Learn more with dummies

Enter your email to join our mailing list for FREE content right to your inbox. Easy!

Using Popular Timer ICs: 555 and 556 Pinouts

By Dickon Ross, Doug Lowe

Part of Electronics All-in-One For Dummies Cheat Sheet (UK Edition)

The 555 is one of the most popular integrated circuits (ICs) ever made. When you use it, you need to be aware of the purpose of each of the eight pins in the 555 package. You may also occasionally use a 556 IC, which consists of two 555 timers in a single package, and the same applies to knowing its pinouts as well.

Function 555 Timer 556 First Timer 556 Second Timer
Ground 1 7 7
Trigger 2 6 8
Output 3 5 9
Reset 4 4 10
Control voltage 5 3 11
Threshold 6 2 12
Discharge 7 1 13
Vcc 8 14 14