MIC3263

Six-Channel WLED Driver for

Backlighting Applications with

Flicker-Free Dimming

MLF is a registered trademark of Micrel, Inc.

January 2010

M9999-012110

can be set to a

ed to 16

frequency from 400 KHz to 1.8 MHz to a

sizes. The 6V to 40V wide input voltage

allows direct operation from 6V or high

batteries commonly found in notebook compute

range of

−40°C to +125°C.

Data sheets and support documentation can be found on

General Description

The MIC3263 is a high-efficiency Pulse Width

(PWM) boost switching regulator that is op

constant-current WLED d

Modulation

timized for

lications.

river backlighting ap

The MIC3263 drives six channels of up to ten

channel. Each channel is matched in current to

for constant brightness across the screen a

programmed from 15mA to 30mA.

The MIC3263 provides a very flexible dimm

scheme with better accuracy and noise imm

dimming frequency

p

WLEDs per

within ±3%

nd can be

ing control

unity. The

ny value between

100Hz and 20kHz by an external resistor. T

ratio is determined by the duty cycle of a dim

control input signal and can be set to one of 16

he dimming

ming ratio

levels with

a minimum ratio of 1%.The LED dimming curre

an external resistor to allow programming of

between 15mA and 30mA.

The dimming ratio of the MIC3263 is fix

nt is set by

LED current

log levels

to better match the sensitivity of the human e

the dimming levels has hysteresis to avo

between levels and a

ye. Each of

id skipping

llow for high noise immun

The MIC3263 has a programmable PW

ity.

M switching

llow small inductor

range of MIC3263

cell count Li-Ion

rs.

The MIC3263 is available in a low-profile 24-pin 4mm x

4mm MLF® package and has a junction temperature

.

nge

white LEDs

from 15mA to 30mA

ith open and short LEDs

og levels sets the dimming ratio

the jitter from the dimming

control input signal and eliminates dimming flicker

control

rrent matching ±3%

ED current setting ±2%

ing frequency from 400kHz to

High efficiency up to 90%

Low (<40μA) shutdown current over temperature

rature protection

mmable over-voltage protection

°C to +125°C junction temperature range

ilable in 24-pin 4mm x 4mm MLF® package

ons

• White LED driver for backlighting

• LCD Panels and Monitors

• Multimedia players

• Navigation equipment

• Gaming systems

• Video poker

• Slot machines

_________________________________________________________________________________________________________________________

Features

• 6V to 40V wide input voltage ra

• Drives 6 channels of up to 10

• Programmable WLED current

• Highly reliable operation w

• Accurate 16 dimming l

from 1% to 100%

• Flicker-Free Dimming filters

• Allows external dimming

LED channel cu

• Accurate

• Accurate initial L

• Programmable switch

1.8MHz

•

•

• Over tempe

• Progra

• −40

• Ava

Applicati

• Notebooks