Table of Contents
- 1 Why are NAND and NOR gates mostly preferred in logic circuit designing?
- 2 Why would a designer want to form an AND gate from two NAND gates?
- 3 Why NAND NAND realization is preferred over and/or realization?
- 4 What characteristics do the NAND and NOR gates have that make them distinct from the other gates for them to be named as universal gates?
- 5 Why NAND gate is faster than NOR gate?
- 6 Why are NAND and NOR gates known as universal gates?
- 7 Why do we replace the and gate with NAND?
Why are NAND and NOR gates mostly preferred in logic circuit designing?
In general, cells are designed to have similar drive strength of pull up and pull down structures to have comparable rise and fall time. NAND gate has better ratio of output high drive and output low drive as compared to NOR gate. Hence NAND gate is preferred over NOR.
Why do we use NAND gate?
The NAND gate is significant because any boolean function can be implemented by using a combination of NAND gates. This property is called functional completeness. NAND gates with two or more inputs are available as integrated circuits in transistor-transistor logic, CMOS, and other logic families.
Why would a designer want to form an AND gate from two NAND gates?
Because the two inputs of the NAND gate are tied together, only two input combinations are possible: both HIGH or both LOW. If both inputs are LOW, the NAND gate will output HIGH. Thus, the circuit behaves exactly as a NOT gate would. AND: You can create an AND gate by using two NAND gates.
Why NAND gate is more preferred than NOR gate for implementing combinational circuits show with circuit diagram?
NAND has lesser delay than Nor due to the NAND PMOS (size 2 and in parallel) when compared to NOR PMOS (size 4 in series). According to my understanding delay would be the same.
Why NAND NAND realization is preferred over and/or realization?
Explain why NAND-NAND realization is preferred over AND-OR realization? NAND-NAND realization needs only one type of gate(NAND), that minimizes IC package counter. 18. NAND gate is called universal gate because any digital system can be implemented with the NAND gate.
Why do we use NAND and NOR?
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.
What characteristics do the NAND and NOR gates have that make them distinct from the other gates for them to be named as universal gates?
The NAND & NOR gates are called universal gates because they perform all the logical operations of basis gates like AND, OR, NOT.
What is the difference between NAND and NOR gate?
A NAND gate is equivalent to an inverted-input OR gate. An AND gate is equivalent to an inverted-input NOR gate. A NOR gate is equivalent to an inverted-input AND gate. An OR gate is equivalent to an inverted-input NAND gate.
Why NAND gate is faster than NOR gate?
Here’s a DTL gate – it’s a NAND gate. Making a NOR gate needs more transistors and costs more. TTL is pretty much the same as DTL, only it uses transistor emitters instead of diodes on the input. NAND is simpler and takes less parts than NOR, and is faster because of NOR’s additional propagation delay.
Which logic function can be implemented using NAND gates?
Any logic function can be implemented using NAND gates. To achieve this, first the logic function has to be written in Sum of Product (SOP) form. Once logic function is converted to SOP, then is very easy to implement using NAND gate.
Why are NAND and NOR gates known as universal gates?
Why are NAND and NOR gates known as universal gates? NAND and NOR logic gates are known as universal gates because they can implement any boolean logic without needing any other gate. They can be used to design any logic gate too. Moreover, they are widely used in ICs because they are easier and economical to fabricate.
What are the advantages of using only NOR gates for logic?
This means that you can create any logical Boolean expression using only NOR gates or only NAND gates. In practice, this is advantageous since NOR and NAND gates are economical and easier to fabricate than other logic gates. So much so that an AND gate is typically implemented as a NAND gate followed by an inverter (not the other way around)!
Why do we replace the and gate with NAND?
In addition to using 4 + 2 = 6 transistors, this means the AND gate (and an OR gate) consists of two stages of delay. Thus, if we can replace our ANDs with NANDs (and our ORs with NORs), our circuit will function faster.