我现在在做一个STM32F0的实验，板子的电路图如下，当TIM2开启输出PWM波形后，OLED会变暗，别外一个板子还直接重启，是不是我哪里没有配置好的？找了好久一直没有找到原因，代码和电路图如下：
uint32_t ohm_freq = 238000;
uint16_t  ohm_percent = 500;

void OHM_GPIO_Init(void)
{       
        GPIO_InitTypeDef GPIO_InitStructure;
       
        RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOB, ENABLE);
       
        //Charge_PWM GPIO Port
        GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
        GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
        GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
        GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
        GPIO_Init(GPIOB, &GPIO_InitStructure);
        GPIO_PinAFConfig(GPIOB, GPIO_PinSource11, GPIO_AF_2);
       
        //DIO_Ctrl_Pin
        GPIO_InitStructure.GPIO_Pin = GPIO_Pin_14;
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
        GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
        GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
        GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
        GPIO_Init(GPIOB, &GPIO_InitStructure);
        GPIO_ResetBits(GPIOB, GPIO_Pin_14);
}

void OHM_TIM_PWM_Init(void)
{
        TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
        TIM_OCInitTypeDef TIM_OCInitStructure;
        uint32_t TimerPeriod = 0;
        uint32_t ChannelPulse = 0;
       
        TimerPeriod = (SystemCoreClock/ohm_freq)-1;
        ChannelPulse = ohm_percent*(TimerPeriod - 1)/1000;
       
        RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
       
        TIM_TimeBaseStructure.TIM_Prescaler = 0;  //预分频系数(48-1), t=48/48000000=1us, 即TIMx->CNT每1us加一次
        TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //向上计数模式
        TIM_TimeBaseStructure.TIM_Period = TimerPeriod;//TimerPeriod;  
        TIM_TimeBaseStructure.TIM_ClockDivision = 0;
        TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;
        TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
       
        TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
        TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
        TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
        //TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Reset;
        TIM_OCInitStructure.TIM_Pulse = ChannelPulse;//ChannelPulse;;
        //TIM_OC1Init(TIM2, &TIM_OCInitStructure);
        TIM_OC4Init(TIM2, &TIM_OCInitStructure);
       
        //放到Enable函数里面
        //TIM_Cmd(TIM2, ENABLE);
        //TIM_CtrlPWMOutputs(TIM2, ENABLE);
}

void OHM_Chk_Timer_Init(void)
{
       
        TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
        NVIC_InitTypeDef NVIC_InitStructure;
       
        RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM16, ENABLE);
       
        NVIC_InitStructure.NVIC_IRQChannel = TIM16_IRQn;
        NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
        NVIC_InitStructure.NVIC_IRQChannelPriority = 0x03;
        NVIC_Init(&NVIC_InitStructure);
       
        TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
        TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
        TIM_TimeBaseStructure.TIM_Period = 50; //50ms
        TIM_TimeBaseStructure.TIM_Prescaler = 47999; //分频，1ms计数一次
        TIM_TimeBaseStructure.TIM_RepetitionCounter = 0x03;
        TIM_TimeBaseInit(TIM16, &TIM_TimeBaseStructure);
       
        TIM_ClearITPendingBit(TIM16, TIM_IT_Update);
        TIM_ITConfig(TIM16, TIM_IT_Update, ENABLE);
        TIM_Cmd(TIM16, ENABLE);
}

void OHM_Init(void)
{
        OHM_GPIO_Init();
        OHM_TIM_PWM_Init();
        OHM_Chk_Timer_Init();
}

void OHM_Start(void)
{
        TIM_Cmd(TIM2, ENABLE);
        TIM_CtrlPWMOutputs(TIM2, ENABLE);
        GPIO_SetBits(GPIOB, GPIO_Pin_14);
}

void OHM_Stop(void)
{
        GPIO_ResetBits(GPIOB, GPIO_Pin_14);
        TIM_CtrlPWMOutputs(TIM2, DISABLE);
        TIM_Cmd(TIM2, DISABLE);
}

OLED变暗怎么感觉像是电流不够造成的，系统复位重启感觉像是电压不稳，造成的。会不会是你的电路板有问题？

怀疑PWM输出有问题的话，可以把输出线切断看看

我把uint32_t ohm_freq = 238000;改成uint32_t ohm_freq = 90000；就可以正常的了，不过还没有理解清楚是什么原因。