LM1577, LM2577
www.ti.com
SNOS658D – JUNE 1999 – REVISED APRIL 2013
LM1577/LM2577 SIMPLE SWITCHER® Step-Up Voltage Reg...
LM1577, LM2577
www.ti.com
SNOS658D – JUNE 1999 – REVISED APRIL 2013
LM1577/LM2577 SIMPLE SWITCHER® Step-Up Voltage
Regulator
Check for Samples: LM1577, LM2577
FEATURES
1
23 Requires Few External Components
NPN Output Switches 3.0A, can Stand off 65V Wide Input Voltage Range: 3.5V to 40V Current-mode Operation for Improved
Transient Response, Line Regulation, and Current Limit 52 kHz Internal Oscillator Soft-start Function Reduces In-rush Current During Start-up Output Switch Protected by Current Limit, Under-voltage Lockout, and Thermal Shutdown
TYPICAL APPLICATIONS
Simple Boost
Regulator Flyback and Forward
Regulators Multiple-output
Regulator
DESCRIPTION
The 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. Listed in this data sheet are a family of standard inductors and flyback transformers designed to work with these switching
regulators.
Included on the chip is a 3.0A
NPN switch and its associated protection circuitry, consisting of current and thermal limiting, and undervoltage lockout. Other features include a 52 kHz fixed-frequency oscillator that requires no external components, a soft start mode to reduce in-rush current du...