Instructables
Picture of Date of Birth Project
The Date of Birth Project is a breadboard circuit that displays a person's day of birth (in this case 07/21/1996).                                          Design Specifications:  1.) must be common cathode 2.) 150 ohms-270 ohms 3.) K-mapping 4.) 2 chips must be NAND 5.) 2 chips must be NOR
 
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Step 1: Starting the Project

Picture of Starting the Project
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To begin this project you need to understand exactly what you are getting yourself into: A seven segment display is similar to a scoreboard you find at a basketball game. Each segment acts on its own depending on the word. So, this project has three switches so each switch can go off or on. Where a switch is off or on changes the number on the seven segment display. This is a quick foreshadowing of all the steps that will be forthcoming. First, you create a chart that will show a number on each line of your truth table (truth table is shown in the picture). Also, I've included all the supplies needed for this epic adventure.

Step 2: K-Mapping

Picture of K-Mapping
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After you finish your truth table, you are now ready to develop a word for each segment. To find your word, you use a method called K-mapping; K-mapping is a quick and easy process to find groups when the switch is on (creating a word). The picture has a couple examples of when a segment is on, the group is created, and the what word is implemented.

Step 3: Developing the Circuits

Picture of Developing the Circuits
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After you have all your words for each segment, you are ready to develop the circuits. Picking the type of circuit is simple, draw a circuit for AOI, NAND, and NOR then choose the circuit that has the least amount of chips (less chips= more space on breadboard). Repeat this step for all segments. For this birthday there are 12 chips including R-Pack, 1 inverter, 2 AND, 2 OR, 2 NAND, and 4 NOR.
zombiemom4210 months ago
I did ths project in class too