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Serial 634 Lcd Backlight


New member
Serial 634 Lcd Backlight (needs 5V)

I just got a Serial 634. It works fine but the backlight does not come on. do I have to 5V to it to get the backlight to work? :confused:

I ran wintest. everything works except the Backlight.


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Last edited:


New member
Sorry for this post. But the answer is: Yes to use the LED backlight, you need to provide 5V to it. Serial port power is used for low power only.

:) Nice white backlight :)

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