2/26/2003 - Enhancing portable color displays and providing up to 85 percent power conversion efficiency to extend battery life and system run-times, Texas Instruments Incorporated (TI) (NYSE: TXN) announced a new 28V white light-emitting diode (LED) driver and a liquid crystal display (LCD) boost converter that significantly helps control brightness and improve quality of LEDs and LCDs in portable applications.
In addition to the new white LED driver, TI's TPS61045 adjustable LCD bias boost converter features a digitally programmable output of up to 28V, which allows for precise contrast control of small- to medium-sized LCD displays without the need for any external components. In addition, the TPS61045 provides a true shutdown feature that disconnects the load from the input and provides controlled power up/down sequencing of the display.
Both converters feature a high switching frequency of 1 MHz, which significantly reduces a portable designer's reliance on external components. Each device is packaged in a tiny 3x3 mm2 QFN package made possible through TI's advanced processing manufacturing capabilities. This allows designers who use TPS61042 and TPS61045 to reduce board space and system cost.
TI's TPS61042 high frequency white LED driver has a 1.8V to 6V input range and supplies output voltages up to 28V, and can drive up to eight white LEDs with a constant current. The driver allows the LED current to be set with an external sense resistor. To control LED brightness, the LED current can be pulsed by applying a pulse width modulated (PWM) signal with a frequency range of 100 Hz to 50 kHz to a control pin. The control input in the TPS61042 also allows disabling the part and disconnects the LEDs in order to avoid current leakage during shutdown. The device also can be configured so that brightness levels can be controlled by an analog signal.
Pricing and Availability
The TPS61042 and TPS61045 devices are available today in volume from TI and its authorized distributors. The devices come in an eight-pin QFN package. Suggested resale pricing in quantities of 1,000 is $1.10 for the TPS61042 and $1.25 for the TPS61045. Evaluation modules are currently available through power.ti.com.
Previous Page | News by Category | News Search
If you found this page useful, bookmark and share it on: