Digital-electronics 简明教程
Implementation of NOT Gate from NOR Gate
非门是一种基本逻辑门，它给出的输出是其输入的补码。或非门是一种通用逻辑门，可用来实现任何其他类型的逻辑门。一个或非门基本上是一个或门后跟一个非门。
A NOT Gate is a basic logic gate that gives an output which is complement of its input. A NOR gate is a universal logic gate that can be used to implement any other type of logic gate. A NOR gate is basically an OR gate followed by a NOT gate.
阅读本教程了解如何使用或非门实现非门。让我们从非门和或非门的简要概述开始讨论。
Read this tutorial to find out how you can implement a NOT gate using NOR gate. Let’s start the discussion with a brief overview of NOT and NOR gates.
What is a NOT Gate?
在数字电子学中， NOT gate 是一种基本逻辑门，它只有一个输入和一个输出。它是一种无论其输入如何，其输出总是为其输入的补码的逻辑门类型。因此，非门也被称为 inverter. 。
In digital electronics, a NOT gate is a basic logic gate that has only one input and one output. It is type of logic gate whose output is always the complement of its input. Therefore, the NOT gate is also known as an inverter.
如果非门的输入为低电平（逻辑 0），则其输出为高电平（逻辑 1）。如果输入为高电平（逻辑 1），则非门输出低电平（逻辑 0）。非门的逻辑符号如图 1 所示。
If the input of the NOT gate is LOW (Logic 0), then it gives an output that is HIGH (Logic 1). If the input is HIGH (Logic 1), then the NOT gate gives the LOW (logic 0) output. The logic symbol of the NOT gate is shown in Figure-1.
非操作用“—”（条形）符号表示。因此，如果非门的输入变量为 A，则其输出 Y 由下式给出：
The NOT operation is represented by the '-' (bar) symbol. Therefore, if the input variable of the NOT gate is A, then its output Y is given by,
\mathrm{Y \: = \: \bar{A} \: = \: A' }
What is a NOR Gate?
NOR 门是一种通用门，因此，它可用于实现任何其他类型的逻辑门。NOR 门本质上是非门和或门的组合，即或门后跟随一个非门即为 NOR 门。因此，
NOR gate is a type of universal gate, therefore, it can be used to implement any other type of logic gate. NOR gate is basically a combination of NOT gate and OR gate, i.e. OR gate followed by a NOT gate is a NOR gate. Thus,
\mathrm{NOR \: Gate \: = \: OR \: Gate \: = \: NOT \: Gate}
NOR 门可以接受任意数量的输入并给出单个输出。仅当所有输入都为低或逻辑 0 时，NOR 门的输出才假定为高或逻辑 1。对于任何其他输入组合，NOR 门的输出都假定为低或逻辑 0。两输入 NOR 门的逻辑符号如图 2 所示。
A NOR gate can accept any number of inputs and gives a single output. The output of the NOR gate is assumed HIGH or Logic 1, only when all of its inputs are LOW or Logic 0. For any other combination of inputs, the output of the NOR gate is assumed LOW or Logic 0. The logic symbol of a two input NOR gate is shown in Figure-2.
NOR 门的操作表示为，
The operation of the NOR Gate is expressed by,
\mathrm{Y \: = \: \overline{A \: + \: B} \: = \: (A \: + \: B)'}
其中，A 和 B 是输入变量，Y 是 NOR 门的输出变量。NOR 门的输出表达式读作“Y 等于 A 加 B 横线”。
Where, A and B are the input variables and Y is the output variable of the NOR gate. The output expression of the NOR gate is read as "Y is equal to A plus B whole bar".
Truth Table of NOR Gate
对于不同的输入组合，我们可以使用真值表分析 NOR 门的操作，真值表如下。
For different combinations of inputs, we can analyze the operation of the NOR gate using its truth table, which is given below.
Input |
Output |
A |
B |
Y = (A + B)' |
0 |
0 |
1 |
0 |
1 |
0 |
1 |
0 |
0 |
1 |
1 |
现在，让我们讨论使用 NOR 门实现非门。
Now, let us discuss the implementation of NOT Gate using NOR Gate.
Implementation of NOT Gate from NOR Gate
如上所述，NOR 门是一种通用门，因此，我们可以使用它来实现任何其他类型的逻辑门。由 NOR 门实现非门如图 3 所示。
As discussed above, a NOR gate is a universal gate, therefore, we can use it to realize any other type of logic gate. The implementation of NOT gate from NOR gate is shown in Figure-3.
因此，要使用 NOR 门实现非门，我们只需将所有输入端子连接在一起，并将要非或逆转的信号应用于此公共输入端子。
Hence, to realize the NOT gate using NOR gate, we simply join all its inputs terminals together and apply the signal to be NOTed or inverted to this common input terminal.
此外，我们可以通过将除一个以外的所有输入端子连接到逻辑 0，并将要逆转的信号应用到剩余端子来使用 NOR 门作为非门。NOR 门作为非门的这种配置称为 controlled inverter.
Also, we can use the NOR gate as a NOT gate by connecting all its input terminals except one to Logic 0, and applying the signal to be inverted to the remaining terminal. This configuration of NOR Gate as NOT Gate is referred to as a controlled inverter.
因此，通过这种方式，可以使用 NOR 门实现非门。
Hence, in this way, the NOT gate can be implemented using a NOR gate only.