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FEATURES
APPLICATIONS
1
2
3
4
5
GND
FEEDBACK
GND
V
IN
SWITCH
COMP
KTT (TO-263) PACKAGE
(TOP VIEW)
DESCRIPTION/ORDERING INFORMATION
100-kHz CURRENT-MODE SIMPLE STEP-UP/FLYBACK SWITCHING REGULATOR
SLVS633 – OCTOBER 2006
Simple Boost Converter
Few External Components Required (As Few
As Six)
Flyback Converters, Single/Multiple Outputs
SEPIC Converter With V
IN Higher or Lower
Current Limit, Undervoltage Lockout, and
Than Output Voltage
Thermal Shutdown
Transformer-Coupled Forward Converters
Wide Input Voltage Range: 3 V to 40 V
100-kHz Internal Oscillator Allows for Use of
Small Magnetics
Current-Mode Operation for Faster Transient
Response, Line Regulation, and
Cycle-by-Cycle Current Limiting
Soft-Start Capability Provides Controlled
Startup Current
Improved Replacement for LM2577 Series
The TL3577 series are easy-to-use devices that incorporate all the active circuitry required to implement either
step-up (boost), flyback, forward converter, or SEPIC converter switching regulators. The internal 3-A 65-V
switch allows the TL3577 to provide an output voltage of up to 60 V as a simple boost regulator; higher output
voltages can be achieved with the TL3577 configured as a flyback or forward converter.
Requiring few external components, The TL3577 features a wide input voltage range of 3 V to 40 V and offers
an adjustable output voltage. Basic protection features include undervoltage lockout, thermal protection, and soft
start, which is provided to reduce input current during startup. Current-mode control provides cycle-by-cycle
current limiting, as well as faster line and load regulation. The internal 100-kHz oscillator allows for use of
smaller magnetics and filter components, when compared with similar regulators running at 52 kHz. A standard
series of inductors and capacitors optimized for use with these regulators is available from several
manufacturers and are listed in this data sheet.
The TL3577 is characterized for operation over the virtual junction temperature range of –40
°C to 125°C.
ORDERING INFORMATION
VO
TJ
PACKAGE(1)
ORDERABLE PART NUMBER
TOP-SIDE MARKING
(NOM)
–40
°C to 125°C
ADJ
TO-263 – KTT
Reel of 500
TL3577-ADJIKTTR
TL3577ADJI
(1)
Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Copyright 2006, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.