| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a self-excited DC/DC converter with improved efficiency and a drive circuit thereof. <P>SOLUTION: This drive circuit 100 controls turning-on and -off a switching transistor Tr1 of the self-excited DC/DC converter. A first resistor R1 is provided on a path of a current running through a primary coil of a transformer 10 connected to the switching transistor Tr1 and one end thereof is grounded. A second resistor R2 is arranged on the path of the current flowing in the secondary coil of the transformer 10, and its one end is grounded. When a first detected voltage Vx1 exceeds a first threshold voltage Vth1, a switching control section 30 turns off the switching transistor Tr1, and turns off the switching transistor Tr1 when at a lapse of a predetermined delay timeτafter a second detected voltage Vx2 exceeds a second threshold voltage. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
