Siemens A75 Service Manual
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Copyright 2005© Siemens AG
Service Repair Documentation
Level 2.5e – A70, A75
Release Date Department Notes to change
1.0 06.06.2005 ICM MP CCQ GRM T New document
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Table of Contents:
1 Instruction 4
2 List of available level 2,5e parts A70 5
3 List of available level 2,5e parts A75 6
4 Required Equipment for Level 2,5e 8
5 Required Software for Level 2,5e 8
6 Radio Part 9
6.1 BLOCK DIAGRAM RF PART 10
6.2 POWER SUPPLY RF-PART 11
6.3 FREQUENCY GENERATION 11
6.4 RECEIVER 15
6.5 TRANSMITTER 16
6.6 BRIGHT IC OVERVIEW 17
6.7 ANTENNA SWITCH (ELECTRICAL/MECHANICAL) 19
7 Logic / Control 22
7.1 OVERVIEW OF HARDWARE STRUCTURE A70 22
7.2 OVERVIEW OF HARDWARE STRUCTURE A75 23
7.3 EGOLDLITE 24
7.4 SRAM 30
7.5 FLASH 30
7.6 SIM 30
7.7 VIBRATION MOTOR 30
7.8 DISPLAY MODULES 31
7.9 ILLUMINATION – KEYBOARD 33
8 Acoustic 34
9 Power Supply, Battery and Charging 34
9.1 POWER SUPPLY ASIC 35
9.2 BATTERY 42
9.3 CHARGING CONCEPT 43
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10 Interfaces 46
10.1 VIBRA (XG220) 46
10.2 EARPIECE (XG243) 47
10.3 MICROPHONE 48
10.4 BATTERY (X181) 48
10.5 IO CONNECTOR (X211) WITH ESD PROTECTION (Z211) 49
10.6 SIM 51
11 Keyboard 52
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1 Instruction
This Service Repair Documentation is intended to carry out repairs on Siemens repair level
2.5. The described failures shall be repaired in Siemens authorized local workshops only.
All repairs have to be carried out in an ESD protected environment and with ESD protected
equipment/tools. For all activities the international ESD regulations have to be considered.
Assembling/disassembling has to be done according to the latest A70, A75 Level 2 repair
documentation. It has to be ensured that every repaired mobile Phone is checked according
to the latest released General Test Instruction document (both documents are available in the
Technical Support section of the C-market).
Check at least weekly C-market for updates and consider all A70, A75 related Customer
Care Information, and Repair Information who are relevant for A70, A75.
A70 Partnumber on IMEI label: S30880-S2770-#xxx
A75 Partnumber on IMEI label: S30880-S2790-#xxx
, while # may be any letter (A-Z) and xxx may be any number from 100, 101, 102....
Scrap Handling: All Scrap information given in this manual are related to the
SCRAP-Rules and instructions.
Attention: Consider the new "LEAD-FREE" soldering rules (A70 and A75 affected)
(available in the communication market), avoid excessive heat.
