STM32G474 HRTIM PWM仅主定时器比较值大于70ns时正常工作故障咨询

开发环境与需求 #

• 开发环境：STM32CubeIDE 1.7.0
• 硬件平台：STM32G474芯片
• 功能需求：实现4路PWM通道，支持5°间隔移相（示例配置：A=0°、B=5°、C=10°、D=180°），PWM占空比固定为50%，核心指标为通道间移相精度。

实现方案 #

主定时器配置 #

• HRTIM输入时钟为170 MHz
• 主定时器PWM频率为1.6 MHz
• 预分频倍率为HRTIM时钟倍频32，fHRCK = 5.44E9 Hz
• 周期值计算：HRTIM_INPUT_CLOCK * 32 / TIMM_PWM_FREQ = 3400
• 主定时器配置4路比较值，计算规则为masterCompareN= period/360*shift

定时器A~D配置 #

• 预分频倍率为HRTIM时钟倍频32，fHRCK = 5.44E9 Hz
• 每路定时器配置1路比较值，计算规则为(masterCompareN + (period/2)) % period

逻辑规则 #

主定时器对应比较事件触发对应通道输出置高，对应定时器自身比较事件触发通道输出置低。

故障现象 #

当所有通道移相角度≥8°（对应70ns）时输出符合预期，低于该阈值如A通道移相5°时偶尔无输出，疑似对应比较事件未生效。

测试波形对应移相值：A(红)2°、B(蓝)5°、C(绿)7°、D(黄)10°。

HRTIM初始化代码 #

// static void MX_HRTIM1_Init(void)
// Master Timer
LL_HRTIM_TIM_SetPrescaler(HRTIM1, LL_HRTIM_TIMER_MASTER, LL_HRTIM_PRESCALERRATIO_MUL32);
LL_HRTIM_TIM_SetCounterMode(HRTIM1, LL_HRTIM_TIMER_MASTER, LL_HRTIM_MODE_CONTINUOUS);
LL_HRTIM_TIM_SetPeriod(HRTIM1, LL_HRTIM_TIMER_MASTER, TIMM_PERIOD);
LL_HRTIM_TIM_SetRepetition(HRTIM1, LL_HRTIM_TIMER_MASTER, 0x00);
LL_HRTIM_TIM_DisableHalfMode(HRTIM1, LL_HRTIM_TIMER_MASTER);
LL_HRTIM_TIM_SetInterleavedMode(HRTIM1, LL_HRTIM_TIMER_MASTER, LL_HRTIM_INTERLEAVED_MODE_DISABLED);
LL_HRTIM_TIM_DisableStartOnSync(HRTIM1, LL_HRTIM_TIMER_MASTER);
LL_HRTIM_TIM_DisableResetOnSync(HRTIM1, LL_HRTIM_TIMER_MASTER);
LL_HRTIM_TIM_SetDACTrig(HRTIM1, LL_HRTIM_TIMER_MASTER, LL_HRTIM_DACTRIG_NONE);
LL_HRTIM_TIM_DisablePreload(HRTIM1, LL_HRTIM_TIMER_MASTER);
LL_HRTIM_TIM_SetUpdateGating(HRTIM1, LL_HRTIM_TIMER_MASTER, LL_HRTIM_UPDATEGATING_INDEPENDENT);
LL_HRTIM_TIM_SetUpdateTrig(HRTIM1, LL_HRTIM_TIMER_MASTER, LL_HRTIM_UPDATETRIG_NONE);
LL_HRTIM_TIM_SetBurstModeOption(HRTIM1, LL_HRTIM_TIMER_MASTER, LL_HRTIM_BURSTMODE_MAINTAINCLOCK);
LL_HRTIM_ForceUpdate(HRTIM1, LL_HRTIM_TIMER_MASTER);
LL_HRTIM_TIM_SetCompare1(HRTIM1, LL_HRTIM_TIMER_MASTER, TIMM_Compare1);
LL_HRTIM_TIM_SetCompare2(HRTIM1, LL_HRTIM_TIMER_MASTER, TIMM_Compare2);
LL_HRTIM_TIM_SetCompare3(HRTIM1, LL_HRTIM_TIMER_MASTER, TIMM_Compare3);
LL_HRTIM_TIM_SetCompare4(HRTIM1, LL_HRTIM_TIMER_MASTER, TIMM_Compare4);

