555 timer is one of the popular oscillator

What is an oscillator ?

Well, in electronic world oscillators is the heart of all digital circuits. You name it you will find it. like calculator, watches, remote control for TV or A/c, computer inverter anything.

Here i am going to write about the most popular oscillator build around 555 timer.

Following will allow you to calculate the frequency and duty cycle.

Astable 555 Square Wave Calculator

In an astable circuit, the output continually switches state between high and low without any intervention from the user. The duration of the high and low states are based on what values you choose for R1, R2 and C1.

The formulas used are:
Time High (secs) = 0.693 * (R1 + R2) * C1
Time Low (secs) = 0.693 * R2 * C1
Frequency = 1.44 / ((R1 + R2 + R2) * C1)
Duty Cycle Percentage = (Th / (Th + Tl)) * 100

Monostable 555 Timeout Calculator

This calculator is designed to give the timeout value (D) for a Monostable 555 Timer Circuit. When power is applied to a monostable circuit the output is low until the delay time has elapsed, the output then goes high and remains high.

The formula used is:
Time Out Delay (secs) = 1.1 * R1 * C1.