
Micrel
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.
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
• Available in a 2mm x 2mm 10-pin Thin MLF® package
APPLICATIONs
• Mobile handsets
• Digital cameras
• Portable media/MP3 players
• Portable navigation devices (GPS)
• Portable applications