555 bistable multivibrator 2012-08-29

The most common 555 configurations are that of a Astable and Monostable Multivibrator. This shows how a 555 may be used as a Bistable Multivibrator. While a 555 has a Set/Reset flip flop built in (another type of Bistable Multivibrator) this circuit uses the concept of hysteresis to accomplish the same thing.

If you use the red wire shown on the illustration as a toggle the LEDs will flip states, and stay that way until the circuit is toggled again. It will work over the entire power supply...

Click to expand...

ckt-boarder said:

Thanks for explaining the theory behind the bistable operation. Going along with what you've said, most of the schematics I've come across have used the astable or monostable configs, so it's great to have some background on this one.

Click to expand...