PCB Technical - PCB circuit board and integrated circuit analysis

The current PCB circuit boardmainly consists of the following:

Circuit and pattern (Pattern): The circuit is used as a tool for conduction between the originals. In the design, a large copper surface will be additionally designed as a grounding and power layer. The route and the drawing are made at the same time.

Dielectric layer (Dielectric): used to maintain the insulation between the circuit and each layer, commonly known as the substrate.

Hole (Through hole / via): The through hole can make the lines of more than two levels connect to each other, the larger through hole is used as a part plug-in, and the non-through hole (nPTH) is usually used as a surface mount It is used for fixing screws during assembly.

Solder resistant /Solder Mask: Not all copper surfaces need to be tin-on parts, so the non-tin area will be printed with a layer of material that insulates the copper surface from tin-eating (usually epoxy resin), avoid Short circuits between non-tinned circuits. According to different processes, it is divided into green oil, red oil and blue oil.

Silk screen (Legend /Marking/Silk screen): This is a non-essential composition. The main function is to mark the name and position frame of each part on the circuit board, which is convenient for maintenance and identification after assembly.

Surface Finish: Since the copper surface is easily oxidized in the general environment, it can not be tinned (poor soldering properties), so it will be protected on the copper surface that needs to be tinned. The protection methods include HASL, ENIG, Immersion Silver, Immersion TIn, and OSP. Each method has its advantages and disadvantages, which are collectively referred to as surface treatment.

PCB board features

Can be high-density. For decades, the high density of printed boards has been able to develop along with the improvement of integrated circuit integration and the advancement of mounting technology.

High reliability. Through a series of inspections, tests and aging tests, the PCB can work reliably for a long time (usually 20 years).

Designability. For PCB performance (electrical, physical, chemical, mechanical, etc.) requirements, printed board design can be achieved through design standardization, standardization, etc., with short time and high efficiency.

Manufacturability. With modern management, standardized, scaled (quantitative), automated and other production can be carried out to ensure product quality consistency.

Testability. A relatively complete test method, test standard, various test equipment and instruments have been established to detect and appraise the eligibility and service life of PCB products.

Can be assembled.PCB products are not only convenient for standardized assembly of various components, but also for automated and large-scale mass production. At the same time, PCB and various component assembly parts can be assembled to form larger parts and systems, up to the complete machine.

Maintainability. Since PCB products and various component assembly parts are designed and produced on a large scale, these parts are also standardized. Therefore, once the system fails, it can be replaced quickly, conveniently and flexibly, and the system can be quickly restored to work. Of course, there can be more examples. Such as miniaturization and weight reduction of the system, and high-speed signal transmission.

Integrated circuit characteristics

Integrated circuits have the advantages of small size, light weight, few lead wires and soldering points, long life, high reliability, and good performance. At the same time, they have low cost and are convenient for mass production. It is not only widely used in industrial and civilian electronic equipment such as tape recorders, televisions, computers, etc., but also in military, communications, and remote control. The use of integrated circuits to assemble electronic equipment can increase the assembly density by tens to thousands of times compared with transistors, and the stable working time of the equipment can also be greatly improved.

The difference between PCB board and integrated circuit

Integrated circuits generally refer to the integration of chips, like the north bridge chip on the motherboard, inside the CPU, they are all called integrated circuits, and the original name is also called integrated block. And the printed circuit refers to the circuit board we usually see, as well as printing solder chips on the circuit board.

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The integrated circuit (IC) is soldered on the PCB board; the PCB board is the carrier of the integrated circuit (IC). The PCB board is a printed circuit board(PCB).

Printed circuit boards appear in almost every electronic device. If there are electronic parts in a certain device, the printed circuit boards are all mounted on PCBs of different sizes.

In addition to fixing various small parts, the main function of the printed circuit board is to electrically connect the upper parts to each other.

Simply put, an integrated circuit integrates a general-purpose circuit into a chip. It is a whole. Once it is damaged internally, the chip is also damaged, and the PCB can solder components by itself, and replace the components if it is broken.