Following points summarize ECL advantages over TTL and CMOS: ➨It has fanout of 25 which is better than TTL and less then CMOS. ➨It has average propagation delay time ( 1 to 4 ns ) better compare to both TTL and CMOS. Hence it is known as fastest logic family.

Explanation: ECL is the fastest of all the logic families because of the emitters of many transistors are coupled together which results in the highest transmission rate.

Emitter-coupled-logic (ECL) is a BJT logic family that is generally considered the fastest logic available.

ECL

However, CMOS is slowest among the given logic family because of the high input impedance (i.e., due to SiO2) takes more time for charging and discharging.

There are seven basic logic gates: AND, OR, XOR, NOT, NAND, NOR, and XNOR. The AND gate is so named because, if 0 is called “false” and 1 is called “true,” the gate acts in the same way as the logical “and” operator.

Computers need a way to manipulate those 1s and 0s, so that they can eventually do more complicated operations like calculating the 50th digit of π. Computers use logic gates to transform the 1s and 0s from input wires. A logic gate accepts inputs and then outputs a result based on their state.

Ludwig Wittgenstein introduced a version of the 16-row truth table as proposition 5.101 of Tractatus Logico-Philosophicus (1921). Walther Bothe, inventor of the coincidence circuit, got part of the 1954 Nobel Prize in physics, for the first modern electronic AND gate in 1924.

A universal gate is a gate which can implement any Boolean function without need to use any other gate type. The NAND and NOR gates are universal gates. In practice, this is advantageous since NAND and NOR gates are economical and easier to fabricate and are the basic gates used in all IC digital logic families.

It is a combinational circuit which have many data inputs and single output depending on control or select inputs. Multiplexer can act as universal combinational circuit. All the standard logic gates can be implemented with multiplexers.

∴ NAND and NOR gates are called universal gates because they can be combined to produce any of the other gates like OR, AND, and NOT gates. Hence the correct option is option (B).

De Morgan’s Theorem, T12, is a particularly powerful tool in digital design. The theorem explains that the complement of the product of all the terms is equal to the sum of the complement of each term. Likewise, the complement of the sum of all the terms is equal to the product of the complement of each term.

DeMorgan’s Theorem is mainly used to solve the various Boolean algebra expressions. The Demorgan’s theorem defines the uniformity between the gate with the same inverted input and output. It is used for implementing the basic gate operation likes NAND gate and NOR gate.

In algebra, De Morgan’s First law or First Condition states that the complement of the product of two variables is corresponding to the sum of the complement of each variable. In other words, according to De-Morgan’s first laws or first theorem if ‘A’ and ‘B’ are the two variables or Boolean numbers.

DeMorgan’s Theorem Statement: The complement of the sum of two or more variables is equal to the product of the complements of the variables. If X and Y are the two logical variables, then according to the De Morgan’s Theorem we can write: (X + Y)’ = X’.

DeMorgan’s Laws

1. Combine sets using Boolean logic, using proper notations.
2. Use statements and conditionals to write and interpret expressions.
3. Use a truth table to interpret complex statements or conditionals.
4. Write truth tables given a logical implication, and it’s related statements – converse, inverse, and contrapositive.

SOP is a method of describing a Boolean expression using a set of minterms or product terms. POS is a method of describing a Boolean expression using a set of max terms or sum terms.

The “Don’t care” condition says that we can use the blank cells of a K-map to make a group of the variables. To make a group of cells, we can use the “don’t care” cells as either 0 or 1, and if required, we can also ignore that cell.