USA: Helping display manufacturers meet demands for more efficient power technologies in displays, Texas Instruments (TI) has introduced an innovative, six-channel, 40-V white light emitting diode (LED) driver with a built-in, high-efficiency boost regulator and 1.5-A FET.

The smallest LED driver to manage up to 60 white LEDs at once, the TPS61181 provides high power efficiency and accurate current regulation for medium-sized displays used in notebooks, portable GPS, industrial and medical applications.

Notebook and other LCDs have traditionally relied on CCFL (cold cathode fluorescent lamps) technology to backlight the display. Many portable electronics makers have switched from CCFL to white LEDs for backlighting, allowing for greater power savings and thinner panels. This conversion has already taken place in most smaller LCD applications, such as mobile phones and portable media players (PMPs).

The TPS61181 gives engineers designing medium-sized portable applications an easy path to LED design. The integrated device, which comes in a tiny 0.8 mm x 3 mm x 3 mm QFN package, provides several protection features, including a driver for an external FET to disconnect the battery from the white LEDs during shutdown and over-current conditions.

Enhanced dimming control provides designers a range of brightness
The TPS61181 offers enhanced pulse-width modulation (PWM) brightness dimming control for a 100:1 brightness range. Featuring two patented technologies, the device is designed to minimize any potential audible noise or output AC ripple across a wide dimming duty cycle and frequency range.

Key features of the TPS61181

* 5-V to 24-V input voltage
* 1-MHz switching frequency (a TPS61182 version provides 1.3 MHz)
* Boost output auto-adaptive to white LED voltages
* Six-current sink of 25 mA
* Less than 2.5 percent current matching and three percent accuracy
* Over-voltage protection
* White LED open/short protection
* Input and output isolation during short-circuit and shutdown conditions.

The TPS61181 is now available in volume from TI and its authorized distributors. A TPS61181EVM-259 evaluation module is also available.