National Semiconductor LM1577 Manuals

General description of LM1577/LM2577 simple switch step-up voltage regulator

LM1577/LM2577 Series SIMPLE SWITCHER® Step-Up Voltage Regulator

LM1577/LM2577 are monolithic integrated circuits that provide all of the power and control functions for step-up (boost), flyback, and forward converter switching regulators. The device is available in three different output voltage versions: 12V, 15V, and adjustable. Requiring a minimum number of external components, these regulators are cost effective, and simple to use. Features include NPN output switches, wide input voltage range, current-mode operation, 52 kHz internal oscillator, soft-start function, and output switch protection.

The LM1577/LM2577 is a simple switch regulator that provides up to 3.0A of output current. The input voltage range is 3.5V to 40V. The device features overcurrent protection, undervoltage protection, and thermal shutdown.