Tag Archives: SMT assembly

Metal Core PCB Board

Metal Core PCB Board

As the electronic industry grows, LED equipment is also becoming more available. And wherever the LED comes, you will see the metal core printed circuit board as basic material. The metal core printed circuit boards are doing well in the automobile and lighting industries, and you can see the results as well. We are getting more efficient lights in the form of light-emitting diodes (LEDs). By efficiency we mean the product is providing better functionality for the possible longest time as well as the cost is also relatively lower than in the past. Now have a look at the lighting sector and LEDs. They are five times less costly than any other light and also provide the best efficiency. But if we see the core functionality of how LED is working then you will notice that it is heat is made from a very small part of the input of electrical power and other electrical devices are also involved. It may sound difficult to concede all the efficiency and get a hundred percent result as the heat is dissipated and thermal loss is happening.

Moreover, it is also difficult to get complete efficiency from the LED light functionality. To overcome this problem and in order to get the best outcome, a solution was proposed. This solution forced the designer to use metal core printed circuit boards in the design of light-emitting diodes. Metalcore printed circuit boards have improved the electronic industry by decreasing the loss of thermal power. Moreover, the main role of the metal core printed circuit board is in the thermal sector which we will discuss further. Now let us understand what metal core printed circuit boards are.

What is a metal core PCB?

As a clear form name, a metal core printed circuit board has the metal in its base material, and this base is used when we need to spread heat on the bread. A metal core printed circuit board is also named thermal PCB or metal-backed circuit board because it deals with the thermal power of the circuit board. The metal base material is used to oppose the typical FR4 printed circuit boards. And the metal core helps redirect heat away from the components which maintain the heat and temperature of the board.

The metal core PCB is designed with a particular standard thickness depending upon the need of the circuit board. The metal used to cover the side of the printed circuit board is usually made of copper and aluminum. Moreover, a circuit board may have metal in the reference of the metal core in the back and in the middle of the board. During the operations done in the circuit board, a large amount of heat is built up in the circuit board that needs to resolve in order to save the other fragile components of the board. As mentioned before, the metal core helps the board in maintaining a way that redirects heat away from the components. These components are usually the heat sink backing areas and metalcore areas. CEM3 and FR4 are alternated by the metal core in the metal core printed circuit board (MCPCB). So, we can say that metal core printed circuit boards are designed for thermal management that’s why they are also known as thermally printed circuit boards.

Structure and thickness of metalcore PCB material:

There are different metals available for the metal core choice. Mostly used are copper aluminum and a mixture of some special alloys. But as a matter of fact, aluminum metal core is the widely used metal in thermally printed circuit boards. You may find a request for some other metals such as brass and steel, but these metals are not recommended by experts as they are not the best alternative to copper and aluminum.

The thickness of the metal is kept enough that it can dissipate the heat well. The most common thickness that is recommended for the metal is from 30 mils to 125 mils. The copper metal thickness can range from 1 oz to 10 oz. it needs to be considered that metalcore or metal-backed is the thickest material of the circuit board. It is recommended to use 1mm, 1.5mm, and 3mm metal plates. We know that hardware needs to be mounted on the metal plate. Moreover, the circuit needed to maintain its flat structure and rigidity. That way the metal plate should be thickest enough that it provides the above-mentioned characteristics.

In most cases, aluminum is preferred over other metals because of its special characteristic. As you may already know, surface mount technology is used in aluminum. Aluminum plays well with the heat dissipation in the circuit and deals with it effectively. It is cost-effective and reduces the size of the product which is also a good approach. Aluminum prolongs for a lifetime, and it also helps in reducing the temperature of the operating time and provides the reliability of the product by improving the density power. If circuits need to be mechanically endured that aluminum metal core is a way to go.

Benefits of metal core PCB:

There are several benefits of the metal core printed circuit boards other than better capacitive coupling, higher power density, and higher electromagnetic shielding. This can be further improved by using thermal vias. Following mentioned are additional benefits of the thermally printed circuit boards:
Heat dissipation: the heat dissipation in the metal core pc board is very good. Heat efficiency would be removed from all the integrated circuits in the metal core printed circuit boards.
Thermal dissipation: higher thermal conductivity can only be achieved by the thermally printed circuit board. It keeps the heat away from the circuit as much as possible, so the circuit damage is reduced. High-density circuits are being managed by high powers in the metal core PCB. the aluminum substrate is the best choice used for this purpose.

