Table of Contents
How is an AND gate constructed?
A simple 2-input logic AND gate can be constructed using RTL Resistor-transistor switches connected together as shown below with the inputs connected directly to the transistor bases. Both transistors must be saturated “ON” for an output at Q.
How many transistors does it take to make a AND gate?
A NOT gate is 1 transistor. A NAND gate is 1 transistor per input. A NOR gate is 1 transistor per input. An AND gate is basically a NAND gate + a NOT gate, so it takes 1 transistor more than a NAND gate.
What are the 2 differences between an AND gate and an OR gate?
However, the two are mainly differentiated on the basis of logic operation performed by them. The crucial difference between AND gate and OR gate is that AND gate performs multiplication of the digital inputs. As against the OR logic gate is used to execute the addition of the digital inputs.
How do you make an AND gate from NAND?
AND: You can create an AND gate by using two NAND gates. The first NAND gate does what NAND gates do: returns LOW if both inputs are HIGH and returns HIGH if both inputs are anything else. Then the second NAND gate is configured as a NOT gate to invert the output from the first NAND gate.
What are the three basic gates?
All digital systems can be constructed by only three basic logic gates. These basic gates are called the AND gate, the OR gate, and the NOT gate. Some textbooks also include the NAND gate, the NOR gate and the EOR gate as the members of the family of basic logic gates.
Can AND gate have 3 inputs?
Like the AND gate, the OR function can have any number of individual inputs. However, commercial available OR gates are available in 2, 3, or 4 inputs types. Additional inputs will require gates to be cascaded together for example.
How do you make a transistor NOT gate?
The operation of this circuit is simple. The input is connected through resistor R2 to the transistor’s base. When no voltage is present on the input, the transistor turns off. When the transistor is off, no current flows through the collector-emitter path.
Which logic family is the fastest one?
Emitter-coupled-logic (ECL) is a BJT logic family that is generally considered the fastest logic available. ECL achieves its high-speed operation by employing a relatively small voltage swing and preventing the transistors from entering the saturation region.
Are logic gates made up of transistors?
“A logic gate in a microchip is made up of a specific arrangement of transistors. For modern microchips, the transistors are of the kind called Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET), and the semiconductor used is silicon. “In a logic-gate arrangement, each of the MOSFETs works like a switch.
What is the truth table of NOT gate?
Truth table is a table that gives output for all possible combinations of inputs to a logic circuit. NOT GATE: A logic gate which performs the function of logical operator NOT is called as NOT gate.
What are the seven logic gates?
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.
What are the 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.
How many NAND gates are required to make an AND gate?
If none of the AND gate’s inputs are HIGH, the output is LOW. Using two NAND gates one can make an AND gate.
What does a NOT gate look like?
The standard NOT gate is given a symbol whose shape is of a triangle pointing to the right with a circle at its end. This circle is known as an “inversion bubble” and is used in NOT, NAND and NOR symbols at their output to represent the logical operation of the NOT function.
What is bubbled AND gate?
A bubbled OR gate is the combination of two NOT gates and one OR gate. That is, the output of two NOT gates is made as input of OR gate. This expression represents NAND gate. Hence, a bubbled OR gate is equivalent to a NAND gate.
What does a NOT gate do?
A NOT gate inverts the input – the output is 1 (TRUE) if the input is 0 (FALSE), and the output is 0 (FALSE) if the input is 1 (TRUE).
What does the NOR gate do?
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 fundamental gate?
Logic gates perform basic logical functions and are the fundamental building blocks of digital integrated circuits. Most logic gates take an input of two binary values, and output a single value of a 1 or 0. Some circuits may have only a few logic gates, while others, such as microprocessors, may have millions of them.
Do we need to ground the unused input for AND gate?
To ensure that the gates are not left floating they should be connected either to ground or to the supply rail. Often it will not matter which is used, unless it is an input on a used function when the required input, either high or low would mean connecting it to the supply rail or ground respectively.
Which gate produces 1 when all inputs are high?
In digital electronics, a NAND gate (NOT-AND) is a logic gate which produces an output which is false only if all its inputs are true; thus its output is complement to that of an AND gate. A LOW (0) output results only if all the inputs to the gate are HIGH (1); if any input is LOW (0), a HIGH (1) output results.
