PCB classification

According to the circuit layer classification: divided into single panel, double panel and laminated. Common sandwich plate is commonly 4 layer board or 6 layer boards; complex sandwich plate can reach dozens of layers.

1. Single – Sided PCB

Single panel (Single - Sided Boards) in the most basic on the Aluminum pcb of parts on one side, the conductor is focused on the other side (have SMT components with lead to one side, the plug-in device to the other side).Because the wires in only one side, so this kind of PCB is called Single panel (Single sided).Because single panel in the design of lines, there are many restrictions (because only one side, wiring must around the path alone cannot cross between), so only use this kind of early circuit board.


2. Double - Sided PCB
Double panel (Double - Sided Boards) to both sides of the circuit board wiring, but it took two wires, must have the appropriate circuit connection between two sides. This circuit is called the "bridge" between the guide hole (via).Guide hole is on the PCB, or coated with metal small hole, it can be connected to both sides of the wire. Because the area of the double panel a times larger than a single panel, double panel solved because wiring of the difficulty in the single panel (can be conduction through the hole to the other side), it is more suitable for use in more complex than a single panel circuit.

3. Multi - Layer PCB
Sandwich plate (Multi - Layer Boards) in order to increase the area of the wiring, a multilayer wiring board using the more single or double. With a double lining, two one-way for outer layer or two double lining, two blocks of single outer layer of the printed circuit board, through the positioning system and alternate insulation adhesive materials and conductive graphics interconnection according to design requirement of printed circuit board becomes four, six layer printed circuit board, also known as multilayer printed circuit board. Layer number of the board does not mean that there are several independent wiring layer, under special circumstances will join empty layer to control board thickness, layer number usually is even, and contains the outer two layers. Most of the motherboard is 4 to 8 layer structure, but technical theory can be nearly 100 layers of PCB. Large supercomputers are used quite layers of the motherboard, but because this kind of computer can replace with many ordinary computer cluster, super sandwich plate has not been used gradually. Because each layer of PCB are closely combined, the actual number is generally not too easy to see, but if you look closely at the motherboard, can still see it.

PCB Board and Its Advantages to the Industrial Setups 1----Wonderful PCB(hk)Limited

In a very shortest time frame, PCBs or printed circuit boards have turned as the most sophisticated tools used in the electrical equipment domain. In such the competitive market place, importance and gravity of the printed circuit boards can’t be ignored. A PCB or printed circuit board contains highly advanced chips. These applications are placed a very slim plate for some of the components. Manufacturer and developing PCB boards is certainly a tough job that requires massive presence of mind, highly skilled knowledge base and awareness of latest technologies as well.

If experts are to be believed, PCB is an essential device used in almost every industry irrespective of capital, size or strength. A single fault in PCB boards may lead to the big damage and major loss the industry. You may get a number of instances of the PCBs across you. The perfect instance of PCB is motherboard, controller board and different kind of interface cards.

These PCBs have crafted a very special market place in the market and its growing demands are now being fulfilled by numerous manufacturers in the industry.

There are three primary elements of a Printed circuit board namely a laminate board, components mounted on the board and the traces that serve as the wires. The use of actual components in the circuit board is entirely depends upon the purpose and intention of the circuit. Elements used in the PCBs play significant role in finding the Production costs, working efficiency and operating cost of the PCB circuit.lectric layer, a layer of silk screen will be printed. Some words will be printed to show the position of those components. It is also called legend.
PCB finishing
PCB Surface Finishes vary in price, availability, shelf life, reliability and assembly processing. While each finish has its own benefits, in most cases, the process, product or environment will dictate the surface finish that is best suited for the application. It is recommended that the end-user, designer or assembler work closely with their PCB supplier to select the best finish for the specific product design.
If need any more information on PCB, you could check and source from this website: http://www.wonderfulpcb.com Wonderful PCB Technology Co., Ltd is a professional PCB manufacturer for many years and could try best to help!
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Ms. Jodie Zhou
Wonderful PCB
T +86-755-86229518-807 | F  +86 755 2607 3529|  e  wonderful09@wonderfulpcb.com |
www.wonderfulpcb.com | Skype: wonderful-02   | MSN: wonderfulpcb06@hotmail.com
Welcome to our trading shows:
1. Booth:  L32, Expo Electronics 2013, Apr.10-12th in CROCUS EXPO, Moscow, Russia
2. Booth: 11J36, HK Global sources Apr.12-15th, 2013 Asia World-Expo, and Hong Kong
3. Booth: 9J35, HK Global sources Oct.12-15th, 2013 Asia World-Expo, Hong Kong

