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Comparator Hystereses Calculator

See our other Electronics Calculators.

This calculator will compute the resistor ratio R1/R2 and reference voltage for given high and low threshold values for a hystereses curve, or the threshold values given the reference voltage and resistor ratio. 

The most commonly know comparator is the LM339 and it's various flavors. Rail to rail  op-amps can also be used as comparators.  The LMV324 is one such op-amp that is affordable, and works well as a comparator. 

The design equations for this calculator can be seen at: 

Comparator Hystereses Design Equations.


Input: (Note: Use minus sign "-" for negative voltages.)
Positive Supply Voltage: (V)
Negative Supply Voltage: (V)
Vth (High Threshold Voltage):
R2/R1 (Ratio of Resistors): 
Vtl (Low Threshold Voltage):
Vr (Reference Voltage): 

See our Votage Divider Calculator in order to compute R3 and R4 for a given Vr.


Comparator and Resistor Manufacturer Links

The best way to find comparators and resisters is to use our free Electronics Component Directory, where a myriad of electronics manufactures are listed.

Other Electronics Links

We offer a broad range of electrical engineering calculators and electronics articles and tutorials


Daycounter specializes in contract electronics design.  Do you need some help on your project?  Contact us to get a quote. 

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