Panasonic KX-TG6071BXM, Service Manual

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KX-TG6071BXM/KX-TGA601BXM
4.9.2. 5.8 GHz Mod/Demod Circuit
IC701 incorporates all of the modulation and demodulation functions.
TX Digital data (TX_DATA) from DSP is supplied to pin 17 of IC701, and then 5.8 GHz TX modulated signals is output from pin 1.
This 5.8 GHz TX signal goes into the PA circuit in IC801.
On the other hand, amplified 5.8 GHz RX signal from LNA in IC801 is passed through BALUN (BALunce-UNbalunce) matching cir-
cuit and supplied to pin 7 and pin 8.
In IC701, RX signal is down-converted to 432 kHz IF signal, and demodulated, and RX digital data (RX_DATA) goes from pin 17 to
DSP.
IC701 outputs some digital signals (PAEN, ANTSEL_A, ANTSEL_B, LNAEN, RXGAIN), and controls IC801.
Reference Clock signal (13.824 MHz) is supplied to pin 25.
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.