SWITCHING POWER SUPPLY UNIT

摘要

A comparator (110) outputs a first determination reference signal (Vcmp) on the basis of a sawtooth signal (Vchp) whose level varies at a fixed period and a detected voltage signal (Vo). An inverter (113) outputs a second determination reference signal (Vcmp') by inverting the first determination reference signal (Vcmp). A comparator (111) outputs a first switching determining signal (Vtr1) from a monitor signal (Vm) and a threshold (V1), and a comparator (112) outputs a second switching determining signal (Vtr2) from the monitor signal (Vm) and a threshold (V2). An AND circuit (114) outputs a first switching control signal (Vgs1) from the first determination reference signal (Vcmp) and the first switching determining signal (Vtr1), and an AND circuit (115) outputs a second switching control signal (Vgs2) from the second determination reference signal (Vcmp) and the second switching determining signal (Vtr2).