NE555 Timer Calculator
Calculate frequency, duty cycle, and pulse duration for 555 timer circuits in astable or monostable mode.
⚙️ Configuration
📊 Results
Frequency:
Duty Cycle:
Time High (tH):
Time Low (tL):
Pulse Duration (T):
📈 Output Waveform
Theory & Formulas
Astable Mode
In astable mode, the NE555 acts as a free-running oscillator, generating a continuous square wave without any external trigger. The frequency and duty cycle are determined by two resistors (R1, R2) and one capacitor (C).
- Time High (tH):
0.693 * (R1 + R2) * C - Time Low (tL):
0.693 * R2 * C - Frequency (f):
1.44 / ((R1 + 2*R2) * C) - Duty Cycle (%):
(tH / (tH + tL)) * 100
Monostable Mode
In monostable mode, the NE555 generates a single output pulse of a specific duration (T) when a trigger signal is applied. This duration is set by one resistor (R) and one capacitor (C).
- Pulse Duration (T):
1.1 * R * C
