TLC59108, no brightness?

Hey guys,

I’m looking for some LED drivers to drive a bunch of LEDs (4 of them) at about 100mA (might be more in the end, but 100 should do the trick).
I came across the TLC59108, which seems to do what I want.

So I ordered a few of them, soldered them on a nice (failed) breakout, but I can’t seem to get more than 1mA high off running through the LEDs.

I’m currently trying on LEDs that should hold about 40mA.

Rext is 330Ohms connected to ground, I kind of guesstimated it as the datasheet is a bit obscure, but their calculation seem to say I should expect a current of 15*1.25/330 = 0.05A, so 50mA. Might be a bit much, but the LED should just end up being too bright and eventually burn if done for a long time.

I’m using the library found here and run the example. I can see the LED turn on and off.

The device does answer on the I2C bus (using i2c scanner).

The LED is working when simply put between Vcc and GND (with a resistor).

Anyone used this successfully yet? I’ve tried 2 of those chips already and can’t figure it out…
Other solution is: what kind of other options do I have for a quick constant current driver that could handle 4 LEDs without being a pain in the butt?

Picture of the setup is attached, it’s a bit messy but it seems correct…

Forgot to say, I’m using a Leonardo (or well, a copy), and everything is powered through an usb3 (which should be fine)


How about a schematic?