So I'm in need of a PWM expander for my project. I need at least 11 PWM signals, but more is better for future expandability. I was initially looking at the TLC5940, but because I need the channels to control mosfets and ssr's, a current sink chip would not work. Can anyone give recommendations?
Certainly an option. Are there any ICs like the TLC5940, but that are current sources? I don't know how I feel about dedicating 20-30% of the processing power to PWM.
You can use current a current sink. Connect your gate through a pull-up resistor, then connect the gate to the sink. when it turns on, it will go low, bringing the gate low. This means all of your signals will be inverted, but it might work. Also you can use another small MOSFET in the same way to act as an inverting circuit.