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PT4102
Step-up White LED Driver
GENERAL DESCRIPTION
The PT4102 is a step-up DC/DC converter designed for driving up to 8 white LEDs in series from a single cell Lithium Ion battery with constant current. Because it directly regulates output current, the PT4102 is ideal for driving light emitting diodes (LEDs) whose light intensity is proportional to the current passing through them, not the voltage across their terminals. A single external resistor sets LED current between 5mA and 20mA, which can then be easily adjusted using either a DC voltage or a pulse width modulated (PWM) signal. The PT4102 switches at 1.2MHz, allowing the uses of tiny external components. The output capacitor can be as small as 0.22uF. Its low 88/104mV feedback voltage reduces power loss and improves efficiency.
PT4102 Datasheet
