Why Surface Mount Technology is Better Than Conventional Technique

mwcms on September 28, 2022

The standard practice for manufacturing PCBs involved through-hole circuits. It’s a simple method and refers to cutting holes in the circuit board to fit electrical components as required. However, it can be very time-consuming if used for mass production of through-hole PCBs.

Machines drill holes in the boards, mount components over those holes from one side, and then thread the holes in the board using lead. Since innovation leaves no technology untouched, the through-hole practice became obsolete only a few years after surface-mount technology or SMT took the stage.

Surface-Mount vs. Conventional Technique: Benefits of SMT 

It was the solution manufacturers wanted. SMT enables manufacturers to produce PCBs at high speed and with more material efficiency. Furthermore, it brings adequate vibration resistance and the possibility for customized soldering techniques. Let’s take a broad look at how SMT transformed the world of electronics and PCB production practices.

  • PCB Miniaturization

The electrical components attached to circuit boards using the surface-mount technology are much smaller than through-hole interpolation components. The geometric volume and size differences in conventional and SMT techniques take PCB miniaturization to the next level.

The SMT technique has reduced the size of many electrical components by 60% to 70%. Over that, some components even got reduced to 90% of their size thanks to surface-mount technology. The same goes for the weight. Hence, with SMT, PCBs have become smaller and more lightweight.

  • Low Material Costs

You will see a significant difference when you compare the material costs of conventional PCB manufacturing techniques and surface-mount technology. Considering the miniaturization that SMT brings into the PCB world, the material costs are significantly low.

Since small PCBs have smaller components, the material costs reduce automatically. In turn, that drives the price of SMT PCBs downwards, making it a more favorable option in electronics.

  • Simplified Production Processes

The surface-mount technology simplifies the production process to a massive extent. For instance, the mounting technology requires manufacturers to bent, shape, and cut the electrical components before mounting them on the circuit boards.

That automatically reduces the time, energy, and money spent attaching components to the circuit boards. Hence, the process simplifies, making it far more manageable and less time-taking.

  • Better Production Efficiency (and Automatic Production)

Surface-mount technology pioneered automatic PCB production processes in factories. It involves standardization and serialization in the production process. Moreover, it also brings consistency to the welding processes for attaching chip components to SMT printed circuit boards. Thus, the reliability of compact components on miniature PCBs will increase while the rate of component failure reduces gradually. 

  • Improved Signal Transmission Speed

Do you know that SMT brings higher safety density to PCB structures? Although the technology created miniature printed circuit boards, it also improved the safety density. For instance, the solder joints per cm2 can be around 5.5 to 20 as assembly density.

You must realize that high signal transmission speeds will also increase PCBs’ resistance to impact and vibration. This could ultimately result in high-speed operations and better electronic equipment around us. 

  • Better High-Frequency Effects

The distributed parameters of the circuit boards are generally high. However, they reduce drastically when the components attached to the board either have no or short lead. That’s because the absence or negligible amounts of lead causes reduced RF interference.

Conclusion

Learn about printed circuit boards and your requirements before choosing surface-mount technology. You will require thorough analysis and proper planning for successful end-product manufacturing if it includes PCB.

And if you’re planning mass production, make a prototype for testing. With surface-mount technology, you can create simpler designs and compact devices with quicker completion times. However, considering your requirements is best to do a cost-benefit analysis.

Everything You Need to Know About Circuit Board Assembly!

mwcms on September 13, 2021

Most of the electrical appliances that run our lives on a daily basis include about 300 feet of tiny wires inside. This wire is the main component that adds connectivity inside an electrical product. It allows all the other small components in an electrical appliance to work seamlessly together.

The more complex an electrical appliance is, the larger the number of components and the wire inside it. However, you may be wondering where this wire is located. Well, this is where the printed circuit board assembly comes into play.

What is a PCB?

The printed circuit board or PCB is the small circuit board inside most electrical appliances. They are either green or blue and at first glance, they look like ordinary pieces of scrap plastic. But in reality, they are actually a multi-layered board that consists of an abundance of copper wires.

This scrap of flat metal is the surface on which manufacturers will precisely and carefully place all the essential components using expensive heavy machinery. Along with that, small copper wires will connect between the components and provide the necessary connectivity that occurs between all the components. This connectivity allows the components to work together and as a result, this paves the way for an electrical appliance to function.

What is inside?

The printed circuit board consists of ten conductive layers. The top and bottom layers of the Circuit board assembly make for surfaces on which manufacturers will mount components and they also act as multiple antennae. Moreover, each of these components on the circuit board requires plenty of power and ground and the PCB has entire layers that are only responsible for providing power and ground.

They are also aptly named power planes and ground planes due to their specialized role. Other ground planes that make the circuit board assembly serve the purpose of electromagnetic shielding and heat dissipation. The remaining four middle layers carry all the communication traces, which means that they carry all the signal wires.

