LOW POWER LED-BASED MARQUEE SYSTEMS

Abstract

A low power LED based marquee is described. The LEDs are powered by 3.3 VDC.

Description

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows a block diagram of a low power marquee. The diagram highlights the technique of driving marquee LEDs.

FIG. 2 shows schematic of driving a typical single LED.

Claims

1. An LED based message display comprising of a matrix of light emitting diodes organized in multiple rows and columns with switching means to switch power on or off to each row or column, said switching means containing field effect transistors with very low on-state resistance.

2. Message display of claim 1 wherein said switching means comprise of said field effect transistors and current limiting resistors.

3. An LED based message display of claim 1 wherein switching means include a high density field programmable gate array controlled by a microprocessor contained in the switching means.

4. Message display of claim 1 wherein said light emitting diodes have pre-sorted uniform luminous intensity.

5. Message display of claim 1 having means to select variety of international fonts for display.

6. Message display of claim 1 having means to communicate to external devices to receive messages to be displayed.

7. Message display of claim 6 wherein said communication means comprise of means to communicate over Ethernet.

8. Message display of claim 6 wherein said communication means comprise of means to communicate over Devicenet or profibus.

9. Message display of claim 6 having means to select the address of said display within a network of such displays.

10. Message display of claim 6 having means to share messages from said external devices with other message displays on a network.

11. An LED based message display comprising of a matrix of light emitting diodes organized in multiple rows and columns with switching means to switch power on or off to each row or column, said power to be a low voltage regulated power supply.

12. An LED based message display comprising of a matrix of light emitting diodes organized in multiple rows and columns with switching means to switch power on or off to each row or column, said power means and switching means having low power losses to eliminate need for an internal fan to dissipate heat from said power losses.