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ITTSB Blog Specific => ITTSB - Small projects by Kiriakos & User reviews => Topic started by: Kiriakos GR on December 19, 2019, 01:34:39 PM

Title: LED bench work light - TAKE APART - Repair - Piss poor Chinese LED controller
Post by: Kiriakos GR on December 19, 2019, 01:34:39 PM

Log entry 19 December 2019.

This time I am exploring ways at bring back in action of one LED bench work light , from the ones that people buy for 15Euro and throwaway them at first sign of malfunction.   :P
Another example of helping capitalism of China with out you getting something reliable.

But this is not an 100% Chinese generated problem, when western bureaucrats and their bosses they assisted the huge campaign in favor of LED lights by them be aware that they are sort-lived due the electronic circuit which comes with it.
The hidden source of EVIL for our wallets this is the LED (power supply) controller - Driver circuit, which in case of damage this also destroying entire chain of 80% of LED in this circuit.

I found as a dead gift this LED (Fixture), aluminum rod, transparent cover,  72 LED in pairs of two connected in series, and nothing else.
My second gift was a double in length PCB with dead LED attached from a similar LED bench work light with out any housing.
I did manage to transfer a few alive LED and replace the damaged ones at the 90 centimeter long  bench work light that I am trying to restore.

I did manage to combine four DCV sources in series so to get 109 Volts DC for making my own quality control test.    

My new problem ?   with out an appropriate LED controller -Driver, or with out making an costly but safe 110V DC power circuit, I will not be able to use my finding and gift.     


Dead LED removal this is easy when using a well designed and decent in quality Hot-air rework station at 200C.
Soldering of LED this requiring chisel shape tip (which I did never get any) among with a quality soldering station which I do own one.

This topic it is now research in progress.

At my next step of progress I will add my next log entry.

Title: Re: LED bench work light - TAKE APART - Repair - Piss poor Chinese LED controller
Post by: Kiriakos GR on December 22, 2019, 12:26:30 PM

I am having partial progress here.  :)

About a year ago I did assembled a DC-DC booster 8VDC In / Out ADJ up to 60VDC.

New combined DCV from power sources sum gives me a total of 135V Max.
Now I do perform a crash-test to verify that LED’s which I did replace among healthy ones they are all truly robust.   

Title: Re: LED bench work light - TAKE APART - Repair - With NEW WS3441 LED controller
Post by: Kiriakos GR on December 30, 2019, 06:30:46 PM

Log entry 30 December 2019.

I was lucky enough to get in my hands of one smart LED driver controller, the Chip is made by WINSEMI Shenzhen.
Part number WS3441,  actual package WS3441D7P.
This has adjustable due resistors configuration, max output voltage and constant current.

The PCB which I found this was poorly configured from the PCB maker.
Now I am trying to get help from WINSEMI Shenzhen, so to correct old mistakes and making it usable.  ;)