The A8522 is a programmable multi-output LED driver for LCD backlighting. It integrates a current-mode boost converter with internal power switch and 8 current sinks. The IC operates from 4.5 to 36 V, and is able to withstand up to 40 V load-dump conditions encountered in automotive systems.
The control loop is optimized to eliminate night flash in display backlight applications.
The I2C interface allows the user to set the LED currents individually, up to 60 mA per LED channel. Adjacent channels may be combined to drive higher-current LED strings. The PWM dimming duty cycle also is independently controlled for each LED channel. This flexibility makes the A8522 a single solution for a wide range of LED applications. Two-way communication allows fault status to be reported.
PWM dimming duty cycle also is independently controlled for each LED channel. This flexibility makes the A8522 a single solution for a wide range of LED applications, in some cases offering the ability to replace two or more LED driver ICs with a single device.
The A8522 detects and protects against a wide variety of fault conditions, and two-way communication allows fault status to be reported. It provides protection against output short and overvoltage, open or shorted diode, open or shorted LED pin, shorted boost switch or inductor, and IC overtemperature. A dual cycle-by-cycle current limit protects the internal switch against switch overcurrent. If required, the IC can drive an external PFET as an input-disconnect switch that is triggered by integrated current sense.