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Electronics => Repair => Topic started by: Emi on December 19, 2019, 07:24:27 am

Title: Pwm driver misterious chip..MCU or standard?
Post by: Emi on December 19, 2019, 07:24:27 am

Hi ;)
I'd like to discover if a scratched pwm driver can be "unveiled" .
Board is a classical chinese LY-820 pwm driver  but (god damn them)  has the chip grinded !!!
Could be a tl594 similar..
It drives a mosfet and has only few caps and resistors around..

Can you help me?

Title: Re: Pwm driver misterious chip..MCU or standard?
Post by: Circlotron on December 19, 2019, 07:29:58 am

 Would be handy to show the other side of the board as well so we can see where the tracks connect to.

Title: Re: Pwm driver misterious chip..MCU or standard?
Post by: Emi on December 19, 2019, 07:31:18 am

 Ok..i will post a pic later ;)
Grabbed on web..but Nice
Could it really be a tl "something"?
494?

Title: Re: Pwm driver misterious chip..MCU or standard?
Post by: fzabkar on December 20, 2019, 07:15:26 pm

The Vcc and Ground pins match a TL494. I would draw a circuit diagram.

Title: Re: Pwm driver misterious chip..MCU or standard?
Post by: Emi on December 26, 2019, 10:25:52 am

Thanks fzabkar. ..meanwhile i've casually found the solution in a Russian lathes forum. . ( chipmakers.ru)
It ' really a tl494 very common chip ;)
The guy here developed some mods to improve original
Performances..
Thanks for your interest  :-+