Feedback limited duty cycle switched mode power supply.

摘要

A switched mode power supply includes a modulator (U4150) that has an input for receiving a sense signal and an output for developing a pulse modulated signal. An output switch (Q4100) is coupled to the modulator and is switched in accordance with the pulse modulated signal. A generator (D2, WS2, C5) develops a supply voltage responsive to operation of the switch. A feedback circuit (FBS) coupled between the modulator output and a modulator input limits the duty cycle of the pulse modulated signal.