Strength and stability: better strength and stability can only be achieved by metal core printed circuit boards. Heat dissipation is concerned with the development of LEDs. As the LEDs are directly mounted over the surface of the printed circuit boards that’s why stability and reliability are required by the circuit directly.

Applications of metal core PCB:

Metal core printed circuit boards are designed for applications that needed high functionality in the early 1960s. In the present age, it is the most widely used technology in the printed circuit board industry. The metal core PCB is selected because almost every device needs to reduce the temperature of the operating system. Moreover, thermal conductivity is achieved by the dielectric material used in metal core PC Board Fabrication.

What in the metal core printed circuit board is transferred quickly because of the insulating material and the reduced thickness of the metal plate? It is a great alternative to the FR4 as the thermal value provided by metal core PCB is nearly 2W/MK which is much higher than standard F4 printed circuit boards. As long as the dielectric layer is thin, the results would be the best in the metal core PCB. The path of the heat dissipation can be kept as low as possible which is more conductive if we see it from a thermal point of view as compared to the dielectric. So, there is a vast list of applications in which metal core printed circuit boards are being used. Some of them are mentioned below:
• Automobiles and heavy machinery
• Light-emitting diode (LEDs) and system automotive applications
• Photovoltaic
• Lighting streetlights and in the street safety applications
• Telecommunications
• Power supplies, power converters,
• Industrial and high voltage regulators
• Backlight unit applications
• Hybrid application
• Electric motor control application

As metal core printed circuit boards are providing efficiency and functionality so they’re taking a buzz in the electrical industry. It is being said that metal core PCBs are going to develop much more than at present. Despite their present usage in the market, experts have a common suggestion that metal core printed circuit boards can be a good choice for many other electrical equipment.

PNCONLINE is providing top-notch PCB solutions for your requirements. Just write us at sales@pnconline.com to get your Board design and SMT assembly done.

Printed Circuit Board Signal Conditioning Process

Printed Circuit Board Signal Conditioning Process

The process of data acquisition is known as signal processing. This acquisition is done by an instrument which is known as the signal conditioner. There is a conversion of signals that happened in this process. The signal conditioner converts the signal from one form such as electrical or mechanical to another form. The input signal is converted into the output signal in the signal conditioning process. Now the question may arise why do we need to convert the input signal into an output signal? The simple answer is that the signal needs to be amplified.

This amplification helps the signal to be converted into a compatible and easy-to-read form. This form of signal helps in data acquisition and machine control. Analog signals are converted into digital signals but before that, correct preparation is made. In the signal conditioning process, we manipulate a signal in a way that it can be converted and further proceed for the next step. Mechanical and environmental measurements are made in many electronic acquisitions for the measure. These measurements are done with the angle of specific sensors such as temperature and vibrations. But these sensors cannot work accurately for the measurement of the signals if the signal conditioning is not compelled yet.

Certain signals tend to have a very low voltage level. For these types of signals, amplification is required before they can be digitized properly. The best example of these signals is thermocouple signals. Some of the other sensors such as accelerometer, strain gauges, and resistance temperature detector cannot work until the excitation to operate is not completed. All these technologies are the best example of signal conditioning.

Because of its importance, we can say that signal conditional can be considered as the fundamental block of modern data acquisitions taken in consideration during the PCB design step. Physical measurement is the end goal of the data acquisition system. The following basic components are achieved by the signal conditioning process:

• Analog to digital convertor
• Sensor
• Signal conditioning
• Computer with DAQ

Use Of signal conditioning:

As discussed before, the basic task of signal conditioning is the conversion of the signal. The signals are converted from the input form to the output form. Most commonly, the input signals are of the electric type. Now why the conversion is required. This conversion is needed when the conventional signals cannot process the actual signal easily and it needs to be converted so that interpretation can be done correctly.

Frequency, electric charge, AC voltage, electric current, DC voltage, and current are basic signals that are accepted by the signal conditioning process.

A data acquisition system cannot work until it is connected to several signals and a wide variety of sensors. The arranged process is happened for the signal converting. The analog signal is taken by the signal conditioner for better manipulation. Once the signal is manipulated, it is then sent to the analog to digital converter system. The analog to the digital converted system is the end resource and it helps in digitizing the signal so it can be used in further processing. The basic purpose of the signal conditioning business is the conversion from analog to digital signals.

