If you’ve had the opportunity to do some basic circuit design, before all the microcontroller platforms like the Arduino became popular, you would have worked with a chip called the 555.

Originally designed in 1971 the 555, lovingly referred to as the “triple nickel” is a small, inexpensive, and extremely flexible analog/digital hybrid chip used for timers, oscillators, pulse generation, delays, and control circuits. Its internal design, 23 transistors, 16 resistors, and 2 diodes, made it simple, robust, and easy to integrate into countless designs.

Currently the CMOS version of the 555 is used in battery protection circuits, motion detectors, LED flashers, and many other applications. It is a cheap, robust, timer with a proved track record of durability.

While the design did not actually begin or end on May 5th, I think it is only appropriate to celebrate the 55th anniversary of the 555 on 5/5.