Universal gates-NOR Gate

Universal gates-NOR Gate
Universal gates-NOR Gate

Universal gates should be discussed before NOR gate with SR flip-flop, SR latch, RS latch, or memory device construction. NAND and NOR gates are universal because they can generate any fundamental gate. These two gates are ubiquitous since they can be used for anything. An inverter made from NAND gates can be used to make a NOR gate. We should learn how to acquire the following results because they always occur between exercise questions. Learn how to connect NOT and NAND gates first.

Universal gate digital electronics can generate all basic digital logic gates in one circuit. It can emulate AND, OR, NOT, NOR, NAND, and X-OR gates. If any gate is missing, it’s not Universal. Universal gate implementations are simpler and more efficient than complex circuits. The most frequent universal gates are NAND and NOR.

Hi there! NOR gates appear frequently in logic gates and digital electronics. comprehending the NOR gate is essential to comprehending more complicated logic devices. Let’s simplify in 100 words or less. We’ll define NOR gates, their symbols, and how they differ from OR gates. We’ll cover truth tables and basic applications. NOR gates will make sense at the end, and you’ll be ready for adders and flip flops. Sound good? Let’s begin!

What Is a NAND Gate?

Electronic circuits employ universal logic gates like NOR gates. Its output is the opposite of the OR gate, hence “NOT OR.”. Only when all inputs are LOW (0) does the NOR gate output HIGH (1). LOW (0) outputs if any inputs are HIGH.Because they’re “functionally complete” NOR gates can be used to build any logic circuit. They are vital to computer architecture and integrated circuit design due to this feature.

How NOR Gates Work

A simple NOR gate contains two or more inputs and one output. How it works:

  • All inputs LOW (0) produce HIGH (1) output.

If any inputs are HIGH (1), output is LOW (0).
As an example:

  • Inputs A and B are LOW (0, 0) : Output = HIGH (1)
  • A input is LOW (0) and B input is HIGH (1). Zero output.
  • A and B inputs are HIGH (1, 1), resulting in LOW (0) output.
  • NOR gates are opposite OR gates. OR gates output HIGH if any input is HIGH, but NOR gates only output HIGH if all inputs are LOW.

Uses of NOR gates

Combinational logic circuits: NOR gates can output dependent on input combinations. Example: AND gate construction.
Flip-flops and latches: SRAMs use NOR gates.
NOR gates encode and decode multiple inputs into one output or many outputs from one input.
Clock signals can be generated by wiring NOR gates into oscillating loops.
Although simple, NOR gates are crucial to all digital logic circuits and computer designs. Knowing how NOR gates function is essential for mastering advanced electronics.

How Do NOR Gates Work?

Digital circuits use universal logic gates like NOR gates. It’s a NOT gate followed by an OR gate, therefore “NOT OR”. A NOR gate outputs HIGH (1) only when both inputs are LOW (0). One or both HIGH inputs produce LOW output.

NOR gates have several uses. These gates can be joined to construct any fundamental logic gate. Complex digital circuits and microprocessors need several NOR gates.

Let’s look at a simple NOR gate with two inputs (A and B) and one output (Q) to learn how it works. This truth table shows how inputs affect output:

A B A Q 0 0 1 0 1 0 1 0

Q is HIGH (1) when A and B are LOW (0). In other cases, if A or B are HIGH (1), Q is LOW (0).

The NOR gate is an OR gate followed by a NOT gate, hence its name. The OR gate outputs 1 if any input is 1. If any inputs are 1, the NOT gate inverts the output, therefore the final output is 0. Only when all inputs are 0, does the NOR gate output 1.

A simple two-input NOR gate works like that. Combining NOR gates lets you build more complicated logic circuits for valuable functions. NOR gates are crucial to many digital systems and applications.

Truth Table and NOR Gate Symbols

The global NOR gate can implement any Boolean function alone or in combinations. See how the NOR gate works by breaking it down.

A NOR gate has two or more inputs and one output. The output signal is the OR gate’s inverse. The output is “high” or 1 only when all inputs are “low” or 0. If any inputs are high, output drops.

NOR gates look like OR gates with circles on their outputs, called inverters. Inverters indicate inverted output. Symbol for two-input NOR gate:

Truth tables display output for all input combinations. Truth table for two-input NOR gate:

1 Input 2 Output 0 0 1 0 1 0 1 0 0 1 1 0

If either input is high (1), the output is low (0). Output is high (1) only when both inputs are low (0).

Any Boolean function can be constructed using only NOR gates, making it universal. Combining NOR gates creates AND, OR, NOT, NAND, XOR, and XNOR gates. In integrated circuits, NOR gates implement complicated digital logic functions.

Learning NOR gate logic symbols, inputs and outputs, and truth tables can help you build more complicated digital logic circuits. Have more questions? Let me know!

Real-World NOR Gate Applications

NOR gates are useful in electronics and computers. Here are some major NOR gate uses:

Memory Storage

Data is stored in SRAM and ROM chips using NOR gates. They are useful for memory storage since they can stay in one condition forever. NOR gates were employed to make key system software ROM chips in older systems.

Functions of logic

Any logical function can be implemented with NOR gates. You may make AND, OR, NAND, XOR, and XNOR logic circuits by connecting several NOR gates. Circuit designers build complicated logic systems and circuits using NOR gates.


A clock oscillator can be made from NOR gates. An odd number of NOR gates in a loop creates a simple ring oscillator. Microcontrollers and other digital logic devices use this oscillator to produce a clock signal from an unstable condition. Gate number and propagation delay determine oscillator frequency.

Decoders use NOR gates to turn binary data into useable form. NOR decoders activate one of two output lines based on a binary input code, where n is the number of inputs. This helps select one output from numerous using a binary address.

Latch and flip-flops, essential memory elements in sequential logic and digital circuits, are often made with NOR gates. Multiple NOR gates can be used to make flip-flops and SR latches.

NOR gates are essential to digital electronics and computers. Their simple logic function and steady-state stability make them essential for memory, logic circuits, timing devices, and more. Many digital systems we utilize daily use NOR gates, which are typically overlooked.


For beginners, the simple but versatile NOR gates is explained. A simple inverted OR gate, the NOR underpins current computing logic. Use your new NOR understanding to experiment. Build simple logic circuits with NOR chips or get schematics for gadgets you may make. When you know the basics, the possibilities are unlimited. NOR gates may help you create the next revolutionary technology! Remember, the active electronics community can help with any issues.

Be the first to comment

Leave a Reply

Your email address will not be published.