High efficiency power supply circuit and electronic device incorporating the high efficiency power supply circuit

摘要

An electric power supply circuit includes a first switching element that turns on or off according to an external signal; an inductor capacitor circuit provided between the power supply and the load that charges or discharges electric power provided by the power supply according to the on or off state of the first switching element; a rectifier diode provided between the first switching element and the ground; a second switching element provided in parallel with the rectifier diode that turns on or off synchronously with the first switching element; and a depletion transistor that detects a direction of a current flowing through the inductor capacitor circuit based on a voltage detected across the second switching element to generate a detection result, and causes the second switching element to turn on or off according to the detection result.