LG B2070 Service Manual page 31

3. TECHNICAL BRIEF
3.6.1 Baseband Transmit Section
1. The AD6537B Baseband Transmit Section is designed to support GMSK for both
single-slotand multi-slot application.
2. The transmit channel consists of a digital GMSK modulator, a matched pair of 10-bit DACs
and a matched pair of reconstruction filter.
AD6537B
BSIFS
Baseband
BSDI
Serial
Port
CSFS
Control
CSDI
Serial
CSDO Port
3.6.2 Baseband Transmit Section
1. This section consists of two identical ADC channels that process baseband in-phase(I) and
quadrature(Q) input signals.
AD6537B
BSOFS
Baseband
BSDO
Serial
Port
GMSK
Modulator
Ramp
RAM
Figure 3-12 AD6537B BASEBAND TRANSMIT SECTION
Digital
Filter
Digital
Filter
Figure 3-13 AD6537B BASEBAND RECEIVER SECTION
SC
Tx
Filter
DAC
SC
Tx
Filter
DAC
Ramp SC
DAC Filter
Rx SC
ADC Filter
Rx SC
ADC Filter
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PGA
Active
CT Filter
PGA
Active
CT Filter
PGA
Active
CT Filter
Othello
IP
IN
QP
QN
IP
IN
QP
QN
PA