How to use pc817 and tip122 to control rectified mains LED array?

I have 3sets of leds that conduct at 250v so I wanted to use my 100v TIP122 NPN(with TVS diodes to protect it from over voltage) and PC817 opto-isolator to PWM the LEDs which are common cathode, is there a way?
Thank you all for all the superb suggestoins!

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iceng4 months ago

Your PC817 opto-isolator is only able to handle 80V and TIP122 is only a 100V 5A Darlington NPN..

I never design a transistor switch without 150% Voltage safety.. LEDs may not turn on, but they do not start blocking at a magic value, especially a module..

If you know how to use a voltmeter put it in place of the Tip122 !

Included is a simple way to light anything from a uP..

OPTOISO-Triac-Triac-LED.JPG
yagoa (author)  iceng4 months ago

I think your circuit would have a higher BOM, since the led conduct only within this 100v range, even 70v range worked ok, do you know any good 100v opto-isolator? The PWM would also be better with the transistor right?

yagoa (author)  yagoa4 months ago

I dont really need a multimeter check since I will have a tvs or zener diode to protect the transistor and optocoupler

yagoa (author) 4 months ago
LTV-358T seems to be a great optoisolator for this situation
yagoa (author) 4 months ago

the opto-isolator is only 35v that is the issue

Screen Shot 2017-05-27 at 19.09.11.png
yagoa (author)  yagoa4 months ago

It is rectified 220VAC, 310-320VDC

Iceng's scheme with a triac is a good one, and easy to make.

steveastrouk4 months ago

You don't have any suitable parts for the voltages you want to work with.

Downunder35m4 months ago

No clue without proper info ;)