Hi all,

I tried to drive the BT-136 triac (220 volts AC) with following scheme.


MT2 ----> AC pahse in.

MT1 ----> AC out to lamp.

Gate ----> P3.7 thru 3.9 k resistor.

MT1 -----> to +5 Vcc of 2051.

AC neutral -----> Lamp.

micro's supply is thru transformer.

It is supposed to turn the lamp on when <clr p3.7> and off when <setb p3.7>.

But lamp stays on and on..........

Port is working OK. It blinks an LED fine.

I have seen PICs that drive traics that way.

Please help

Rovan