How does the solder paste play a significant role in PCB SMT Assembly?

By | Date posted: | Last updated: September 20, 2021

Solder Paste is an important component that assists in holding electronic components in place on the PCB board.

Solder Paste is used to create electrical connections and mechanical bonds between printed circuit board pads and surface mount devices.

Typically it is made up of powdered solder in a flux paste. The flux has several important roles to play. These include:

  • Removing oxidation from metallic surfaces.
  • Protects components that are to be soldered.
  • Acts as a temporary low-tac adhesive to hold devices in place till the reflow process is undertaken.

There are a number of factors that affect the performance of solder paste. These include:

  • Uniformity and Size of Particles in Solder Paste.
  • Percentage of solder powder in the flux.
  • Viscosity of the Solder Paste.
  • Thixotropic Index and Metal Content of Solder Paste.
  • Reflow Process.

A wide majority of PCB circuit board failures occur on account of issues related to the solder paste process. Hence extreme caution is required when it comes to its application. Particularly as electronic devices get smaller, precision placement becomes increasingly critical. While high-speed pick and place equipment can accurately place components, if the soldering process isn’t carefully done, it affects the efficacy of the final device. A solder paste that is too thick or that is not applied right will lead to a poor connection. Solder paste applied in excess can also result in bridge shots, while if it is too light it will lead to inferior connections.

Classification of solder paste

Based on its flux type, solder can be classified into 3 broad types as below:

Rosin based solder pastes

This paste is made from a natural extract from pine trees. It is possible to clean these fluxes after the soldering process with the help of a solvent.

No clean solder pastes

Made of resins and solid residues, these pastes are preferred on account of the fact that they are low on the following:

  • Cleaning costs
  • Capital expenditure
  • Floor space

However, such pastes need an extremely clean assembly environment.

Water soluble flux solder pastes

They are made up of organic materials and gycol bases and have a number of cleaning agents.

Properties of solder paste

Some of the important properties of solder pastes include:

Viscosity – Simply put, it is the tendency to flow. If the metal content increases, the viscosity goes up. Similarly, viscosity has a strong correlation with temperature.

Slump – Slump refers to the spreading of the material after application. Slump largely depends upon:

  • Temperature
  • Height of paste deposited

Rheology- Rheology determines the flow of solder paste under certain conditions. Rheology also impacts the print quality of the paste.

Applications of Solder Paste in PCB SMT Assembly:

Solder paste finds extensive application in the following processes:

  • Reflow soldering process – Solder paste is used for reflow soldering when it comes to PCB SMT assembly.
  • Creating solder joints – As a homogenous mixture of solder alloy and flux, solder pastes help create reliable solder joints.
  • Lead components – They are useful in assemblies with leaded components as they lower the cost of PCB fabrication and help in high component density.
  • Stencil Printing – Useful in stencil printing, it helps to stick to the given pattern of component addition on the PCB.
  • Jet Printing – Jet printing solder paste is made from a different formula, so the paste is more liquid. Jet printing provides PCB assemblers with a great amount of flexibility & the ability to control the amount of solder being applied.

Areas to be mindful of, in the use of solder paste

There are a number of aspects to take into account to ensure that there are no errors in the application of solder paste. These include:

  • Ensuring the stencil is accurate – For reliable results, what is needed is accurate PCB SMT stencils. Poorly printed stencils can impede application of the solder paste.
  • Ensuring the screen printer is programmed correctly – Accurate measurement & calibration of solder paste screen printing devices is key.
  • The right amount of solder paste – The amount of solder paste needs to be accurate as both an excess and lack of it can cause errors
  • The right process – You can choose between metal screen printing and mesh screen printing. While mesh screen printing is more economical, it isn’t suited for small surface mount devices.

To sum up

Solder pastes inspection and its application are the key steps in PCB operations as they can reduce defects. An accurately applied high-quality solder paste will ensure that the board and the final device work accurately.

At Technotronix, we are fully equipped to handle your PCB manufacturing requirements. We have over 40 years of experience in SMT PCB assembly. Our team of experts and state-of-the-art manufacturing facilities ensure that all our PCBs meet industrial standards. If you are looking for high-quality SMT PCB solutions, you can submit your requirements via PCB SMT assembly quote form.

