I'm building this circuit:
I want the Schmidt trigger (first op amp) to begin by outputting +5V, creating a negative voltage ramp at the other op amp. When I power up the device, I have a 100R resistor in parallel with the capacitor so the ramp stays at 0V until I hit a switch.
My challenge: the Schmidt trigger will sometimes output +5V and sometimes -5V -- I need to make it only +5V on power-up.
I know it's stable in either direction and eventually switches when the voltage ramp goes high (or low) enough, but I need it to consistently output +5V every time I turn power on.
Please let me know if you have any suggestions. I've been wracking my brains for a solution.
I want the Schmidt trigger (first op amp) to begin by outputting +5V, creating a negative voltage ramp at the other op amp. When I power up the device, I have a 100R resistor in parallel with the capacitor so the ramp stays at 0V until I hit a switch.
My challenge: the Schmidt trigger will sometimes output +5V and sometimes -5V -- I need to make it only +5V on power-up.
I know it's stable in either direction and eventually switches when the voltage ramp goes high (or low) enough, but I need it to consistently output +5V every time I turn power on.
Please let me know if you have any suggestions. I've been wracking my brains for a solution.