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A combinational logic circuit for traffic control is designed. ___________ GATE can only be used to implement the designed control circuit without any additional GATES.
The logic gate for traffic control is:
For red light
Output X = NOT (J)
For yellow light
Output Y = K
For green light:
Output Z = J AND (NOT K)
Combined Circuit is given as,
Now, all the gates can be formed from NAND gate, as it is a universal gate.
NAND gate will be the correct answer.
In the figure shown, D0 and D1 are digital inputs, S is a control input and Y is the output. When S = 0, then Y = D0. When S = 1, then Y = D1. The given combinational circuit is
A 2-input multiplexer is as shown below.
Output, Y = D0S̅ + D1S
_______ are an example of a combinational circuit.
Combinational Logic circuits:
Combinational Logic circuits are circuits for which the present output depends only on the present input, i.e. there is no memory element to store the past output.
A combinational circuit can have ‘n’ number of inputs and ‘m’ number of outputs as shown:
Combinational circuits are:
Any combinational circuit can be designed using only
A universal gate is the one with which any other Boolean function can be implemented without the need of other gates.
Two universal gates are NAND and NOR.
In this gate, output of logic gate is false only when both the inputs are true. It is the complement of AND gate.
NOR gate: Output of this logic gate is true when both inputs are false.
Half adder is also known as
Sum (S) = A⊕B, Carry = A.B
Number of 2 × 1 Multiplexers are required to implement 64 × 1 Multiplexers
A 64 × 1 multiplexer has 64 inputs so if we use 2 × 1 multiplexers 32 are needed in the first stage for 64 inputs, the output of these 32 multiplexers are connected to inputs of 16 multiplexers in the second stage.
Similarly, in third stage, 8 (2 × 1) multiplexers are used, in fourth stage 4 are used and finally 2 (2 × 1) multiplexers in the fifth stage, 1 in the sixth stage.
Total 2 × 1 multiplexers needed are 32 + 16 + 8 + 4 + 2 + 1 = 63.
The biggest advantage of ECL is:
ECL (Emitter Coupled Logic):
In a 1 to 4 De-multiplexer, how many select input lines are required?
A demultiplexer (or demux) is a device that takes a single input line and routes it to one of several digital output lines.
It consists of 2n outputs and has n selection lines, which are used to select which output line to send the input. It is also called as a data distributor.
Identify the gate from the truth table
1) If B is always Low, the output is the inverted value of the other input A, i.e. A̅.
2) The output is low when both the inputs are different.
3) The output is high when both the inputs are the same.
4) XNOR gate produces an output only when the two inputs are the same.
What determines the output from the combinational logic circuit in Digital Electronics?
The output in a combinational circuit depends on the mixture of input signals present at that moment. It is not determined by the past conditions. The output in a synchronous circuit depends on the mixture of input signals present at that moment and also the past conditions.