Analog Tristate Buffer

[coates]

Hi guys.

I'm trying to implement some sort of analog tristate buffer that can pass positive and negative DC signals so that I can force an analog input voltage to zero when necessary (to turn off a push-pull output).

Is this possible, in a simple way? Or would one have to add a bias voltage, then switch it, then remove the DC bias again?

Many thanks.

 

[FvM]

I understand a buffer amplifier followed by an analog switch as an analog tri-state buffer. It's e.g. utilized in sample-and-hold circuits. There are also OP-amps with disable feature. They set the output stage to high Z, but there's a certain leakage current, usually higher than with a true analog switch.