SDIM*

GND

UDIM

TPS92641

DAP

VIN

LED+

LED-

R2

R3

R1

C1

R4

R8

R7

C6

C8

R5

R6

C7

D2

Q1

Q2

Q3*

LED

LOAD

L1

C5

C2

C4

C3

D1

R10

R9

HG

SW

BOOT

VCC

LG

CS

GND

SDRV

VIN

RON

UDIM

VOUT

VREF

IADJ

COMP

SDIM

TPS92640

TPS92641

www.ti.com

SNVS902 – NOVEMBER 2012

TPS92640 / TPS92641 Synchronous Buck Controllers for Precision Dimming LED Drivers

Check for Samples: TPS92640, TPS92641

1

FEATURES

DESCRIPTION

The TPS92640/41 are high voltage, synchronous

2

•

NFET controllers for buck current regulators. Output

•

2

current regulation is based on valley current-mode

•

Adjustable LED Current Sense voltage

control with a constant on-timer. This control method

eases

the

design

of

loop

compensation.

The

•

Input UVLO and output OVP

TPS92640/41

includes

a

high-voltage

start-up

•

Various dimming modes

regulator that operates over a wide input range of 7V

–

500:1 Analog Dimming

to 85V. The PWM controller is designed for high

speed capability including an oscillator frequency

–

2500:1 Standard PWM dimming

range up to 1.0 MHz. The TPS92640/41 is optimized

–

20000:1 Shunt FET PWM dimming

to give superior dimming performance with both

•

Shunt Dimming MOSFET gate driver

analog and PWM dimming. Both devices include an

error amplifier, precision reference, thermal shutdown

•

Programmable switching frequency

and low power shutdown mode. Additionally, the

•

Precision Voltage Reference

TPS92641 provides shunt FET dimming capability.

•

Low Power Shutdown Mode and Thermal

Shutdown

APPLICATIONS

•

LED Driver / Constant Current Regulator

•

Automotive LED Drivers

•

General LED Illumination

TYPICAL APPLICATION DIAGRAM

1

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.

2

All trademarks are the property of their respective owners.

PRODUCT PREVIEW information concerns products in the

Copyright © 2012, Texas Instruments Incorporated

formative or design phase of development. Characteristic data and

other specifications are design goals. Texas Instruments reserves

the right to change or discontinue these products without notice.