LM3503-44

Sw

En1

En2

Fb

Cntrl

AGND

PGND

L

22 PH

D

4.7 PF

1 PF

R1

MAIN:

2 to 5

LEDs

SUB:

2 to 5

LEDs

Logic

Voltage

Signal

Inputs

LM3503

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SNVS329D – JULY 2005 – REVISED AUGUST 2006

LM3503 Dual-Display Constant Current LED Driver with Analog Brightness Control

Check for Samples: LM3503

1

FEATURES

2

•

Drives up to 4, 6, 8 or 10 White LEDs for Dual

•

Low Profile Packages: <1 mm Height

Display Backlighting

–

10 Bump DSBGA

•

>80% Peak Efficiency

–

16 Pin WQFN

•

Output Voltage Protection Options: 16V, 25V,

35V & 44V

APPLICATIONS

•

Input Under-Voltage Protection

•

Dual Display Backlighting in Portable devices

•

Internal Soft Start Eliminates Inrush Current

•

Cellular Phones and PDAs

•

1 MHz Constant Switching Frequency

•

Analog Brightness Control

•

Wide Input Voltage Range: 2.5V to 5.5V

DESCRIPTION

The LM3503 is a white LED driver for lighting applications. For dual display backlighting applications, the

LM3503 provides a complete solution. The LM3503 contains two internal white LED current bypass FET (Field

Effect Transistor) switches. The white LED current can be adjusted with a DC voltage from a digital to analog

converter or RC filtered PWM (pulse-width-modulated) signal at the Cntrl pin.

With no external compensation, cycle-by-cycle current limit, output over-voltage protection, input under-voltage

protection, and dynamic white LED current control capability, the LM3503 offers superior performance over other

step-up white LED drivers.

Typical Application

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.

PRODUCTION DATA information is current as of publication date.

Copyright © 2005–2006, 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.