The digital domain is achieved by this process and this domain is then represented, displayed, stored, and analyzed. Input can be measured from a sensor that is used to measure strain, temperature, resistance, and acceleration. Moreover, the input can also be achieved by relays, switches, encoders, and clocks. A huge number of varieties can be interpreted from signal conditioners, this variety of signals include the output type.

There are some basic functionalities of the signal conditioning process. We will see the functionalities later. First, we need to understand the process of signal conditioning after the Printed Circuit board Fabrication is done.

Process of signal conditioning:

Following are the steps that are included in the signal conditioning process. The detail of every step is given for better understanding.

Step 1: Adjustment of a signal according to noise ratio:
The signal is adjusted to the noise ratio with the help of amplification and attenuation. In the electronic dictionary, you can say that amplification and attenuation are two opposite subjects. The deterioration of analog signals happens because of the background noise in the transmission process.

There comes the term signal-to-noise ratio. This means the signal strength ratio to unwanted background interference. This ratio is then increased with the help of amplification by magnifying the voltage level of the input signal. For example, in amplification, a signal of 0-1mv is converted into 0-10v.

On the other hand, in the attenuation process, the input amplitude is decreased. This process is done so that the signal can be fit in the optimal range of the device digitizer.

Step 2: removal of voltage signal for the prevention of equipment from damage:
The filtration and isolation of the input signal are required by the signal conditioning process. This is done because the unwanted background noise that is unwanted needs to be removed. Moreover, the removal of voltage signals that are far beyond the in-line digitizer is also compulsory.

There is a considerable difference in filtering and isolating processes. The filtering is done when noise needs to be rejected from a predefined frequency range. We can say that the isolation process is somehow similar. But the difference is a protection step of data acquisition and control system form the from voltage spikes is done. These voltage spikes can damage the entire data acquisition system.

Step 3: using controlled current or voltage for excitation technique:
Transducers and their subtypes require the excitation process. The operation of an active sensor is done with the help of the external sensor. A few types of signals that require external power to proceed further are strain gauges, accelerometers, transmitters, resistors, thermistors, and RTDs.

Step 4: signal linearization
Sometimes a signal cannot exhibit a linear relationship to the actual measurement. These types of signals can also be produced by some sensor equipment. To overcome this problem, we need a linearization process. As clear from the name linearization is done to optimize this signal according to the actual measurement.

The voltage of the input signal is mapped with the corresponding value requirement by physical measurement. Linearization is a very common signal connection process. The most important use of linearization is in industrial temperature measurement.

Now you have understood the process of signal conditioning in depth. Above mentioned steps need to be followed step by step for better signal conversion. Now it is necessary to understand the basic function of signal conditioning. How it is done and what are the benefits of signal conditioning.

Let’s understand the functionality and the benefits of this process now.

Functions of signal conditioners:

As we have discussed before, the main functions of signal conditioners are filtering, isolation and amplification. If these steps are not done correctly then inefficiencies and inaccuracy can happen. These can lead to incorrect output, loss of data, and other problems. So, the question arises how you can avoid these problems?

Now how would you know which type of signal conditioning is best for you? Well, the type of input signal you are going to use for processing will decide this. The other factors that make an impact on the type of signal conditioning process are desired type of output, available power for isolation in the quality criteria of the signal.

Now let’s understand the basic PC BOARD functions such as accuracy, flexibility, and the isolation required by signal conditioning.

Accuracy:

Accuracy is the main thing to be noticed in the signal conditioning process. There is a broad variety of accuracy along with signal conditioning. There is a direct relation of accuracy between the conditioner and the accuracy of the other equipment. For example, the sensor that is used to provide the signal. An extremely accurate signal conditioner cannot perform well if the sensor is used in the process is not precise and working correctly. So, in a nutshell, you can say that to get the highly correct and efficient output, every degree of accuracy should be the same in the signal conditioner and other parts of the system. Otherwise, the device and cost would be wasted with a high level of precision.

Flexibility:

As clear from the name flexibility in the signal conditioner means processing with a number of signals. A wider range of signal types can be processed with the flexibility feature. It is often considered as an additional advantage. Many designers and manufacturers add this feature to the product just to increase its functionality and efficiency.

Because if the device is dealing with a wide range of signals, it is likely to be more precise and calibrated for sensors. The replacement and change of other important parts of the system can be done with the help of flexibility. This will not affect the other part of the system.

