Schmidt Trigger Help: OP07 Comparator Circuit Design

[revird163]

I have been been trying to search forums and figure out the following question that I just cannot seem to get my head around!

Design a Schmidt comparator circuit based on an OP07 operational amplifier with the following characteristics: Power supply Voltages: +/- 12V Switching thresholds +1V, -1V

I have been trying to figure out the voltage saturation and then using this to find the resistor values for the schmidt trigger. I cannot work out what the voltage saturation is and how to calculate it at all.

Any help would be appreciated, I am really not the best at electronics!

The following is the circuit I am trying to use modeled on LTSpice:

 

[Jony130]

The saturation voltage can be found in op amp data sheet.
http://www.analog.com/media/en/technical-documentation/data-sheets/OP07.pdf (Output Voltage Swing).
Or you can use a resistor + two Zener diodes all in series at the op amp output and choose your own saturation voltage.

 

[gneill]

Consider that you have both +V and -V available since they're powering the op amp. You can tie the bottom of your R1 to -V rather than ground, and add another resistor of the same size as R1 to tie the + input to +V as well. Then tinker with your R2 value to adjust the total spread of the triggers. By symmetry the trigger points should lie on either side of the midpoint between +V and -V, or in other words, 0 V.

 

[berkeman]

I have been been trying to search forums and figure out the following question that I just cannot seem to get my head around!

Design a Schmidt comparator circuit based on an OP07 operational amplifier with the following characteristics: Power supply Voltages: +/- 12V Switching thresholds +1V, -1V

I have been trying to figure out the voltage saturation and then using this to find the resistor values for the schmidt trigger. I cannot work out what the voltage saturation is and how to calculate it at all.

Any help would be appreciated, I am really not the best at electronics!

The following is the circuit I am trying to use modeled on LTSpice:

Welcome to the PF.

I would make the power supply rails using two separate sources. Otherwise their relationship to ground can be ambiguous...