| 摘要 |
The present invention relates to a zero crossing detection circuit of AC power which detects zero crossing by converting inputted AC power into a digital signal using a hardware circuit. Especially, in a power converter which performs full-wave rectification for inputted AC power by a bridge rectifier circuit and supplies the AC power to a load, a zero crossing detection circuit of the inputted AC power comprises a diode branching AC power in parallel and half-wave rectifying the AC power; a first resistor dropping the voltage of the half-wave rectified signal by the diode; and a PWM converter receiving the voltage-dropped signal by the first resistor and outputting the signal into a PWM signal. The present invention converts AC power into a digital PWM signal in the power converter using AC power and outputs the digital PWM signal to an MCU, thereby reducing the load of the MCU. |
