Ghz Mod/Demod Circuit - Panasonic KX-TG5621BXS Service Manual

KX-TG5621BXS / KX-TGA561BXS

15.2. 2.4GHz Mod/Demod Circuit

IC701 incorporates all of the modulation and demodulation functions. TX Digital data (TX_DATA) from DSP is supplied to pin 27
of IC701, and then 2.4GHz TX modulated signal is output from pin1. This TX signal goes into the 5.8GHz Converter circuit. 2.4GHz
RX signal from 5.8GHz Converter circuit is passed through matching circuit and supplied to pin4 of IC701, then demodulated signal
(RX_DATA) comes out from pin 16. At the same time, RSSI (Received Signal Strength Indicator) outputs from the pin 14.
Reference clock (13.824MHz) from DSP block is supplied to pin 11 of IC701. VCC_2.4G supplies 2.5V regulated voltage.
Note:
The exposed GND-PLATE on the bottom of the IC701 supplies the circuit ground(s) for the entire chip. It is very important that
a good solder connection is made between this GND-PLATE and the ground plane of the PCB underlying the IC701.
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