RA8875 display controller with display current problem

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l_l_l
 
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RA8875 display controller with display current problem

Post by l_l_l »

Hi,

I recently bought the RA8875 driver board (ID 1590) and the 4.3" touch display (ID 1591). To test it, I conneceted them and hooked up Vin and GND to my lab power supply at 5V. With this setting I encounter the following behavior/problem:
The backlight lights up very shortly, and then turns off after a tenth of a second or so. To avoid that, I have to limit the current on my supply to around 100 mA.

I made the following measurements:
Controller board without anything connected to it: 18 mA at 5 V
Controller board with display with current limit: 119 mA at 1.6 V (highest current without display shutoff)
13 V on one display connection pin, I guess that's the backlight power.
After backlight shutoff, the controller draws slightly more current (21 mA).
I couldn't find any warm or hot device on the PCB.

I saw the solder bridges on the back, but they're already connected somewhere.

Is there some damage on my controller board or the display?
Or can this behavior have some other reason?

Thanks for help!

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adafruit_support_rick
 
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Re: RA8875 display controller with display current problem

Post by adafruit_support_rick »

Please email [email protected] with a link to this thread for a replacement RA8875 controller board

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