Question

Implement a four-input voting device using a single 74151 multiplexer. The voting device has four inputs, a, b, c, and d. When two or more inputs are one, the output is one, f(a,b,c,d)=1. Otherwise, the output is zero. Draw a schematic diagram as a schematic entry (.bdf file) in Quartus.

Quartus has a 74151 device available in the library. Click the "Symbol" icon, follow libraries->others--> maxplus2 to find 74151 in the list. The "Symbol" icon can be found at the top toolbox when you have a .bdf file open.

You can use GND and VCC to set inputs as "0" or "1", if necessary. You can use gates (AND, OR, NOT, NAND, NOR) too. In Quartus, you can find them by clicking the "Symbol" icon, and following libraries --> primitives --> other: gnd and vcc. Or after opening the "Symbol" dialogue window, you can search in the Name box for all of three components.

Answer 1

The student's question pertains to the creation of a schematic diagram for a four-input voting device using a 74151 multiplexer in Quartus II software. They need to design a combinational logic circuit that outputs a high signal when at least two of the inputs are high.

Step-by-step explanation:

The student is asking how to implement a four-input voting device using a single 74151 multiplexer. In this scenario, the multiplexer is used to determine when at least two of the four input signals (a, b, c, d) are at a logic high state (1). The desired function, f(a,b,c,d)=1 when two or more inputs are one, can be achieved by connecting the multiplexer inputs to the four signals and possibly utilizing additional gates to generate the correct select signals and output.

To produce a schematic diagram in Quartus II, you would open a .bdf file, find the 74151 multiplexer in the MAX+PLUS II library, and then arrange the device with any necessary logic gates and connect GND or VCC to the select inputs to delineate the required logic for the voting functionality. You would then connect the circuit according to the logical function that defines the voting condition.

Given the logic function and the constraints of a 74151 multiplexer, the student would be creating a form of simple digital logic circuit within an electronic design software like Quartus II. However, this task also requires knowledge of combinational logic design and the specific features of the 74151 device to complete successfully.