Dot matrix Display System:
Dot matrix Display has a superior font and is useful for alphanumeric displays. In dot matrix displays, the LEDs are organized in rows and columns. To minimize the hardware requirement of the dot matrix display system, a dynamic or stored display is used. This can be done in two ways:
- Horizontal Strobing
- Vertical Strobing
Working Principle of Dot matrix Display:
The block diagram of a 2-digit 5×7 dot matrix display system using horizontal strobing is shown below figure:
Here, the two-digit alphabets or numerals to be displayed in the dot matrix display are given at the inputs of IC 74157 which is actually a quad 2 to 1 multiplexer arranged as a 4-bit or nibble multiplexer. It is based on the select signal obtained from the output of a JK flip-flop, either 4-bits 1A 2A 3A or 1B 2B 3B 4B will be available at the outputs of the multiplexer and act to each digit, to be displayed must be converted into the dot selection code to actiuvate LED dots, one column at a time in five steps for horizontal strobing.