How to find the Perfect Electronic Assembly Company for your Industry?

By | Date posted: | Last updated: July 29, 2021
Electronic Assembly Company

The choice of the right electronics assembly company is one of the most crucial decisions that you can take when it comes to the success or failure of your electronic product. Taking the time to get a comprehensive understanding of the company and its competencies can go a long way in saving you precious time later.

Here is a handy guide on the factors to look for in making your choice:

Experience of the Electronic Assembly Company

With miniaturization of devices, PCBs are becoming increasingly complex. To this end, you need a manufacturer who has the requisite experience. Such manufacturers will be armed with a huge body of industry best practices that will ensure that you do not have to reinvent the wheel. Some of the areas to probe include:

  • How many years have they spent in the business?
  • What kind of expertise do their professionals have?
  • Whether the manufacturer has experience with surface-mount technology or with through-hole manufacturing or both.
  • What kind of products have they handled in the past? Which industries have they dealt with?
  • What kind of production volumes can they deal with?

Electronic Assembly Quality

You certainly want a manufacturer who gave give you high quality PCB assembly. To evaluate this, involves checking for a number of factors:

  • Does the company have state-of-the-art equipment?
  • Do they have industry leading certifications?
  • What kind of client testimonials do they have? You could even reach out to their clients to evaluate how satisfied they are.

Testing Protocols for Electronic Assembly

Robust testing protocols are what stands between you and a quality product. You need to therefore ascertain the kind of testing procedures the company follows. Automated Optical Inspections, component level checks and in-circuit verification are some of the things to look for. In the absence of these you could contend with costly errors that could even lead to product recalls and cost the company its reputation.

Customer Support at Electronic Assembly Company

Prompt customer support is not just a nice to have feature when it comes to a crucial component like a PCB. You certainly want a manufacturer that can answer your questions and offer proactive solutions. Speaking to the customer support representative and finding out what kind of turnaround times they offer, whether they can customize solutions for you, are all good indicators.

Electronic Assembly Cost

Last but definitely not the least, you want to go with a manufacturer that offers optimal costs. It is important, however, to remember that costs are a function of a number of factors including but not limited to:

  • The quantity required
  • The complexity of the product
  • Shipping costs, and more

Costs however cannot be the sole determinant of your decision as you do not want to chase low costs alone at the expense of quality.

Besides delving into each of the above factors in detail, it will be good to watch out for the following red flags. If you do see them appear, it is a good enough indicator of the fact that the manufacturer may not be the right fit for you:

  • Delay in responding. If you see that your queries aren’t being promptly and suitably addressed, you sure want to give the company a miss. After all, you do not want to be in a situation where you need to follow up on your project without receiving any satisfactory answers.
  • Inability to understand your bespoke requirements. If the manufacturer does not show flexibility in going all out and understanding your bespoke requirements to be able to deliver customized products, this is yet another red flag.
  • Inability to provide references. Now this means that the company isn’t confident of its capabilities and of its clients to express their satisfaction in their services. A definite no-no.
  • Prohibitive costs. If the quote received from the manufacturer is prohibitively high and there are no explanations to go with it, you may want to re think your decision.

Go ahead and choose the right PCB Assembly partner that can do justice to your project and become a partner in the competitive advantage you bring to the table. Get the best PCB Industrial Solutions from us.

Looking for an electronic assembly company? At Technotronix, we have over 40 years of experience in fabricating and assembling high quality PCBs. You can count on us for high quality PCBs, no matter what the level of complexity. With the demand for consumer electronics growing exponentially, what is also growing is the demand for quality electronics PCB assembly. Well designed and assembled electronics circuit boards are the mainstay of the consumer electronics industry.

Request a quick quote for Electronics PCB Assembly

How can SMT (Surface Mount) Assembly Process help to reduce manufacturing cost?

By | Date posted: | Last updated: July 15, 2021
SMT Assembly Process

Surface Mount Technology is essentially a constituent assembly technology that works by attaching and linking components on the board surface through solder-reflow procedures. It offers a number of benefits including the fact that it lends itself to miniaturization as it allows components to be placed in a relatively small space. SMT also is a great enabler when it comes to automated PCB assembly.

