CEM-1 PCB

In this guide, you are going to learn everything about CEM 1 PCB.

So, if you want to be an expert in the CEM 1 PCB field, this is a guide you must read.

It covers both basic and advanced concepts of CEM 1 PCB.

What is CEM 1 PCB?

This is a low-grade base material used in making printed circuit boards. It is mainly used for making PCBs with one side.

Even with the developed technology, this material is still widely used because of its low cost.

It is a composite material on a cellular basis that has a layer of glass fiber laminate at the surface. A CEM-1 normally has a milky white color or milky yellow color.

The limitation of CEM-1 is that it can only be used to manufacture a single-layer printed circuit board devices.

This material is cheaper in comparison to FR-4 material when it comes to the production of a single layer PCBs.

So, if you are looking for a printed circuit board for low cost electronic devices, then try the CEM 1 PCB.

CEM 1 PCB

What is the difference between CEM 1PCB and FR1 PCB?

CEM-1 is a paper-based laminate. It’s made by combining two layers of woven glass fabric sandwiched between paper cellulose to form a single-layer PCB.

Therefore, it is only ideal for one-layer printed circuit boards.

On the other hand, Flame retardant (FR) 1 has a high TG of 130^oC.You can as well use it to produce single-layer PCBs. This is because it is not good for plated through-holes passing, just like CEM-1.

But, before choosing either FR 1 PCB or CEM-1 PCB, you should analyze a range of factors such as:

• Cost implication
• PCB fabrication process
• Application requirements

Which materials are used in the manufacture of CEM 1 PCB?

CEM 1 PCB is made from composite material on a cellulose basis, which has a one-layer of glass fiber laminate. It is made by combining two layers of woven glass cloth, epoxy resin, and phenol compounds.

Paper cellulose is placed in between the layers and is impregnated with epoxy resin to form one layer PCB.

The material is more fragile as compared to FR-4, although it is cost-effective in producing one-layer PCBs.

These materials have good mechanical and electrical properties. They are normally milky white or milky yellow.

CEM -1 is also coated with copper, which is a good heat conductor.

 CEM 1 Printed circuit board

What are the Electrical Properties of CEM 1 PCBs?

The electrical properties of CEM-1 PCB are different depending on the type of epoxy resin used to manufacture it. It is also influenced by the fiber selected for surface layer reinforcement.

When CEM-1 PCB is below the transition temperature. It’s rigid and can mechanically support many components and devices.

When its temperature goes beyond the transition temperature, the epoxy resin becomes viscoelastic. This is because, at this temperature, intermolecular secondary bonds are broken.

The electrical properties for this PCB include electric energy conduction and dissipation and also store electric energy.

What are the Advantages of CEM 1 PCB?

CEM 1 PCB

• It is a cost-effective option for producing PCBs. Only one side of the PCB is coated with copper, which has good conducting characteristics.
• CEM-1 PCB can achieve the same level of mechanical and electrical properties of FR-4 PCB. Therefore it can replace FR-4, which is relatively expensive.
• It can be used to produce PCBs with single layers which are lighter in weight compared to others.
• They are simple and can easily be designed and manufactured.
• Connection of electrical and electronic components like resistors, capacitors, inductors are made on one side of the PCB. This makes the entire production cheap.
• CEM-1 PCBs are ideal for the production of products under a low budget. Also, they are very relevant in bulk manufacturing applications like calculators, radio, printers, remote control, and solid-state drive.

You can produce many devices within a short duration and at a friendly cost.

• It gives a good balance between heats dissipating performance when it is used to manufacture LED lighting.
• This type of PCB has a good physical strength that can give enough support to the components when mounted.
• It has a good glass transition temperature, better heat dissipation, and cab store electric energy.

What are the Applications of CEM 1 PCBs?

There are numerous application where CEM 1 PCBs have been used. For example:

• Computer peripherals used this type of PCB.
• It is used in making simple applications like toys, remote control, calculators, and home appliances. Apart from these, LED lighting can also be made from CEM 1. PCBs. For example, headlights, indicators, and break-lights.
• Computers are very sensitive to heat, and therefore, this makes LED CEM-1 PCBs a much ideal solution. Computer parts like CPU, floppy drive, and power devices are made from these PCBs because they can transfer heat effectively.
• These types of PCBs are used in the production of industrial controls, converters, instrumentation, UPS systems, hard drives, and phone systems.
• They are also used to manufacture automatic dashboards, power supplies, control relays, regulators, power conversions, printers, and power monitors.
• Line reactors, amplifiers, test equipment, and traffic systems also make use of these types of PCBs.
• In addition to these, tools used to perform surgery have also been made from CEM-1 LED PCBs.
• Lastly, even medical scanning technology also uses these types of PCBs to manufacture scanning equipment.

