Tag Archives: matrix


Design considerations for a wireless LED sign

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This application note from Texas Instruments describes the hardware design considerations for making a multi-sport scoreboard that is cost efficient, portable, easy to use, and support wireless transmission of display data.

Designing an LED scoreboard

Designing an LED scoreboard

This application report describes the selection of the following: an appropriate LED display, a controller system, a communication system, and software for building the wireless LED-based scoreboard. Different techniques are included to drive the LED display from a microcontroller as well as some test results. This application report is only for displaying numerals on the scoreboard but the same concept can be applied to display alphabets. A similar concept can be extended to large LED-display modules with multiple 16 × 16 or 24 × 24 matrices.

Theory of Matrix Keypad

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Tact switches are widely used as digital input devices. Normally one tact switch requires one digital I/P pin of a microcontroller but if you want to interface a matrix of such switches (say a 16 digit keypad), assigning a digital I/O pin for each key won’t be a good idea. You need to think about the way to minimize the required number of digital I/O pins of microcontroller. A very popular method is a keypad matrix where the keys are arranged into rows and columns so that a 4×4 (16) tact switches can be interfaced to a microcontroller using only 4+4 = 8 I/O pins. Read more