MIC2843

High-Efficiency 6-Channel

Linear WLED Driver with

Ultra-Fast PWM™ Control

Ultra Fast PWM is a trademark of Micrel, Inc.

MLF and MicroLeadFrame are registered trademark Amkor Technology Inc.

Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (

General Description

The MIC2843 is a high-efficiency linear white LED (WLED)

driver designed to drive up to six WLEDs, greatly

extending battery life for portable display backlighting,

keypad backlighting, and camera flash in mobile devices.

The MIC2843 provides the highest possible efficiency as

this architecture has no switching losses present in

traditional charge pumps or inductive boost circuits. The

MIC2843 provides six linear drivers which maintain

constant current for up to six WLEDs. It features a typical

dropout of less than 40mV at 20mA. This allows the

WLEDs to be driven directly from the battery eliminating

switching noise/losses present with the use of boost

circuitry.

The six channels are matched better than ±3% typical,

ensuring uniform display illumination under all conditions.

The brightness is controlled through an Ultra Fast PWM™

interface operating down to less than 1% duty cycle.

The MIC2843 is available in the 2mm x 2mm 10-pin Thin

MLF

of

−40°C to +125°C.

Datasheets and support documentation can be found on

Micrel’s web site at: www.micrel.com.

Features

• High efficiency (no voltage boost losses)

• Ultra Fast PWM™ control (200Hz to 500kHz)

• Input voltage range: 3.0V to 5.5V

• Dropout of less than 40mV at 20mA

• Matching better than ±3% (typical)

• Current accuracy better than ±1.5% (typical)

• Maintains proper regulation regardless of how many

channels are utilized

Applications

• Mobile handsets

• Digital cameras

• Portable media/MP3 players

• Portable navigation devices (GPS)

• Portable applications

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Typical Application

LCD Display Backlight with Six WLEDs

High Current Flash Driver

November 2010

M9999-110810-B