LED Drivers Suit Backlighting Applications

Jul 19, 2006 12:00 PM

Three white LED drivers from ON Semiconductor are designed to drive high-brightness LEDs in backlighting applications. With up to 90% efficiency and a 0.6-mm package profile, the devices help designers meet stringent power and board-space budgets. Both inductive and charge-pump topologies are available.

The NCP5010 supplies up to 22 V to power a series of two to five white LEDs for LCD backlighting applications. Delivering up to 84% efficiency and 1 μA shutdown current, the NCP5010 operates on input voltages from 2.7 V to 5.5 V.

It features true cut-off, short-circuit and overvoltage protection, and offers under voltage lockout. The 1 MHz frequency of the device’s integral pulse-width modulation (PWM) boost converter and the integration of a Schottky rectifier enables board designs to be optimized for small inductors and capacitors.

The NCP5604A and NCP5604B drive either 3 LEDs or 4 LEDs, respectively at up to 25 mA of current per LED. Current matching tolerances of 0.5% ensure uniform LED brightness.

Delivering up to 90% efficiency and less than 1 μA quiescent current, these devices operate on input voltages from 2.7 V to 5.5 V and feature unique short-circuit and overvoltage protection. Both the NCP5604A and NCP5604B are offered in a QFN package (WQFN) that requires only 0.8 mm of profile room.

The NCP5010 is offered in an 8-pin, 1.7 mm x 1.7 mm x 0.6 mm flip-chip package. It is priced at $0.67 per unit; the NCP5604A is offered in a WQFN-16 package and priced at $0.69 per unit; the NCP5604B is offered in a WQFN-16 package and priced at $0.66 per unit, all prices for 3000-unit quantities.