Steps to a successful PCB assembly for efficient PCB prototyping and production

By | Date posted: | Last updated: September 7, 2024
PCB Assembly

Printed circuit boards (PCBs) are the backbone of all electronic and many electrical devices, providing the essential foundation that enables these devices to operate at the desired standards. Over time, simple PCB designs have evolved into complex and sophisticated printed circuit boards that power an ever-growing range of advanced machines and equipment. As gadgets become increasingly integrated into every aspect of human life, the importance of printed circuit board prototyping becomes more critical than ever. In high-stakes applications, such as healthcare, where gadgets play a pivotal role, the margin for error is non-existent, underscoring the vital significance of PCB prototypes and assembly.

The process of assembling printed circuit boards, commonly referred to as printed circuit board assembly (PCBA), involves soldering electronic components onto a circuit board. It’s important to note that PCB assembly is distinct from PCB manufacturing. The manufacturing of a circuit board typically occurs after the design, prototyping, and testing phases have been completed. However, PCB assembly takes place both during the prototyping phase and after the circuit board has been manufactured. This dual-stage process ensures that the final product meets the required specifications and functions correctly.

There are some items critical for assembling a Printed circuit board, these include

  • Circuit board
  • Electronic components for soldering
  • Soldering equipment
  • Materials such as solder paste and wire
  • Testing equipment

The most important PCB Assembly Process Steps:

  • Drawing up an Assembly Diagram
  • Adding Solder Paste
  • Component placement onto board
  • Board Reflow
  • Inspection
  • Final Assembly
  • Cleaning

Create a PCB assembly design

The first and most important step in printed circuit board assembly as well as manufacturing is the design of the PCB; it is like a pictorial road map that guides you to where each electronic component should be located on the circuit board. Assembling a circuit board is virtually impossible without a PCB assembly diagram; at best you will be able to create a low-quality PCB board prototype that is likely to fail most quality tests and will need considerable remaking to ensure it meets quality and performing standards. Printed circuit board Assembly diagram will accurately capture what components are required for assembling, their arrangement on the circuit board and how they will connect with each other for best performance. Check out the guide on How is Circuit Board Prototyping best option for innovative PCB design.

Applying Solder Paste

The actual process of PCB assembly starts with the application of solder paste to board with the help of stencils that are customized based on final product application. It is important to ensure that the circuit board and the stencil are facing the same direction and that the solder pads on the circuit board are fully aligned to the stencil cutouts. Make sure the stencil stays in place while you apply the solder paste.

Assembling the Components

Component Assembly can be done either by hand or with the help of a machine. The Machine Assembly of the circuit board can be done in two ways,

  • Surface Mount Assembly
  • Through-Hole Assembly

Surface mount assembly is generally used when small components need to be directly placed on the surface of the circuit board. These machines can mount all the components within minutes greatly increasing the speed and efficiency of the prototype PCB Assembly process.

Larger components like LED’s and capacitors on the other hand need to be soldered onto the circuit board using through-Hole Assembly process wherein they are manually placed on the circuit board. It is only after visual inspection has been done to ensure that each component is being placed on the right pad before soldering it in.

Board Reflow

After soldering the components onto the circuit board is completed, they are then passed through the reflow oven to bond the components with the circuit board mechanically. This ensures that the components are firmly connected, electrically and mechanically to the circuit board and to each other.

Inspection post Board Reflow

Post reflow inspection with the help of pinhole cameras helps ensure that the connections between the components are placed at the right locations.

Final Assembly

Final Assembly of printed circuit board is done to place any remaining small components as well as repairing and soldering of any misplaced components or electrical connections.

Cleaning

The last process in PCB assembly involves remaining flux from the finished printed circuit boards. New technologies like the aqueous system have made it possible to remove solder paste and flux from board without using chemicals harmful to the environment.

Conclusion
Prototyping is a vital step in any product development process. PCB prototyping service is particularly crucial, as different applications require various types of PCB assembly. Without assembling a prototype to conduct an actual functionality test, you risk ending up with a suboptimal product. In the past, printed circuit board prototyping was often costly and time-consuming, primarily because the assembly process had to be outsourced. However, advancements in technology have now made it possible to conduct circuit board prototyping on-site, making the entire process significantly faster and more cost-effective. This has streamlined the production of PCB prototyping boards and enhanced the efficiency of the prototyping phase.

