| 摘要 |
<P>PROBLEM TO BE SOLVED: To further elevate the efficiency of a voltage converter which can selectively obtain a voltage level nonconversion mode, a step-down mode, and a step-up mode. <P>SOLUTION: A series circuit 2 of first and second switches Q1 and Q2, a series circuit of third and fourth switches Q3 and Q4, a series circuit of fifth and sixth switches Q5 and Q6, and a capacitor C are connected in parallel with one another. The first to sixth switches Q1-Q6 are controlled so that the nonconversion mode of equalizing output voltage V0 with input AC voltage Vin, the step-down mode of lowering V0 than Vin, and the step-up mode of elevating V0 than Vin, can be obtained. Bias voltage Vs is set higher than a limiter value V<SB>L</SB>so as to enlarge the range of inhibiting the high frequency ON/OFF action of the first, second, fifth, and sixth switches Q1, Q2, Q5, and Q6. <P>COPYRIGHT: (C)2004,JPO |
