Whenever I use the 555 timer, it seems that the output polarity is invariably incorrect, and the way the 555 functions, it normally cannot generate a duty cycle of less than 50% — 90% yes, 10% NO!

The 555 timer is one of the most versatile integrated circuits available. It can generate PWM signals, tones, and single-shot pulses. You can even put one in a bi-stable mode similar to a flip flop.

Long and longer timeout periods are frequent goals for the ubiquitous 555 timer. Generally, this is accomplished (albeit unreliably) by unusually large electrolytic timing capacitors. However, here ...