Texas Instruments Drives 60 White LEDs with TPS61181 LED Driver

Helping display manufacturers meet demands for more efficient power technologies in displays, Texas Instruments Incorporated (TI) (NYSE: TXN) 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.

Texas Instruments (TI) TPS61181 White LED DriverNotebook and other LCD displays 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. 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

Pricing and availability
The TPS61181 is available today in volume from TI and its authorized distributors. The suggested resale price is $1.75 in 1,000-unit quantities. Application notes and related LED products for notebook displays are available for download. A TPS61181EVM-259 evaluation module is also available and suggested resale price is $49.

LED driver and display solutions
TI provides the broadest portfolio of high-performance products for today’s LED design requirements, including power management, such as AC/DC, power factor correction, DC/DC and linear power conversion; RF transceivers; digital signal processors (DSPs); and ultra-low-power microcontrollers. TI’s products support applications ranging from ultra-small portable displays to the largest lighting and display panels in the industry. Additionally, TI’s local support and applications expertise help designers get to market faster. See: www.ti.com/led.