Introduction to pcb board assembly and its role in major Industries
Pcb assembly china is playing a vital role in making long pcb boards. Long pcba board manufacturers use it in various electronic devices such as:
- personal computers
- automobiles and car navigation systems
Long pcb boards are an essential component of electronic devices. Although the printed circuit board itself is relatively common, it is important to know:
- What role the board itself plays?
- How it is made?
- Who designs electronic circuits, etc.?
“ Even though printed circuit boards are very familiar, very few people know the reality.”
This article introduces various information and knowledge related to the pcb board. Similarly, it is a comprehensive pcb board guide that will also include information about long pcb. If you are really interested in knowing more about the classification of printed circuit boards, this piece of writing is going to help you a lot.
Basically, leading pcb board manufacturing companies to classify printed circuit boards on the basis of its functions and result. But typically, we can divide into three classes.
Q. On which bases the PCBボードメーカー classify printed circuit boards?
Generally, printed circuit boards have classification on the bases of its operations, usage, and applications.
- High-reliability boards
Q. What is the consumer PCB board?
Generally, the consumer PCB board is very common in day to day electronic devices. Moreover, consumers’ products are like TVs, smartphones, and touch screen devices. Therefore, this equipment has high resisting material and low cost to meet the consumption rate. For instance, for a consumer, he has a lot of options to buy gadgets. Because there are a variety of boards available in the market. One can go for low cost and expensive devices depending on the budget. Subsequently, the consumer pcb board is a great choice of small scale companies. In addition, they are cheap and effective in performance. Moreover, these boards offer easy customization.
Q. What are professional printed circuit boards?
Bigger equipment has long pcb board integration. Therefore it should have better quality and better material to meet the market demand. Moreover, it has a strong foundation. It helps any device to perform at the highest peak. By every passing day, huge machines are coming into the market. Furthermore, these machines require long pcb boards for working properly. To maintain the performance, pcb board manufacturers have developed extremely good long pcb boards. They have multilayers and powerful bases that support an extreme working environment.
Q. What is the high-reliability pcb board?
This pcb board has high-grade materials. In addition, it has controlled and planned processes. The high-quality material used on the base of this board gives effective functionality.
These devices have multi-functional. For instance, recorders, disks, digital cameras, and other cam recorders are now become more complex, advance as well as in demand.
Different new pcb board & long pcb board technologies are in the market now:
- like mounting and automatic fabrication of プリント基板
- making the board more miniature
- building small size boards with improved functionality
Classification of long pcb board
Classification of a pcb board depends on
- Number of planes on the board
- Layers of wiring on the board
- Constitution and assembly of wiring
- The existence of plated-through holes
Due to this classification circuit boards have become prominent. Similarly, anyone can select it easily. For instance, if you need a specific pcb board, the classification will help you.
How Many Types of long pcb board?
Here are the types of circuit boards according to the construction classification.
- Single-sided PCB
- Double-sided PCB
- Multi-layer PCB
- Rigid and flexible PCB
Single-sided Printed circuit boards
The board which has wiring on the single side of the insulating substrate is known as single-sided PCB. It is a single layer board and a low-density board.
Solder side; the side of the board which has wiring (circuit pattern) on it
Component side; the side other than solder side
Use: Pcb boards manufacturers use it in simple circuits..
- The manufacturing cost is less on the single-sided board
- These boards provide a facility for both professional and non-professional means
- Similarly, PCB board manufacturers use ‘print and etch’ method or by ‘diecut’
Generally, the die-cut method is very common to print or draw the wiring pattern on the board by a photoengraved machine.
Pcb board manufacturers can avoid mistakes on this kind of board. That is why it is a low-cost board. Furthermore, the holes have a soldering option on both sides of the PCB. While designing this kind of board the soldering joints have less placement to make the removal of components easy. Subsequently, the components on this board are more likely on the solder side and the rest of the components are on the component side.
The long pcba board manufacturers place lead wire around through-hole and then securely solders to the pads on both sides. Moreover, the double-sided boards use different eyelets on both sides of the board.
Multi-layer PCB board
The multi-layer board has more than two layers. The technology of plated through-holes and cross-over planes, reduction of space, increased density lead to a reduction in the conductor. Similarly, the material between layers of the multi-circuit board is ‘prepreg’
Q. Why multi-layer PCB boards?
There are problems such as noise, cross-talk, voltage drops, etc. on the complex design PCB. That is why multi-layer boards have the ability to overcome all the problems that are almost impossible in a single layer board.
Features of multilayer long PCB board
The pcba board has a close connection of layers. The layers are connected through plated holes. The multilayer board has as many as 50 layers. Furthermore, this board is lightweight and less space-consuming as compared to other boards.
The proper arrangements of wires and spaces are necessary while fabricating boards. This is difficult because the boards have many materials to be soldered. In addition, the shielding and twisting of a large number of wires are important. Simultaneously, the multi-layer boards have number of layers that is why the shielding of wires is done on internal layers and the soldering is satisfactory and the thick layer of copper in on the outer layer.
- The cost and budget of these boards depend upon the technology and the complexity of components
- The multilayer board can minimize the problems faced while heat removal.
- Moreover, four-layered and six-layered boards have easy mass lamination techniques.
