Dual Band Gsm Power Amplifier - LG U8210 Service Manual

3. TECHNICAL BRIEF
LMV225
20076001
Figure 3.5.5-1 Block diagram of LMV225TLX with high resistive tap
Figure 3.5.5-2 Power detector response, Vout vs PA output power
3.5.6 Dual band GSM power amplifier (U209 : SKY77328)
The SKY77328 Power Amplifier Module (PAM) is designed in a low profile (1.2 mm), compact form
factor for quad-band cellular handsets comprising GSM850/900, DCS1800, and PCS1900 operation.
The PAM also supports Class 12 General Packet Radio Service (GPRS) multi-slot operation.
The module consists of separate GSM850/900 PA and DCS1800/PCS1900 PA blocks, impedance-
matching circuitry for 50 Ω input and output impedances, and a Power Amplifier Control (PAC) block
with an internal current-sense resistor. The custom BiCMOS integrated circuit provides the internal
PAC function and interface circuitry.
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