Isolation:

Isolation is used in the signal conditioning process at more than one point. As a clear from the name, this process isolates the components and encourages that there is no interconnection between electric and other parts of the devices. The isolation process is required because it will enhance the common quality of the system. Moreover, the signal that needs to be isolated would also be decided according to configuration.
Should you have any further questions regarding the Signal Conditioning Process, feel free to contact us at sales@pnconline.com

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What is the BGA of PCB Assembly

What is the BGA of PCB Assembly?

What is BGA (ball grid array)?

Ball grid array (BGA) is used in integrated circuits for circuit mount packaging. Ball grid arrays are used when we need to mount the devices permanently such as mini processors. The connections are made on the bottom of the SMD ball grid arrays. A solder ball is present on every single pin. A uniform circuit for the grid is also made on the circuit for better connection. The size of this grid varies from 1.27mm to 1.0mm. Although there are hundreds and thousands of component connections present on each layer, the number of routable pins per layer is limited. The via and the routed connection should be applied to the inner pion of the layer as this technique is known as DogBone. There is another technique known as via in pad which is used when the circuit needs the pads in the solder masking and the pitch of the circuit is relatively small. Ball grid array is recommended because it provides more interconnection pins. The solder ball is also provided with every pin.

These pins can be put in flat, dual, and inline packages. The distribution of connection on the even and uniform circuit is compulsory. The bottom perimeter is also used sometimes but the whole button surface is more preferred. The process of the ball grid array is critical and needs to be done carefully while following the instructions. Soldering in a ball grid array is done in an automated process and needs complete control over the process. That’s the reason the ball grid array is not recommended for socket mounting.

The thing that needs to be noticed in the ball grid array is there is no direct lead that connects the ball grid with the circuit. Instead of leads, the ball grid uses solder balls to make a connection with the circuit and to pass the electric current. There is a physical connection made between the substrate and these balls during the smt assembly process. The physical structure is connected to the substrate by a wire which is responsible for the flow of the current. The conductive traces present in the trace are responsible for sending electric signals. This flow happens between the bonds and the substrate and the base of the balls.

There is a term known as ball grid re-balling. This technique allows the reusability of the component. That’s the reason it is most recommended. The scrapping rate is low in rebelling. This process is cost-effective and time-friendly because the ball grid package can be removed. This also saves the material of the entire process. In fact, the cost can be decreased in a high ratio if one selects to reuse on a ball grid array.

Why choose a ball grid array for PCB?

Ball grid arrays are used in printed circuit board packaging because of less density and low cost. Undersize chips are used for the interconnection of the circuit. On the other hand, there is another chip known as a conventional chip in contrast which uses the perimeter section for the interconnection. The printed circuit board has relatively high performance and more space for connection.

Moreover, the thermal resistance of the printed circuit board is low. It offers high performance at high speed. Printed circuit boards made from this technique are more reliable.

Types of ball grid array:

There are three types of ball grid arrays. These types are mentioned below:
• Ceramic ball grid array (CBGA)
• Plastic ball grid array (PBGA)
• Tape ball grid array (TBGA)
Each type is crucial in the processing and making connections and each part has its detriments. The selection of the right solder is important for better performance. That’s why relative types should be chosen for certain work.
Let’s understand the functionality of each type in detail.

Ceramic ball grid array (CBGA)
This ceramic package is used when the substrate used is of ceramic type. There are many further types of packages that come under the umbrella of ceramic grid arrays. For example, CCFA and LGA. The ceramic material is used when the temperature rate is high as the base material is ceramic. These types of chips are used in computer mini processors. Multiple layer packages are used in this type. The flip-chip method is preferred over the wire bond for the interconnection of the die. The reliability of the ceramic grid is increased by adding ninety percent lead with tin in ten percent quantity.

The difference in thermal coefficient of expansion in the substrate is also controlled by using this method. The packaging density and heat dissipation is high in this type. But the manufacturers have to compromise over the thermal compatibility as it is quite low for a printed circuit board. Moreover, the ceramic process makes the cost higher. So, this is not a cost-friendly type.

Plastic ball grid array (PBGA):
As clear from the name, the base material for the body package is plastic in this type of ball grid. It offers high density and solves the cost issues by combining the over-molded pas array carrier and glob to pad array carrier. Sixty-three percent of tin and thirty percent of eutectic tin is combined in the solder balls. The substrate is made in the sense that it can deal with at least 150 degrees Celsius of temperature.