How do CEM 1 compare to FR4?

• Both of them have been made from materials composed of epoxy resin together with woven glass fibers.
• CEM-1 has two layers of woven glass fiber and paper cellulose in-between the layer with epoxy resin reinforcement. On the other hand, FR4 is built of multiple layers of woven glass fiber, paper, and epoxy resin.
• CEM-1 can only produce a single layer PCB. FR4 can be used to build PCBs of single layer PCB, double layer, and other multiple layers PCBs.
• Since FR-4 is capable of producing both single-layer and multi-layer PCBs, It can be a perfect replacement for CEM-1. On the contrary, CEM – 1 can only replace FR- 4 for a single layer and not for multiple layer PCBs. The management and quality control of PCBs is much easier in companies using FR-4 than CEM-1 PCB companies.
• The flexural strength for CEM-1 material is weaker as compared to that of fr-4.
• The thermal expansion coefficient of CEM-1 is greater than that of FR-4. Therefore, the performance of CEM-1material is much better than that of FR-4.
• CEM-1 is much more cost-effective than FR-4. Therefore, when a single-sided PCB is needed, CEM-1 is preferred. It can be used when available instead of FR-4.

What are the Distinct Features of CEM1 Printed Circuit Board?

At time, you may have no option but to choose CEM 1 printed circuit boards. This is mainly due to the unique features of CEM 1 PCB such as:

Single side CEM 1 PCB

• It is a PCB that uses two layers of woven glass fabric, a paper which is cellulose and epoxy resin.
• This material is milky-white or yellow.
• It provides good mechanical properties, thereby possessing good physical strength.
• The CEM-1 possesses excellent electrical properties.
• It is compatible with LED-free reflow technology. This is because it has a transition temperature that is higher than that of FR-4.
• This type of material for producing PCBs also has excellent flexural strength. That is, it can handle physical stress without having to break.
• It can produce only a single layer PCB. Where multi-layer PCB is required, it may not be useful.

single layer vs multi-layer PCB

• Its solder points are not very strong, and this makes it unreliable to some extent.
• CEM-1 is not toxic because it does not have halogen, phosphorus, or antimony.
• It produces PCBs that are very fragile in comparison to other materials. Therefore, its PCBs must be handled with a lot of care to avoid losses.

 What are the disadvantages of CEM1 PCB?

When you choose to use CEM 1 printed circuit boards, it is important to note that you will have to deal with the following:

• This type of PCB lacks good mechanical endurance.
• You can use it to produce single-sided PCB. This is because its laminates are not compatible with through-hole.
• CEM-1 produces very fragile PCBs, which can break easily if not handled with a lot of care.
• Solder points on CEM-1 PCB are not very strong and, therefore, not reliable.
• It can be replaced with FR-4. Incase FR-4 needs a replacement. It is limited since it can only replace the single-layer FR-4 PCB.

Which Software is the Best when designing CEM1 PCB?

There are Computer-aided design systems with special software that helps in laying out the circuit pattern on the board.

The truth is, there are many software in the market today. Of course, they provide a range of functionalities and capabilities.

But, whichever PCB design software you opt for, ensure you the final design in a correct format.

1. Eagle

This means Easily Applicable Graphic Layout Editor. This is the easiest and most commonly used software for designing PCBs.

Cad Soft computer was the initial producer, but currently, Autodesk is its main developer.

The software has a schematic editor that aids in designing circuit diagrams, and it has an extension file called. Sch.

It has different parts and components that are properly defined.LBR extension. The board file extension is .BRD.

2.Multisim

The software is also easy to lean, although very powerful. Workbench initially developed it. Currently, it is a technological development by National Instruments.

This software has microcontroller simulation and import-export features integrated into it.

When students are manufacturing CEM-1 PCB, Multisim software is very relevant for academic purposes.

Also, it can be useful in industries for the new staff induction and internships students in CEM-1 PCB manufacturing industries.

3.Easy EDA

This software is relevant in designing and simulating circuits. It is a tool that is integrated for schematic capturing purposes.

It also serves the purpose of simulating the SPICE circuit, which is based on PCB layout and Ng-spice.

It is an independent software from OS and a web-based, which is used in the browser window. It is also usable in designing CEM-1 PCBs.

