Thanks, I would like to try all methods one by one... but the component suppliers here are simply too not competitive... Imagine they don't even have optocouplers and triacs in store...
I would like to tryout a capacitive dropper, which the components are more of a hope to be available here.
With a 225K capacitor parallel to a 470K resistor at the L arm, as the dropper; 100ohm resistor at the N arm.
The two arms are connected to rectifier (I'm planning to use 4 1N4007 diodes as bridge), a 1000uF smoothing capacitor,
100ohm bleeding resistor, and finally 5.1V Zener diode to get a 5Vdc logic level into the microcontroller.
Will this work? How do I choose the ratings for the components, I do realize this requires isolation, but that doesn't matter for the time being.
Is there any other drawbacks on this design?
Please advice... Thanks
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PC817 input side and output side max current is 50 mA according to datasheet. Why do you want to know minimum current? Why don't you just provide 10 to 15 mA and see?
I need to know the minimum operating current, I have a SFH620A now, I connect 5 470ohm resistors to each AC arm and to the input pins of the opto; which makes a total of 4.7K ohm. The opto wouldn't activate...