-----Original Message-----
From: Jim Ruxton <cinetron@PASSPORT.CA>
To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
Date: Thursday, May 13, 1999 12:20 PM
Subject: Driving Back to Back SCR's from PIC or Where do I Find a Cheap
Triac


>Hi Everyone,
>
> I'm trying to figure out how to drive 2  inverse parallel SCRs. From a
>PIC to control a full wave AC load. I am using a cheap and dirty non
>isolated power supply so my pic ground is sitting at neutral. Driving
>the one SCR that has its Cathode on the neutral line is no problem but
>driving the one that has its' Anode attached to neutral is the problem.
>I would use a triac but can't find one as cheap as the two SCRs. If any
>one knows where to get a cheap sensitive gate triac in a TO92 package
>for about 8 cents in quantity of 250K I'd love to hear about it or knows
>how to drive a full wave AC. load with one SCR from a PIC using a
>nonisolated supply , even better.
>Thanks
>Jim
>
>------| |---


how about this solution
http://www.vertonet.com/members/pvh/scr.pdf i'm also ascii art impaired but
can use drawing software

basicaly a scr in a full wave bridge in series with the load
get power for the pic from the other side of the load with diode, cap and
resistor in series.


Peter