The A8502 is a multi-output white LED driver for small-size LCD backlighting. It integrates a current-mode boost converter with internal power switch and two current sinks. The boost converter can drive up to 24 LEDs, 12 LEDs per string, at 120 mA. The LED sinks can be paralleled together to achieve even higher LED currents, up to 240 mA. The A8502 can operate with a single power supply, from 5 to 40 V, which allows the part to withstand load dump conditions encountered in automotive systems.
If required, the A8502 can drive an external P-FET to disconnect the input supply from the system in the event of a fault. The A8502 provides protection against output short and overvoltage, open or shorted diode, open or shorted LED pin, shorted boost switch or inductor, shorted FSET or ISET 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 A8502 has a synchronization pin that allows PWM switching frequencies to be synchronized in the range of 580 kHz to 2.3 MHz. The high switching frequency allows the A8502 to operate above the AM radio band.
The A8502 is provided in a 16-pin TSSOP package (suffix LP) with an exposed pad for enhanced thermal dissipation. It is lead (Pb) free, with 100% matte tin lead frame plating.
