = 2*RF GSM 1900 Transmit: 512..810 1850,2 - 1909,8 MHz LO1 = 2*(RF+IF) 80,0 MHz

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

Page

10 of 49

Release 1.1

Company Confidential s Com

Matrix to calculate the TX and RX frequencies CF63:

Band RX / TX Channels RF frequencies LO1 frequency IF freq.

GSM 850 Receive: 128..251 869,2 - 893,8 MHz LO1 = 4*RF GSM 850 Transmit: 128..251 824,2 - 848,8 MHz LO1 = 4*(RF+IF) 80,0 MHz

GSM 1900 Receive: 512..810 1930,2 - 1989,8 MHz LO1 = 2*RF GSM 1900 Transmit: 512..810 1850,2 - 1909,8 MHz LO1 = 2*(RF+IF) 80,0 MHz

The required voltage VCC_SYN is provided by the ASIC D361.

4.3.3 Synthesizer: IFVCO(LO2)

The second local oscillator (LO2) consists of a PLL and a VCO which are integrated in Bright and a second order loopfilter which is realized external (R3927; C3940; C3948). Due to the direct conversion receiver architecture, the LO2 is only used for transmit-operation. The LO2 covers a frequency range of at least 16 MHz (640MHz – 656MHz). Before the LO2-signal gets to the modulator it is divided by 8. So the resulting TX-IF frequencies are 80/82 MHz (dependent on the channel and band). The LO2 PLL and powerup of the VCO is controlled via the tree-wire-bus of Bright (EGOLD+ signals RFDATA;

RFCLK; RFSTR). To ensure the frequency stability, the 640MHz VCO signal is com pared

by the phase detector of the 2 signal passes the external loop filter and is used to control the 640/656MHz VCO.

The required voltage VCC_SYN is provided by the ASIC D361

PLL with the 26Mhz reference signal. The resulting control

640 - 656 MHz

external

Loopfilter

Bright V

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

IF PLL

Page

11 of 49

PFD

26MHz

IF VCO

OUT

3 wire bus

from EGOLD

Release 1.1

Company Confidential s Com

4.3.4 Synthesizer: PLL

The frequency-step is 400 kHz in GSM1800/GSM1900 mode and 800kHz in GSM850/EGSM900 mode due to the internal divider by two for GSM1800/GSM19000 and divider by four for GSM850/EGSM900. To achieve the required settling-time in GPRS operation, the PLL can operate in fastlock-mode a certain period after programming to ensure a fast settling. After this the loopfilter and currents are switched into normal-mode to get the necessary phasenoise-performance. The PLL is controlled via the tree-wire-bus of Bright.

4.4 Antenna switch (electrical/mechanical)

Internal/External <> Receiver/Transmitter The CF62/CF62R/CF63 mobile have two antenna switches. a) The mechanical antenna switch for the differentiation between the internal and

external antenna, which is used only RF adjustment.

b) The electrical antenna switch, for the differentiation between the receiving and

transmitting signals. To activate the correct settings of this diplexer, the EGOLD+ signals RF_SW and

TXON_GSM are required

CF62/CF62R, CF63 have an integrated “SAR detection” circuit. This circuit is used to decide if the internal antenna or an external antenna is used. The goal is, to reduce the transmit power when the internal antenna is used and the mobile is held very close to the body. On the other hand, the mobile can send with more power, if the external antenna is used. This distinction is done by the SAR detection circuit which consists of the voltage divider R872 and R873. The ANT_DET output provides a high level when the external antenna is used. ANT_DET

ntenna

to / from FEM

(Serial Interface L16) is connected to the EGOLD+

External Antenna (only for RF adjustment)

Internal antenna

to EGOLD

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

Page

12 of 49

Release 1.1

Company Confidential s Com

The electrical antenna switch CF62/CF62R

from PA

to Bright

The electrical antenna switch CF63

from PA

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

Page

to Bright

13 of 49

Release 1.1

Company Confidential s Com

N3901:

CF62,CF62R, CF63 Top View

CF62/CF62R Switching Matrix CF63 Switching Matrix

CF62/CF62R Pin assignment CF63 Pin assignment

Page

14 of 49

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

Release 1.1

Company Confidential s Com

4.5 Receiver

Receiver: Filter to Demodulator

The band filters are located inside the frontend module (N3901). The filters are centred to the band frequencies. The symmetrical filter output is matched to the LNA input of the Bright (N3921).The Bright VE incorporates three RF LNAs for GSM850/EGSM900, GSM1800 and GSM1900 operation. The LNA/mixer can be switched in High- and Low-mode to perform an amplification of ~ 20dB. For the “High Gain“ state the mixers are optimised to conversion gain and noise figure, in the “Low Gain“ state the mixers are optimised to large-signal behavior for operation at a high input level. The Bright performs a direct conversion mixers which are IQ-demodulators. For the demodulation of the received GSM signals the LO1 is required. The channel depending LO1 frequencies for 1800MHz/1900MHz bands are divided by 2 and by 4 for 850MHG/900MHz band. Furthermore the IC includes a programmable gain baseband amplifier PGA (90 dB range, 2dB steps) with automatic DCoffset calibration. LNA and PGA are controlled via EGOLD+ signals RFDATA; RFCLK;

RFSTR

baseband filter for both IQ chains. Only two capacitors which are part of the first passive RC-filters are external. The second and third filters are active filters and are fully integrated. The IQ receive signals are fed into the A/D converters in the EGAIM part of EGOLD+. The post-switched logic measures the level of the demodulated baseband signal and regulates the level to a defined value by varying the PGA amplification and switching the appropriate LNA gains.

From the antenna switch, up to the demodulator the received signal passes the following blocks to get the demodulated baseband signals for the EGOLD+:

Filter

N3901 Bright(N3921)

The required voltage VCC_SYN is provided by the ASIC D361

(RF Control J15, J16, J17). The channel-filtering is realized inside the chip with a three stage

LNA

Demodulator

PGC

Service Repair Documentation Level 2.5e - CF62, CF62R, CF63

Page

15 of 49

Release 1.1

+ 34 hidden pages