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Topic: Control 60 individually white leds (no led strip) (Read 499 times) previous topic - next topic

Shuzz

Its it possible your pins were set to INPUT_PULLUP? The internal pull-up resistors are equivalent to ~50K and would source around 5/(50K)=0.1mA, which sounds much more like what you are describing.
I was unable to find an explanation for the behaviour when it happened.
The code would set all pins involved to INPUT, disable all pullups and then set the pins required to OUTPUT and LOW or HIGH, respectively.
Ultimately, I switched the original LEDs to WS2812 because the project suddenly required somewhat more fancy effects... ;-)

In any case: you're correct, I re-checked the datasheet and the impedance should be high enough to prevent any residual glow. Maybe I had a faulty chip? I don't know.

PaulRB

It's possible that if you had an output set to OUTPUT & HIGH and then set it to INPUT, that the internal pull-up gets/remains enabled.

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