| 摘要 |
PROBLEM TO BE SOLVED: To provide an inexpensive and compact switching power supply circuit having characteristics same as conventional DC power supply circuits. SOLUTION: In this RCC type switching power supply circuit, a flyback transformer 62 is provided with a sensing coil 66 magnetically dense-coupled to an output coil 64. The sensing coil 66 is connected to a timing capacitor 55 through a Zener diode 56. The difference between the detected voltage detected as a secondary side DC voltage by rectifying and smoothing AC voltage outputted from the sensing coil 66 and the reference voltage of the Zener diode 56 is supplied to the timing capacitor 55 to change charge and discharge time and also change the timing of switching a second switching element 54, thereby controlling the switching time of a first switching element 60. COPYRIGHT: (C)2009,JPO&INPIT
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