Raleigh, NC—Bringing new functionality to traditional LED driver chips, austriamicrosystems' AS1109 integrates LED error-diagnostic readback circuitry for detecting open and shorted LEDs and thermal anomalies for a variety of large fixed, slow-rolling and bar-graph displays, industrial controller displays, and traffic signs.
"As the resolution of LED displays increases, the market demands more accurate LED drivers in smaller packages," said Walter Moshammer, director of marketing for Standard Linear devices. "Additionally, LED error detection is becoming a very important factor, not only for security related applications like traffic signs, but also for more commercial applications like information displays or video walls in order to optimize maintenance cost."
The AS1109 features eight regulated current ports that provide a constant-current output for driving LEDs within a wide range of forward voltage variations. The chip touts best-in-class accuracy: ±2 percent between channels and ICs. Users can adjust output current from 0.5 to 100 mA per channel with an external resistor. The chip's 30 MHz serial interface ensures high refreshing rates even for large LED display modules.
The built-in LED error detection function for detecting LED faults and over-temperature conditions, coordinated via the serial interface for readback of error information, is intuitive and thus easy to use. It can be invoked during normal operation without switching into a separate detection mode. A global error flag signals a fault, and users can single out the specific damaged LED. A Low-Current Diagnostic mode minimizes flickering of the LED display during error detection. In this mode, a test current of just 0.6 mA is momentarily applied to the display. Thus LED testing is visibly transparent.
The chip is rated for operation over -40 to +125°C, and so the AS1109 is well suited to industrial and outdoor applications. Click here to access the device datasheet. The AS1109, available in a 16-pin SOIC-150, 16-pin SSOP-150, and a 4-by-4 mm 16-pin QFN package, is priced at $1.01 each in 1,000-unit quantities.
austriamicrosystems, 1-919-676-5292, www.austriamicrosystems.com