# What are the basic concepts of digital circuits

### What is meant by digital circuits?

I. Definition and characteristics of analog and digital circuits:

Analog circuits (electronic circuits)

Analog signals

Electronic circuits that process analog signals. The word “analog” refers mainly to the proportional reproduction of voltage (or current) to a real signal.

The main features are:

1, the function of the value of an infinite number;

2, when the image information and sound information changes, the signal waveform also changes, that is, the analog signal to be disseminated in the information contained in the waveform (the pattern of change of the information is directly reflected in the analog signal amplitude, frequency, and phase of the change).

3. Primary analog circuits mainly address two major aspects: 1 amplification, 2 signal source.

4. Analog signals have continuity.

Digital circuits (circuits that perform arithmetic and logical operations)

Digital signals

Circuits that perform arithmetic and logical operations on digital quantities using digital signals are called digital circuits, or digital systems. It is also known as a digital logic circuit because of its logical operations and logical processing functions.

The main features are:

1, at the same time with arithmetic and logical operations

Digital circuits are based on the mathematical basis of the binary logic algebra, using binary digital signals, both arithmetic and logical operations can be easily carried out (with, or, not, judgment, comparison, processing, etc.), and is therefore extremely suitable for arithmetic, comparisons, storage, transmission, control, decision-making and other applications.

2, the realization of a simple, reliable system

Binary as the basis for digital logic circuits, reliability is strong. Small fluctuations in the supply voltage has no effect on it, the temperature and process deviations on the reliability of its work has a much smaller impact than analog circuits.

3, high integration, easy to realize the function

High integration, small size, low power consumption is one of the outstanding advantages of digital circuits. Circuit design, repair, maintenance, flexible and convenient, with the rapid development of integrated circuit technology, digital logic circuits are increasingly integrated, integrated circuit block function with the small-scale integrated circuits (SSI), medium-scale integrated circuits (MSI), large-scale integrated circuits (LSI), very large-scale integrated circuits (VLSI) development from component level, device level, component level, board level up to the system level. to the system level. The design of the circuit is composed of only a number of standard integrated circuit block unit connection and become. For non-standard special circuits, programmable logic array circuits can also be used to realize arbitrary logic functions through programming.

Two, the difference between analog and digital circuits

Analog circuits are circuits that process analog signals; digital circuits are circuits that process digital signals.

The analog signal is a function of time, a continuously varying quantity, and the digital signal is a discrete quantity. Because all electronic systems are to specific electronic devices, electronic circuits as a carrier, in a signal processing, signal acquisition, signal recovery are analog signals, only the middle part of the signal processing is digital processing. Specifically, analog circuits mainly deal with analog signals, do not change with time, time domain and value domain are continuous signals, such as voice signals. Digital signals, on the contrary, are changing, and the processing of digital signals includes the sampling of signals, the quantization of signals, and the encoding of signals.

To give a simple example: to come from afar a small to large sound, with amplitude modulation, analog signal transmission (accordingly, should be used in analog circuits), then the amplitude of the signal in the process of transmission will be more and more large, because it is in the amplitude characteristics of the electrical signal to simulate the sound of the strength of the characteristics.

But if you use digital signal transmission, you have to use a kind of code, each level of sound size corresponds to a kind of code, in the sound input, every time you take a sample, the corresponding code will be transmitted out. No matter how many levels the sound is divided into, no matter how high the sampling frequency is, for the original sound, there is still a loss in this way. However, this loss can be compensated by increasing the sampling frequency, which is theoretically greater than twice the frequency of the original signal.

Digital circuits are standardized in terms of levels; analog circuits are not.

Three, the link between analog and digital circuits

The simulation circuit is to supply power to the digital circuit while completing the implementation of the actuator.

In analog and digital circuits, the signals are expressed in different ways. Operations that can be performed on analog signals, such as amplification, filtering, limiting, etc., can be performed on digital signals. In fact, all digital circuits are fundamentally analog circuits, and their basic electrical principles, are the same as those of analog circuits. A complementary metal-oxide semiconductor is one that consists of two analog metal-oxide field-effect tubes, whose symmetrical, complementary structure makes it just right for handling high and low digital logic levels. However, digital circuits are designed with the goal of being used to process digital signals, and quantization noise can result if arbitrary analog signals are forced in without additional processing.

A function that represents the value of a signal at a discrete set of times is called a discrete-time signal. This is because the most commonly encountered discrete-time signals are analog signals sampled at uniform (and sometimes non-uniform) intervals in time. The terms “discrete time” and “digital” are often used to describe the same signal. Some of the theories of discrete-time signals also apply to digital signals.

Four, how to realize the function of analog and digital circuits

Analog and digital circuits, they are also the carrier of the signal change, analog circuits in the circuit of the signal amplification and reduction of the amplification of the characteristics of the components to achieve the operation, while the digital circuits is the transmission of signals is achieved through the switching characteristics of the operation.

