摘要 |
PROBLEM TO BE SOLVED: To prevent an overcurrent from passing through a non-insulated DC-DC converter in soft start control. SOLUTION: The non-insulated DC-DC converter inversely operates a first MOS transistor 11 and a second MOS transistor 12, and thereby performs direct- current conversion. The second MOS transistor 12 is kept off during soft start control periods wherein the on-duty time of the first MOS transistor 11 is shortened during initial phases immediately after power application and is thereafter gradually lengthened.
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