If you have any questions regarding the repair procedures or technical questions spare not
hesitate to contact our technical support team in Kamp-Lintfort, Germany:
Tel.: +49 2842 95 4666
Fax: +49 2842 95 4302
e-mail: st-support@klf.siemens.de
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2 List of available level 2,5e parts A70
(according to Component Matrix V1.03 - check C-market for updates)
RF
Product
A70 HIT C204 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A70 HIT C230 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A70 HIT C368 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A70 HIT C369 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A70 HIT C370 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A70 HIT C371 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A70 HIT C372 L36377-F6105-K CAPACITOR 1U (Cap-Type6)
A70 HIT C373 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A70 HIT C377 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A70 HIT C916 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A70 HIT D171 L50610-L6150-D670 IC EGOLDLITE PMB7860
A70 HIT D361 L50645-J4682-Y55 IC ASIC SALZBURG75 TWIGO3+75
A70 HIT D901 L50651-Z2002-A82 IC MODUL PA PF0814 (PA-Type2)
A70 HIT D902 L50645-K280-Y303 IC FEM HITACHI GSM900 1800 1900 (Fem-Type5)
A70 HIT D903 L50620-L6170-D670 IC TRANCEIVER HD155165BP PB Free
A70 HIT N308 L50610-C6153-D670 IC V-REG 2.9V (Vr-Type2) PB Free
A70 HIT R106 L36852-C-X RESISTOR 0R0 (Res-Type8)
A70 HIT R141 L36852-C-X RESISTOR 0R0 (Res-Type8)
A70 HIT R201 L36852-C-X RESISTOR 0R0 (Res-Type8)
A70 HIT R204 L36852-C-X RESISTOR 0R0 (Res-Type8)
A70 HIT R205 L36852-C-X RESISTOR 0R0 (Res-Type8)
A70 HIT R221 L36852-C-X RESISTOR 0R0 (Res-Type8)
A70 HIT R222 L36852-C-X RESISTOR 0R0 (Res-Type8)
A70 HIT R295 L36852-C-X RESISTOR 0R0 (Res-Type8)
A70 HIT R371 L36852-C-X RESISTOR 0R0 (Res-Type8)
A70 HIT R805 L36852-C-X RESISTOR 0R0 (Res-Type8)
A70 HIT R902 L36852-C-X RESISTOR 0R0 (Res-Type8)
A70 HIT R955 L36120-F4223-H RESISTOR TEMP 22K (Res-Type7)
A70 HIT R958 L36852-C-X RESISTOR 0R0 (Res-Type8)
A70 HIT V151 L36840-D5062-D670 DIODE RB751S (Di-Type3)
A70 HIT V211 L36830-C1097-D670 TRANSISTOR FDG313N (Tra-Type1)
A70 HIT V222 L36830-C1112-D670 TRANSISTOR SI1902 (Tra-Type4)
A70 HIT V361 L36830-C1110-D670 TRANSISTOR SI3911 (Tra-Type3)
A70 HIT Z171 L50645-F102-Y40 QUARZ 32,768KHZ (Q-Type4)
A70 HIT Z211 L50640-U6034-D670 FILTER EMI (Fi-Type3) PB Free
A70 HIT Z950 L36145-F260-Y17 QUARZ 26MHZ (Q-Type4)
Chipset
ID Order Number Description CM
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3 List of available level 2,5e parts A75
(according to Component Matrix V1.03 - check C-market for updates)
RF
Product
A75 HIT C165 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C200 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C204 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A75 HIT C209 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C220 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C229 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C230 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A75 HIT C236 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C283 L36377-F6105-K CAPACITOR 1U (Cap-Type6)
A75 HIT C284 L36377-F6105-K CAPACITOR 1U (Cap-Type6)
A75 HIT C285 L36377-F6105-K CAPACITOR 1U (Cap-Type6)
A75 HIT C286 L36377-F6105-K CAPACITOR 1U (Cap-Type6)
A75 HIT C287 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A75 HIT C288 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A75 HIT C289 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A75 HIT C362 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C363 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C364 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C365 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C366 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C367 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C369 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A75 HIT C370 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A75 HIT C371 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A75 HIT C372 L36377-F6105-K CAPACITOR 1U (Cap-Type6)
A75 HIT C373 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A75 HIT C374 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C377 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A75 HIT C381 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C382 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C383 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C384 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C385 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C386 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C5 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C6 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
