Hans Camenzind, Father of the NE555, Dies at the Age of 78
Walton Cocroft-esque voltage doubler using 555.
Annotated 1st page of the Fairchild datasheet (Signetics were the first manufacturer of the 555)
It took me a moment to sketch up the rough outline of a voltage regulator (down-buck) I build in 1986 at school. It relies on the really fast 555 chips' switching speed to saturate a bank of 4 parallel connected 2n3055s. I matched the 2n3055s to run in parallel for equal dissipation which took about a day to temperature test. (This involves wirring 4 transistors up in a test circuit and seeing which ones get hottest, keep those to one side. Repeat with some other transistors, until you have 4 with pretty similar gain characteristics for a set load.) They drive a choke in switched mode, and OK I used a zener and an LM741 as well in the enable circuit to turn the oscillator on and off when the output falls. I cannot remember what frequency I had the 555 at, sorry. It did have a 12Amp 12V transformer, and was able to provide really smooth regulation for 0-12v at up to about 5 amps. It would still control a 10Amp short circuiting load cleanly, so long as the switching noise was not a concern. This circuit was mounted in a Hamrads enclosure and was used in a school lab to charge lead-acid batteries, and even double as a battery on account it was able to run cool even under heavy loads provided by student abuse. The 4 2n3055's in a bank bank are never in the area between on and off for long, and thus they never dissipate much heat.
(Not my original diagram from 1986, I lost that)A note to anyone doing this at home, the output smoothing cap needs to be about 2000 uf, and you probably want a lot of small ones in parallel to make the value up, because they do get hot.