| 摘要 |
PROBLEM TO BE SOLVED: To provide a DC power supply device which is simple in constitution and reducible in output variation even if there is a change in surrounding temperature atmosphere. SOLUTION: The DC power supply device feeds DC power to a load 43 by on/off-driving a flyback transformer 38 by an IPD 39, and controls an operation of a transistor 48 of a control circuit of the IPD 39 according to a detection voltage of a detection circuit 52 which detects a voltage corresponding to a current flowing to the load 43. The detection circuit 52 is constituted of a resistor 51 and a correction means 54 of a diode 53 which is substantially equal to the transistor 48 in temperature characteristics by using the same structure as that of the transistor 48. Even if a base-emitter voltage VBE of a transistor 18 varies due to the change of the surrounding temperature atmosphere, the detection voltage of the detection circuit 52 is changed by the diode 53, and thus the detection voltage of the detection circuit 52 is made to correspond to the base-emitter voltage VBE of the transistor 48 after the variation. COPYRIGHT: (C)2008,JPO&INPIT
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