Siemens C75 Service Repair Documentation page 27

Company Confidential
Copyright 2005© Siemens AG
7.1.2.8 USB Charging
The ASIC can support USB charging when USB charging is integrated in the charging
software. If charge voltage is in the range 4.4V to 5.25 V USB charging is ongoing. During
USB charging only limited charging is possible. Charge current is limited to 75, 150, 300 or
400 mA.
7.1.2.9 Audio multiplexer
The digital audio information from/to the DSP inside the
interface, the 26MHz from the RF part. The internal AD and DA converter are connected to
microphone and loudspeaker.
MONO1_OUT
MONO2_OUT
MONO1_IN
MONO2_IN
HP
SPK
MONO1_LP_OUT
MONO2_LP_OUT
STEREO1_OUT
PHANTOM_BUFF_OUT
STEREO1_OUT
Vibra
M
MICBIAS
HP
MICBIAS
MIC1
MIC2
HP
MIC
MICE1
MICE2
HP
MICE
I/O-Connector
I/O-Connector
Mono Headset
7.1.2.10 Interface
The ASIC has two serial control interfaces and one serial audio interface. With the serial
interfaces, all functions of the ASIC can be controlled. For time critical commands ( all audio
functions incl. Vibra) the SSC is used.
TWI interface
TWI ( two wire interface) is an I2C 2 wire interface with the signals Clock (I2C_CLK) data line
(I2C_DAT) and the interrupt (PM_INT).
Service Repair Documentation
Level 2.5e – C75
KEY-CLICK
&Ringing
...
DAC
MUX DAC
PWM DIV
DIV
MUX ADC
ADC
Mozart / Twigo 4
RINGIN RINGIN
I²C / TWI I²C / TWI
Control
SSC
SSC
I²S
I²S I²S_1
I²S_2
LINE1 EP1
LINE2
EP2
PLL
26MHz
MIC1
MIC2
I²S
I²S I²S_1
I²S_2
VMIC
SGold lite
BB & RF
Bluetooth
Page of
27 37
s Com
SGOLD are delivered via the I2S
Voice
Recording
MCU
NB
DAC
LP Filter
DSP
NB
MUX
ADC
Decoder
BB RF
GSM GSM
Encoder
Release 1.0