In analog circuits, the voltage, current, frequency, and period of the change is mutual constraints, while digital circuits in the circuit voltage, current, frequency, and period of the change is discrete.

Analog circuits can work under high current and high voltage, while digital circuits just work under small voltage, small current and bottom power consumption to complete or generate stable control signals.

V. Applications

Analog circuits cover almost the entire field of electronics, the implementation of the function of any electronic circuit will involve analog circuits.

Digital circuits and digital electronics are widely used in television, radar, communications, electronic computers, automatic control, aerospace and other fields of science and technology.

### Digital Circuit Basics

Hello, guys! As your senior sister, let me popularize the basics of digital circuits for you. Some of you may find this topic boring, but trust me, once you understand the basics, you’ll be comfortable in the field of digital circuits!

First of all, digital circuits are circuits consisting of digital logic gates that perform various operations such as addition, subtraction, and shifting. There are three basic types of digital logic gates:

The and gate, the or gate, and the non-gate. Their roles are: and gate to realize the “and” logic operations, or gate to realize the “or” logic operations, non-gate to realize the “not” logic operations.

Secondly, the coding methods commonly used in digital circuits include binary code, Gray code and BCD code. Binary coding is a common way of coding values, while Gray code is a special way of coding that changes only one bit in each digit, making it more efficient to use in digital circuits.

BCD code, on the other hand, is a binary encoding method for decimal numbers, which is suitable for dealing with numerical operations and other related tasks.

Also, Karnaugh diagrams are often used for derivation and design in digital circuits. This is a graphical method used for simplification in Boolean algebra, which allows you to quickly find the most simplified logical expression by drawing a diagram.

In short, the basics of digital circuits are somewhat abstract, but understanding them can help you to better design and implement digital circuits, and to better understand how digital devices work. I believe that after my popularization, you already have a clearer understanding of digital circuits!

### What are digital circuits?

The difference between digital and analog circuits is that they are formed in different ways.

Analog circuits are circuits that process analog signals, such as an AC voltage amplified by an operational amplifier to output a larger AC voltage. This is a simple analog circuit. It deals with signals that vary continuously, such as an AC current that is a continuous sine wave.

Digital circuits are circuits that deal with digital signals, in general, the circuit deals with signals that are either 0 or 1, 0 represents a low level, 1 represents a high level. The basic component of a digital circuit is the logic gate circuit.

Difference between digital and analog circuits

Analog circuits are circuits that are used to transmit, transform, process, amplify, measure and display analog signals. An analog signal is an electrical signal that changes continuously. Analog circuits are the basis of electronic circuits, which mainly include amplification circuits, signal arithmetic and processing circuits, oscillation circuits, modulation and demodulation circuits and power supplies.

Modern digital circuits are constructed from a number of digital integrated devices made by semiconductor processes. Logic gates are the basic units of digital logic circuits. Memory is a digital circuit used to store binary data. As a whole, digital circuits can be categorized into two main groups: combinational logic circuits and temporal logic circuits.

Digital circuits use digital signals to accomplish arithmetic and logical operations on digital quantities are called digital circuits, or digital systems. It is also known as digital logic circuits because it has logic operations and logic processing functions.

### What is a digital circuit?

Digital circuits provide a point-to-point data transmission for users using digital transmission links, which can be used for computer networking, data transmission, high-speed Internet access, etc. Digital circuits are suitable for any industry that requires high-speed, real-time transmission of information, especially in the field of communications. Digital circuits are suitable for any high-speed rate, large amount of information, real-time transmission, especially in the field of communications applications, such as multinational corporations, banks, securities, education, websites and so on need to make high-speed transmission industry. It is also suitable for high-speed interconnection between any local area networks and transmission of images such as conference TV.

### What are digital circuits? What are the main characteristics of digital circuits? What is a pulse signal? How to define the amplitude of the pulse

Digital circuits, with the circuit of the on and off or level of the high and low to represent the logic of mathematics in the number of circuits. For example, on means 1 and off means 0. Digital circuits are the basis of modern computers.

Digital circuits are characterized by electrical work in two states, namely saturation (on) cutoff (off).

Pulse signals are non-continuous electrical signals that vary in height. The most commonly used is the rectangular pulse. Pulse by the pulse width and amplitude constitute amplitude is the pulse relative to the zero potential reference potential.

### What is the main topic of digital circuits?

1. A circuit that accomplishes arithmetic and logical operations on digital quantities using digital signals is called a digital circuit, or digital system.

2. It is also known as a digital logic circuit because of its logical operations and logical processing functions.

3. Modern digital circuits are constructed from a number of digital integrated devices made by semiconductor processes.

4. Logic gates are the basic units of digital logic circuits.

5. Memory is a digital circuit used to store binary data.

6. As a whole, digital circuits can be categorized into two main groups: combinational logic circuits and temporal logic circuits.

7. Digital circuit design, is a part of hardware design.