LAB #5

MULTIPLEXORS AND DEMULTIPLEXORS

• Prelab Assignment
  • ...

• Integrated Circuits
  • 74138: 3-to-8 Line Decoders

  • 74139: 2-to-4 Line Decoders

  • 74151: 8-to-1 Data Selector/Multiplexor

  • 74153: Dual 4-Line-To-1-Line Data Selector/Multiplexer

  • 74157: Quadruple 2-Line-To-1-Line Data Selector/Multiplexer

• Laboratory Experiments
  1. Design a circuit to implement the following expression: F(A,B,C) = A'B'C' + A'BC" + A'BC + AB'C.
     1. Using an 8-to-1 Multiplexor (74151).

     2. Using a dual 4-to-1 Multiplexor (74153).

     3. Using a 3-to-8 decoder (74138).

  2. A circuit is needed to display a 4-bit value on the LED's of the logic designer. This value can come from 2 different sources. Design a circuit using four 2-to-1 multiplexors to select which of the two values to display on the LED's. Use an input switch on the logic designer to select the input source. The two values to be displayed should be hardwired to the binary equivalent of 0x5 and 0xA.

  3. Design a circuit that given a 2-bit value will light an LED corresponding to that value. Thus for each of the four possible input values (0 through 3), one of the four LEDS should be lit. Obtain the input value from the two switches on the D/A trainer.