1results about How to "Eliminate howling" patented technology

The application discloses a kind of full-automatic hardware intervention method and device of pulse width modulation signal, method includes: S1, the extreme point of triangular carrier signal is set as absolute center;S2, by bottom hardware logic gate, an absolute symmetrical time execution window is automatically demarcated to two sides of absolute center;S3, when the count value enters time execution window, bottom hardware logic gate is configured to ignore current main duty cycle setting and carry out forced operation, for the level of PWM output channel is set or cleared;S4, carry out hardware level automatic flip: in successive PWM period, carry out hardware level automatic flip, for in fundamental center seamless superimposed alternating high-frequency square wave signal.The application introduces independent physical execution window and polarity automatic flip mechanism in the bottom digital logic of microcontroller timer, realizes high-frequency alternating voltage injection and accurate waveform clipping under zero CPU computing power consumption, completely eliminates phase distortion and risk of magnetic bias.