Hi Greg.

17-Dec-03 08:48:00, Greg Mayman wrote to Roy J. Tellason

 GM> 1. FET turns on, driving the LED of the opto. 2. The opto's output
 GM> connects between anode and gate of the SCR, turning it on when the
 GM> opto is driven. 3. The SCR shorts the DC side of the bridge,
 GM> giving a near short circuit on the AC side. 4. The AC side of the
 GM> bridge is connected between anode 1 and gate of the Triac maybe
 GM> with a series limiting resistor. When current flows in this path
 GM> the Triac is turned on.

 GM> It could have been done more simply with a relay.

Or a triac driver like MOC2031, basically an optocooupler, but the
output stage is like a 400V/100mA triac (or silicon bilateral switch)

 -=> Bye <=-
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