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Flickering white led on membrane switch

image.jpg I have a customer who is experiencing a flicker on a 1206 white LED on a membrane switch which has typical values of 20mA at 3v but is using 5mA and 2.85v and the attached circuit, is this circuit creating frequency modulation at a rate visible to the eye ?

Would appreciate any input
 

KrisBlueNZ

Sadly passed away in 2015
Neale, you had posted this question six times on an unrelated thread. I have moved it to a new thread.

What is the thing at the bottom left corner of your schematic? Is it a microcontroller that is using PWM to control the LED brightness?

Do you have an oscilloscope? If so, look at the voltage on those control signals, and the voltage across the LED. Post a photo of the oscilloscope trace here.
 
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