I'm working on using the ADG707A Multiplexer with the AD595 Thermocouple amplifier to build a thermocouple multiplexer. I am basing it off of the thermocouple multiplexer in the application notes (AN-369). I notice that you suggest permanently enabling the multiplexer with a +5V input to prevent the AD595 from being left floating.
From what I can tell in the data sheet, the enable pin is limited to VDD+2V and 20mA. Does this mean it would be okay to use VDD(+12V) with a current limiting resister to hold the enable pin high?
We are using +/-12V input rails to power the ICs and it would be really nifty to use +12V rail to hold enable the multiplexer instead of creating a +5V supply just for the enable pin.