MIC4811_1104 Datasheet, PDF (1/12 Pages) Micrel Semiconductor – High Current 6 Channel Linear WLED Driver with DAM™ and Ultra Fast PWM™ Control

MIC4811
High Current 6 Channel Linear WLED
Driver with DAM™ and Ultra Fast
PWM™ Control
General Description
The MIC4811 is a high efficiency linear White LED
(WLED) driver designed to drive up to six high current
WLEDs for signage lighting. The MIC4811 provides the
highest possible efficiency as this architecture has no
switching losses present in traditional charge pumps or
inductive boost circuits. The MIC4811 provides six linear
drivers which maintain constant current for up to six
WLEDs. It features a typical dropout of 100mV at 50mA.
The MIC4811 features Dynamic Average Matching™
(DAM™) which is specifically designed to provide optimum
matching across all WLEDs. The high accuracy (±1%
typical) current regulated WLED channels ensure 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 MIC4811 is available in an 10-pin MSOP package
with a junction temperature range 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
• LED current range up to 50mA per channel
• Programmable LED current with external resistor
• Dropout of 100mV at 50mA
• Matching better than ±1% (typical)
• Current Accuracy better than ±1% (typical)
• Maintains proper regulation regardless of how many
channels are utilized
• 10-pin MSOP package
Applications
• Billboard displays
• Marquee displays
• Instrument displays
• LCD display modules
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Typical Application
High Current Lighting (Six WLEDs)
Ultra Fast PWM, DAM and Dynamic Average Matching are trademark of Micrel, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
April 2011
M9999-041411-B