Each of the conductive layers is copper, and between these conductive layers, there is insulating fiberglass, along with an epoxy resin that protects against the flow of electricity between the layers. A common PCB has a total of ten conductive layers, however, in a more technical and complex application, the layers can range up to 50 or more layers.

On the other hand, you may also find a PCB board that is simpler, with only two layers. Not to mention, on the top and bottom layers of a PCB, you will find a coat of solder mask, which offers a surface on which manufacturers will place components using high-tech machines. On top of the soldering mask is the silkscreen, which is nothing but the ink that indicates the placements for components by marking the circuit board.

The Assembly Process

After all the components of the PCB are manufactured, they need to be assembled before the PCB can go into the production line. This assembly process will involve the application of solder masks, automated component placement, along with the electrical testing of the bare board.

Final Thoughts

Printed circuit boards are more widely used inside computing devices, and since each model of smart phones and laptops along with other devices are different, the shapes and designs of circuit board assembly also differ vastly. Overall, it is fair to say that they are integral components of the modern technical era, and without them, none of the highest technical appliances can function.

 

 

The Process of a Printed Circuit Board Assembly

mwcms on August 30, 2021

The PCB assembly process undergoes thorough and intricate steps. PCB’s being the staple circuit board mechanism in most of the electronic appliances is undoubtedly major components that require perfect assembly otherwise they can be major causes of concern for many industries.

BluePrints and Layouts

The assembly process in factories start with a framework or blue print layout and make their way to the customers. Due to the advancements in PCB production, modern manufacturing units hardly have any workers on the production floor. This is because most of the manufacturing process is subject to automation and efficient machinery.

In the starting stage of assembly, the burr board inserts into the laser marking machine, which marks a serial number on the board so that the board can have a manufacturing label. This process is common in large scale production, but is not something common to all Printed circuit board manufacturers.

Applying Solder Mask

The process initiates with the application of solder to the circuit board. Solder mask is a material that sits on top the circuit as a layer in which you can install components of the circuit board. A specific inspection machine then inspects the circuit board and ensures that it is aligned.

Once the inspection is complete, it applies solder all the way across the surface board in an evenly fashion. After solder application, the solder goes through another inspection to ensure that it is applied evenly.  Once the inspection is complete, the board is ready to undergo the next stage.

Adding Component Placements

The next stage involves the addition of the placements. Machines rapidly add placements on the board that are coming from the reels. This machine includes heads that pick up the reels and attaches them to the circuit board. This reel placement happens for about eight times before the circuit board is ready for the next stage.

After all the components attach to the board, it is then ready for the reflow process. This process is important since the solder needs to melt so that it can adhere and be a good surface that provides mechanical and electrical connections between components and parts.

Reflow process

When it goes under the cooking process of the machine, it comes out from the other side to cool. Cooling process takes place so that all the junctions between the components can form and solidify. This results in the next step which involves testing.

Inspection and Electrical Testing

The final inspection will now ensure that all the components are situated in their correct specific placements so that the circuit board assembly is ready for use.  In this testing, advanced machines identify whether the pins are contacting the pads in the exact location. At this point, the SMT process is in completion.

Electrical testing can have implications that follow two processes. The first involves the bed of nails, which helps manufacturers test at a high volume at a shorter time, however it require expensive fixtures. The second testing method is a flying probe, which is a high mix at a small volume.

If the circuit board assembly includes large BGA components, then manufacturers need to inspect whether the pins are reaching the right layer.  These pins are usually behind each component and therefore, you cannot test those using automated machines. In this scenario, manufacturers will likely use the help of X-ray images and make sure that the soldering and components are adequate.

Parts of a PCB, or Printed Circuit Board

Whether the PCB board is inside an air conditioner, or a refrigerator, you can find numerous different parts mounted on the bare board. The main components that you are likely to find and which are critical for its functioning involve a Fuse, transformer, and a switch. The quantity and types of these components can vary according to the specific electrical appliance.

To Conclude

All of these processes and testing are then finalized by a functional test. As you can see, the process of a printed circuit board assembly is full of inspections and automated machine work. Thus, it is a true reflection of the detailed workings in a mass production factory.

 

Tips and Tricks: Learn to Improve Your Current PCB Design

mwcms on August 4, 2021

Circuit designing can be incredibly daunting when it comes to practical application. Often, PCB designers will make common design mistakes that they can improve, with simple tips and tricks. In this article, you learn how to improve things such as signal integrity, EMI, and so forth.  You will also gain insights over trace widths, via sizes, placements, and clearances between traces.

Use Design Tool Kits

Often time’s people fail to realize the use-cases and benefits of tool kits, and do not utilize them for their PCB design. This is somewhat of a mistake, considering that you can find free toolkits online that can help you make a series of calculations that can help perfect a PCB circuit. It is most useful for conductor impedances, crosstalks, differential pairs, and so on.

Coupling and Decoupling Capacitors

Capacitors can come in as very handy components when building a PCB circuit. They act as timing elements or filters. When you use them as decoupling capacitor, you need to connect them in parallel with the power supply.