Wonderful Printed Circuit Board

1) Single layer PCB:
   Single-sided printed circuit board is very normal and easy PCB board. The components is a side and the circuit line in the other side, that means there is only one circuit so also named 1layer PCB or single layer printed circuit board. There is having strict limited for single layer PCB design.Because only one layer circuit for the whole design so the Flexible pcb line can not crossover. Besides, the one layer PCB is also very easy to make mistake, such as the solder mask layer, some customers need only one layer solder make, some customers need double layers solder mask.
2) Double layer PCB:
Double layer PCB occupy about 60% of the PCB market.Double-sided printed circuit board as having two layer circuit line so called two layer PCB or two layer circuit board. There are two side circuit lines top and bottom, we also say two copper side. Needing a bridge or a guide line to make the top and bottom circuit connect, we called this via. Via holes in the PCB board which is plated hole. The via hole can connect the top circuit and bottom circuit, this solve the problem of circuit connection and make the double layer PCB twice bigger then single printed circuit board. This is much better then one layer PCB and avoid a lot of problem.
3) Multilayer PCB:
  Multilayer printed circuit board can increase the size of circuit line. The multilayer circuit board make up of one double layer to make inner layer and two single side printed circuit board to make out layers or two double sided circuit board to make inner layer and two one side PCB to make out layers. Through via holes and insulating material to make the circuit connect so that every layer can be a whole system. Besides the layers can not indicate the independent layers, some times also have blank layer which without circuit to control the thickness. The capability we can do is from 4layer up to 28layers.
Sophie Deng
_______________________________________
Wonderful PCB Limited
NO.32A,Building NO.1, XianDaiC hengHuaTing,ChuangYeRoad|NanShan District,ShenZhen City 518054|  China  T +86-755-86229518-806 | F  +86 755 2607 3529|  e  wonderful08@wonderfulpcb.com |
w  www.wonderfulpcb.com  | Skype:wonderful-07   |                                                  
Welcome to our trading shows:
1.Booth: L32,Expo Electronic 2013,Apr.10-12th in CROCUS EXPO,Moscow,Russia
2.Booth: 11J36, HK Global sources  Apr.12-15th, 2013 Asia World-Expo, Hong Kong
3.Booth: 9J35, HK Global sources Oct.12-15th,2013 Asia World-Expo, Hong Kong
4.Booth: 70206, CES  2014  Jan,8th-11th in Las Vegas, USA

PCB Layer Introduction

PCB Signal Layer
The signal layer is mainly used to be placed with the object associated with the signal, which is divided into top, bottom and middle layer . Typically, the top and bottom to place the components and wiring ; intermediate layer is mainly used for the wiring operation.

PCB Power / ground layer
Power / ground layer is mainly used to place the power and ground lines , power and ground circuit components power and ground pin does not need through any copper mold wire connected directly to the power supply and ground lines , and avoid some of the the emergence of design issues , such as ground loop interference.

PCB Mechanical Layer
The function of Mechanical layer is that this layer mainly used to describe the mechanical structure of the Multilayer pcb and place the label instructions, no specific electrical connection characteristics . For example , the mechanical layer may be used to define the physical boundaries of the circuit board in order to avoid Component placed outside the physical boundaries

PCB Mask Layer
The protective layer can be divided into two categories: Solder Mask layer and flux ( Paste Mask ) layer. Solder resist layer is used to protect the copper wire and to prevent the components are soldered to the right place , this layer commonly known as green ink. Generally, the surface of PCB board all covered with solder mask except the place where has pads. In this way to prevent the PCB surface soldered with tin. The flux layer is used to improve pad solderability characteristics. On PCB, the light-colored circular spot which is a little bigger than pad we usually see is the flux layer.

PCB Silkscreen Layer
Silkscreen layer is used to identify the specific location of the various components on the PCB, for example, the components package outline appearance and character , the purpose is to bring convenience to circuit installation and maintenance . Typically , white legends and symbols on the PCB is the silkscreen what often mentioned by human. In PCB field, silkscreen include includes components location , the nominal value , the outer contour of the components and manufacturers logo , production date and so on.

