RC delay after comparator or buffer?

[okw]

I use an opamp to determine if a sensor is above or below 2.5V. It has a lot more circuitry, I just trimmed it down for what's important. The sensor senses water level in a small tank, and the water can be a little bit wavy from time to time. So I added an RC delay on the output to relax the signal a bit. It helped, but is it better to place it after the buffer? (the buffer is there so the pump and valve controls does'nt disturb the opamp hysteresis).

[moffy]

It is kind of a '6 of one, half a dozen of another'(i.e. more or less the same) type of question, but I think I would prefer the filtering before the comparator.

[Benta]

Drop the gates and place a leaky integrator before the comparator.

[shapirus]

One thing to note is that the -02 gates don't have Schmitt trigger inputs, so they aren't designed for slow input signal level transitions. A -14, -17, -132, etc. gate will be a better choice.

Another problem is that LM358 is an op amp and not a comparator. I'm not sure if using it as a comparator will create any issues, though, but it's not supposed to be used like this.