The size of the normal package of the plastic grid is almost 17/17. 0.8mm to 1 mm is the ball pitch so the average range of the ball count would be from 206 to 976 balls. Plastic grid arrays are sensitive to humidity. But they perform better in the case of electricity. The thermal compatibility in plastic balls arrays is excellent which is a good choice for a printed circuit board.

Tape ball grid array (TBGA):
Tape ball grid array is used for a thinner base purpose. The electrical and thermal performance is optimal in the tape grid while the version of the ball grid is relatively thinner. The wire bond and flip-chip technology are used for facing up and facedown wire bonds respectively. This increases the dissipation of heat. The printed circuit boards are reliable, flexible, having more space and fine lines in this type of all grids. Tape ball grid arrays are also very sensitive to humidity. They are less dependent, and the overall cost of the connection is also low as compared to other types.

For having great manufacturing of printed circuit boards, the designer should have enough knowledge about ball grid arrays. Because the internal structure will depend on the design and correct use of the ball grid surface.

Benefits of Ball Grid Array:

Following are the core benefits of the Ball Grid Array:
• Ball grid arrays are a new technology used for interconnection in the circuit. This is done by using tiny spheres instead of conventional pins. So, this increases the benefits of the BGA in printed circuit boards.
• By ball grid array, the space of the printed circuit board can be managed properly. This package involves a smaller number of components and footprints. The space for the custom printed board can be increased and this will enhance the efficiency of the circuit board.
• The ball grid arrays improve the profitability of the circuit in the manufacturing process. These packages are kept on a large surface, so the soldering of the large area is easier.
• The manufacturing yield will enhance and then this will enhance the performance of the printed circuit board. The rework process is easy when the manufacturing is done in a large area.
• Ball grid arrays improve the thermal and electric conductance of the circuit. As the circuit is of small size so the heat can be dissipated easily. But the most heat can be transmitted on the board when the silicon wafer is present on the top surface. In other cases, the silicon wafer can be connected on the bottom side, then the other side of the silicon wafer will perform the role of best available space for heat dissipation.
• There is less damage in the circuit if the ball grid array is present because of the use of soldering balls.
• The soldering technician will be at ease when dealing with the ball grid array because it aligns itself on board along with stencils.
• The interconnection between the die and the pad is low and this improves the electrical conductance.
• The connection present on the bottom of the chips is shorter and assures the speed and performance of the circuit board.
• The pins used in the process are fragile and very thin in size. This increases the ratio of damage. And we already discussed that this damage is nearly impossible to overcome. But the ball grid array connection makes sure that the process is reliable and there is no chance of damage and break. As a result, the connection is more reliable.
• The overall cost of the connection will be reduced. All the benefits mentioned above will help in decreasing the cost of the process. The defect rate will also be reduced and the material and resources for the connection can be saved.

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Laminate Material for PCB Board Fabrication

Laminate Materials for PC Board Fabrication

Printed circuit boards are now a common part of our daily routine. We are using PC Board Fabrication in almost every electronic device we are using for our work and entertainment purposes. Whether it is a mobile phone, or a screen, or a remote for television, every device consists of a printed circuit board. That’s the reason understanding its working is kind of crucial these days.

When we discuss printed circuit boards, we need to understand their layers. PCBs have various layers, and these layers are concerned with their working. These layers will vary according to their working. For example, most multilayer PCBs are used when the device is complex, and we need multiple functionalities. Now let us understand how we do lamination in printed circuit boards and how it is related to layers of PCBs.

What is Lamination in Printed Circuit Boards?

As we have discussed before, there are many types of printed circuit boards. They are both single-layer and multiple layers depending upon the functionality of the device. So, for multiple layers of printed circuit boards, lamination is required.
We can say that lamination is a process in which successive layers of materials are built and then binding those layers to strengthen those layers to protect different substances.
One of the important steps in building a printed circuit board is lamination. Circuit board manufacturers do the lamination process to make sure that copper is not conducting a current or signal inadvertently. There is a substrate in the printed circuit board that plays the role of canvas on which all the components of printed circuit board assembly are attached. Copper is laminated to that substrate. Lamination is an integral part of printed circuit board manufacturing. The lamination process will vary according to the requirement of the circuit board. The type of lamination you choose for your circuit board will decide its reliability and performance for the particular device.
Now we have understood what lamination is. Let’s understand the role of fabrication and then we will see how both these terms are related and how the lamination process takes place.

