Posted on August 18, 2017 at 15:22Hello!
I am evaluating MCUs for advanced power supplies. The MCU should become our standard MCU for the digital power conversion applications. We typically have an (interleaved) buck, a full/half bridge and a synchronous rectifier. So I need at least 5 PWM units with two complementary outputs per unit. It must be possible to synchronize the PWMs and to have arbitrary phase shifts between the PWMs. Comparators are also mandatory and Hrtim is beneficial.
I found the stm32f334 as an interesting candidate. I played around with and “STM32F3348 Discovery Board and read the HRtim cookbook, but I still have some questions.
@Phase
If I understand correctly, they did arbitrary phase shifts in the STEVAL-ISA172V2 as described in the AN4856. Is this code available?
@Triangular vs Sawtooth reference
For some application we have used triangular references (up/down counter), because a duty cycle change has no influence on the phase between PWM units. Can I use to compare values (period +/- DC/2) to emulate an up/down counter.
@Peak current Mode control
Is it possible control the PWM duty cycle with the comparator for a digital peak current Mode controller?
Last but not least is the stm32f334 a good chose or should I use another MCU?
-Thomas
