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Non-symmetrical Schmitt Trigger using OP-Amp with single power supply

A variation of the previous circuit is the single power supply op-amp Schmitt trigger circuit. This circuit does not require positive and negative voltage for the op-amp to operate. The negative voltage of the op-amp is connected directly to the ground (0V) of the circuit. This is the schematic drawing:

The calculation of the two threshold points is different. To calculate the High Threshold Level, you solve the following formula:

**R**_{TOT} = (R1 x R_{FB}) / (R1 + R_{FB})

**V**_{THRESHOLD_HIGH} = V * R2 / (R2 + R_{TOT})

For the Low Threshold Level, you solve the following formula:

**R**_{TOT} = (R2 x R_{FB}) / (R2 + R_{FB})

**V**_{THRESHOLD_HIGH} = V x R_{TOT} / (R1 + R_{TOT})

I have include a Non-Symmetrical Schmitt Trigger calculator using Op-Amp with single power supply in the Dr.Calculus page. Do not forget to visit and try it!