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Per the title really, I've been battling with (very VERY similar) MIPI screens from a few suppliers and they've been throwing different timings and configs / initialisation sequences at me... well, to verify one of them I used config A on screen B, which seemed to work briefly but now the screen has a load of grey lines across it and a weird halo pattern - and no picture.

Screen A and Screen B both use the same controller IC (FocalTech OTA7290) configured basically the same way with the same panel layout but one supplier gives radically different setup instructions for reasons they can't or won't elaborate on.

It seems wild to me that it would be possible to physically damage a screen just by having incorrect video timings but it sure looks a lot like it.

John U
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2 Answers2

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I would think not (with caveats), try the screen in something you know works with it. You can damage the screen if you are applying a different voltage or differential current that is outside of the recommended specs. Check the voltage and current characteristics of the drivers and all the power lines.

If you are still getting issues with the screen hook up a scope and verify the timing, you could be having noise on the signal lines.

Also check the ground voltage across the screen cable to make sure it's good. I've had screens that had RF issues with noise traveling up the cable and creating an antenna of the screen ground and causing ground bounce.

Voltage Spike
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Well the answer appears to be "No" as the screen has now come back to life with previous known-good settings but it was definitely unhappy for a while before going back to normal.

A colleague says he's seem similar behaviour from other LCD's in the past - so it looks like they can build up a little "memory" or something, enough to worry you for a while, but will come back to normal after some time.

John U
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