I'm using an existing keypad with 8 LEDs that source power. I was hoping to use and LED driver of sorts, but all of the ones I find only refer to sinking power. Is it possible to use these drivers to source current, and if so is there a way of understanding how to convert the sinking specifications to sourcing? The Vcc for my system is 3.3V and LEDs are 3.4V and 20mA
Was looking at [this TI TLC5917 driver][1].
The LEDs on keypad are [Lite-On LTST-C150TBKT][2].
The circuit is setup like
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[1]: http://www.ti.com/lit/ds/symlink/tlc5917.pdf
[2]: http://www.mouser.com/catalog/specsheets/Lite-On-LTST-C150TBKT.pdf