Perhaps someone has already made this measurement.
I am going to be doing something a bit odd with a PIC. I will configure a pin as an output and set it low most of the time. From time to time, I will switch it into the high impedance input state, wait a little while while a capacitor gets charged and then trip the ADC to measure the voltage.
Doing this saves me an analog switch. I am a bit concerned about the charge that gets injected as the port is reconfigured. Does anyone have a number for this? Will it vary with temperature?
Wild guesses welcome.