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GND

V

IN

SWITCH

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KTT (TO-263) PACKAGE

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DESCRIPTION/ORDERING INFORMATION

TL3577

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

• 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

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.