Power Amplifier Module - LG T5100 Service Manual

2. TECHNICAL BRIEF
GSM900
Figure 5. Block Diagram of OPLL

2.4.3 Power Amplifier Module

The Power Amplifier Module [SKY77325, U709] is a dual-band GSM/DCS power amplifier module that
incorporates an indirect closed loop method of power control.
The indirect closed loop is fully self-contained and it does not require loop optimization. It can be
driven directly from the DAC output in the baseband circuit.
On-board power control provides over 37 dB of control range with an analog voltage input [VAPC].
Efficiency is about 53% at GSM and about 53% at DCS.
DCS OUT
DCS
GSM 900 IN
GSM 900 OUT
Figure 6. Internal Functional Block Diagram
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