The MIC2841A is a high efficiency White LED (WLED) driver designed to drive up to four WLEDs, greatly extending battery life for portable display backlighting, keypad backlighting and camera flash in mobile devices. The MIC2841A provides the highest possible efficiency as this architecture has no switching losses present in traditional charge pumps or inductive boost circuits. The MIC2841A provides four linear driver channels which maintain constant current for up to four WLEDs. It features a typical dropout of 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.
The MIC2841A features Dynamic Average Matching™ (DAM™) which is specifically designed to provide optimum matching across all WLEDs. The four channels are matched better than ±1.5% typical, ensuring 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 MIC2841A operates over a junction temperature range of -40°C to +125°C.
High efficiency (no voltage boost losses)
Dynamic Average Matching™ (DAM™)
Ultra Fast PWM™ control (200Hz to 500kHz)
Input voltage range: 3.0V to 5.5V
Dropout of 40mV at 20mA
Matching better than ±1.5% (typical)
Current accuracy better than ±1.5% (typical)
Maintains proper regulation regardless of how many channels are utilized