I'm working on a project that interfaces with a Leviton LVS-8W pushbutton wall plate (http://www.leviton.com/en/products/lvs-8w). I was really hoping to use a TLC5940 chip to drive the LEDs inside each button, but the wall plate is designed for a 24v supply (LEDs are wired common-anode). Unfortunately, the TLC5940 datasheet says that the LED power supply maxes out at 17v.
I'm expecting that I do not need the TLC5940's current limiting feature (I haven't confirmed it yet, but there must be current-limiting resistors built into the wall plate already). I don't need high current (probably only a few milliamps per LED). I may be able to simply drop my supply voltage to, say, 16v, but I'm afraid this might make the LEDs too dim.
Is there an alternative to the TLC5940 that might work? Any way I can get around the power supply limit? My PCB design is pretty tight already, so I'm hoping I don't have to add a transistor to each output.
Am I just hoping for too much?