// Timer A
LL_HRTIM_TIM_SetPrescaler(HRTIM1, LL_HRTIM_TIMER_A, LL_HRTIM_PRESCALERRATIO_MUL32);
LL_HRTIM_TIM_SetCounterMode(HRTIM1, LL_HRTIM_TIMER_A, LL_HRTIM_MODE_CONTINUOUS);
LL_HRTIM_TIM_SetPeriod(HRTIM1, LL_HRTIM_TIMER_A, TIMM_PERIOD);
LL_HRTIM_TIM_SetRepetition(HRTIM1, LL_HRTIM_TIMER_A, 0x00);
LL_HRTIM_TIM_SetUpdateGating(HRTIM1, LL_HRTIM_TIMER_A, LL_HRTIM_UPDATEGATING_INDEPENDENT);
LL_HRTIM_TIM_SetCountingMode(HRTIM1, LL_HRTIM_TIMER_A, LL_HRTIM_COUNTING_MODE_UP);
LL_HRTIM_TIM_SetComp1Mode(HRTIM1, LL_HRTIM_TIMER_A, LL_HRTIM_GTCMP1_GREATER);
LL_HRTIM_TIM_SetDACTrig(HRTIM1, LL_HRTIM_TIMER_A, LL_HRTIM_DACTRIG_NONE);
LL_HRTIM_TIM_DisableHalfMode(HRTIM1, LL_HRTIM_TIMER_A);
LL_HRTIM_TIM_SetInterleavedMode(HRTIM1, LL_HRTIM_TIMER_A, LL_HRTIM_INTERLEAVED_MODE_DISABLED);
LL_HRTIM_TIM_DisableStartOnSync(HRTIM1, LL_HRTIM_TIMER_A);
LL_HRTIM_TIM_DisableResetOnSync(HRTIM1, LL_HRTIM_TIMER_A);
LL_HRTIM_TIM_DisablePreload(HRTIM1, LL_HRTIM_TIMER_A);
LL_HRTIM_TIM_DisableResyncUpdate(HRTIM1, LL_HRTIM_TIMER_A);
LL_HRTIM_TIM_SetUpdateTrig(HRTIM1, LL_HRTIM_TIMER_A, LL_HRTIM_UPDATETRIG_NONE|LL_HRTIM_UPDATETRIG_NONE);
LL_HRTIM_TIM_SetResetTrig(HRTIM1, LL_HRTIM_TIMER_A, LL_HRTIM_RESETTRIG_NONE);
LL_HRTIM_TIM_DisablePushPullMode(HRTIM1, LL_HRTIM_TIMER_A);
LL_HRTIM_TIM_DisableDeadTime(HRTIM1, LL_HRTIM_TIMER_A);
LL_HRTIM_TIM_SetBurstModeOption(HRTIM1, LL_HRTIM_TIMER_A, LL_HRTIM_BURSTMODE_MAINTAINCLOCK);
LL_HRTIM_ForceUpdate(HRTIM1, LL_HRTIM_TIMER_A);
LL_HRTIM_TIM_SetCompare1(HRTIM1, LL_HRTIM_TIMER_A, TIMA_Compare1);
LL_HRTIM_OUT_SetPolarity(HRTIM1, LL_HRTIM_OUTPUT_TA1, LL_HRTIM_OUT_POSITIVE_POLARITY);
LL_HRTIM_OUT_SetOutputSetSrc(HRTIM1, LL_HRTIM_OUTPUT_TA1, LL_HRTIM_OUTPUTSET_MASTERCMP1);
LL_HRTIM_OUT_SetOutputResetSrc(HRTIM1, LL_HRTIM_OUTPUT_TA1, LL_HRTIM_OUTPUTRESET_TIMCMP1);
LL_HRTIM_OUT_SetIdleMode(HRTIM1, LL_HRTIM_OUTPUT_TA1, LL_HRTIM_OUT_NO_IDLE);
LL_HRTIM_OUT_SetIdleLevel(HRTIM1, LL_HRTIM_OUTPUT_TA1, LL_HRTIM_OUT_IDLELEVEL_INACTIVE);
LL_HRTIM_OUT_SetFaultState(HRTIM1, LL_HRTIM_OUTPUT_TA1, LL_HRTIM_OUT_FAULTSTATE_NO_ACTION);
LL_HRTIM_OUT_SetChopperMode(HRTIM1, LL_HRTIM_OUTPUT_TA1, LL_HRTIM_OUT_CHOPPERMODE_DISABLED);

// Timer B、C、D配置逻辑与Timer A一致

排查记录 #

• 2021-10-15：添加__disable_irq()排除中断导致定时器寄存器重载的影响，确认故障与中断无关。
• 2021-10-15：查阅LL_HRTIM_TIM_SetCompare1()函数说明，要求比较值需≥3个fHRTIM时钟周期，fHRTIM为170MHz对应周期约5.88ns，3倍值为17.65ns；实测可正常工作的10°移相对应时延约12ns以上，0°移相偶尔可正常输出。

内容的提问来源于stack exchange，提问作者codeshredder726b