Ghz Pa (Power Amplifier) Circuit; Ghz Lna (Low Noise Amplifier) Circuit - Panasonic KX-TG6500BXB Service Manual

KX-TG6500BXB / KX-TGA650BXB

21.4. 5.8GHz PA (Power Amplifier) Circuit

This block amplifies power of 5.8GHz TX signal.
5.8GHz TX signal from 5.8GHz Converter circuit is filtered by 5.8GHz-BPF FL811, and amplified by Power amplifier IC851, and
then passes through 5.8GHz-BPF FL861. After that, it is supplied to Antenna Switch circuit.
V_PA is approximately 4.0V at Base Unit, and 3.3V at Handset.
Q855 is switched by PA_CONT signal, and supplies Gates voltage of Power Amplifier IC851.

21.5. 5.8GHz LNA (Low Noise Amplifier) Circuit

This block amplifies receiving 5.8GHz signal.
5.8GHz RX signal from Antenna Switch circuit amplified by LNA (Low Noise Amplifier) Q871 and filtered by HPF (L822-L825), and
then supplied to 5.8GHz Converter circuit.
Q875 is switched by RX_EN signal, and supplies VCC_5.8G (regulated 3.0V) to LNA Q871.
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