| 摘要 |
PURPOSE:To transmit a signal without extending a photo-coupler (an insulating element) even when the amount of information transferred between the secondary side and the primary side is increased by transmitting the signal by using a parallel/serial converter, the photo-coupler and a serial/parallel converter. CONSTITUTION:An A/D converter 47 converts the output voltage of a DC conversion circuit 10 into a digital signal in the fixed number of bits. A parallel/serial converter 51 converts the contents of the digital signal into a serial pulse train signal in the order of a bit array and transmits the pulse train signal. Consequently, only one insulating element such as a photo-coupler 53 insulating the signal and transmitting the signal from the secondary side to the primary side may be used. A control circuit 30 conducts control operation stabilizing output voltage on the basis of the output voltage of the DC conversion circuit 10 received by a serial/parallel converter 37, and on-off controls a switching element. |