Flying Probe test

Flying Probe test is to test some of the major problems of electrical latest solutions. To replace it with a probe needle bed, a plurality of motor-driven can quickly move the probe with the electrical devices of the pin contact and electrical measurements. This instrument was originally designed as a bare board, also requires sophisticated software and program support; has now been able to effectively simulate the online Aluminum pcb test. Flying Probe Test appearance has changed the test method and the low yield rapid conversion (quick-turn) assembled products. Used to take weeks to develop a test a few hours now, and greatly shorten product design cycles and time to market.

Rapid test development; low cost test methods; flexibility fast conversion; well as in the prototype stage to provide rapid feedback to the designer. Therefore, comparing the traditional ICT, Flying Probe test by reducing the time required to make up for the total test time. Flying Probe test system using the benefits outweigh the disadvantages. For example, during assembly, such a CAD system file received after the start of production hours. Therefore, to test the prototype circuit boards for several hours after assembly, not like ICT, high-cost test development process and fixture may be delayed a few days or even a few months. In addition, due to the simple and quick setup, programming and testing, in fact, the general assembly of technical personnel, and not an engineer, you can operate the test. Flying Probe test also exist the flexibility to do a quick test errors quickly convert and process feedback. Also, because the test does not require flying fixture development costs, so it is a typical testing process can be placed in front of the low-cost systems. And because Flying Probe Tester change and rapid test method to convert low-yield assembly, testing usually takes a few weeks to develop a few hours you can get now.

Automatic optical alignment system and the traditional combination of flying machines, the entire automatic optical alignment can make flying more convenient testing and flying in the image processing software dedicated to digital cameras with the help of more accurate. In the traditional Flying Probe test machine, the installation of Flying dedicated to digital cameras and the corresponding image processing software; flying probe testing throughout the automatic identification and detection of the corresponding position to make flying safe and fast test. Having regard to the requirements for fast and precise flying machine, solid industrial hardware and graphics hardware choice, you should first take into account the lightweight, industrial, optical distortion-free, high-speed image processing algorithms; such testing in the actual process of flying because the industry does not appear to affect the hardware itself, the weight of the test accurate, does not appear lost step, and does not affect the image processing algorithm speed flying probe test.

The characteristic and kinds of PCB surface finishing

As for human living environment asks is ceaseless rise, currently involved in the process of PCB production environment problem is particularly prominent.At present about lead and bromine is one of the hottest;Utilizing and halide will influence the development of PCB board in many ways.Although for now, the change of the PCB surface treatment technology and is not very big, still more distant things like, but should notice: long-term slow change will result in great changes.In the case of environmental protection calls for more and more high, the surface of the PCB process changes will happen in the future.
Surface treatment for the purpose of surface treatment of the most basic purpose is to guarantee good weldability or performance.Due to the nature of copper in air tend to exist in the form of oxide, is unlikely to keep to the original copper for a long time, so you need to other copper processing.While in the later assembly, strong flux can be used to remove most of the copper oxide, but strong flux itself is not easy to remove, so the industry generally don't use strong flux.
Common five kinds of surface treatment technology now has a lot of PCB surface treatment technology, common is hot air leveling（HASL), organic coating, electroless nickel/immersion gold(ENIG), immersion silver and tin the five kinds of craft.Because the PCB production  and material cost and process, so the different pcb design will use the different surface finishing. The cheap electronics  and simple products, we will use HASL or OSP, but for the expensive and high-density electronics products, we will use the immersion gold or silver, the pcb cost will higher, but it will better for components assembly.

Through Hole and SMT

Through Hole Mounting: This mounting technique involves different components which have lead wires that are led to the board through holes, hence the name. In this method, leads rely on holes in a multilayer PCB. The leads are then finally soldered to offer permanent mounting. The technology finds usage in DIP aka Dual Inline Packaging and Pin Grid Array Package. 

Surface Mounting: This is a relatively new mounting method worked out seeing a tremendous increase in the number of pins in Integrated Circuits. As demand for smaller weight and size of packaged weight increased, there was felt a need for a new, improved technology that came to be known as surface mount technology (SMT). In this leads are soldered on PCB surface directly rather than using hole mounting. The technology is used in Flatpack Packages and Chip Carrier Packages.

