LG G7100 Service Manual page 30

3. TECHNICAL BRIEF
A. BB Transmit section
This section generates in-phase and quadrature BB modulated GMSK signals (BT = 0.3) in
accordance with GSM 05.05 Phase 2 specifications.
The transmit channel consists of a digital GMSK modulator, a matched pair of 10-bit DACs and a
matched pair of reconstruction filter.
B. BB Receive section
This section consists of two identical ADC channels that process baseband in-phase(I) and
quadrature(Q) input signals.
Each channel consists of a coarse switched capacitor input filter, followed by a high-order sigma-
delta modulator and a lowpass digital filter.
C. Auxiliary section
This section contains two auxiliary DACs(AFC DAC, IDAC) for system control.
This section also contains AUX ADC and Voltage Reference
AUX ADC : 6 channel 10 bits
AFC DAC : 13 bits
IDAC : 10 bits
D. Voiceband section
Receive audio signal from MIC. The phones use differential configuration.
Send audio signal to Receiver. The phones use differential configuration.
It interconnects external devices such as main microphone, main receiver, ear-phone and Hands
free kit through the VINNORP, VINNORN, VOUTNORP, VOUTNORN, VINAUXP, VINAUXN,
VOUTAUXP, VOUTAUXN
VINNORP, VINNORN: Main MIC positive/negative terminal.
VOUTNORP, VOUTNORN: Main Receiver positive/negative terminal.
VINAUXP, VINAUXN: Hands free kit microphone positive/negative terminal.
VOUTAUXP, VOUTAUXON: Hands free kit speaker positive/negative terminal.
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