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  1. #1
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    LED headlight pcb reverse engineering

    Hello, everyone, I am new to this forum. I am a product designer who is looking to get better at electronics. I have played with very basic electronic such as arduino etc. I have a basic understanding so far of electricity in term of physics . I am currently working on a personal project. I am basically trying to understand this circuit and how it works. I have, I think made an approximate diagram by following the tracks and do a list of the componants to find what they were. So basically this PCB came from an motorcycle headlight which has low and high beam. It must be a very simple device, but I really want to understand how it works and what does each componant does in tha particular circuit. I would greatly appreciate your help, thank you very much in advance.


    The pcb

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    my diagram (I might be wrong) HB is for High beam and LB for low beam

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    And here is the list of the componant I ve gatherd besed on the code number.

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    Click image for larger version. 

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ID:	155312

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  2. #2
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    Re: LED headlight pcb reverse engineering

    The schematic doesn't make sense so there must be errors in it I'm afraid.

    It looks to be a low power headlight, maybe 3W at most so it can't be very bright. Even if both high and low beams are on together it probably doesn't exceed 6W. Trying to best guess at what it does, the small LEDs are on all the time, the big LEDs are either on full brightness for HB or chopped by the IC for LB so they drop in brightness. The values in the schematic do not make any sense though and the current flow through the LEDs is unclear.

    Brian.
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