🚀 go-pugleaf

Thanks for all of the suggestions that I've received for the 12V to 5V
conversion in a car.  

What I've done is replace the 7805H (220 package) regulators with
7805KC (TO3 package) regulators to drive the logic circuitry.  The
logic draws relatively little current (each regulator needs to push
about 150 mA) and the pair of regulators are probably actually
overkill for this.  To drive the current-hogging LEDs, I've used a
LM323K (TO3 package) with a 3" x 5" finned heat sink.  In this way,
separate regulators drive the logic and the LEDs, so any power
cycling that may occur due to the LEDs making the regulator too hot
affects only the LEDs (a momentary loss of power to the LEDs doesn't
hurt anything, whereas a momentary loss of power to the registers,
etc, would lose the state information.)

What I've done is basically the "simple" fix -- better, more robust
suggestions were given, but I wanted to use the parts that I could
find at local second-hand electronics stores and flea markets.

I'd like to thank everybody that gave suggestions, especially:

Tom Bruhns (tomb@hplsla.hp.com)
Jeff DePolo (depolo@eniac.seas.upenn.edu)
Mark Hoy (mark@retix.retix.com)
Cary Logan (logan@titan.tsd.arlut.utexas.edu)
Stephen MacMinn (macminn@powertool.crd.ge.com)
Dana Myers (dana@devnet.la.locus.com)
Phil Ngai (phil@brahms.amd.com)
Steve Nuchia (steve@eddie.mit.edu)
Dev Palmer (wdp@dukee.egr.duke.edu)
Ahmed Shamim (ahmed@nicsa.ircc.ohio-state.edu)
Norm Strong (strong@tc.fluke.com)
David Thomas (bbx!yenta!dt@unmvax.cs.unm.edu)
John Woods (john@frog.UUCP)


--
Kenneth B. Streeter         | ARPA: streeter@im.lcs.mit.edu
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