What is Printed Circuit board Fabrication?

Different layers of the circuit board are placed together on a particular surface pattern to be used in printed circuit board manufacturing. Fabrication is the method of assembly for circuit boards that are used in different electronic devices such as computers and phones. fabricated PCBs are used for customer special products. Sometimes the manufacturers fabricate the circuit board in the house or sometimes they hire a third party to do so.
It is being said that fabrication is the skeleton of any circuit board. Why is that? Fabrication is the process in which we give or transform the sketch of the circuit board into a structural existence. The specifications are provided for the circuit board and fabrication is a way to transform the sketch into the physical design. There are few techniques that are used for this purpose. We will explain those techniques later.
Lamination is the backbone of circuit board fabrication. For better understanding, let’s discuss the types of laminations.

Types of laminations:

If you are not aware of the types of printed circuit boards then you are more likely to face difficulties in designing the circuit board. Types of laminations in circuit boards will help you analyze the designing and the development stages your circuit will go through. Hence the type of lamination will decide the overall reliability, stability, and performance of the printed circuit board. There are four layers of a simple printed circuit board that are compulsory for basic performance. These layers are:
• Substrate
• Solder mask
• Copper
• Silkscreen
And then comes the lamination which is used to hold these layers together. The lamination is done under pressure and temperature. Thermoset resins are used in this process to create a uniform thickness that is required for the process. Typical numbers and letters are used to show the type of lamination which basically shows the characteristics of the product used in lamination. These characteristics are dielectric constant, the tensile strength of the product, shear strength of the material, loss factor, glass transition temperature, fire retardant, and the rate of change of thickness with temperature. For example, if you see FR-4 then it is sure that FR-4 is the most used product in the lamination process. There are different types of lamination that are done in printed circuit boards. The explanation is given below:

1. High TG epoxy:
High TG epoxy is used for multilayer printed circuit boards, and it is most suitable for them. as we already know that multilayer PCBs are used in complex devices from which we need higher functionality. For better epoxy rate in those PCBs, high TG epoxy lamination is used. There are certain characteristics of high TG epoxy. Such as high chemical resistance and increasing heat. TG epoxy is used when we are concerned with tolerating high heat. The temperature in this lamination is similar to the melting point. These characteristics will increase the rigidity of the circuit board and the performance. This Tg is best for ROHS PCB assembly.

2. FR-4:
You have probably heard FR-4 in the world of lamination before because it is the most widely and commonly used material for lamination. The reason for its popularity is its characteristics of a good trench to weight ratio. This material is flame-resistant which makes it more reliable. The mechanical, electrical, and physical properties of the material stay maintained when there is an increase in temperature because of flame-resistant properties.

3. High-performance FR-4:
As clear from the name, high-performance FR-4 is used when we are supposed to make a multilayer and multiform complexed purpose printed circuit board. TG is the temperature variation that is higher in high-performance FR-4. This increase results in high stability and maintainability. Also increase in TG performs better in high-frequency circuits because of low dielectric powers.

4. Polyimides:
Polyimides are also used in multilayered printed circuit boards. Polyimides are used in lamination where we need extreme environmental stability. Rigid, flexible, and high-density circuit boards require polyimides in the lamination process. Mechanical, thermal, and chemical properties of the material can be increased by using polyimides. Due to these properties, polyimides are highly recommended for heavy applications such as military, aerospace, consumer electronics, and automotive.

5. BT Epoxy:
If you need high standard thermal, electrical, and mechanical properties in printed circuit boards then BT Epoxy is the best available choice among all. This laminate is designed to use in multilayer PCBs, and it helps in bond strength at high temperatures. BT epoxy is recommended and suitable for lead-free printed circuit boards.

6. Teflon:
There are particular issues with using Teflon in a printed circuit board that results in conventional board shops. But despite this fact, Teflon is highly recommended and suitable for high-frequency applications. Teflon is available in many different types. The most used type is woven Teflon with glass. This material is very flexible and makes SMT assembly a little more difficult.

7. Copper Clad:
Glass fiber and wood pulp paper are used in copper-clad laminators as a reinforcing material. High voltage circuits require copper-clad laminates. These circuits are mostly based on some kind of specific size, appearance, specification, chemical, environmental and physical performance.

