Which Matters Need Attention of the Manual Welding?

Surface-mount manual soldering is sometimes more challenging than through-hole soldering because of smaller pin spacing and higher pin counts. In the rework process, we must be careful not to overheat the printed circuit board, or plated through holes and pads are easy to damage. Manual soldering and rework are process steps that require outstanding operator technology and good tools. When equipped with adequate tools and training, the operator should be able to create reliable welding points. So in the PCB assembly and PCB manufacturing process of manual welding process should we pay attention to?

1.Pay Attention to the Protection Against EOS Damage

Electronic components and PCBA are susceptible to accidental electrical energy from many different sources. Therefore, the operating table and tools should be grounded and have a sound anti-static measures.

2.Safe Voltage and Safe Current

In the course of operation of soldering iron and tin, you should pay attention to electrical safety, to prevent the electrical shock for your body.

3.Civilized Operation

• The power supply should be switched off when did not welding. The correct placement of iron and other tools，to prevent burns
• In the welding process, you should be careful not to throw away the paste solder. After welding you should remove the wire head, tin slag and other surplus material;
• Welding process should prevent the connecting finger get solder or other contaminants, to prevent connecting finger injury.

The above is the manual welding precautions, in order to better complete the welding, we should strictly abide by the rules to ensure the welding quality.

How to Select and Evaluate the Solder Paste?

Solder paste is a homogeneous mixture consisting of a mixture of solder and gold metal powder, paste flux, and some additives, with a certain viscosity and good thixotropic paste. At room temperature, the solder paste can paste the electronic components in a given location, when heated to a certain temperature it can make components and pads connected together to form a permanent connection solder joints. How to choose a suitable solder paste? It is a quality assurance in PCB assembly and PCB manufacturing.

The Problem of Choosing Solder Paste You should Pay Attention To

1, the Consistency of Solder Paste Batch

When selecting solder paste, it is best to ensure that the supplier has the ability to ensure the consistency of the quality of each batch of solder paste and the adequacy of process control and inspection procedures to ensure consistent solder paste quality.

2, Reliability

The final selected solder paste must have long-term reliability on the PCB and must comply with the SIR and electromigration of GR-78 requirements.

How to Evaluate Solder Paste

1, the Flow Characteristics of the Solder Paste

The chemical reaction between the solder paste flux and the solder alloy affects the flow characteristics of the solder paste, and rheology is critical to the solder paste printing performance.

2, the Stencils Life of Solder Paste

Any solder paste has to be printed well on the stencil, and the same paste has a good printability after several hours on the stencil.

3, Solder Paste Adhesion

As the different of lead-free solder paste and lead solder paste formulations are vary widely, it is necessary to determine whether the lead-free solder paste has good adhesion and the ability to maintain component placement stability.

What are the Requirements of PCB Tray in SMT Production?

In the processing process of PCB board, in order to protect the PCB board from electrostatic hazards, will use the PCB tray or PCB card board to place. PCB tray full name of anti-static tray, the main role is to reduce the PCB board damage in the process of transport, avoiding collisions and reducing the rate of damage. The groove design in the tray is to save space and also enhances the tightness between the trays. Greatly reduce the incidence of defective products, improve work efficiency and improve the production process.

The Requirements of PCB Tray in SMT Production

• PCB tray, anti-static components rack, turnover box, truck, etc. every six months for an anti-static performance check;
• PCB tray and antistatic containers used by workers should be cleaned regularly. Anti-static table mats, tools and containers should be cleaned with neutral cleaning solution every month.

When we purchasing the PCB tray must choose the right one and have to ensure the quality of the PCB, the PCB tray of the production materials must meet the following characteristics:

• Highly dimensional stability
• Good thermal shock resistance
• Keeps flat even after repeated use
• Corrosion resistance (flux and cleaning agent)
• No moisture absorption

In the PCB manufacturing and PCB assembly process, not only to use anti-static tray to ensure the quality of production, but also should do a good job of anti-static protection in the production workshop, operating personnel wear static wrist, wear static clothes and static shoes can play Electrostatic protection for PCB production.

The US Block China's Semiconductor Industry Development -- Opportunities or Blow

The US President Barack Obama recently released a new study, made recommendations to strengthen the protection of the US semiconductor industry, limiting foreign investment, acquisition and merger of the domestic semiconductor industry. The news has been issued, Chinese semiconductor manufacturers are beginning to restless. China is keen to acquire foreign well-known semiconductor brands, in order to obtain its internal core technology, eliminating a lot of capital costs. Semiconductor is widely used in the PCB assembly and PCB manufacturing, why the United States to take this measure?

