I can’t seem to find a good answer to whether or not you can group channels on the LP55231 Breakout Board to drive higher current LEDs. Is there any reason why it wouldn’t work? I am trying to power 100mA IR LEDs. I know there are other ways to do this but for my application this is the solution I am exploring.
I don’t think that would work unfortunately, it would be possible for one output to be on while another is off resulting in a direct short circuit. You might be better off using a resistor to limit current on your LED and a transistor to turn it on and off.
Hi TS-Chris,
ah damn that is what I was afraid of. Yeah the issue is I am out of IO on my board and can’t find a good i2c based small, low power low channel count IO expander with PWM that can drive a transistor. Know of anything?
It’s not low channel, but [BOB-13601 might work for you. You might be wasting outputs, but at $5.95 you’re not losing too much. ;-)](https://www.sparkfun.com/products/13601)
Yeah I was evaluating that as well. Seemed like a decent fit. Picked through the library and the datasheet and it wasn’t clear how to make the PWM source instead of sink. Is it even possible to have them source as PWM? If I can only turn things on and off that isn’t the end of the world but not as good.