555 Timer Frequency & Pulse
Estimate the timing of a repeating pulse or a single-shot delay.
Input parameters
Results
Check the timer variant, tolerances, and output load.
Model & assumptions
Astable: tH = ln(2)(RA + RB)C; tL = ln(2)RB C; f = 1/(tH + tL). Monostable: t = ln(3)RC.
Ideal threshold model. Component tolerances, leakage and the chosen timer variant limit actual timing.
Sources
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