But in fact, the United States to take this tough protection measures to protect their own investment, acquisition and trading market is really an obstacle for our development? It is really bad for China's semiconductor industry? In actual fact, in the other hand, this may promote China's progress in the semiconductor industry.

Currently the world's semiconductor industry development go hand in hand, the world's mainstream processor architecture is X86, ARM, in addition have MIPS, power and so on. The owners of X86 and power architecture are Intel and IBM. They are all US companies, ARM has been acquired by Japan's Softbank, MIPS for the British company Imagination owned. But China HUAWEI Hass developed the ARM architecture server chips may help China tear the monopoly server market of Intel, enhance China's server chip market strength.

Moreover, China has established the IC Industry Foundation has been successful in promoting the development of China's chip industry, China for the production of electronic products required for a great chip, the number accounted for more than half of the world, if the United States hinder the development of China's semiconductor industry, Is bound to force China to strengthen the development of their own chips, do not have to rely on others, self-sufficiency.

So, for many people think that the United States to block the development of China's semiconductor industry is a blow to China, I do not think so, this will be a opportunity to test China's own strength，for China's semiconductor industry will be a qualitative leap.

The Significance and Advantages of AOI inspection Equipment in SMT Production

In the SMT production, the equipment of the different parts to play a different role, the automatic optical inspection device is scanned optically by the CCD camera to read the image of the device and the solder foot, It is a device that detects defects in solder paste, solder joints, and electronic components on PCBA boards by logic algorithms or image comparison methods to determine deviations, lack of equipment, short circuits, and so on.

The Significance of AOI inspection Equipment in SMT Production

We have the subjective nature in the manual inspection process that resulting in the results of bias. Therefore, we will introduce AOI equipment for a comprehensive PCBA board inspection in the process of electronic production, but also improve the production efficiency and through rate. Especially for high-density complex surface-mount PCB, rely on manual visual inspection, neither reliable nor economic.

At the same time, with the SMT technology used in the PCB circuit pattern refinement, SMC / SMD components of miniaturization, high density and rapid development of SMA assembly, decided we must use AOI equipment.

AOI inspection equipment has the following advantages:

1, to solve the structural examination problems of micro-packaged devices to ensure the quality of production;

2, improve the back-end test through rate, lower maintenance costs;

3, with the development of technology, AOI test program quickly and easily, reducing the production of a large number of test costs;

Modern electronic processing plants are developing in the direction of science. Enterprises need to continue to introduce all kinds of equipment in line with their own development, improve production efficiency and save production costs. Only progressive enterprises can survive in a competitive environment.

How to Buy BGA Rework Station?

With the BGA chip in the electronic processing of a wide range of applications, including computer motherboards, mobile phones, web cameras, TV motherboards, communications products and other fields, there will be damaged in processing,BGA rework station role is also growing. So in the PCB manufacturing and PCB assembly process, how should choose a suitable BGA rework station? We list out useful experiences:

1, according to the characteristics of their products to determine the size of the purchase of repair equipment range

Depending on the size of the PCBA board to be serviced frequently, determine the size of the BGA rework station which we should be purchased. At the same time, BGA Rework Station should be equipped with a flexible bracket, So that in the course of work, can make the positioning and fixed on the Rework Station quickly and conveniently. Finally, select the range of tip sizes according to the maximum and minimum values of our frequently serviced chips.

2, you expect the functional requirements of BGA rework workbench

Depending on the complexity of the product, the operating temperature range of the device is determined. The three temperature zone is the minimum ground requires, complex PCBA board should buy four zone of temperature. At the same time, BGA rework station should also be equipped with upper and lower temperature zone and infrared preheating area, upper and lower supplementary heating can better guarantee the heat required for welding, but also can eliminate the local heating caused by excessive PCB distortion. At the same time, BGA rework station should also be compatible with BGA, CSP, LGA, QFP, PLCC and other chip rework.

These are the two most important purchase criterias, Of course, the other plus welding, cooling, intelligent temperature curve settings and temperature control accuracy, etc., are secondary. You can choose according to your own requirements, I believe you can choose a suitable BGA rework station.