We have understood the types of lamination. As we know that fabrication is done by the process of lamination. To better understand the process of lamination, we need to understand the techniques. There are certain techniques to perform lamination for fabrication in printed circuits boards. There is a stage in fabrication in which inner layers and foil are heated and pressed into the circuit board. Lamination is required for this stage. Different methods and materials will be used in circuit board fabrication depending on the requirement of the printed circuit board.

Teflon Microwave:

Teflon microwaves laminates are used in circuit boards where high-speed signal flow is required such as RF., they are ideal PCBAs for radio frequency applications because of their high properties of minimal electric loss, reliable dielectric constant, and tight depth tolerance.

Multilayer PCBA:

In this method of lamination, multilayer PCBA is fabricated in several layers. Thin etched boards and trace layers are used in this lamination that is then bonded. Internal layers are placed under high temperature and pressure and are heated intensely. The Circuit board is then laminated with dry photosensitive resistance as the printed board cools down slowly and pressure also releases gradually.

Sequential Lamination:

The most modern technique for PCB fabrication is sequential lamination. This technique is widely used for PCBs having two subsets. An insulating material is placed between the layers of PCB in order to create a subset of PCB. Then the standard lamination process of circuit boards is implemented. This method requires more time and cost for the process. But this is the fundamental technology that is being used for the fabrication process in multilayer PCBs.

High density interconnects (HDI) printed circuit boards are not possible to develop without sequential lamination. HDI is now the most advanced place for electronics so sequentially implementing lamination can ensure the benefit of manufacturers.

PNCONLINE is the market leader as a circuit board manufacturer and will assist in the overall assembling process.

Interested to know more about PCB laminate materials? Just write us now at sales@pnconline.com.

PC Board Fabrication for High-Speed Circuits

PC Board Fabrication for High-Speed Circuits in Pcb Assembly

PC Board Fabrication for High-Speed Circuits?
PC Board Fabrication

If you have seen printed circuit boards (well, I am sure you have seen one) then you must wonder how they are made and how they are managing your electrical devices. Nowadays, a multiple-layer printed circuit board is managing the most critical electronic devices. From your laptop to your phone and other devices are relying completely on printed circuit boards. Printed circuit boards may seem uninteresting to you but once you get deep into it, it’s an interesting and worth knowing subject. Let’s imagine, how a printed circuit board is working in the device you are using right now, and it will boost your interest. Now the question may arise about the manufacturing of the circuit board. How is a printed circuit board manufactured and prepared?

There are few rules in the designing and manufacturing of printed circuit boards that need to be followed. The material being used in the circuit board matters a lot. The main purpose of the material is to provide insulation between the conducting layers of the copper foil and pass electricity. Essentially four basic layers need to be followed in manufacturing a printed circuit board. The format of these layers is:
• Silkscreen
• Solder mask
• Copper
• Substrate

Initially, there were only two choices available for the PCB’s. One is a rigid circuit and the oter is a flexible circuit. Now as the electronics industry has been developed the boom in printed circuit boards can also be seen easily. Now we have a choice of different printed circuit boards for different devices. For example, various frequency ranges and antennas.

But the thing that needs attention is that the base material used in the manufacturing process of printed circuit boards is still the same. And the material used as a base for the printed circuit board still falls into the rigid category of the printed circuit boards. Now let’s understand what a substrate is.

What is the substrate?

Let’s imagine a building. What is the base of the building on which it is relying entirely? The ground, right? Similarly for the manufacturing of printed circuit boards, we need to build a base first. And the same as the building should have a reliable and strong ground, the printed circuit board also requires a good and efficient material with a number of characteristics in order to stand out in the world of electronics.

The substrate is the first physical layer of the circuit board on which the traces and components are relying. If you want to manufacture a reliable and high-quality printed circuit board, choosing the right and recommended material for the substrate layer is the first step you should go for. There are a variety of choices available when you get to choose the material of the substrate. But first, let’s understand why it is important to give this much attention to substrates.

Importance of substrate

There should be a solid shape and structure for the PC Board so that the other layers, traces, and components can easily rely on it. A strong canvas and platform are required to better hold all the components. The overall performance of the printed circuit board would be affected by the quality of the substrate. A soft substrate offers more space for designing options. On the other hand, hard and rigid substrates increase the durability of the circuit board. Similarly, if we need multiple designs on the printed circuit board then we may use multiple substrates for each layer. As we need to be concerned about the non-conductive material so the substrate decided should be able to withstand heat and dielectric constant also.

