November 2014

DocID025366 Rev 2

1/25

25

AN4374

Application note

The LED1642GW and ALED1642GW start-up guide

Fabio Occhipinti

Introduction

The use of LEDs in applications like displays, information and advertising panels, signs,

traffic signals, automotive lighting and architectural lighting is becoming more and more

popular. The LED array drivers, with accurate constant current regulation and embedded

serial interface, are the solution suitable for the above mentioned applications. This

document provides an overview about the LED1642GW LED array driver and the

ALED1642GW (automotive grade version). The first part of this document is focused on the

device startup, as well as the main communication key explanation for an easy use of this

product. The last part of this document gives some general guidelines relative to the

application dimensioning and the PCB design.

Figure 1. LED1642GW and ALED1642GW block diagram

UVLO

& POR

Configuration

register

Channel driver

Timing control

Turn ON/OFF

Gradual delay

Current gain

adjustment

SDI

CLK

LE

GND

R-EXT

SDO

OUT0

OUT1

OUT2

OUT14

OUT15

PWM

counter

PWCLK

Thermal

shutdown

Current

Ref.

Control Logic &

Data Registers

Error

detection

AM16850v1

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