| 摘要 |
PURPOSE:To provide an efficient switching regulator which can reduce the amount of power consumption and has a low noise. CONSTITUTION:Drive circuits 22 and 33 apply each switching signal to switching elements Q11-Q13 via the floating capacity of the switching elements Q11-Q13 and a resonance circuit. A scramble modulation circuit 40 performs scramble modulation of an error voltage according to a load RL, a mark rate judgment part 35 detects the ratio of ON/OFF sections of each switching signal of the switching elements Q11-Q13 based on the scramble modulation signal, and the drive circuit 33 regenerates the power at the side of a secondary coil L2 of a high-frequency transformer T by turning on or off the switching elements Q12 and Q13 when load is heavy and light based on the ratio. |
