C903
1228-1147 rev. 1
FUNCTIONAL OVERVIEW
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Technical Description
Resistance Identification and Temperature Measurement
The resistance identification mode utilizes the constant current source to feed the battery
data output while monitoring the voltage at the battery data node with general purpose
ADC the conversion is started through I2C.
Resistance Identification (A) and Temperature Measurement (B):
SIM Interface
The SIM interface supplies level is shifting between the digital baseband controller and the
SIM/USIM card. Moreover, hard-wired SIM deactivation functionality manages removal of
a SIM card that has not been powered down.
Block Diagram of the SIM Interface:
CODEC Overview
The CODEC is encoding analog audio signals and analog voice signals into digital signals
using Analog to Digital converters (ADCs). This is done in the coder section of the CODEC,
also named the TX path (transfer section). The CODEC is also decoding digital audio
signals and digital voice signals into analog signals using DACs. This is done in the
decoder section of the CODEC, also named the RX path (receiver section).
CODEC Block Schematic:
SEMC Troubleshooting Manual
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(129)
