| 摘要 |
PROBLEM TO BE SOLVED: To provide a switching regulator capable of properly responding to a sharp load variation without requiring a coil inductor value determined to be needlessly small by design and to provide an electric apparatus using the switching regulator. SOLUTION: The switching regulator includes a PWM signal generating circuit 10 which generates a PWM signal G1 so that a first feedback voltage Vfb1 corresponding to an output voltage VOUT matches a first reference voltage Vref1, a PFM signal generating circuit 20 which generates a PFM signal G2 so that the first feedback voltage Vfb1 matches a second reference voltage Vref2, a load variation detecting circuit 30 which detects a load variation, and a pre-driver circuit 50 which when the load variation is not detected, arbitrarily selects and outputs either of the PWM signal G1 and the PFM signal G2 as a control signal G0 for controlling an output transistor M1, and when the load variation is detected, forcibly selects and outputs the PFM signal G2 as the control signal G0 for controlling the output transistor M1. COPYRIGHT: (C)2011,JPO&INPIT |
