I'm using an ADRF6801 demodulator in combination with an ADRF6701 modulator.
I want to monitor junction temperatures of both chips, so the chips were configured to use the VPTAT temperature proportional voltage output at the MUXOUT pin.
This is working properly if both chips are using their internal PLL.
But when I let e.g. ADRF6701 be the "LO generator" for the ADRF6801 (or vice versa), then only the active chip (="LO generator") does output the VPTAT voltage. The other one keeps the pin at GND (0V).
I did not find any information about such a behaviour in the datasheet. Is this behaviour intended?