Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => A20 => Topic started by: aauer1 on October 18, 2013, 07:47:27 PM

Title: A20 + 7 inch LCD flickering
Post by: aauer1 on October 18, 2013, 07:47:27 PM
Hi,

I use a board similar to the A20 micro together with a 7" LCD (the same as Olimex sells). What I see is that the LCD is a bit flickering (not the full display area only some parts). It seems like some parts of the display are sometimes varying in their brightness. It's hard to explain how it exactly looks.
But maybe someone has experienced similar issues with the 7" LCD!? Maybe someone also knows what's the reason for this.

Thanks,
Andreas
Title: Re: A20 + 7 inch LCD flickering
Post by: Lurch on October 18, 2013, 10:09:35 PM
Quote7" LCD (the same as Olimex sells)
Is it the Olimex LCD or your own?  Sounds like an improperly dimensioned voltage step-up circuit which can't keep the backlight current constant.
Title: Re: A20 + 7 inch LCD flickering
Post by: aauer1 on October 19, 2013, 11:06:09 AM
Quote from: Lurch on October 18, 2013, 10:09:35 PM
Is it the Olimex LCD or your own?  Sounds like an improperly dimensioned voltage step-up circuit which can't keep the backlight current constant.

You were right. The step-up circuit for the 10.4V voltage was a bit unstable due to a capacitor I assembled wrong.
Thanks for pointing me in the right direction!