555 Timer Calculator
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Calculate frequency, period, duty cycle and HIGH/LOW times for the NE555 timer in astable configuration. Or calculate the pulse time in monostable mode.
Astable: oscillator
Monostable: timer
NE555 / LM555 / CMOS
Calculation
See also
Frequently asked questions
What is 555 astable mode?
Continuous oscillation. f = 1.44/((R1+2×R2)×C). Duty cycle = (R1+R2)/(R1+2×R2).
What is 555 monostable mode?
Single pulse of duration T = 1.1×R×C triggered by input. Used for delays and debounce.