Technotronix is an ISO 9001-2015 certified with having RoHS compliance PCBA and PCB prototyping expert. Contact us for custom and quick turnaround PCB assembly services for your electronic product at [email protected] as, we are just a click away on the internet freeway!

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5 Common Mistakes in PCB Assembly that can cause PCB failure

By | Date posted: | Last updated: February 14, 2022
pcb-assembly-process

An integral part of most electronic and electrical devices in play nowadays, Printed Circuit Boards (PCB’s) are essentially consists of layers of copper traces connecting together different components to create a complex maze of circuits. The importance of a PCB can be directly gauged by the fact that any errors in its design or assembly can affect the performance and output of the end product. Irrespective of whether you are fabricating PCB’s for a small electrical company or a global technology giant, there are a large number of complications and challenges that can arise during the PCB assembly process that can severely compromise the quality of the final product. Smooth collaboration is a must as far as PCB assembly is concerned, all stakeholders, including designers, engineers, manufacturers and fabricators need to work together to ensure the assembly process runs smoothly and is free of errors. A faulty PCB assembly can end up costing the organization dearly in terms of loss of reputation and returned delivery.

The potential for mistakes during the PCB assembly process exists during any of the process steps, it could be the result of flaws in the technical design itself or it could be the product of operational errors. While there can be any number or reasons for errors in the PCB assembly process, below are 5 of the most common errors mostly responsible for PCB failures.

Reasons for PCB Failure:

Cracking of Flex

Flex cracking is a term used when the excess stress on a ceramic chip capacitor causes the PCB to bend excessively when passed through it. Ceramic chip capacitors are designed to withstand a specific load, when the load generated by a PCB exceeds its maximum capacity, it causes stress on the ceramic chip capacitor which in turn causes the PCB to bend. It is important to use the same or similar load level ceramic chip capacitor during assembly as used during the design phase to ensure the capacitor does not come under stress and cause the PCB to bend or crack leading eventually to PCB performance failure.

Non-marked polarities

Assembling a PCB requires many different components like batteries and diodes which are characterized by polarities. Marking out the polarity of each individual component is very essential to make it easy for assembly engineers to differentiate between anodes and cathodes. In case the polarities are not marked clearly or are wrongly marked, there is very high likelihood of the wrong polarity getting connected to the wrong terminal during the PCB assembly process. Short circuits in PCB are very often caused by wrong connection between polarity and terminal and might even lead the circuit to blow up or at the very least cause some components on the PCB to be completely destroyed.

Inadequate Copper-to-Edge Clearance

Coppers high conductive properties make it an ideal metal for use in electrical and electronic PCB’s. However, as a metal, copper is also highly susceptible to corrosion which can happen if the copper layers get exposed to the environment. This is why copper used in PCB assembly is often coated with other materials like plastic to prevent corrosion. But sometimes during the process of trimming the printed circuit board, the copper coating also gets trimmed, causing the layers beneath to get exposed to the environment increasing the probability of corrosion and malfunctioning of the PCB. This mistake can easily be avoided by ensuring that the space between the edge of the board and the edge of the copper, also known as inner clearance or copper to edge clearance follows specific quality standards.

Plating gaps or voids

An important part of the PCB assembly process is the electroplating deposition process. This process is used to drill holes through the circuit board through which electricity can be carried from one end of the circuit board to the other. Once the holes are drilled, a thin electroless copper layer is added to the board and along the hole walls, which acts as a base for subsequent layers to be added for etching a printed circuit board. Errors during the deposition process can cause holes in copper plating which can prevent the passage of electricity through the hole causing the entire PCB to fail.

Component Misalignment

Each component on a printed circuit board has a specific landing place. Sometimes components shift from their target location during the soldering process by attaching themselves to the molten solder. A misaligned component can disrupt the proper flow of electricity through the circuit board causing the entire PCB to fail. There are only instances when an entire component gets missed during the assembly process leading to system malfunction.

Conclusion
PCB assembly requires skill and expertise, but even then there is scope for error unless you have put adequate quality controls in place at every stage of the PCB assembly process to ensure that one small error in assembly does not cause the entire product to malfunction.

