The 555 timer is one of the most used and useful ICs ever produced. Designed in 1971 by Hans Camenzind it provides a way to include different methods of timing and oscillation into your circuits.

In the time delay mode the time is precisely controlled by one external resistor and capacitor. In oscillator mode the frequency and duty cycle are controlled with two external resistors and one capacitor.

• Ideal for use in 5V circuits
• Multiple modes:
• Astable: square wave of configurable frequency
• Monostable: pulse of configurable duration on trigger
• Bistable: output dependant on two input states
• Inverting buffer: output is opposite of input
• Can be used with breadboard and perfboard easily

Available in both a single (555) and dual (556) package. The dual package contains two 555 timers which share common ground and source pins.

Update: as of 9th April 2018 we have moved to a different version of the 555 Timer, you can find the datasheet for the previous (discontinued) version here

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