- Wed Apr 10, 2013 1:43 pm
#158183
I have a Schmidt trigger as follows:
(Note that power supplies *are* decoupled near the pins)
The issue is that I want OUT to be 5V upon power-up. I then adjust RV1 until I get 2V in the input. This tends to be around 6.67K (to save everyone the math).
Unfortunately, upon power-up, OUT often remains at -5V. I say often because *sometimes* it will switch to the positive value I want.
The "input" for the Schmidt trigger comes from a different op amp, whose output should be zero (virtual ground), represented by GND in the photo above.
Can anyone offer some insight as to what I'm missing?
(Note that power supplies *are* decoupled near the pins)
The issue is that I want OUT to be 5V upon power-up. I then adjust RV1 until I get 2V in the input. This tends to be around 6.67K (to save everyone the math).
Unfortunately, upon power-up, OUT often remains at -5V. I say often because *sometimes* it will switch to the positive value I want.
The "input" for the Schmidt trigger comes from a different op amp, whose output should be zero (virtual ground), represented by GND in the photo above.
Can anyone offer some insight as to what I'm missing?