The MIC2846A is a high efficiency White LED (WLED) driver featuring two low quiescent current LDOs. It is designed to drive up to six LEDs and greatly extend battery life for portable display backlighting and keypad backlighting in mobile devices. The MIC2846A architecture provides the highest possible efficiency by eliminating switching losses present in traditional charge pumps or inductive boost circuits. With a typical dropout of 40mV at 20mA, the MIC2846A allows the LEDs to be driven directly from the battery eliminating switching noise and losses present with the use of boost circuitry.

The MIC2846A features Dynamic Averaged Matching? (DAM?) which is specifically designed to get the optimum matching despite process variations. This ensures a typical matching of ±1.5% between all six LED channels. The LED brightness is preset by an external resistor and can be dimmed using a single-wire digital control. The digital interface takes commands from digital programming pulses to change the brightness in a logarithmic scale similar to the eye's perception of brightness. The single-wire digital brightness control is divided into two modes of operation; full brightness mode or battery saving mode for a total of 49 brightness steps.

The MIC2846A also features two independently enabled low quiescent current LDOs. Each LDO offers ±3% accuracy over temperature, low dropout voltage (150mV @ 150mA), and low ground current under all load conditions (typically 35µA). Both LDOs can be turned off to draw virtually no current.

The MIC2846A is available in the 2.5mm x 2.5mm 14-pin Thin MLF??leadless package with a junction temperature range of -40°C to +125°C.

  High efficiency (no voltage boost losses)

  Dynamic Average Matching? (DAM?)

  Single wire digital control

  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