Gold plating for Gold fingers of Printed Circuit Board

Gold fingers also called edge connectors, normally used in plugged in. Wonderful PCB Limited offer two types of gold finish: Electroless Nickel Immersion Gold (ENIG) as a surface finish for the whole PCB, and hard plated gold over plated nickel for edge-connector fingers. Electroless gold gives excellent solder ability, but the chemical deposition process means that it is too soft and too thin to withstand repeated abrasion. Electroplated gold is thicker and harder making it ideal for edge-connector contacts for PCB boards which will be repeatedly plugged in and removed.

Normally We plate the hard gold onto the PCB boards after the solder mask process and before we apply the surface finish to the rest of the board. Hard-gold plating is compatible with all the other surface finishes we offer. We first plate 3 – 6 microns of nickel onto the edge connector fingers and then on top of that 1 – 2 microns of hard gold. The plated gold is not 100% pure; it contains some cobalt to increase the wear-resistance of the surface. We normally bevel the edge connectors to ensure easy insertion. Beveling can be specified in the order details.

To make sure that the gold fingers exactly the same as the edge-connector profile, we rout the vertical edges of the connector on the first drill run. In some cases one or more gold fingers are shorter than the rest, so that the longer pads connect first when the PCB inserted into the connector. This means that the shorter pads cannot be connected vertically to the plating bar. They have to make the connection needed for electroplating in another direction

Below is the some of the PCB boards with gold fingers for your reference:
       

For more about us, please visit us at: www.wonderfulpcb.com. If you have any inquiry, please feel free to contact Stephen Zeng at email: wonderful15@wonderfulpcb.com. Thanks.

Fiducial Marks Of Printed Circuit Board

Fiducial marks are required for the automated placement of all SMT components. They are used as reference points by Auto placement machines to establish XY co-ordinates for accurate component placement.

1)There must be 2 fiducals placed diagonally opposite each other (on two diagonal corners of the PCB boards if possible) See Figure 5 below.

2) Fiducials should be created as a part in the component library, it will then appear in the pick and place data with a reference and XY co-ordinates.

3)Must be round and with a diameter of 1.5mm. A clear area of 2mm around each fiducial is required. See FIGURE 6 below.

Panelization requirement:

Optimum panel size (preferred): 150mm x 250mm including break off areas.

Maximum panel size: 250mm x 320mm including break off areas.

We can accommodate this size as a special case but quality problems due to this size may affect final yield.

PCB Number:
PCB must have a particular part number which must include the following:

1) Customers PCB number.
2) Version number. First version will show as V1 for example. (See below)


The above constraints should be met by the PCB design Engineer before Gerber, CAD and Pick and Place data is issued.

For more about the PCB production, please feel free to contact us by email wonderful15@wonderfulpcb.com .Thanks.

PCB Reverse Engineering

Wonderful PCB Technology Co., Ltd. is a professional PCB manufacturer and exporter located in Shenzhen, China. We provide PCB prototype, Rigid PCB, FPC, Rigid-flex PCB’s mass production. Also, we could support PCB reverse engineering from your PCB sample. More information, please check our website: www.wonderfulpcb.com

In the end of 20 century, the developing of technology was flourishing in Western countries and various advanced electronic products emerged. These electronic products were widely used. The developers mastered nearly all the technical programs and monopolized the field for such products. As a result, some enterprises raised the prices of their products maliciously so as to achieve greater profits. In order to break this monopoly, someone tried to copy such products with reversed research and analysis. Then the PCB reverse engineering emerged.

When the technology of PCB reverse engineering merged in the first stage, this technology is only confined to simple copying and cloning of the circuit board. However, nowadays, PCB reverse engineering also involved in the secondary development of products and new design/ new product development. When you reverse Engineer something, you should fully understand the design including impacts on timing, etc. There are designs out there with specifically designed center planes designed to impact data flow through the board. Some designs even have their own internal tuned coax etched into inner layers. For example, through the analyzing of product technical documents and comprehending of design ideas, structural features and technology, PCB reverse engineering can offer analysis of feasibility and competitive reference for the development of new products so as to help the R & D units to follow up the latest technology trends, adjust and improve the product design and produce the most competitive new products.

At present, the miniaturization of electronic products continues to drive printed circuit board manufacturing towards smaller and more densely packed boards with increased electronic capabilities. Advancements beyond the boards described here include three-dimensional molded plastic boards and the increased use of integrated circuit chips. These and other advancements will keep the manufacture of printed circuit boards a dynamic field for many years.