Cost-Effective technique

One area where SMT scores significantly is on the aspect of cost saving. While there is an initial expenditure in terms of machinery cost, the positive side is that the machines go a long way in minimizing the manual procedures. This results in a dual benefit. The first that the long-term labor cost is reduced. Importantly, it goes a long way in improving production efficiency, which in turn, lowers cost. With surface mount assemblers using a software to digitally assemble the board prior to actual production, possible errors are minimized. It also has a positive impact in terms of minimizing delays that can prove to be costly.

Here is a detailed analysis of the entire SMT Assembly process that will enable you to understand the cost reduction possibilities at various stages.

The broad stages involved in the SMT assembly process include:

  • Solder Paste Printing
  • Solder Paste Inspection
  • Chip Mounting
  • Visual inspection
  • Reflow soldering
  • AOI
  • X-Ray Inspection
  • ICT
  • Functional testing
  • Depanelization

Solder Paste Printing

This process involves placing an accurate amount of solder paste onto the pad on which the components are to be soldered. For this it is not only important that the solder paste is applied well but also that it is stored correctly at low temperature and brought to room temperature prior to application. In addition, due attention needs to be paid to the scraping angle and speed.

Solder Paste Inspection

This step goes a long way in reducing costs as it helps detect SMT Soldering Defects early. What it enables you to do is to prevent costly defects in the later stages of manufacturing.

Chip Mounting

An essential component of the SMT assembly process, this is completed by way of chip mounters. While small components are placed by way of high-speed chip mounters, the larger components require multi-function chip mounters that run at a low speed.

Visual Inspection

The process of visual inspection once again ensures that any defects can be identified early. Some of the errors that can be identifies at this stage include any missing parts or lack of proper placement. Post the reflow soldering it will be very hard to deal with these defects. Once again, this stage of SMT assembly allows scope for keeping costs in check as if this stage isn’t carried out, you can expect that to rectify the errors later, the production cost will rise.

Reflow Soldering

This process involves melting the solder paste to be able to connect the components to the board. It is the temperature profile setting that determines the reflow soldering capability as also reducing the production costs. A professional assembler can go a long way in keeping the costs in check.

Automated Optical Inspection

At this stage the performance of solder joints is thoroughly inspected. Some of the errors that can be detected at this stage, include:

  • Tombstone
  • Edge On
  • Missing Components
  • Misplacement
  • Bridging
  • Empty solder, and more

Automated X-ray Inspection

Once again, X-ray inspection is a great way to ensure high efficiency of the product and to not having to contend with product defects once the product is sent out into the market.

ICT or Function Test

This test checks for opens and shorts and exposes any defects of components by measuring aspects such as:

  • Resistance
  • Capacitance
  • Inductance

Function tests also go on to test the functions of the assembled PCB to ensure that the final product is extremely reliable.

Over all, therefore, the SMT process has a number of in-built checks to avoid costly errors. These measures drive the final products to display high reliability and integrity. Little surprise then that Surface mount technology for PCB assembly is generally considered to be the lowest cost and minimum hassle process when it comes to new designs.

At Technotronix, we are highly cognizant of the above guide. We have over 40 years of experience in SMT PCB Assembly. With automated SMT Assembly process our boards ensure optimal performance in the most challenging applications. If you are looking for progressive SMT PCBs solutions, you are at the right place. To know more, please explore our PCB Assembly Services!

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Top innovative strategies for automotive PCB assembly

By | Date posted: | Last updated: June 25, 2021
Automotive PCB assembly

From a mechanic to the aerospace sector, the application of the print circuit board has grown for years. Currently developing, so is the need for material progress and ability. Before smartphones and internet madness, PCBs have been widely used – from toys to combat jets. There is a time when a pocket calculator is considered high technology. When people depend on technology, newer innovations continue to be introduced. Electronics Manufacturing Industry have become more assertive, compact, and moving. Accustomed people are connected. The progress that provides more excellent connectivity is also needed to be packaged into each PCB.

Top Automotive PCB Assembly Strategies

For automotive PCB assembly, it requires selecting appropriate materials and a specific design that fulfills the requirements proposed by applicable standards and the ability not to experience problems during production. Therefore, it is recommended to follow several basic strategies as mentioned below.