TechnoTronix is one of the kingpins in delivering a well-defined and proven PCB layout and PCB assembly service to the electronics manufacturers. Our main strength lies in the extensive experience and skilled team of experts to provide error less and lead-free PCB assembly and manufacturing solution. You can drop an email to [email protected] or give us a call at 714/630-9200 to solve your queries or to get a quote.

What is the Need of Chemical-Free PCB Fabrication & PCB Assembly?

By | Date posted: | Last updated: February 14, 2022
pcb-assembly-1

Commonly referred to as PCBA, printed circuit board assembly refers to the process of rigidly mounting electronic components onto a printed circuit board. It is essentially a mechanical assembly process of soldering or assembling disparate electronic components onto one printed circuit board in a manner that enables packaging. A fully functioning PCB is by no means a finished product; it needs to be connected to a power source as well as a display monitor for displaying information. PCB assembly is not generic; they are assembled as per detailed specifications related to the placement of connectors, mounting boards, etc. In many specifications the specifications are detailed enough to require a drawing of the exact location and dimensions of each external component, for instance specifications related to height or keep out areas need to be defined and designed before the fabrication and assembly process itself.

It is common to confuse PCB assembly with PCB manufacturing; the two are completely different and distinctive from each other. Manufacturing PCB’s requires Making and prototyping before actual production while assembly requires soldering of electronic components onto the circuit board for use in a variety of gadgets and equipment. There are many materials required in PCB fabrication and assembly, the primary ones being:

  • Printed Circuit Board
  • Electronic components
  • Soldering materials, including solder wire, solder paste, solder bar, solder preforms (depending on the type of soldering to be done)
  • Soldering flux
  • Soldering equipments including soldering station, wave soldering machine, SMT equipment, inspection and testing equipment etc.

By the late 1900’s, the threat to the earth’s ozone layer posed by emissions from CFC based defluxing solvents like Freon and Trichloroethylene brought about a renewed focus on the need to reduce the use of chemicals in manufacturing. The increased clamoring led many organizations to abandon CFC based defluxing solvent sin favor of aqueous based defluxing as well as no clean fluxes. The standards of defining green technology have evolved considerably since then, also because of regulatory directives which have made it imperative for companies to adopt cleaner chemical free PCB fabrication and assembly. Organizations are increasingly looking to adopt methods that reduce product liability as well as environmental liability as a means of bringing down their carbon footprints.

Taking care of the environment

Environmental concerns aside, safety in the workplace also becomes paramount not only during process operations, but also with regards to performing routine cleaning and maintenance functions, which are why many environmentally committed organizations have started adopting lead free soldering, even though it sells at a 200-300% premium. It is not just workers in factories where PCB assembly takes place that are susceptible to exposure from toxins released during the process, but even the end consumer purchasing these products.

Environment friendly PCB cleaning processes

It is in the cleaning process of PCB assembly that chemicals are chiefly used, although there are many industries that require use a no-clean process. However, industries like aeronautics, automotive and medical industry do require post assembly cleaning of solder reside paste. It is these industries that have demanded that manufacturers of PCB fabricators and assembly adhere to chemically reliable cleaning solutions that are also environmentally friendly. The European Union already has strict guidelines regarding chemical free fabrication and assembly of PCB’s. The ROHS directive is very clear in its stipulations that, from July 2006 onwards, member states are required to ensure that new electrical and electronic equipment released in the market should be free of lead, mercury, cadmium, hexavalent chromium, PBB or PDBE. Since the ROHS Circuit Board guidelines are a product based initiative, the responsibility for compliance lies with the manufacturer. This means that from an environmental perspective, flux and solders paste residues commonly used for high reliability and long lifecycle PCB assembly products need to be compatible with solvents and detergents required to clean them.

The normal environment that we live in is already rich in pollutants which are why it has become even more imperative to ensure that we do not add to the contamination by adopting manufacturing and assembly processes that do away with using any kind of harmful chemicals. While there is no regulatory body in the US for testing of PCB Fabrication and Assembly processes, the government has come out with initiatives that make it mandatory for organizations to use non lead based products in their fabrication and assembly process. Apart from the government based initiatives there is an increasingly active role played by nongovernmental environmental agencies to raise awareness about the safety hazards posed to workers and consumers by the use of chemicals in PCB fabrication and assembly without sacrificing on quality or reliability. Even organizations now prefer working with PCB assembly suppliers who are committed to implementing advanced processes and using high quality raw materials that reduce environmental contamination and provide an increased level of health and safety to workers and consumers.

