Astable & Monostable Multivibrator Formula & Calculator

This calculator determines the frequency and pulse width of astable and monostable multivibrators using the following formulas:

Astable Multivibrator:

• Frequency (f) = 1.44 / ((RA + 2RB) * C)
• Time High (TH) = 0.693 * (RA + RB) * C
• Time Low (TL) = 0.693 * RB * C

For Monostable Multivibrator:

• Pulse Width (T) = 1.1 * R * C
• Frequency (f) = 1 / T

Where:

• RA and RB are the resistances in ohms (Ω) for the astable mult ivibrator
• R is the resistance in ohms (Ω) for the monostable multivibrator
• C is the capacitance in farads (F) for both multivibrators

Astable Multivibrator Calculator

Example Calculation: Let’s say we have an astable multivibrator with the following values:

Inputs:

• RA = 10 kΩ
• RB = 20 kΩ
• C = 0.01 μF (which is 10 x 10^-6 F)

Outputs:

• Frequency (f) = 2.88 Hz
• Time High (TH) = 0.2079 seconds
• Time Low (TL) = 0.1386 seconds

This means that the astable multivibrator will oscillate at a frequency of approximately 2.88 Hz, with a high time of 0.2079 seconds and a low time of 0.1386 seconds based on the given values for RA, RB, and C.

Monostable Multivibrator Calculator

Now, let’s say we have a monostable multivibrator with the following values:

Inputs:

• R = 50 kΩ
• C = 10 μF (which is 10 x 10^-6 F)

Outputs:

• Pulse width (T) = 0.55 seconds
• Frequency (f) = 1.82 Hz

This means that the monostable multivibrator will produce a pulse width of 0.55 seconds and a frequency of approximately 1.82 Hz based on the given values for R and C.