Multi-output power supply and electronic device using them

Abstract

For controlling DC-DC converters conforming to voltage mode control system and current mode control system, in multi-output power supply, first converter sectionis configured that first detection circuitoutputs first control signal, that first oscillation circuitoutputs first triangular wave signal and clock signal, and that first pulse-width modulation circuitdrives first switch by comparing first control signal with first triangular wave signal. Second converter sectionis configured that second detection circuitoutputs second control signal, that second oscillation circuitoutputs second triangular wave signal synchronized with clock signal, that current detection circuitoutputs current signal of second inductor, and that second pulse-width modulation circuitturns ON second switch in synchronization with clock signal and turns OFF second switch by calculating or comparing second control signal, the second triangular wave signal and current signal.