| 摘要 |
PROBLEM TO BE SOLVED: To provide a multiple-power supply circuit and a multiple-power supply method by which multiple-power supply is generated efficiently, and power consumption is reduced. SOLUTION: A supply voltage Vbb0 is output from a DC-DC converter 2. Output transistors M1, M2 of linear regulators LDO1, LDO2 are connected in series to a power supply path between a resistor element R1 and the DC-DC converter 2, namely a bias current path is made common between the linear regulators LDO1 and LDO2, and the path is constituted to be one. Supply voltages Vbb1 and Vbb2 are generated by the linear regulators LDO1, LDO2, wherein the supply voltages are intermediate negative voltages between the supply voltage Vbb0 and a reference voltage GND with the supply voltage VbbO as a reference. A bias current consumed by the multiple-power supply circuit 1 is constituted to be constant at the bias current (i) in spite of the number of the linear regulators. COPYRIGHT: (C)2007,JPO&INPIT
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