JY02是使用VR端電壓來調速的,電壓越低,轉速越低,電壓越高,轉速越高,調節的電壓範圍是0-5V,可是我們如果使用3.3V的單片機來控制轉速的話,就不能調節到最高轉速了,這時,我們可以使用單片機的PWM來調節,電路如下:
其中VRI來控制JY02的VR端,VR_MCU接單片機的PWM輸出,輸出極性使用低電平,代碼如下:
void TIM2_PWM_Init(u16 arr,u16 psc)
{
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
TIM_TimeBaseStructure.TIM_Period = arr;
TIM_TimeBaseStructure.TIM_Prescaler =psc;
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
TIM_OC2Init(TIM2, &TIM_OCInitStructure);
TIM_OC2PreloadConfig(TIM2, TIM_OCPreload_Enable);
TIM_Cmd(TIM2, ENABLE);
}
主函數來調用:
TIM2_PWM_Init(99,71);
TIM_SetCompare2(TIM2,FanSpeed);
FanSpeed是要調節的電機轉速,我使用的電機調節範圍是15-100,太小的話,電機會啓動不起來。