MIC4834

MLF and MicroLead Frame are registered trademark of Amkor Technologies

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

October 2008

M9999-100808-A

General Description

The MIC4834 is a low noise dual Electroluminescent (EL)

Panel driver used in backlighting applications. The

MIC4834 converts a low DC voltage to a high DC voltage

using a boost converter and then alternates the high DC

voltage across the EL panels using an H-bridge. The

MIC4834 incorporates internal wave-shaping circuitry

specifically designed to reduce audible noise emitted by

EL panels. With only one inductor the MIC4834 can drive

two outputs and requires a minimum number of passive

components. It features an operating input voltage range

of 2.3V to 5.8V, making it suitable for 1-cell Li-ion and 2- or

3-cell alkaline/NiCad/NiMH battery applications.

The MIC4834 features separate oscillators for the boost

and H-bridge stages. The boost frequency may be

adjusted with an external resistor to optimize efficiency

and brightness. The H-bridge frequency is internally preset

to 225Hz, to reduce the number of external components

and layout space.

The MIC4834 is available in 10 pin 3mmx3mm MLF

®

package as well as MSOP-10L, and has an operating

junction temperature range of –40

°C to +125°C.

Features

•

Drives two EL panels, up to 3 in

brightness

•

•

2.3V to 5.8V DC input voltage

•

Wave-shaping circuit to reduce audible noise

•

Adjustable boost converter frequency

•

Single inductor to power both panels

•

0.1µA typical shutdown current

•

Package options

−

10-pin 3mmx3mm MLF

®

−

10-pin MSOP

•

–40

Applications

•

Mobile phones

•

MP3/portable media players (PMP)

•

Clocks/ watches

•

Remote controls

•

Cordless phones

•

GPS devices

•

PDAs

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Typical Application

Low Noise Dual EL Driver