A NON-ISOLATING SWITCH DC-DC POWER SUPPLY MODULE, A POWER SUPPLY DEVICE, AND A COMMUNICATION DEVICE

摘要

A non-isolating switch DC-DC power supply module comprises a regulated-voltage conversion circuit (200) that includes a pair of coupled transistors (201,202), and a PWM generator (100) that outputs a pair of PWM signals for controlling the pair of transistors to switch selectively in ON and OFF states. At least one pre-regulated-voltage conversion circuit (300) is connected between power terminals of the power supply module and the regulated-voltage conversion circuit so that the input voltage (V<SUB>DD</SUB>) of the power supply module is stepped down in a pre-stage under control of the corresponding PWM signals outputted by the PWM generator.