Calculate frequency, pulse width and duty cycle, or find timing resistors.
The simulator models the 555 latch, reset, discharge and thresholds at one-third and two-thirds of VCC. Use 4.5–16 V. Output losses and real-component tolerances are simplified. The first astable pulse is longer; for a monostable pulse, press and release the trigger button briefly.
How to use
- Choose astable oscillation or a monostable pulse.
- Enter resistors and capacitance, or specify a target frequency in hertz or pulse duration in seconds.
- Open the simulator, probe V1 and C1, and briefly press K1 for a monostable pulse.
Circuit model
tH = ln(2) × (R1 + R2) × C; tL = ln(2) × R2 × C; f = 1/(tH + tL); D = tH/(tH + tL); tmono = ln(3) × R1 × C.