STLD20D - ST Microelectronics

STLD20D WHITE LED POWER SUPPLY

The STLD20D is a constant switching frequency boost regulator with specific features to supply up to 4 white LEDs in series. A stable LED current regulation, from 2.8V to 4.2V, is achieved by sensing the LED current through a low ohmic shunt resistor RLED (see figure 1). The device also includes a supply rejection circuit that prevent any kind of flickering .

Features

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■ APPLICATION
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■ High efficiency above 80% Can drive up to 4 LEDs in series from 2.8V supply Constant LED current regulation Integrated LED disconnect switch that cuts the LEDs branch in shutdown mode Constant switching frequency Stable current regulation across the total input voltage range Supply voltage rejection Inherent soft start by limiting the peak inductor current Peak inductor current adjustability (STLD20DC8 only) Shutdown pin with possibility of PWM dimming control Over voltage and over temperature protection with automatic restart Low shutdown cu.