# What are the basic gates and universal gates?

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.

Similarly, how many basic gates are there?

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. The following illustration and table show the circuit symbol and logic combinations for an AND gate.

What is basic logic gates?

A logic gate is an elementary building block of a digital circuit. Most logic gates have two inputs and one output. At any given moment, every terminal is in one of the two binary conditions low (0) or high (1), represented by different voltage levels.

Who is the inventor of logic gates?

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. Konrad Zuse designed and built electromechanical logic gates for his computer Z1 (from 1935–38).

## Which gates are universal?

A universal logic gate is a logic gate that can be used to construct all other logic gates. There are many articles about how NAND and NOR are universal gates, but many of these articles omit other gates that are also universal gates.

## Why is NOR gate called a universal gate?

A NOR gate is a logic gate which gives a positive output only when both inputs are negative. Like NAND gates, NOR gates are so-called “universal gates” that can be combined to form any other kind of logic gate.

## How does a NOR gate work?

The NOR gate is a digital logic gate that implements logical NOR – it behaves according to the truth table to the right. A HIGH output (1) results if both the inputs to the gate are LOW (0); if one or both input is HIGH (1), a LOW output (0) results. NOR is the result of the negation of the OR operator.

## What is a XAND?

@Matthew Whited:”XAND would be the same as XNOR not XOR.” This is a false statement. XNOR and XOR are themselves different. Just as NOR is the opposite of OR, XNOR is the opposite of XOR. The ‘N’ in NOR stands for “negative” or “negated”.

## How does the NOT gate work?

In electronics, there’s a logic gate that works in the same, contrary way and it’s called a NOT gate or inverter. Unlike AND and OR gates, it has only one input and one output. The output is exactly the opposite of the input, so if the input is a 0, the output is a 1 and vice versa.

## What is the purpose of a NOT gate?

A NOT gate, often called an inverter, is a nice digital logic gate to start with because it has only a single input with simple behavior. A NOT gate performs logical negation on its input. In other words, if the input is true, then the output will be false.

## What is a buffer gate used for?

A buffer has only a single input and a single output with behavior that is the opposite of an NOT gate. It simply passes its input, unchanged, to its output. In a boolean logic simulator, a buffer is mainly used to increase propagation delay.

## What is a current buffer?

Typically a current buffer amplifier is used to transfer a current from a first circuit, having a low output impedance level, to a second circuit with a high input impedance level.

## What is a buffer in a circuit?

A buffer is a unity-gain amplifier that has an extremely high input resistance and an extremely low output resistance. This means that the buffer can be modelled as a voltage controlled voltage source that has a gain of one. Unity gain buffers are idealized circuit elements.

## What is a gate drive circuit?

A gate driver is a power amplifier that accepts a low-power input from a controller IC and produces a high-current drive input for the gate of a high-power transistor such as an IGBT or power MOSFET. In essence, a gate driver consists of a level shifter in combination with an amplifier.

## What is a buffer in VLSI?

A digital buffer (or a voltage buffer) is an electronic circuit element that is used to isolate the input from the output, providing either no voltage or a voltage that is same as the input voltage. The high input impedance is the reason a voltage buffer is used.

## What is 74ls245?

OCTAL BUS TRANSCEIVER. The SN54/74LS245 is an Octal Bus Transmitter/Receiver designed for 8-line asynchronous 2-way data communication between data buses.

## What is 74ls244?

The 74LS244 is a driver used for address bus.These buffers/line drivers are designed to improve both the performance and PC board density of 3-STATE buffers/ drivers employed as memory-address drivers, clock drivers, and bus-oriented transmitters/receivers.

## What is octal buffer?

The 74AC11244 is an octal buffer or line driver designed specifically to improve both the performance and density of 3-state memory address drivers, clock drivers, and bus-oriented receivers and transmitters. The device can be used as two 4-bit buffers or one 8-bit buffer, with active-low output-enable (OE) inputs.

## What is the use of high input impedance?

A high impedance means that the circuit draws or provides little power on the signal. A low impedance means that the circuit draws or provides more power on the signal. Say the circuit under question (circuit B) is interfaced to circuit A on the input side and circuit C on the output side.

## What is the use of buffer IC?

Fundamentally, a buffer is an amplifier. It takes a small signal (lightly loading the source of the signal) and provides a copy of that signal that can drive a heavy (e.g., capacitive) load. They are used in places where connecting the heavy load directly to the source would adversely affect the signal.

## What is the meaning of high impedance?

In electronics, high impedance means that a point in a circuit (a node) allows a relatively small amount of current through, per unit of applied voltage at that point. High impedance inputs are preferred on measuring instruments such as voltmeters or oscilloscopes.

## What is the use of a buffer in circuits?

A buffer is a unity gain amplifier packaged in an integrated circuit. Its function is to provide sufficient drive capability to pass signals or data bits along to a succeeding stage. Voltage buffers increase available current for low impedance inputs while retaining the voltage level.

Categories FAQ