| 摘要 |
PROBLEM TO BE SOLVED: To provide an electronic equipment which can suppress the overhead caused by the switchover of a control system and can keep a switching regulator in high efficiency within a wide load current range. SOLUTION: This electronic equipment is provided with a load circuit 44 which outputs a rectification system switching signal S45 to instruct a switching regulator 41 to operate in PWW control and synchronous rectification system in active mode, and outputs a rectification system switching signal S45 to instruct the switching regulator 41 to operate in diode rectification system in standby mode; and the above-mentioned switching regulator 41 which includes a control circuit 419 for judging whether to drive it in synchronous rectification system or to drive it in diode rectification system according to the instruction of the rectification system switching signal S45, outputting control signals CTL1 and CTL2 to driver circuits 420 and 421 according to the judged rectification system, and performing the drive control of a p-channel switching transistor 411 and an n-channel switching transistor 412. COPYRIGHT: (C)2004,JPO
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