Panasonic KX-TG3521BXB Service Manual page 27

4.9.1. 2.4GHz Mod/Demod Circuit (Base Unit RF Part)
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 2.4 GHz TX modulated signal is output from pin1. This TX signal is filtered by BPF (FL701) and supplied to
Antenna. 2.4 GHz RX signal from the Antenna is filtered by BPF (FL701) and supplied to pin 4 of IC701, then demodulated signal
(RX_DATA) comes out from pin 16. At the same time, RSSI (Received Signal Strength Indicator) outputs from pin 14. Reference
clock (13.824 MHz) from DSP block is supplied to pin 11 of IC701. V_PA and V_RF supply 2.5 V 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.
KX-TG3521BXB/KX-TG3521BXS/KX-TG3522BXB/KX-TG3522BXS/KX-TGA351BXB/KX-TGA351BXS
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