Advantages and application
- Multilayer boards are more reliable
- Less costly
- A lot of industries use this board like the toy industry and much other electronic equipment.
Rigid and Flexible Printed circuit boards
According to the board characteristics, pcba board manufacturers use them in electronic devices
- Rigid; it has a variety of material on the board
- Flexible; flexible materials like polyesters or polyamide are used. Simultaneously, the thickness of the base is 0.1mm. Copper laminates are used in these boards. They may be single-sided and double-sided as well.
- Rigid-flex; The fusion of rigid and flexible board collectively form rigid-flex boards. The arrangement of two boards gives volume and a 3D structure. This board is commonly used in many electronic devices.
Manufacturing of basic PCB board
The fabrication process basic steps of boards are almost the same and almost primary steps the same. Furthermore, to improve the quality and yield of the boards, steps may vary. ‘Print and etch’ is the subtractive method that is widely used while manufacturing the circuit boards.
What is Print and etch?
This is a method printed circuit board manufacturers use while processing circuit boards. The base is copper laminated and all the components are soldered on it, a layer of etched metal tracks make connections are used. Simultaneously, this method prints the design of wiring on the laminated base.
Specific phases of long Pcba board
The specific phases for the manufacturing of circuit boards areas
PCB is going more complex day by day with developing design and verification processes.
Here are the simple steps which describe the process and fabrication of single-sided circuit boards.
A schematic diagram represents the components, system and all connections in a diagrammatic or picture form. Furthermore, it is also famous for the circuit diagram or logic diagram. Examining the following things schematic diagram is formed
- Defined components
- Interaction of components
- Physical packages
- Array and alignment of pin-out
Q. How to from circuit diagram for PCB board?
The diagram is printed on paper and then on CAD. The diagram shows all the labels on the print e.g. pin numbers. At last, the print on the paper and print on CAD combine and relate together. And a circuit diagram forms the main step of designing will start.
Artwork generation of PCB board
- PCB layout
The circuit diagram has a basic function to deriving the PCB layout. The circuit diagram is placed and routed to get proper sized board. The PCB layout describes the labels of the board.
2- Track layout
After the PCB layout, track layout forms itself on self-adhesive such as polyester.
Generally, the layout is actually four times large for better quality checks during examination but then the artwork is reduced to the actual size of the board.
4- Panel preparation
The single-sided board has wiring on one side, one-sided copper laminated board is the raw material for the preparation. The laminated sheets are then cut into slightly large strips. The size of the strips kept 350 ¥ 508 mm.
General lamination is paper-based and the lamination used for superior and mechanical properties is epoxy glass lamination.
Q. What are the Mechanical and electrical properties of the PCB board?
The mechanical properties are
- The quality of punched and drilled holes
- Flexural strength of the material
- Flame resistance or thermal control
- Absorption of moisture
The electrical properties are
- Dielectric strength
- Dielectric constant
- Dissipation/impurity factor
- Resistance of insulators
- The resistivity of volume and surface
- Base material
- Thickness;6 mm
- Cladding; the copper foil cladding is 1 oz. /square ft. (305 g/ m2)
- The thickness of foil;35 micron
- Contaminants Before processing the board must be free from contaminations. Above all, the contaminations on the copper foil may be oil, grease, dust, particle oxides and sulfides. The boards are then cleaned with scrubbing agents and by brushing and acid wash.
How to transfer an image on the Pcb board?
A further process is transferring of the print on the card. Similarly, the layout or artwork is maybe a positive or negative photographic film.
- Photographic film itis a transparent polyester film.
- Thickness; 7 mils (174 microns) Silver halide emulsion on the film is 4-8 micron thick.
- Sensitivity; 480-550 nm wavelengths Processing of fill is done in the red light. During etching, all the conductive areas are covered with the screening ink which acts as an etch resist. The process is carried out in the machine known as a laminator.
Types of photoresist
Positive photoresist; the polymerize resist in this case is developer soluble
Negative photoresist; the polymerize resist is developer insoluble. This polymerization occurs under UV rays
Etching: The removal of unwanted copper from the board is known as etching. It is the basis of the whole process. It involves different methods.
Etchant; ferric chloride, ammonium persulphate, chromic acid, cupric chloride, alkaline ammonia
The areas on the board which does not have protection by etching resist, this etchant react there and oxides copper to cuprous chloride.
Methods: Methods of etching are immersion, bubble splash or spray.
Q. What is spray etching?
Spray etching is the method through which the etchant has spray option from the nozzle of the tank with a pressure. Similarly, the etchant slashes all over the board
Board drilling of PCB board
Generally, there are several methods to drill the board with respect to the types of the board such as drilling through single head drilling machines, laser drilling, etc.
- On a small scale, the boards are drilled with a drilling machine of a single head.
- Jigsare there to check and verify the size of the holes and missed holes.
- To drill the layers of boards in once the boards ate stacked and drilled.
- The drilling of boards can be done with multi-headed drillers also.
The long PCB boards are growing vastly in the electronic technology and thus the boards are getting smaller in weight and size. The diameter of the holes on the boards is also getting smaller with blind VIAs. So proper method of drilling requires decent printed circuit boards. For instance, tungsten carbide drilling or drilling with a diamond-tipped head. Above all, drilling is best for fiberglass boards.