Sink current using PCA9685?

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Glviybalspec's picture
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Sink current using PCA9685?

I’m using a LED driver PCA9685 with a pinout board like Adafruit’s. I’m trying to run a bunch of LEDs at 20 mA, and the chip is supposed to be able to source 10 mA and sink 25 mA. I understand that to have it Source, you connect the LED between the PWM and GND pins and to Sink you connect it between V+ and PWM.

I’ve tried both ways and using a multimeter and a red LED I get 12.5 mA. Why is it not 25 in Sink? Also, why do I get 12.5 on Source mode as well?

Is there anyone have ideas of it? Many thanks.