Chipset
ID Order Number Description CM
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A75 HIT C803 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C805 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C809 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C820 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C821 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C912 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C916 L36377-F6225-M CAPACITOR 2U2 (Cap-Type4)
A75 HIT C961 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT C965 L36853-C9104-M4 CAPACITOR 100N (Cap-Type2)
A75 HIT D171 L50610-L6150-D670 IC EGOLDLITE PMB7860
A75 HIT D361 L50645-J4682-Y55 IC ASIC SALZBURG75 TWIGO3+75
A75 HIT D901 L50651-Z2002-A82 IC MODUL PA PF0814 (PA-Type2)
A75 HIT D902 L50645-K280-Y303 IC FEM HITACHI GSM900 1800 1900 (Fem-Type5)
A75 HIT D903 L50620-L6170-D670 IC TRANCEIVER HD155165BP PB Free
A75 HIT N280 L50610-C6169-D670 IC V-REG LM2794TLX (Vr-Type5) PB Free
A75 HIT N307 L50610-C6232-D670 IC V-REG 1.8V (Vr-Type3)
A75 HIT N308 L50610-C6153-D670 IC V-REG 2.9V (Vr-Type2) PB Free
A75 HIT R106 L36852-C-X RESISTOR 0R0 (Res-Type8)
A75 HIT R141 L36852-C-X RESISTOR 0R0 (Res-Type8)
A75 HIT R205 L36852-C-X RESISTOR 0R0 (Res-Type8)
A75 HIT R221 L36852-C-X RESISTOR 0R0 (Res-Type8)
A75 HIT R222 L36852-C-X RESISTOR 0R0 (Res-Type8)
A75 HIT R295 L36852-C-X RESISTOR 0R0 (Res-Type8)
A75 HIT R371 L36852-C-X RESISTOR 0R0 (Res-Type8)
A75 HIT R805 L36852-C-X RESISTOR 0R0 (Res-Type8)
A75 HIT R902 L36852-C-X RESISTOR 0R0 (Res-Type8)
A75 HIT R910 L36852-C-X RESISTOR 0R0 (Res-Type8)
A75 HIT R955 L36120-F4223-H RESISTOR TEMP 22K (Res-Type7)
A75 HIT R958 L36852-C-X RESISTOR 0R0 (Res-Type8)
A75 HIT V151 L36840-D5062-D670 DIODE RB751S (Di-Type3)
A75 HIT V211 L36830-C1097-D670 TRANSISTOR FDG313N (Tra-Type1)
A75 HIT V222 L36830-C1112-D670 TRANSISTOR SI1902 (Tra-Type4)
A75 HIT V361 L36830-C1110-D670 TRANSISTOR SI3911 (Tra-Type3)
A75 HIT Z171 L50645-F102-Y40 QUARZ 32,768KHZ (Q-Type4)
A75 HIT Z211 L50640-U6034-D670 FILTER EMI (Fi-Type3) PB Free
A75 HIT Z950 L36145-F260-Y17 QUARZ 26MHZ (Q-Type4)
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4 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 A62/A65(A70/A75) (F30032-P405-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
- Soldering and BGA Soldering equipment for lead free soldering.
Reference: Equipment recommendation
(downloadable from the technical support page)
5 Required Software for Level 2,5e
- Windows XP
- X-Focus
- GRT Version 2 or higher
- Internet unblocking solution (JPICS)
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6 Radio Part
The radio part is realizes the conversion of the GMSK-HF-signals from the antenna to the
baseband 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 the
EGSM900 and GSM1800 band is impossible. Simultaneous transmission in the EGSM900
and GSM1800 band 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 is dimensioned for triple band operation (EGSM900, DCS1800, PCS19000)
supporting GPRS functionality up to multiclass 8.
The RF-circuit consists of the following components:
• Hitachi Bright VI E chip set (HD155165BP) with the following functionality:
o PLL for local oscillator LO1 and LO2 and TxVCO
o Integrated local oscillators LO1, LO2
o Integrated TxVCO
o Direct conversion receiver including LNA, DC-mixer, channel filtering and
PGC-amplifier
o 26 MHz reference oscillator
• Hitachi LTCC transmitter power amplifier with integrated power control circuitry
• Hitachi Frontend-Module including RX-/TX-switch and EGSM900 / DCS1800 / PCS
1900 receiver SAW-filters
• Quartz and passive circuitry of the 26MHz VCXO reference oscillator
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6.1 Block diagram RF part
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V
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6.2 Power Supply RF-Part
The voltage regulator for the RF-part is located inside the ASIC D361.It generates the
required 2,8V “RF-Voltages” named VDD_RF1 and VDD_RF2. VDD_RF2 is passed via a 0Ω
resistor and renamed as VDD_BRIGHT as operating voltage for the BRIGHT. The voltage
regulator is activated as well as deactivated via SLEEPQ
(M4)
provided by the EGOLDlite. The temporary deactivation is used to extend the stand by
time.
