I have some of these (VO3023) and am wondering if and how I can use them in a specific project where I will be driving them with an Arduino Pro Mini using digitalWrite. I've never used optoisolators before.
Here's the datasheet:
http://www.vishay.com/docs/84132/vo3020.pdfHere are my questions:
1. Do I have to use a resistor on the input to the chip to protect the internal LED? It looks like the trigger current is listed as 5mA, so that would mean a 1K resistor for a 5V signal, right?
2. Most circuits I see using this kind of optoisolator drive an external triac. Why would I need that since this has one internally?
3. If I do use an external triac, what purpose do the resistors (56R and 100R) in a circuit like this perform:
https://www.electronics-tutorials.ws/articles/opto6.gif4. How much current can I pass through the internal triac? Is that the "RMS On State Current"?
5. Finally, probably the biggest question - I need to use it to turn a DC line on and off that may have it's polarity reversed (i.e. positive and negative are reversed sometimes). Is this OK with a triac, and how do I calculate the current when specs are written for RMS?
Thanks in advance to everybody.