I'm building a switch-mode power supply (synchronous boost voltage regulator), and want to control the duty cycle and the phase of two PWM outputs (frequency in the 100kHz - 125kHz range). For proof-of-concept, I've been using an Arduino-compatible dev board (from Adafruit) with an ATMega32u4. I've been using Timer4, and I can control the duty cycle of the two PWM4A / PWM4B outputs independently but I haven't been able to adjust the phase relationship. I've spent some time looking through the ATmega16U4/ATmega32U4 datasheet and testing Fast PWM mode, Frequency Correct PWM mode, as well as various settings for the DT4 Dead Time value registers. I have not attempted using PWM6 mode yet.
I don't necessarily need to use the 32u4 processor. If it's not possible to adjust the phase relationship of the two PWM outputs, I'm interested to know if there are other AVR (or non-AVR but still Arduino-compatible) controllers that might be more suitable. When I first started the project I thought I could get by with a simple boost regulator with a single PWM output, but it turns out I need a synchronous FET in parallel with the catch diode to keep the efficiency high.
Attached oscilloscope screenshot shows the PWM4A and PWM4B outputs, with scratch notes showing how I want to adjust the phasing.
Thanks in advance,