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PT4205
30V, 1.2A Step-down HB LED Driver
GENERAL DESCRIPTION
The PT4205 is a continuous conduction mode inductive step-down converter, designed for driving single or multiple serie connected LEDs efficiently from a voltage source higher than the total LED chain voltage. The device operates from an input supply between 5V and 30V and provides an externally adjustable output current of up to 1.2A. Depending upon the supply voltage and external components, the PT4205can provide more than tens of watts of output power. The PT4205 includes the power switch and a high-side output current sensing circuit, which uses an external resistor to set the nominal average output current, and a dedicated DIM input accepts either a DC voltage or a wide range of pulsed dimming. Applying a voltage of 0.