/STM32G474-BUCK-Converter

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STM32G474CET6 HRTIM Configuration

This demo configures one channle high resolution pwm output using the hrtim of stm32g474cet6.

let's see how i do it.

1st. select TA1 output active at the pull bar of TimerA

image-20210222202012349

2nd. set the period which decide the PWM frequency which can be calculated like this.

5.44E9Hz / 27200 = 200000Hz

image-20210222202300310

by the way, if you want to generate a pair of complementary PWM, you can insert a dead time by selecting deadtime is inserted between output1 and output2 which is shown in the picture downbelow.

image-20210222202534779

Now go back to the topic.

3rd. For Compare Unit 1 section change the configuration setting to Enable. Enter a Compare Value of 13600. This is the initial value of the duty cycle fixed to 50%. The compare event is used later on as a reset source to clear the output.

when the counter come to this value, a timer compare event will be generated

you can also enable other compare unit and set the compare value. You can use them for ADC trigger event. This trick is talked in another branch in this repo.

image-20210222202900686

4th. set the Set Source Selection to 1 , and the 1st Set Source will come up, its defult content is Timer period event forces the output to its active state, which means the PWM output will be set to low level every time the timer count from 27200 to 0. We will leave it there, we don't modify it.

also, set the Reset Source Selection to 1 , and the 1st Reset Source will come up as well, its defult content is Timer period event forces the output to its inactive state, whose meaning has been explained just now. Here, we will modify it, select Timer compare 1 event forces the output to its inactive in the dropdown list. This is the event that decide the PWM duty circle.

image-20210222203929370

that's all for the hrtim configuration, then you can generate code to keil MDK.

then use this function to start the PWM output.

HAL_HRTIM_WaveformCounterStart(&hhrtim1,HRTIM_TIMERID_TIMER_A);
HAL_HRTIM_WaveformOutputStart(&hhrtim1, HRTIM_OUTPUT_TA1);

you can change the freq by changing hhrtim1.Instance->sTimerxRegs[0].PERxR, which you have set to 27200 in the cubeMX.

and you can set the compare value which decide the pwm duty circle by changing hhrtim1.Instance->sTimerxRegs[0].CMP1xR , which you have set to 13600 in the cubeMX.

for other timers, refer to this

sTimerxRegs[0]---->TimerA sTimerxRegs[1]---->TimerB sTimerxRegs[2]---->TimerC sTimerxRegs[3]---->TimerD