Hardware Description - Siemens SL 10 Service Manual

5.2 Hardware Description

The handset consists of five major integrated circuits. Some of them - beside others - are
integrated into just one single IC, the so called Multi Chip Module (MCM).
1) HiGOLD PMB 2800 (inside MCM)
This IC is a combination of microprocessor and signalprocessor.
The microprocessor is responsible for controlling the keyboard, SIM-Card, EEPROM, Flash
and RAM.
Furthermore it controls the power up/power down of the RF module and sets the amplification
of the PA.
The signal processor is responsible for processing the Rx I/Q signals (filtering, equalizing,
speech and channel decoding).
Furthermore it does the speech and channel encoding and the GSMK modulation of the Tx
I/Q signals.
3) GAIM PMB 2905 (inside MCM)
The GAIM provides the interface between the analogue signals (I/Q, voiceband, PA-control)
and its digital representation.
4) Receiver Circuit (PMB 2409)
This circuit provides the following main functionalities:
Low Noise Amplifier (LNA) with a fixed amplification of +20dB to amplify the
input RF signal.
Mixer to mix down the RF signal to the Intermediate Frequency (IF)
Programmable IF amplifier with a dynamic range of 60dB ( -10dB to +50dB in
steps of 2dB)
Mixer to mix down the IF signal to the baseband, generating and inphase (I) and a
quadrature (Q) signal.
Offset compensation for the I/Q signals.
5) Transmitter Circuit PMB 2240/45
This circuit provides the IF synthesizer, the I/Q modulator, prescalers to regulate the RF
synthesizer and a buffer stage to feed the PA.
Service Manual SL10
sm_sl10_lvl2_v11.doc
V1.1
Page 15 of 22
Private Communication Systems
Mobile Phones
PN MP ST
R. Fleuren
05/98