This Triac have a better di/dt than the first one we selected for sure.. but it has also one bug. The Current gate should be at least 30mA.. and usually we double it for safety sake.. i said usually. So a bit demanding for a single PIC i/o... but for a few ten or hundreds uSec of hold time it may work without stressing too much the i/o. Two i/o in parrallel is maybe a better choice OR external driver.
Now you must filter the opto-transistor output as it will certainely pick-up more than the I/R spectrum. At least a high-pass filter will remove some mess. A simple R/C circuit on the PIC input? Maybe...
Is the current enough for the I/R led and for this application... i may have some doubt on it. This bring this LED driver stuff once again or use i/o in parrallel... wich never turned me on. even if it could work in theory.
all that new current need may probably be too much for the transformerless PSU.... but at the same time we still working with short pulses, and and and. Worth a try for sure. Keep the scope on the rails to see what's happen. Increase C3 (wich have to be 0.47uF and not 0.047 uF anyways 
) if much current is needed. You know my opinion of transformeless PSUs anyways...
So there's tons of maybe once again!
PS, i would certainely add a snubber for this TRIAC or use BTA216 instead... without snubber.
Last edited by mister_e; - 14th October 2006 at 21:12.
Steve
It's not a bug, it's a random feature.
There's no problem, only learning opportunities.
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