| 摘要 |
PROBLEM TO BE SOLVED: To bring an output voltage of a DC-DC converter into accurate coincidence with a target voltage. SOLUTION: In the DC-DC converter, an inductor 6 stores and discharges energy according to the on/off-control of a main switch element 10. When the inductor 6 discharges the energy, if a sub-switch element 12 is in an on-state, a current flows to the rear stage circuit of the sub-switch element 12, and the output voltage V01 is raised. The sub-switch element 12 includes a P-channel MOS transistor. A sub-switch control circuit 18 outputs a control signal VCT1 to the sub-switch element 12. A level shifter 19 receives the supply of the output side potential VP of the inductor 6, outputs the potential VP when the control signal VCT1 is in an L-level as a control signal VG1 applied to the gate of the sub-switch element 12 and outputs potential (VP-VM) lower than the potential VP when the control signal VCT1 is in an H-level. COPYRIGHT: (C)2005,JPO&NCIPI
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