Single-string white LED driver IC for LCD backlighting

February 07, 2012 // By Christoph Hammerschmidt
Allegro MicroSystems Europe has announced a single-output white LED driver IC. The A8513 is designed for backlighting applications in LCD displays for automotive and consumer applications and their associated application, performance, and protection requirements.

The device, which integrates a current-mode boost converter with an internal power switch and one current sink, is designed to provide a robust solution for applications such as automotive infotainment, cluster and centre-stack lighting, industrial LCD displays, portable DVD players, flatbed scanners, and LED lighting.

The A8513 can operate from a single power supply from 4.5 to 40 V to accommodate start/stop, cold-crank and load-dump requirements. The 2 MHz switching frequency of the boost converter allows the device to operate above the AM radio band.

The new device features robust FMEA (failure modes & effects analysis) performance, and constantly monitors the state of the system to determine if any fault conditions occur, with a fault flag pin alerting the controller to possible fault conditions. If required, the fault flag can be used as part of a circuit to drive an external p-type FET to disconnect the input supply from the system in the event of a fault.

Built-in protection is provided against output short-circuit and overvoltage, open or shorted diode, open or shorted LED pin, shorted boost switch or inductor, shorted current-setting resistor, and IC overtemperature. A dual-level cycle-by cycle current limit function provides soft start and protects the internal current switch against high-current overloads.

The A8513 is supplied in both eMSOP-10 and eTSSOP-16 packages. Various oscillator frequencies are available to meet customer requirements.

For a copy of the data sheet, visit