24V恒流驱动LED模块电路

备注：驱动代码参考

// 恒流输出设置（PA8初始化为推挽输出）
#define SetBackLampOn( )    { GPIOA->BRR = GPIO_Pin_8; }
#define SetBackLampOff( )    { GPIOA->BSRR = GPIO_Pin_8; }

//PB15 亮度调节，Timer1初始化PWM输出，用于产生100Hz载波驱动灯带。

void TIM1_Init_PWM_100Hz( void )

{

TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;

//相关寄存器恢复默认值

RCC_APB2PeriphResetCmd(RCC_APB1Periph_TIM1, ENABLE);

RCC_APB2PeriphResetCmd(RCC_APB1Periph_TIM1, DISABLE);

 

TIM_TimeBaseStructure.TIM_Prescaler = ( 72 * 100 - 1 );//预分频到10K

TIM_TimeBaseStructure.TIM_Period = 100; //计数周期 100

TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;//不分频 

TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;//向上计数

TIM_TimeBaseStructure.TIM_RepetitionCounter = 0; 

TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);

   

// 通道 3，输出 PWM波形

TIM1->CCMR1 = 0x0000; 

TIM1->CCMR2 = 0x006C; 

 

TIM1->CCR1 = TIM_TimeBaseStructure.TIM_Period / 2;  // 占空比 1/2.

 

TIM1->CCER = 0x0000;// OC1,2,3 is not active

 

TIM1->CR1 |= TIM_CR1_ARPE; //使能 timer3 重载计时器

TIM1->CR1 |= TIM_CR1_CEN; // timer3 开始计数.

}

TIM1->CCER = 0x01;//一通道使能

TIM1->CCER = 0x00;//一通道失能

//电流设计范围 12%~78% 取77mA~498mA

//实测1-10：123mA,167mA,207mA,255mA,296mA;

                     342mA,390mA,432mA,479mA,527mA;

void SetBackLightLevel( U8 Level )
{
    U32 Duty;
    
    SetBackLampOff( );// 关闭输出
    if( Level == 0 ){
        return;
    }
    if( Level > 10 ){
        Level = 10;
    }
    Duty = TIM_BACK_LAMP_PERIOD * 20UL + TIM_BACK_LAMP_PERIOD * 60UL * ( 10UL - (U32)Level ) / 10UL;
    Duty /= 100UL;
    TIM1->CCR3 = (U16)Duty;
    delay_us( 5000 );
    SetBackLampOn( );// 重新开启
}