Constant-current driver finds faults in LED panels

Edited by the Electronicstalk editorial team Jan 17, 2008

Silent error detection features full LED panel coverage to detect even dark pixels in real time.

New from Macroblock, the MBI5039 is a constant-current LED driver with silent error detection aimed at LED panel applications.

There are currently two key issues for manufacturers of LED panels: video image quality and real-time error detection over the full LED panel.

Macroblock's new device addresses both these criteria, making it easy to detect dark pixel errors, which is especially useful in commercial LED panels and traffic signs.

The MBI5039 is a 16-channel constant current LED driver with smart error detection functions.

The device supports constant output currents from 3 to 90mA and sustains up to 17V at the output ports.

In addition, the high clock frequency (30MHz) satisfies system requirements for high volume data transmission.

The MBI5039 includes two error detection functions: "in-message error detection" and "silent error detection".

In-message error detection performs the online detection as data-in and error-out sequentially, making it easy to identify open- and short-circuit LEDs and report the exact position of the broken device.

Silent error detection features full LED panel coverage to detect even dark pixels in real time.

It diagnose the LED at low current (0.1mA) within short period (500ns) to avoid flickers or noise on the LED panel, assuring the accuracy of the display information.

In addition to the two featured error detection schemes, thermal detection is also available to protect the system from overtemperature.

The MBI5039 also provides a 64-step programmable current gain for LED brightness and uniformity adjustment.

And for improved display uniformity, the MBI5039 promises output current accuracy within 1.5% variation between channels and within 3% variation between ICs.

The MBI5039 also delivers fast output current response, with a 35ns minimum output pulse, which greatly enhances the grey scale rendering and the visual refresh rate of the LED panel.

The MBI5039 can be used as a drop-in replacement for the company's MBI5025, MBI5026, MBI5027, MBI5028 and MBI5029 devices, offering improved display quality with full LED panel detection and real-time online error reporting to reduce maintenance costs.