Author Topic: Is it possible to change the output voltage here?  (Read 1212 times)

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Offline Chet T16

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Is it possible to change the output voltage here?
« on: July 25, 2017, 06:57:47 am »
I have an LED driver here with an output of 72V, unfortunately it has an unknown IC so I've no datasheet to see how the voltage is set.

Presumably its a matter of changing a couple of resistors? Any pointers on where to start?

Thanks

Chet
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Offline Mechatrommer

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Re: Is it possible to change the output voltage here?
« Reply #1 on: July 25, 2017, 07:38:38 am »
I have an LED driver here with an output of 72V, unfortunately it has an unknown IC so I've no datasheet to see how the voltage is set.
Presumably its a matter of changing a couple of resistors? Any pointers on where to start?
i salvaged led light from dumbster (similar size as long flourescent tube). the chip driver is WS3441A offline non isolated led driver. its constant current driver instead of constant voltage. so i guess you put anything on the output, it will produce any voltage necessary to get the set constant current... the chip number is barely visible in the picture you posted, maybe you can clean some more and look the number under microscope, ymmv.
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Offline Zero999

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Re: Is it possible to change the output voltage here?
« Reply #2 on: July 25, 2017, 08:12:57 am »
I have an LED driver here with an output of 72V, unfortunately it has an unknown IC so I've no datasheet to see how the voltage is set.
Presumably its a matter of changing a couple of resistors? Any pointers on where to start?
i salvaged led light from dumbster (similar size as long flourescent tube). the chip driver is WS3441A offline non isolated led driver. its constant current driver instead of constant voltage. so i guess you put anything on the output, it will produce any voltage necessary to get the set constant current... the chip number is barely visible in the picture you posted, maybe you can clean some more and look the number under microscope, ymmv.
Yes, it's most likely it regulates the current, not the voltage, which is probably limited to 72V to protect the components. It's also quite likely it either isn't isolated from the mains at all or the insulation isn't adequate to enable the DC side to be treated as non-hazardous.
 

Offline Chet T16

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Re: Is it possible to change the output voltage here?
« Reply #3 on: July 26, 2017, 11:44:05 am »
Yes its non-isolated but it only needs to run for a short while under controlled circumstances for some testing.

I'll do some testing to see if it is indeed constant current.

Thanks
Chet
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