There are some points that make SMT different from Through Hole, which have been briefly summarized below: 

1.SMT has helped significantly in solving the space problems that were commonly noticed with the Through Hole mounting.

2.The pin count has increased greatly in SMT when compared to its older counterparts.

3.In SMT, the components are leadless and are directly mounted to the board surface. In Through Hole the components have lead wires that are taken to the wiring boards via

holes. 

4.The Pads on the surface in SMT are not used for connection of layers on the printed wiring boards.

5.The components in the Though Hole Technology are larger which leads to lower component density per unit area. The packing density that can be achieved with SMT is very high as this allows mounting component on both sides, when needed.

6.SMT has made possible applications that seemed impossible with through hole.

7.SMT is suitable for high volume production that gives access to lowered cost of unit assemblies which is not possible with through hole technology.

8.With SMT acquiring higher circuit speed is easier due to the reduced size. SMT fulfils one of the prime marketing requirements while assisting in making high performance Rigid-flex pcb in a very small size.

9.SMT has a disadvantage as the capital investment involved in its machinery and production is higher.

10.Designing, production, skill and technology required in implementing SMT is very advanced when compared to through hole technology.

When comparing both, SMT surpasses Through Hole in advantages, which clearly define and justify the majority (90%) use of this technology in board assemblies. Through Hole however is anticipated to remain in use in testing and prototype applications that may need manual adjustments and replacements. Its complete disappearance from the scene seems to be ruled out.

When you should need PCB Assembly

Although your electronics business has been doing fine on its own for awhile, there comes a point in every smaller company's life when it must decide whether or not to enlist the help of third party services in order to meet customer demands or to reach goals. As you weigh the costs and benefits of working with a PC board assembly company, however, you may find it difficult to know what will be best for your business. To make your decision easier, here are three situations in which contracting with a PCBA manufacturer should be seriously considered.

1. You need to develop small, highly complex products
Assembling efficient and effective PCBs for today's small, lightweight electronic devices is nothing to scoff at. With technology shrinking, it only becomes more difficult for contract electronic manufacturers to develop and produce PC boards that will fit the bill. If your company is unable to afford the costs associated with advanced, state-of-the-art assembly machinery, you may be finding it very difficult to keep up with consumer demands. Older, clumsier machinery may struggle to print circuits to the board in a way that is accurate and precise. Ultimately, this can result in faulty products, lost money as you are forced to throw out boards where the circuit was not properly etched, and can make the assembly process take far longer than it should. Once this step is completed, you must have the ability to carefully and skillfully drill holes into the board in order to accommodate all of the necessary design components.
Without new, properly maintained machinery, the likelihood for expensive errors will increase significantly. If this sounds all-too familiar, it is time to consider working with a PC board assembly company that can take on these burdens for you. With the latest automatic machinery, robotics, and extremely talented and experienced technicians, even the smallest and most detailed PCBs can be manufactured with accuracy.

2. You're looking to reduce time and costs
Time is money, which means that speed is a must in terms of cost-efficient and success. The more time it takes you to produce PC boards, the more you must charge your customers. If the costs grow too high, your clients will turn elsewhere. The problem is that without the ability to assemble your devices fast while still maintaining a high level of quality and precision, you will find yourself falling behind. The best and most economical way for smaller companies to resolve this issue is to contract with a PC board assembly company. With the help of a team of professional designers, engineers, and manufacturers, you will be able to turn out products that are efficient, effective and highly functional in a fraction of the time and for less capitol.

3. You're hoping to grow
The goal of any business is to grow and thrive, but unless you're able to produce fast, quality, and competitively priced PC boards, you're going to end up being stuck in the same place for awhile. Your company may have the ability to produce very small quantities of your products, but in order for you to take on larger clients and increase your profits, you need to be able to keep up with larger orders. Often, the "little guys" get stuck in a "Catch-22 situation" wherein a large client places a large order. If you're paid for the large order, you can afford to hire more help or purchase new equipment, but you can't get paid until you produce quality PC boards. Unfortunately, you can't produce the boards, because you don't yet have the manpower or machinery required. To get yourself out of this rut, you can work with a PC board assembly company that will enable you to produce more PCBs in less time so that you can fulfill purchase orders and finally grow.