Although most of the PCB companies specializing in PCB reverse engineering focus on the pursuit of profit in the market, the few have begun to establish a position at a higher level and become the leaders in this field which suggest the high potential of PCB reverse engineering. It improves the technical capability of China enterprises and completely breaks the technical barriers. Wonderful PCB will try to put much more effort into the R&D of PCB reverse engineering and offer better PCB products.

Some Fundamental information of Printed Circuit Board (PCB) Board

Nowadays, printed circuit board is widely used in electric & electronic field. This article introduces the fundamental information of PCB in details, including the definition, Gerber file, NC drill file, solder mask, silk screen, as well as the PCB finishing before ordering a PCB. Hope this tutorial can help our customers to improve their PCB knowledge.

The definition of PCB
For standard PCB, it is the combination of bare board and components on it. While for bare board PCB, it is called printed wiring board. We usually call it PWB.

What is Gerber File?
The Gerber format is a file format used by printed circuit board (PCB) industry software to describe the images of a printed circuit board (Signal, ground, power, solder mask, silk screen, and drilling layout plan, etc.). The Gerber format is the de-facto industry standard for printed circuit board image transfer. The Gerber format specification can be freely downloaded.

What is NC drill file?
THE NC DRILL FILE can be opened by Notepad. The NC drill file should have Tooling Size, and X Y info of the holes. An NC drill example is below: T define the hole size, X Y define the hole location. NC drill file can also define the NPTH holes; the best way is to generate a separate NC drill for NPTH holes (Non-plated holes).

Solder mask and silk screen:
The green or white oil on PCB is called solder mask, which is functioned as dielectric protective layer, can protects copper traces and also can prevent components to be soldered at incorrect place. Solder mask comes in different media depending upon the demands of the application. The lowest-cost solder mask is epoxy liquid that is silk screened through the pattern onto the PCB. Other types are the liquid image able solder mask (LPSM) inks and dry film image able solder mask (DFSM). LPSM can be silk screened or sprayed on the PCB, exposed to the pattern and developed to provide openings in the pattern for parts to be soldered to the copper pads. DFSM is vacuum laminated on the PCB then exposed and developed. All three processes go through a thermal cure of some type after the pattern is defined.
On the dielectric 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: www.wonderfulpcb.com Wonderful PCB Technology Co., Ltd is a professional PCB manufacturer for many years and could try best to help!

Printed Circuit Board (PCB) Blanking

According to PCB material, hole and shape processing can adopt the method of mould cutting, to a simple PCB processing or request is not high PCB can be used in a cutting way.Suitable for low level and the requirements of the mass is not very high PCB PCB production and appearance requirements is not very high, the cost is low.

Punch:

Production batch is big, the amount and type of hole and more complicated shape of single-sided paper substrate and non-metallic hole of epoxy glass cloth substrate double-sided, usually USES one or a few pay mold punching.

Appearance:

PCB production batch of the appearance of single panel and double panel, usually USES the mould .According to the size of the PCB, can be divided into the blanking die and whereabouts is expected to die.

The composite processing:

PCB hole and hole, hole and shape between the requirement of high precision, at the same time in order to shorten the manufacturing cycle, increase productivity, the composite mould machining hole and the appearance of the single panel at the same time.

With mold processing, PCB, the key is to mold design, processing, need professional knowledge, in addition to this, the mould installation and debugging is also very important, at present most of the PCB factory molds are made outside the factory processing.

Mould installation considerations:

1. According to the mold design and calculation of blanking force, the size of the mould, such as height choose punch (including type, tonnage).
2. Start the punch press, comprehensive review include the clutch, brake, slider, etc. Each part is normal, whether the operating mechanism and reliable, and should have no impact phenomena.
3. Die under the pad iron, generally is 2 pieces, must on the grinding machine grinding out at the same time, to ensure that the mold installation parallel and vertical.Shim placed leap put namely don't hamper blanking and near the center of the mould, as far as possible, at the same time.
4. To prepare a few sets of platen and T head clamp screw, so that the corresponding use and die.Linking piece without touching lower die straight front wall.The interface between should pad cloth, must tighten the screw.
5. Be very careful when mould installation on the screw, nut don't meet lower die mould (upper die down, closed).
6. Adjust the mould using hand as much as possible, instead of motor.
7. To improve the cutting performance of base material, paper board to be hot.The temperature at 70 ~ 70 ℃.
Die cutting of the PCB hole and shape, its quality defect has the following several:

Around the hole of the bump or copper foil case become warped or layers;Between holes and hole crack;Partial or hole itself is not a vertical hole position;Burr;The section coarse;Coining the PCB into the bottom of the pot shape warping;Waste jumping;Waste blocked.

