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SAMSUNG Proprietary-Contents may change without notice
Circuit Description
2-9
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Power Amp
Power amplifier module(U403:ACPM-7813-DC1) amplifiers signal to be sent to the base station
through the antenna.
RF Band Pass Filter(Tx RF SAW Filter)
The RF BPF(F404) passes only specific frequency(836.49 ±12.5MHz) to send it to power
amp(U403:ACPM-7813-DC1).
Driver Amp
The driver amp(U402 ; It is included in S1M8690X) allows the signal to be inputted to the
power amp(U403) as a specified level.
Up-Converter(Mixer)
The up-converter(U402 ; It is also included in S1M8690X) receives the local signal
F
Tx
* 1.6666
and the signal controlled by TX AGC amp(in S1M8690X) to generate Tx RF signal
836.49±12.5MHz signal comes out from the mixer output by adding
F
Tx
* 1.6666
local signal.
F
Tx
means TX RF signal Frequency.
Automatic Gain Control Amp
The TX IF AGC amp in S1M8690X controls gain of AGC to deliver power level to be needed
at Driver amp. Its control voltage varies from 0.2V to 2.5V.