Allegro tailors LED drivers for small-size LCD backlighting

Allegro MicroSystems Inc. rolled out a pair of multi-output LED drivers for backlighting automotive LED displays.

The A8502 and A8514 integrate a current-mode boost converter with internal power switch and multiple current sinks. The LED sinks can be paralleled together to achieve even higher LED currents. They are capable of operating from a single power supply from 5 V to 40 V, which allows them to withstand load dump conditions in automotive systems.

The A8502 and A8514 LED drivers can optionally drive an external PMOS to disconnect input supply from the system in the event of a fault. The devices, coupled with the external PMOS disconnect switch, provide protection against output short and overvoltage, open or shorted diode, open or shorted VLED pin, and over-temperature.

A dual level cycle-by-cycle current limit function provides soft start and protects the internal current switch against high current overloads. They have a high PWM switching frequency (>2 MHz), which allows them to operate above the AM radio band. They also have a synchronization pin if the user wishes to be synch in the range of 600 kHz to 2.25 MHz.

Pricing: The A8502KLPTR-T is priced at $2.13 and the A8514KLPTR-T is priced at $2.24 - both in quantities of 1,000. 

Availability: The A8502KLPTR-T is offered in the 16-pin SSOP package and the A8514KLPTR-T is offered in the 20-pin SSOP package both with an exposed thermal pad.

Datasheets: A8502 and A8514