New Industry Products

austriamicrosystems Unveils 16-channel Constant Current LED Drivers with Diagnostic Function

February 22, 2007 by Jeff Shepard

austriamicrosystems introduced the AS1110 16-channel constant current LED driver with advanced error diagnostics for open and shorted LEDs. The AS1110 follows the AS1109 while doubling the output channels. The AS1110 uses the serial data input/output lines for the error information readback so that no additional PCB tracks are needed for LED error diagnostics.

The AS1110 features sixteen regulated ports that provide constant current for driving LEDs within a wide range of forward voltage variations. The AS1110 output ports are guaranteed to endure a maximum voltage of 15V. Through an external resistor the currents can be adjusted from 0.5 to 100mA which gives the utmost flexibility in controlling LED brightness. With an accuracy of ±3% between channels, the AS1110 improves picture quality of LED displays since intensity variations between LEDs and LED modules completely disappear.

The AS1110, as the AS1109, can be used in multiplexed mode, meaning that a single AS1110 can drive up to 64 independent LED nodes. In this multiplexed mode the AS1110 still maintains the full functionality of the error detection. Another highlight of the AS1110 is the built-in LED error detection, which can be invoked during normal operation without switching into a separate detection mode. The AS1110 can detect any open- or short-circuit as well as an over-temperature occurrence. For immediate detection of those errors, a global error flag is available at serial data output, detecting any of those errors quickly and precisely. Furthermore, a detailed error report can be produced with the exact position of the broken LED.

In order to avoid the typical flickering of LED displays during error detection, austriamicrosystems has introduced the Low-Current Diagnostic mode. In this mode, a small test current of only 0.6mA is applied to the display for a very short time. As a result, LED testing is not visible and can therefore be applied during normal operation.

The fast 30MHz serial interface ensures high refreshing rates even for huge LED display modules. With an operating temperature range from -40 to +85°C, the AS1110 is also well-suited for industrial and outdoor applications. The AS1110 is available in a 24-pin SSOP-150 and a small 28-pin QFN (5x5mm) package, allowing a very small pitch between LED pixels which is suitable for indoor LED displays.