| 摘要 |
This circuit comprises a phase-lock stage receiving at the input a reference signal and the synchronism signal EN and generating at the output a triangular signal in phase correlation with the synchronism signal, a rectangular waveform generator receiving at the input the triangular signal and supplying at the output a rectangular signal, a drive element receiving the rectangular signal and generating a periodic control signal, as well as a phase comparator receiving at the input the triangular signal and the control signal, as well as a further reference signal and generating at the output an error signal correlated with the phase shift of the drive element and fed to the rectangular waveform generator. The reference signal fed to the phase-lock stage or to the phase comparator can be suitably varied within preset limits by an external potentiometer. |
