Calculate timing component values for a monostable timer pulse.
The monostable pulse width depends only on R and C, not on supply voltage, because the threshold is a fixed fraction of supply. The 1.1 factor comes from the natural logarithm of 3. Retriggering before the pulse ends produces unpredictable timing, so the maximum trigger rate must leave margin beyond the pulse width.
Timer IC
t = 1.1 R C for a monostable timer
t = 1.1 R C for a monostable timer The monostable pulse width depends only on R and C, not on supply voltage, because the threshold is a fixed fraction of supply. The 1.1 factor comes from the natural logarithm of 3.
Retriggering before the pulse ends produces unpredictable timing, so the maximum trigger rate must leave margin beyond the pulse width.
This calculator takes 3 inputs: Timing resistance, Timing capacitance, Target pulse width. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.