AN4374 Datasheet, PDF (1/25 Pages) STMicroelectronics – The LED1642GW and ALED1642GW start-up guide

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
SDO PWCLK
SDI
CLK
LE
VDD
GND
Control Logic &
Data Registers
UVLO
& POR
PWM
counter
Error
detection
OUT0
OUT1
OUT2
Configuration
register
Thermal
shutdown
R-EXT
Current
Ref.
Current gain
adjustment
Channel driver
Timing control
Turn ON/OFF
Gradual delay
OUT14
OUT15
AM16850v1
November 2014
DocID025366 Rev 2
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