AnsweredAssumed Answered

LCD pixel noise

Question asked by smith.greg.005 on Sep 13, 2017
Latest reply on Sep 14, 2017 by smith.greg.005

I'm working on a board that is close to the 429 Discovery board, using:

- STM32F429 micro

- LTDC connection to a custom 3 inch LCD using ili9327 controller, connected via display pixel interface

- IS42SI6400J SDRAM used as frame buffer

- STemWin library using linear display driver

 

I'm getting some pixel noise on the right side of vertical edges, uniformly across the screen, that is colour dependent.

Red and Blue are OK. Green is bad. Shades of white/grey are also bad.

 

Here's a video of it: 20170913 184943 - YouTube 

 

We've tried 2 different displays and 2 different board layouts. Last layout is a 4 layer board with careful attention to track lengths and routing, as per the ST guidelines. In all cases the same symptoms are present.

I've also tried a variety of settings for front/back porch etc, but nothing helps.

 

Does anyone have any suggestions that might help to solve this?

Thanks.

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