Knowlage Of Printed Circuit Board

Author:Sophie
     Electronic products function depends on the correct interconnected electronic components, most of these components are interconnected based on the circuit board welding. Circuit board welding in the assembly of electronic products, has been playing an important role. There are many connections even if the current technology, but the circuit board welding remained dominant.
     Circuit board welding is an important part of electronic technology. Proper design and good solder process (ie, circuit board soldering process), is the key factor for reliable soldering. The so-called "reliable" refers to all the properties of the solder joints only when the product has just produced as required, but also throughout the life of electronic products, and should be guaranteed to work correctly.
     Although all of the physical-chemical principles of welding process is the same, but for soldering electronic circuits and has its own characteristics, i.e., miniaturization and high reliability, which is consistent with the characteristics of electronic products. Circuit board welding quality will be affected by many factors. Funds such as the type of material and its surface is, the type and thickness of the coating, processing technology and methods, surface condition before welding, soldering components, welding, soldering temperature and time are base metal welding gap size, flux type and performance, welding tools. Important reason for not being among the internal structure of the metal oxides and lead solder components lead compounds the situation is affecting the surface leads solderable, but also affect the surface of the oxide Flexible pcb pad solderability main reason.
     Using tin-lead soldering tin-lead solder is called, referred to soldering, the mechanism is: will solder in the solder process, weldment and copper under the action of heat welding, weldments and copper does not melt, the solder is melted and welded surface wetting rely weldments asked two copper atoms and molecules to move, thereby causing diffusion between the metal and the weld is formed between the copper alloy layer of a metal member, and to connect the copper foil and the weldment together, they get solid and reliable solder joints, the above process is the role of the physical-chemical processes each other.
    When the solder and welding weldment joint is heated to welding temperature, melting the solder does not melt weldment. Forming welding solder wetting rely molten state welding surface, resulting in the metallurgical, chemical reaction to form a bonding layer, to achieve a combination of the weldment. Lead-tin solder melting point below 200 ℃, suitable for connecting semiconductors and other electronic materials. Simply heating tools and materials can be processed, less investment. Joints have sufficient strength and electrical properties. Soldering process reversible, easy desoldering
Sophie Deng
_______________________________________
Wonderful PCB Limited
NO.32A,Building NO.1, XianDaiChengHuaTing,ChuangYeRoad|NanShan District,ShenZhen City 518054|  China  T +86-755-86229518-806 | F  +86 755 2607 3529|  e  wonderful08@wonderfulpcb.com |
w  www.wonderfulpcb.com  | Skype:wonderful-07   |                                                  
Welcome to our trading shows:
1.Booth: 9J35, HK Global sources Oct.12-15th,2013 Asia World-Expo, Hong Kong
2.Booth: 70206, CES  2014  Jan,8th-11th in Las Vegas, USA

About WonderfulPCB Tech Limited

WonderfulPCB Tech Limited was found in 1996, it provides professional Aluminum pcb,Flexible pcb,Rigid-flex pcb,Multilayer pcb,PCBA manufacturer service for over than 1500 customers around the world. In order to satisfy more and more customers requirement about lead time and price, Our PCB built its own assembly factory in April 2011
Our PCB's Assembly factory is equiped many advanced machines, e.g. Siemens HS50 placer, Siemens F5 Placer, Heller 1809 Reflow,Speedline MPM printer,OK intelligent solder iron,Otek Automatic Optical Inspection... we can assemble BGA,LGA,QFN,QFP,DIP,SIP...., The smallest package form we can mount is 0201. Our factory also can provide programming,wiring, screwing, injecting and conformal coating service. It have ISO9001 Certification
For bare PCB manufacture, Our PCB is an important partner of Shenzhen Uniwell Circuits Co., Ltd, which have two PCB manufacture factories now, Uniwell have ISO9001, ISO14001,TS16949,UL certifications
Our PCB VISION
Be the most reliable PCB and PCBA service supplier
Our PCB MISSION
Dedicate to satisfy customers' needs.
Provide high quality products
Provide most professional services.
Deliver products on time.
Keep all costs to minimum and maximize our customers' benefits.