Author Topic: Reliability problems on NHD-0420CW-AB3  (Read 119 times)


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Reliability problems on NHD-0420CW-AB3
« on: January 13, 2020, 03:47:48 AM »

we designed an electronic board with the NHD-0420CW-AB3 display and we have some faulty devices.
As shown in the attached picture, the pixels that makes each character are not fully clear with the same brightness.
The display is driven through I2C and pin 2 and pin 3 of the display interface are at +5VDC.
What could be the reason of the failure?
The failures emerged after only one month @ 25 deg C constant temperature.
Thanks, regards.



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Re: Reliability problems on NHD-0420CW-AB3
« Reply #1 on: January 22, 2020, 03:42:57 PM »
Hello ademarco,

Unfortunately our NHD-0420CW-AB3 display does not support I2C interface at 5V conditions, which could be why you are experiencing issues even at normal operating temperatures. We have known of this issue on Slim Character OLEDs which affects its operation when used in I2C mode at 5V conditions, and have reflected this appropriately in our datasheets.

I2C interface has been tested, verified, and can be safely operated at 3.3V or low operating voltage conditions, and both parallel & serial interface conditions are supported at both low operating voltage and 5V conditions.



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