Patent ID: 7652456
Filing Date: 2010-01-26
Classification: H02M,Y02B

Abstract:
1. A switching regulator comprising: a first transistor and a second transistor connected in series between an input voltage and a reference voltage; an output terminal arranged to output an output voltage in accordance with a voltage appearing at a first connection point between the first and second transistors; a first control circuit arranged to output a first control signal and a second control signal for alternately turning on and off the first and second transistors, respectively, in accordance with the output voltage at the output terminal; a third transistor connected in parallel with the second transistor between the first connection point and the reference voltage, the third transistor being arranged to be controlled by the second control signal in common with the second transistor; an impedance element disposed between the third transistor and the reference voltage; a detector arranged to detect whether or not a level at a second connection point between the third transistor and the impedance element is lower than the reference voltage; and a second control circuit arranged to output a third control signal to turn off the second transistor prevailing over the second control signal when the detector cannot detect that the level at the second connection point is lower than the reference voltage.