Is there a current-source equivalent of a TLC5940 (current-sink) PWM LED driver?
I'm working with a large number of linear resonant actuators (LRAs), each of which only uses ~50mA, but must be driven by AC (frequency is constant, amplitude determines power). Each has an independent amplitude from the others.
Currently I'm using PWM output from my MCU to drive the AC voltage in both frequency and amplitude using a PWM to voltage circuit. The involved PWM generation takes up a lot of MCU resources, both computational and pins.
I considered using a number of DACs, but the number I'd need is outside my budget.
I had hoped to use a TLC5940 to move the PWM generation outside the MCU, but as mentioned, it does PWM via current-sink which afaik won't work with the PWM-voltage conversion circuit I'm using.
Are there any other IC options that might work? I've considered using a TLC5940 to switch the ground on a bunch of MOSFETs, but I don't think that would work right (at least I can't find any references to using a MOSFET that way).