DESCRIPTION

· The MIC3291 is a PWM switching boost regulator optimized for constant current white LED (WLED) driver applications.

· It features an internal Schottky diode, requiring only four external components for an efficient DC/DC solution.

· The device offers a single-wire digital interface for linear dimming control over 16 steps.

· It supports a 2.5V to 6.5V input voltage range, suitable for single-cell Li-Ion and 3 to 4 cell NiCad/NiMH/Alkaline batteries.

· The MIC3291 operates at a constant frequency of 1.2MHz PWM, reducing switching noise and ripple.

· It is available in Thin SOT23 6-pin and 2mm × 2mm MLF® 8-pin packages with a junction temperature range of –40°C to +125°C.

FEATURES

· Single-wire interface for 16-level linear brightness and shutdown control.

· 18V / 25V OVP options supporting up to four and six WLEDs.

· Startup at any of the 16 brightness levels.

· Internal Schottky diode for efficient operation.

· 2.5V to 6.5V input voltage range.

· 1.2MHz PWM operation for reduced component size and noise.

· Over 500mA switch current capability.

· 250mV reference voltage for high efficiency and accuracy.

· ±5% LED current accuracy.

· Less than 1µA shutdown current for battery life preservation.

· UVLO and over-temperature protection.

· Available in Thin SOT23-6L and 2mm × 2mm leadless MLF® packages.

· Junction temperature range from –40°C to +125°C.

APPLICATIONS

· Mobile handsets.

· LCD handset backlighting.

· Digital cameras.

· Portable media players/MP3 players.

· Portable applications requiring efficient LED driving solutions.