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crwdns2933797:0Pavel Hanakcrwdnd2933797:0crwdne2933797:0
crwdns2936043:0crwdne2936043:0 crwdns2933505:0crwdne2933505:0 Pavel Hanak
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+ | [title] Backlight schematics |
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+ | [* black] I analyzed original backlight connections and it's apparent why it fails: the Chinese comrades who designed the display wanted to save some money and/or space and connected the LEDs in parallel. |
+ | [* black] Of course, every LED has slightly different threshold voltage. As a consequence, one of them draws more current and fails (burns open) prematurely. The remaining two LEDs are then subjected to even higher currents and burn soon afterwards, too. |
+ | [* black] Thus I decided to change the connection according to the lower schematic - I shorted the original 22R resistors and put a 220R resistor in series with each new LED. |
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