The MC44608 is a high performance voltage mode controller designed for off−line converters. This high voltage circuit that integrates the start−up current source and the oscillator capacitor, requires few external components while offering a high flexibility and reliability. The device also features a very high efficiency stand−by management consisting of an effective Pulsed Mode operation. This technique enables the reduction of the stand−by power consumption to
approximately 1.0 W while delivering 300 mW in a 150 W SMPS.

•Integrated Start−Up Current Source
•Lossless Off−Line Start−Up
•Direct Off−Line Operation
•Fast Start−Up
General Features
•Flexibility
•Duty Cycle Control
•Undervoltage Lockout with Hysteresis
•On Chip Oscillator Switching Frequency 40, 75, or 100 kHz
•Secondary Control with Few External Components