Circuit diagram
(TDMA-Timer R11) and VCXOEN_UC
VDD_RF1
DD_RF2
6.3 Frequency generation
Synthesizer: The discrete VCXO (26MHz)
The A70/A75 mobile is using a reference frequency of 26MHz. The generation of the 26MHz
signal is done via a VCO (Z950).
TP (test point) of the 26MHz signal is the TP 820
The oscillator output signal 26MHz_RF is directly connected to the BRIGHT IC
be used as reference frequency inside the Bright (PLL). The signal leaves the Bright IC as
RF_SIN26M
(ball G9) to be further used from the EGOLDlite (D171 (C8)).
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Bright 6E
To compensate frequency drifts (e.g. caused by temperature) the oscillator frequency is
controlled by the (RF_AFC) signal, generated through the internal EGOLDlite (D171
PLL. Reference for the “EGOLD-PLL” is the base station frequency received via the
Frequency Correction Burst.
The required voltage VDD_RF2 is provided by the ASCI D361
Waveform of the AFC_PNM signal from EGOLDlite to Oscillator
VCXO Out
EGOLD In
(A10))
Signalform
EGOLD+
1 2 3
1
RF_AFC
R1
AFC_PNM
C1
2
R2
C2
R3
3
C3
GND
GND
GND
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Synthesizer: LO1
First local oscillator (LO1) consists of a PLL and VCO inside Bright (D903) and an internal
loop filter
RF PLL
The frequency-step is 400 kHz in GSM1800 mode and 800kHz in EGSM900 mode due to the
internal divider by two for GSM1800 and divider by four for 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 VI E.
RFVCO (LO1)
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. The VCO
module is switched on with the signal PLLON. The full oscillation range is divided into 256
sub-bands 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 EGOLDlite, according to the
network channel requirements.
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Matrix to calculate the TX and RX frequencies A70/A75:
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
Synthesizer: LO2
The second local oscillator (LO2) consists of a PLL and VCO inside Bright (D903) and an
internal loop filter. 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 (EGOLDLite signals RF_DAT;
RF_CLK; RF_STR). To ensure the frequency stability, the 640MHz VCO signal is compared
by the phase detector of the 2
nd
PLL with the 26Mhz reference signal. The resulting control
signal passes the external loop filter and is used to control the 640/656MHz VCO.
The required voltage VDD_BRIGHT is provided by the ASIC D361
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6.4 Receiver
Receiver: Filter to Demodulator
The band filters are located inside the frontend module (D902). The filters are centred to the
band frequencies. The symmetrical filter output is matched to the LNA input of the Bright .The
Bright 6E 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 IQdemodulators. 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 DC-offset calibration. LNA and PGA
are controlled via EGOLDlite signals RF_DAT; RF_CLK; RF_STR
channel-filtering is realized inside the chip with a three stage 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 EGOLDlite. 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 EGOLDlite:
Filter
LNA
Demodulator
PGC
D903 Bright(D903)
The required voltage VDD_BRIGHT is provided by the ASIC D361
(RF Contr N6, R6, N4). The
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6.5 Transmitter
Transmitter: Modulator and Up-conversion Loop
The generation of the GMSK-modulated signal in Bright (D903) is based on the principle of
up conversion modulation phase locked loop. The incoming IQ-signals from the baseband
are mixed with the divided LO2-signal. The modulator is followed by a lowpass filter (corner
frequency ~80 MHz) which is necessary to attenuate RF harmonics generated by the
modulator. A similar filter is used in the feedback-path of the down conversion mixer.
With help of an offset PLL the IF-signal becomes the modulated signal at the final transmit
frequency. Therefore the GMSK modulated rf-signal at the output of the TX-VCOs is mixed
with the divided LO1-signal to a IF-signal and sent to the phase detector. The I/Q modulated
signal with a center frequency of the intermediate frequency is send to the phase detector as
well.
The output signal of the phase detector controls the TxVCO and is processed by a loop filter
whose components are external to the Bright. The TxVCO which is realized inside the Bright
chip generates the GSMK modulated frequency.
Modulator
Bright(D903)
The required voltage VDD_BRIGHT is provided by the ASIC D361
Filter
PD
TxVCO
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