| 摘要 |
PROBLEM TO BE SOLVED: To surely perform overcurrent protection operation at high speed, even if a CPU with low-cost components having low processing speed is used. SOLUTION: The switching power supply, comprising a switch circuit (DC/DC converter) 16 that performs switching operation in response to a control pulse; a digital control section 26, including a CPU 261 and performing output control of the control pulse to the switch circuit; a detection circuit 20 for detecting the overcurrent state of the switching power supply; a latching circuit 22 for holding an overcurrent detection signal from the detection circuit 20, and a gate circuit 24, inserted into the control pulse input line of the DC/DC converter and stopping input of the control pulse to the switching element Q2 in the DC/DC converter 16, when the latch circuit 22 is holding the overcurrent detection signal, wherein the digital control section 26 receives the overcurrent detection signal from the overcurrent detection circuit 20. COPYRIGHT: (C)2008,JPO&INPIT
|
