MIC4812 
High Current 6 Channel Linear WLED 
Driver with DAM™ and Ultra Fast 
PWM™ Control 
 
 
 
 
 
Ultra Fast PWM, DAM and Dynamic Average Matching are  trademark of Micrel, Inc.
 
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
General Description 
The  MIC4812  is  a  high  efficiency  linear  White  LED 
(WLED)  driver  designed  to  drive  up  to  six  high  current 
WLEDs  for  signage  lighting.  The  MIC4812  provides  the 
highest  possible  efficiency  as  this  architecture  has  no 
switching  losses  present  in  traditional  charge  pumps  or 
inductive  boost  circuits.  The  MIC4812  provides  six  linear 
drivers  which  maintain  constant  current  for  up  to  six 
WLEDs. It features a typical dropout of 190mV at 100mA.  
The  MIC4812  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  MIC4812  is  available  in  an  10-pin  MSOP  ePad 
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 100mA per channel 
•  Programmable LED current with external resistor  
•  Dropout of 190mV at 100mA 
•  Matching better than ±1% (typical)  
•  Current Accuracy better than ±1% (typical) 
•  Maintains proper regulation regardless of how many 
channels are utilized 
•  10-pin MSOP with ePad package 
Applications 
•  Billboard displays 
•  Marquee displays 
•  Instrument displays 
•  LCD display modules 
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Typical Application 
 
 
High Current Lighting (Six WLEDs) 
  
April 2011  M9999-041911-B