Dumb question about Track and Hold, Sample and Hold Units

[Neil Parfitt]

Hi Brian,

I feel like i'm missing something really obvious -  i cant seem to see a difference in their behaviours when triggering them... they both appear to sample the input and just hold it.

What's the difference between these two?

Neil

[Brian@O|D]

The difference becomes apparent when you use gates.  A track-and-hold will track the input (i.e. output = input) while the gate is high and hold the output constant when the gate goes low.  The sample-and-hold samples and holds the signal on a rising edge.