555 timer
Monostable pulse duration and classic astable period, frequency and duty cycle.
Inputs
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Results
- HIGH time
- 0.0138629436 s
- LOW time
- 0.00693147181 s
- Frequency
- 48.0898347 Hz
- Duty cycle
- 66.6666667 %
Equations apply to the classic circuit without a bypass diode. Check frequency limits, leakage and tolerances in the timer datasheet.
Formula & guidance
mono: t = ln(3)RC; astable: T = ln(2)(RA + 2RB)C
Equations apply to the classic circuit without a bypass diode. Check frequency limits, leakage and tolerances in the timer datasheet.
Change the example inputs and check each field’s units. Use equipment datasheets and applicable project standards for final decisions. Results do not establish Canadian electrical-code compliance or certify a design.