User Guide

Pin number,
connector X1000
Destination Test point Name of the
line/signal
NOTES
39
Camera, X1470
J1024 Serial Data CCI I2C
HWA, D1470
46 LED driver, D1300 J1011 PWM300
Back-up battery interface connections and electrical characteristics
Table 19 Back-up battery connections
Pin name I/O Connection Notes
VBack -> N2200,
VBack
Table 20 Back-up battery electrical characteristics
Description Parameter Min Typ Max Unit
Back-Up
Battery
Voltage
Vback 0 2.5 2.7 V
RF description
Introduction to receiver functionality
Receiver functions are implemented in RF ASIC N7505.
The receiver is a linear direct conversion receiver consisting of separate front ends (LNA (Low Noise Amplifier)
and demodulator) for each supported system. After the demodulators, the signal paths are combined to one
common BB path.
GSM receiver
As GSM850, GSM900, GSM1800, GSM1900 Rx branches are functionally identical, the following description is
applicable to all of them.
The received signal goes from the GSM antenna to the front end module (FEM) which includes switches from
band selection. FEM is followed by dedicated SAW filters which are dual packaged so that one holds SAWs for
850 and 900 and the other for 1800 and 1900 bands. The SAW filters are followed by integrated LNAs residing
in N7505.
The LNAs are followed by demodulators which downconvert the signal to baseband I and Q signals.
The channel select filter is set to 115 kHz in the GSM mode.
Introduction to transmitter functionality
Transmitter functions are implemented in the RF ASIC N7505. The ASIC contains a BB frequency low pass filter,
which is tunable according to the signal bandwidth of the system in use.
RM-198
Nokia Customer Care System Module
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