TechnoTronix is one of the kingpins in delivering a Chemical-Free PCB Fabrication & PCB Assembly service to the electronics manufacturers. Our main strength lies in the extensive experience and skilled team of experts to provide tailored electronic design and manufacturing solution. You can drop an email to [email protected] or give us a call at 714/630-9200 to solve your queries or to get a quote.

How pcb layout and PCB assembly is setting a new trend of electric vehicle charging stations

By | Date posted: | Last updated: April 9, 2021
PCB Design

With the Electric vehicles (EV) becoming a recent buzz in the UK, new modifications in the vehicle charging stations come up every other day to reap the advantages of the saving fuel. People are also staying conscious about the environmental protection and using Eco friendly products and gadgets as much as possible. To derive innovations in car charging stations, an exact pcb layout and PCB manufacturing solution is the key success factor. This article drives you to the basics of vehicle charging station and the printed circuit board used in its manufacturing and installation. It also outlines the current modifications seen on charging stations.

As more and more people choose to opt for a plug-in hybrid vehicle or an electric car, it is vital to first get a short brief about the PEV’s. The battery electric vehicles operate through the an electric motor. While the plug in hybrid electric vehicles has both, an electric motor and gasoline engine. The PEV’s need to be charged on a regular basis to get high efficiency in the average miles. This has made the researchers forecast the increased use of PEV’s will drop down the number of conventional fuel stations than that of electric car charging station with making the electricity to be a propulsive dominance for vehicles, especially in the UK. The issue of car charging station is heading the electronic industry to come up with far reaching unique solutions.

With this, the tipping point for the modified charging station is grounded on the PCB Assembly manufacturing to come up with an improved electric design and manufacturing solution. In order to increase the potential of EV’s, the issues pertaining to the lack of charging station in every zone be it a free vehicle recharge or a ‘pay to charge’ option becomes a prime concern.

Giving a dynamic arena to the PEV’s, many charging stations are now installed in the UK, but still there is many more developments to be made with up-gradation of technology. The high tech PCB prototypes to design and manufacture the charging stations, be it charging point for homes, commercial or public use is taking a next step in enhancement that has multi functionality features. Also modifications are addressed in getting customized solution for wall mounted type of charging station or a pedestal structure or a ball top/curve top style of the charging station.

To manufacture an entry level commercial charging unit or robust vandal resistance EV charger that has a versatility in 1 way or 2 way plug in with custom fast charging versions or to discover a heavy vehicle charging station needs an effective electronic and design solution. With the help of flexible PCB, technology has made it possible to come up with security innovations that includes c/w hatch lock and overload protection with fault current security. For the manufacturer of charging stations, it proves challenging to also have well defined charging test equipments.

A device that has automatic charging capabilities with auto plug-in and payment facilities is a challenge to the electronic manufacturers. The use of an embedded controller in the system gives NFC and internet capabilities for mobile payment. The major challenge here is on the electronic manufacturers to reduce the cost of production with high efficiency grounded on the systems installed in the charging station.

The EV control center is also high in trend that offer both the options- pay to use Or free to use car charging service. With a single control panel it manages the multiple local EV charging points. The driver has to simply park the car in EV charging point which automatically initiates the charging procedure.

The customized PCB assembly with state-of-the-art techniques of production like the Surface Mount Technique (SMT), Through-Hole Technique and many others are highly in use to get a compact and multi feature printed circuit board used in automobile industry. To get a complete turnkey PCB Assembly for the high-tech control system used in EV’s, it requires an effective PCB assembly and also a consultation of a PCB expert.

Technotronix provides a tailored electronic and layout solution for the manufacturer and designer of vehicle charging stations. Having an experienced team of technical experts, we provide customization in PCB assembly and derive a tech savvy pcb layout for your project by providing a consigned and complete turnkey solution. Our main strength lies in the extensive experience and offering quality electronic design and manufacturing solution. You can drop an email to [email protected] or give us a call at 714/630-9200 to solve your queries or to get a quote. To get more insights into the PCB assembly, Check out our PCB Assembly Services!!