The check analysis steps are as follows:

Check if the punch blanking force, rigid enough;Mold design is reasonable, whether rigid enough;The convex and concave die and machining precision of the guide pin, guide sleeve, if, if installation concentric, vertical.Fit clearance is uniform.Convex and concave of the gap is too small or too metropolitan produce quality defects, is a mold design, processing, and debugging, using one of the most important question.Don't allow the rounded edge convex and concave die, chamfering .Taper is not permitted in punch, especially when punching both positive cone and cone are not allowed.In production to pay attention to whether convex and concave die blade wear at any time.The discharging mouth is reasonable, small resistance.Pushing plate, a feed rod is reasonable, strength enough.Washed the plate thickness and the substrate binding force, the gel content, and the adhesion strength of the copper foil, to hot humidity and time is also cutting quality defects such as analysis of factors to consider.

Mr. Sam Duan

Mail:wonderful25@wonderfulpcb.com

Something About the Flexible Print Circuit Board(FPCB) You Should To Know

FPCB, all known Flexible Print circuit board or Flex Print circuit Board, it is attached to the flexible substrate on the dry film, exposed, developed, produced on the substrate after etching conduction lines. In terms of its relative rigid printed circuit boards can be curved flexible, smaller and lighter. In electronic products play a role in conducting and bridges make the product better performance, smaller.

Main material: polyimide + adhesive + copper are also non-adhesive backing, which only copper + substrate, its price is higher, less in the current application, unless special needs.

Copper CU (Copper Foil) in the material is divided into rolled copper RA (ROLLED ANNEAL Copper Foil) and electrolytic copper ED (ELECTRO DEPOSITED Copper Foil) two kinds, the characteristics of the mechanical properties of rolled copper is better, there are scratch off most requests are made rolled copper. Thickness is divided into 1/2oz (0.7mil), 1oz, 2oz, three are generally used 1oz.

Substrate in the material is divided into PI (Polyimide) Film and PET (Polyester) Pilm two kinds, PI's price is higher but its better flame resistance, PET lower prices but not heat. So if it needs most are made of welded PI Material thickness is divided into two kinds of 1mil 2mil.

Reinforcing material Stiffener soft board soldered parts or local area in order to increase reinforcement in order to install and another pressing up of hard material reinforced PI and PET film is divided into two kinds of materials as Epoxy FR4 material commonly known as urea resin plate reinforcement materials in general are feeling Caulking RESSURE SENSITIVE ADHESIVE fit with soft board, but you are using PI reinforcement film adhesive (Thermosetting) lamination.

Surface treatment

1. Rust treatment - on the surface of bare copper antioxidants
2. Tin-lead printing - the bare copper surface with solder paste printing another reflow furnace
3. Plating - Plating Tin / lead (Sn / Pb) nickel / gold (Ni / Au)
4. Chemical deposition - chemical solution deposition way to tin / lead nickel / gold surface treatment

Features:

Can be curved flexible, small footprint, light weight, stable transmission characteristics, sealing, insulation, good assembly process

Application areas:

Automation instrumentation, office equipment, communications equipment, automotive instrumentation, aerospace instrument, cameras and other PCB board .

Classification:

(1)According to sub-layers: * Single Layer board * Double layer board * Multilayer board (two or more layers)
(2) By material: * Soft board * Rigid PCB board * Rigid-Flex PCB board

Some Knowledge About PCB Board Panelization

A key to saving money on PCB manufacturing during the design phase is to optimize the usable area available for each standard manufacturing panel.

Some manufacturers suggest that you put a number of different circuits on the same panel to improve material utilization and reduce manufacturing costs. At wonderful PCB Limited, we do this automatically as part of our pooling process, so there is no need for you to waste valuable design time. Of course you can suggest us your idea of panel size.

Penalization will do much help for the assembly process. If your layout uses SMD components we automatically panelized a solder-paste layer which you can download as a Gerber file for stencil manufacture. We can generate the paste files from the SMD pads on a "best-efforts" basis but it is not always clear to us which pads to include and which to leave out. So we recommend that you check these files before you use them. It is much safer to generate a paste file yourself and include it in the data you send us. We will then check it with the rest of the data and step and repeat it into the same assembly panel.

There are several ways to panelization of the PCB boards. Normally by V-cut, stamp hole and routing. No matter what kind of method you want, we can make it for you. And we can offer you the best solution. Manufactur ability rules: (1) Minimum dimension of the single PCB is 5 by 5 mm. (2) Maximum panel dimensions on the Verified and Verified Plus service is 250 x 350 mm.

Here are some of the PCB boards that in Panel for your reference.
First one is by V-cut and routing, the second is by stamp hole.