Now let’s have a look at different types of substrate with an explanation so you can understand how substrates are suitable in particular circuit boards. Moreover, the substrate is the reason for the stability of the printed circuit boards. It protects the board from bending by providing it with a hard or flexible surface. For example, the computer motherboard is probably the most common substrate you can see now. The motherboard is a multiple-layer printed circuit board. You can see that other components and traces are connected to the surface in such an efficient and best way.

Rigid Substrate:

As we have discussed before, the rigid substrate is always a good choice when we want a strong and dielectric circuit. Also, the rigid substrate can cross up to 350 degrees, so it is a noteworthy operating temperature. Rigid substrates are preferred when you want a PCB in a way that it can be repaired and maintained easily. It is easy to mark the affected area because of the clear view of the board. Rigid substrates are the best choice for critical situation usage devices for example LEDs used in medical surgeries. Ceramic-based substrates are the most common these days. Common examples are aluminum nitrate and aluminum. Rigid substrates offer high thermal stability and low expansion and are easier for the pcb assembly process.

Soft Substrate:

There are renowned benefits of using soft substrate in a printed circuit board. Soft substrate act as a shield in a hazardous environment. You can make a corrosion-proof, waterproof, and shockproof printed circuit board by using the soft substrate. This advantage is not provided by most rigid substrates. The dielectric material or glass material can be protected by epoxy coating around the filler. The soft substrate also provides resistance against chemicals and radiations. The melting point is high in them. Soft substrates have made the wearable concept possible. It is now possible to enable printed circuitry in tight areas just because of the soft substrate used in it. Although flexible material used in circuit boards is expensive, it provides better functionality by reducing the weight of the overall circuit.

Flex-Rigid substrate:

Sometimes a PCB requires easy fixation. Lightweight can also be a condition to follow. In this case, flex-rigid can accommodate the requirement perfectly. Specific flexible substrates such as R0400 are used in circuit board manufacturing; they are simple to machine and precision built. They are the most lightweight substrate, so it is possible to reduce weight and space up to 50 percent. Because of these features, flexible substrates are the best available choice for most printed circuit boards.

FR-4:

If you want to build a complex and multilayer printed circuit board then FR-4 is the way to go. They are also known as fire retardants, and they offer high resistance against flames because of the bromide present in them. There are several subcategories of FR-4 such as TG and FR-4 Roger. The other advantage of this substrate is that it is cost-friendly. Highly optimal performance of microwave frequency in the printed circuit board can be achieved by using RF-4 because of their strength to weight ratio. This is also a reason for their affordable design.

Now we have analyzed the reasons why we should go for good substrates. Let’s also understand the materials of the substrate. Because the quality of the substrate plays an important role in deciding the efficiency and reliability of the PCB as well as the end product.
Ceramic substrates are usually preferred because of the high magnitude of the thermal conductivity as compared to conventional printed circuit board material.

Commonly used substrate materials are Al2O3, AIN and FRx. alumina is preferred because it offers high resistivity, the best dielectric strength, good thermal and corrosion stability, and the best mechanical power. Its major disadvantage is a delay in propagation signal because of the relatively high rate of dielectric constant. It is also difficult to draw away heat and the reason is low thermal conductivity.

That’s why ceramic materials are under development. The main purpose of these developments is to improve the existing material. Integrated circuits are one of the best examples. As they perform complex functionality, it is important to build a printed circuit board with multiple layers. The low dielectric material is used in these circuits.

Similar polyimide is also used as a substrate in printed circuit boards. It offers wide temperature ranges and better chemical resistance. Its electrical properties are also good. Typically, these PCBs are used in cameras, antennas, entertainment devices, calculators, and instrumental panels. The other material that is recommended in the substrate is PTFE, this offers low dissipation and maximum temperature stability and would require a fixture for the printed circuit board assembly process. These are used in antennas, the aerospace industry, and power amplifiers.

There are many other examples of the best substrate materials that many industries are using for manufacturing better-printed circuit boards. The end goal is to provide stability and reliability under severe conditions. Also, it is preferred to use substrate material that is beneficial for critical industries and helpful in industries such as medical and aerospace.

The entire printed circuit board is relying on the substrate as it provides the basic foundation. The other components such as silkscreen, copper foils, and traces can do good if the basic physical layer is good. That’s the reason you should take some more time in deciding your substrate material and type. This will be a key to your PCB’s better performance.

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