Why should you do this? Well, you should not expect power supply of any kind to be flawless. The output from these will have a fluctuating property. Hence, this is where a decoupling capacitor can help. Adding it into the circuit will prevent the fluctuations from the supply to reach the digital pins.

Pull Up and Pull Down Resistors

In digital circuits, the conventional way of feeding input involves using switches or push buttons. When you do that, you run into the risk of leaving the input pins into your floating state. This is where the input prints of a chip cannot detect input logic and ultimately lead to an unexpected outcome.

If you want to avoid this common floating state issue, you can use resistors of specific value to improve your PCB circuit. Resistors such as Pull up or Pull down resistors connect the input pin to VCC, so that it can read, “LOGIC 1”. Whereas, a Pull down resistor can connect the input to the ground, and you can use it to read, “Logic Zero”

Discharge Time of Batteries

Your design needs to be compatible with batteries. The most important tip, when powering your circuit with batteries, is to calculate the discharge time of the battery. This tip is helpful because if you attempt to discharge the battery capacity, more than its optimum level, you run the risk of permanently damaging your battery.

As a rule of thumb, you choice in batteries should have about 1.5 times more capacity than your circuit’s actual consumption. However, make sure to check the datasheet because of the invariabilities within the battery chemistry.

If you are designing a circuit that requires one ampere for an hour, then a battery that holds capacity of 1.5 AH is the best choice for optimum performance.

Wattage Ratings

Most people tend to forget about the wattage ratings and focus more on the resistor value of the circuit. Wattage rating of a resistor refers to the maximum amount of power that a resistor can safely dissipate in the form of heat.  If the dissipation in the resistor exceeds the maximum wattage rating, then the resistor is likely to crash.

This is why finding a wattage resistor that corresponds to your circuits resistance value is a tip that will not only improve your circuit design, but also save it from smoking. Hence, you should pay close attention to the power dissipation of a particular resistor.

To Conclude

Most of the times, it is the small changes in PCB design that make the biggest improvements. Therefore, make sure to keep track of all the small measurements and calculations if you want to optimize your circuit for it to work in its highest capacity.

Tips and Considerations: Learn to Improve Your PCB Design Skills

mwcms on April 26, 2021

Are you a printed circuit board (PCB) engineer wondering how you can learn or improve your PCB design skill? Well, you are in the right place, as this post will give you a brief insight into tips and considerations that can help you polish your skills. 

Most engineers are good at PCB designs. However, they lack some basic professional and personal skills they must master. You must begin with the basics and learn to practice your PCB designing skills with consistency day-in and day-out. 

5 Tips to Improve Your PCB Design Skills

Here are five basic tips to improve your printed circuit board designing skills.

  1. Learning more about the Layers

In case you wish to master the skills of designing a multi-layered PCB, you must have a clear understanding of printed circuit board layers. You must learn to revise your basics and learn about the latest standards and trends to ensure that your PCB design meets all the industry and global standards. 

  1. Remembering the Design Rules

There are numerous design rules that every PCB design engineer must follow. Some of the most essential ones are as follows. 

  • Aim for noise reduction
  • Remember the EMI/EMC considerations
  • Remember the thermal integrity considerations, i.e., dissipation of heat because of the power circuits. 
  • Remember the power integrity considerations, i.e., power loss in its path
  • Learn to design for test and add test points at several stages of design. 
  • Follow the design for manufacturing ideology. Always consider track width, drill size, clearance, etc. 
  1. Learning to Use PCB Designing Software 

As designing technology has evolved, using PCB design software is common. In case you are not good at using software, you must polish your skills to draw components, schematics, and printed circuit board layouts. 

There are several PCB designing software solutions available in the market. However, you must pick a few that are common in your industry. If you are enthusiastic about learning more than one design software, then this will give you a competitive edge over other designers and engineers when searching for a new job. 

  1. 3-D Modeling

While you learn to design a printed circuit board on software, do not forget to add a 3-D modeling feature into it. This will allow you to see an almost real depiction of your PCB design before manufacturing it. 

Moreover, this will also allow you to detect any design errors and help save back-and-forth revisions with the PCB assemblers. This will translate into lower cost and time efficiency. 

  1. Learning to Review Thoroughly

So, you have learned the standards. You know the layers and know how to use software to create a 3D model of your printed circuit board. What is next? 

You must always learn to improve your attention to detail. This is very critical if you wish to get your PCB design right the first time. This will again save you from a lot of hassle in the future because the tiniest flaw in the design may result in several revisions and sometimes the overhauling of the entire printed circuit board design. 

Here, you can also learn about the basics of documentation and aesthetics. This will allow you not only to write how the components’ placement should be but also customize how the PCB design must feel and look. 

The documentation part will allow you to clearly label where each component and connector must go and how it must look on the printed circuit board

 The Take-Away

Learning all of the above skills will allow you to improve your PCB design skills as well as learn how to document the guidelines for the assemblers. The more elaborate you are in your design, the better the results.  At Nova, we are always updating and improving our skills. Reach out for a consultation today.