I have a Triac that I want to use to control low voltage (~16 V) AC. The data sheet is found here. It specifies that the peak gate voltage is 5 V with a peak current rating of 2 A (which seems quite high to me). The datasheet also lists out the Gate trigger voltage as 0.7 V (typical).
I'll be using this opto-isolator to drive the triac gate, which doesn't seem to have much play in my question (but I could be wrong).
UPDATE: After some additional research it turns out that I was wrong here. The opto-isolator's max current is the determining factor for the gate resistor value. The iosolator used here has a max detector current of 1A. 16VAC has a RMS voltage value of 22.62VAC which leads to a minimum resistor value of 22.6 / 1 = ~22 ohms.
My question is which of these values should I consider when choosing a resistor to place before the triac's gate/opto isolator? I understand how a Triac and it's associated driver works but I just need a little assistance with reading the datasheet and which of the values I should be considering.
Also, are there any good resources for learning how to read datasheets or is this something that just comes with experience?
Best Answer
I think you have to design in term of current, that must be
>=to theGate Trigger currentin order to have the device ON. You can use the Gate trigger voltage as a voltage drop when you measure the current flowing in the gate in order to switch the TRIAC.