Description

       The AT381 is a single cell LED driver designed for applications where step-up voltage conversion from a very low input voltage is required. These applications mainly operate from 1.5V or 1.2V cells. The IC generates constant current pulses that are ideal for driving single or multiple LEDs over a wide range of operating voltages.

      The AT381 uses a PFM control technique to drive an internal switching transistor which exhibits a low saturation resistance. This ensures high efficiency, even for input voltages as low as 1V.

       The IC can start up under full load and operates down to an input voltage of only 0.9V.

       The AT381 is offered in the space saving SOT23 package or in die form, offering an excellent cost vs performance solution for single cell LED driving applications.

Features

• 85% Efficiency

• User adjustable output current

• Single cell operation (0.9V minimum)

• Low saturation voltage switching transistor

• SOT23-3 package

• Available also in Die form

• Simple Application circuit

• Applications

• LED flashlights and torches

• LED backlights

  White LED driver