CFAF176220U-020T (2Bit Micro) complete backlight disabling

[MM2forever]

Hello Forum members,

I'm for a long time now dealing with the problem that my CFAF176220U-020T display (the one on the 2Bit Micro carrier board) cant have its backlight fully turned of.

Is this a bug (or a feature) ?

I attached the Backlight enable/disable pin to my PIC32 microcontroller and toggle it to turn of the display backlight, but in my case it just "dims" the display.

What am I doing wrong?


Thanks for your help

MM2forever

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[cosmicvoid]

What happens if you disconnect the backlight en/dis pin from your PIC32, and connect that pin directly to ground?

I am thinking that if the backlight is still "dim", then there may be a defective B/L controller chip on the 2BM board.

I have this LCD display, but it is not mounted on the 2BM carrier, so I am just giving ideas based on the documentation.

 

[MM2forever]

Thanks for your answer!

Maybe its rather a feature of the Backlight controller?

I grounded it directly and its still dim, I measured the Voltage coming out of the PIC Pin when it should be low and its 0.04V (basically 0).
Anyone who has it on 2BM carrier board? Maybe its supposed to be like that?

 

[cosmicvoid]

Maybe its rather a feature of the Backlight controller?

I doubt that. But since there is no schematic info for the carrier board, I can't advise you any further. I think CFA tech support will need to answer this one.