Circuits in SSI -- II

Start off by reviewing a two chips you saw in Lab 6.

7404
Hex inverter
7400
Quad 2-input NAND gates

We'll use them in this lab to implement the half adder shown below.

half adder circuit

Task 1

Your lab instructor will get you started by showing you how to make input switches and output LED's. Warning: The LED's you use in this lab are not normal LED's. These LED's have built-in current limiting resisters. If you try this at home, be sure to use resisters.

Task 2

Figure out how to use one 7404 and one 7400 to implement the circuit. Construct a wiring diagram and show it to your lab instructor.

       7404                     7400              
    +---\/---+               +---\/---+      
 1 -|1A   Vcc|- 14        1 -|1A   Vcc|- 14 
 2 -|1/Y   6A|- 13        2 -|1B    4A|- 13 
 3 -|2A   6/Y|- 12        3 -|1/Y   4B|- 12 
 4 -|2/Y   5A|- 11        4 -|2A   4/Y|- 11 
 5 -|3A   5/Y|- 10        5 -|2B    3A|- 10 
 6 -|3/Y   4A|-  9        6 -|2/Y   3B|-  9 
 7 -|gnd  4/Y|-  8        7 -|gnd  3/Y|-  8 
    +--------+               +--------+     

Task 3

Following the guidence of your instructor build the halfadder with the 7404 and 7400. Before you power-on your circuit, have it checked by one of your labmates.


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