Introduction

STLD41

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Doc ID 022283 Rev 5

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Introduction

The STLD41 is a boost converter, dedicated to power and control the current of white LEDs

in an LCD backlight. The device operates at a typical constant switching frequency of 1.4

MHz. It steps an input voltage ranging from 3.0 V to 21 V up to 40 V. The output current is

dimmable by the PWM signal applied to the PWM pin.

6.1

PWM input

The light intensity can be dimmed by a signal applied to the PWM input. It is recommended

to use a signal whose frequency is between 25 kHz to 50 kHz. The maximum amplitude of

the signal is limited to 5.5 V. The minimum level of the signal must be at least 1.4 V. The