Component placement and orientation

Placement components and orientation play a fundamental role in determining the board manufacturing’s performance, reliability, and capabilities. When the wave solder is used, the component must be oriented to the direction parallel to the wave direction to prevent bridging soldering or open circuits.

Routing of the signal

Components that absorb more than 10mW or do more than 10mA must require appropriate thermal management and power management components. Power and Ground Planes must be placed on the internal layer. It is better if symmetrical and central elements prevent the bending board. Sensitive signals (such as hours) must be protected from noise sources by plane and controlled impedance. Connections between layers that do high currents must be made using two to four Vias per layer; The use of several Vias allows, in reality, to improve reliability, reduce resistive and inductive losses and increase thermal conductivity.

Sequence and Unique components

More fantastic components (usually most important) are placed first, followed by more minor parts. In addition, analog or mixed components must be placed in a particular PCB area, separating it from the digital member. Significant details are also important: high components (such as electrolyte capacitors) will not be placed next to shorter because this avoids a solder connection that is not severely connected. Applicable rules are maintaining a viewpoint above 45 degrees because this helps manual solder joints inspection.

Thermal Management

The first step consists of identifying components that disappear the most considerable amount of heat, look for the thermal resistance ratings reported in the datasheet. Heat is transferred from members to copper layers, and, as a result, ideal thermal management occurs when the entire board is at the same temperature. Trace thickness, number of layers, thermal path continuity, and the board’s surface are all factors that affect the climate of the operating components.

Thermal vias have the same job as the copper fields. Both are inclined to increase the conductive nature. Using several soil fields and power connected directly to heat sources through thermal Vias, the operating temperature can be reduced dramatically. If several components produce a high amount of heat, it is better to distribute it evenly on the board, thus avoiding hot spots. If, on the other hand, the heat generator is concentrated in several components, it is better to place it in the middle of the board so that that heat is dispersed uniformly in all directions.

Apply DRC rules

Check design regulations must identify problems or errors that cannot match general manufacturing requirements, high-speed electrical requirements, or other requirements for your particular application. It is strongly recommended to run DRC throughout the design process, not only in the end so that it identifies potential design problems early and fix them quickly.

Modern application in the automotive industry

Technology has fully grown into all parts of our lives – including our car. Demands for safety, comfort, and connectivity require a circuit board design to maintain speed – if it doesn’t remain one step ahead. Progress in the automotive industry means PCB applications must accommodate this complex system.

Industrial Truck & Shipping

From various surveys, we can state that as many as 38% of the commercial truck operating costs place humans in the driver’s seat. Price of each thing is increasing at a rapid pace. Thus, people are looking for great alternative with the same benefits. Similarly, the truck sectors are looking forward to such techniques in the field of technology and modern business.

Personal car

While the truck industry may see autonomous vehicles to save costs, the consumer market focuses on other purposes. At present, private cars offer extraordinary technology capabilities made possible by the print circuit board system. However, it is a potential benefit of safety that makes the appointment of car driving so interesting. This is not a problem if but when we will see the vehicle going alone.

Powertrain element

Automatic vehicles need advanced formulas to make them work. The machines seek for specific modifications in the monitoring feature with a view to rationalize the PCB design.

Comfort and Technology Features

It is straightforward to expect those automotive features such as smart locks and navigation systems need computers. The less clear – including many automatic sensors and braking systems – also spiced throughout modern cars.

Advanced Driver Help System

The fennel system is an electronic safety measure that provides sophisticated protection. The system protection system comes with modern amenities like the camera and light features, which improve the changes to avoid accidents.

The Era of the random vehicle advancement

Autonomous drones navigate highways and set goals – while managing to avoid plowing anything along the way. We will soon see driverless cars on road.

The automobile has grown into a collection of complex systems and software – even with humans in control. With ambitions to have a vehicle take over driving, too, the brain of this decision-making vehicle must have the highest quality. Now at the electric charging station in the future, it will charge your car’s cost like a smartphone, and you will then drive your car more “energy efficiently” and more environmentally friendly. Therefore, the EMS, PCB assembly providers are an integral part of the automotive industry.

TechnoTronix is an ISO 9001-2015 certified with having 4 decades of experience in providing PCB industrial solution. We have state-of-the-art equipment and an experienced team that can deliver quality PCB assembly and prototypes that do justice to the ever growing and dynamic demands of automotive industry.