>You won't get 5 amps out of an LM317 without a bunch of extra parts.

        Maybe you can get from the TO-3 LM317. But be sure you gotta use a BIG=
 active heatsink (e.g.: with a fan)

>I built a nice little bench supply with a PIC running a P-Channel pass
>transistor, threw in an inductor and a capacitor and two pushbutton inputs
>to the PIC.  The PIC senses output voltage, and turns the pass transistor
>on
>and off.  The two pushbutton inputs run the setpoint up and down.  A=
 little
>digital panel meter serves as the interface, you just push the UP button=
 if
>you want the voltage higher, etc.  None of the part values seemed to be
>very
>critical, worked pretty good first time with junk parts off my bench.

        Hmmm, Miss the times where we used simple zeners or UA723 for regulating=
 power ;o)

>Running behind a stable 24V power source it seems to give pretty good
>regulation and will provide lots of current if required, will dial down to
>less than .25 volts, and can be adjusted in micro-increments.  Used a
>16F873
>so I could use the 10 bit A/D for lots of fine adjustment.

        Wow, that's nice! ;oD

>Of course there are 1000 circuits using LM317's plus pass transistors.  I
>just wanted to build a switcher with a PIC in it, so I could slap a=
 sticker
>on it saying "PIC INSIDE!"

        Hahaha, nice touch ;o)


---8<---Corte aqui---8<----

Alexandre Souza
taito@terra.com.br
http://planeta.terra.com.br/lazer/pinball/

---8<---Corte aqui---8<----

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