4.Altium Designer

The software was developed by an Australian Software Company known as Altium limited.

This software has a schematic capture, PCB design in three dimensions, FPGA development, and management of data.

Altium Designer is the first software to offer 3D visualization.

In addition to this, it is unique because it also does clearance checking of PCB directly from the editor.

5.Ki Cad

Jean Pierre Charras is the developer of this PCB design software. This software is also very extra-ordinary because it can create a Bill of Materials.

It can also do artwork, 3D view of PCB, and all circuit board components.

The software has a library where many components are contained. Those interested in using it have the opportunity to add other custom components.

It is good because it has a limited language burier and therefore many people all over the world can utilize it.

It’s an ideal software for building CEM-1 PCBs because of its uniqueness and the fact that it supports many languages.

6.Circuit Maker

Altium has also developed this PCB design software.

It has a schematic editor which has basic component placement. It is relevant for designing schematics with many channels and hierarchies.

During development, the schematics are uploaded to a server. Anyone interested in the software can access, view, and utilize it.

But you have first to open an account with the software company.

Therefore, if CEM-1 PCB requires multichannel and hierarchical circuits, this software could be the ideal one.

What is the Glass Transition Temperature for CEM-1 PCBs?

Glass Transition temperature (Tg) is the temperature range where CEM-1 PCB materials change from rigid to soft material.

For example, CEM-1 PCB has a Tg of 60/90 °C.

Typical Tg of CEM-1 PCB can sometimes go up to between 110 – 130 °C, but it does not melt.

What is the Coefficient of Thermal Expansion for CEM-1 PCBs?

The CEM-1 PCB coefficient of thermal expansion is the extent to which it can expand when the temperature is increased.

It describes the change in the size of this material triggered by increased temperature.

The idea of measuring the coefficient allows the PCB designer to determine the mechanical compatibility of the CEM-1 substrate.

A CTE greater or less than that of the device connected to the laminate causes fatigue or creep.

CEM-1 undergoes a rapid temperature rise above the glass transition temperature.

When this happens, CTE can limit the maximum temperature that should be used.

The coefficient, thermal expansion for CEM-1 PCBs is 300 Ppm/°K

The CTE can be measured within a range of between 20 to 200°C. This is at a temperature ramp rate of 5°C per minute.

CEM 1 Printed Circuit Board

What is the recommended Thickness for CEM-1 PCBs?

The recommended thickness for CEM 1 PCB is 1.5 mm.

Does standard CEM-1 satisfy UL94-V0 regulations?

Yes, it does.

UL 94-VO is a safety standard that relates to material flammability. It was set up by UL to test the flammability of plastics, although it is currently being used in rubber.

There are several tests within UL94. They include vertical, horizontal, and 45 degrees flame tests, which have been given different classification designations.

When it is subjected to a flame test, it achieves the VO, which is the most difficult one to achieve. Interestingly, this is a requirement for most customers.

CEM-1 satisfies the UL94 regulations, and that is why it is used in producing home appliances, among other products.

This is because products made from CEM are safe. Silicon helps in keeping the flame at bay and prevents the device from burning.

The UL94 regulations aim at testing the following:

• The duration of a CEM 1 PCB can resist fire.
• How the material interior finish surface burns. That is the speed of the flame and the development of the smoke during burning.
• The rating of roof covering flammability.

Why are CEM-1 PCBs Single-layered?

CEM and RF PCB

This is because they are made from materials classified under NEMA. NEMA is a popular material that is known for the production of one-layer circuit boards.

A standard CEM-1 is made up of materials on a cellulose basis.

The materials have a layer of glass fiber laminate, also known as FR-4, on a surface.

It is the only PCB that can be used to assemble devices without realizing the metallization of through holes.

Therefore, CEM-1 is one of the ideal material for producing single-layered PCBs.

How do CEM-1 compare with CEM-3 PCBs?

• They are similar in some ways and different in some characteristics.

Both are impregnated with epoxy resin. Besides, they are made with a paper core in the middle of two fiberglass layers, although the paper used for CEM-1 is different from that used in CEM3.

• Both of these materials are cost-effective.
• CEM-1 is a combination of epoxy, a paper core, and a woven glass fabric surface. On the other hand, CEM-3 is made of plies fabric instead of a piece of woven glass fabric.
• Both are milky white, but CEM-3 is also characterized by smoothness in comparison to CEM-1.
• CEM-3 can perfectly be used as a replacement for FR-4 since they are more or less similar. But CEM 1 is not a recommended replacement for FR-4.
• CEM-1 is used to print circuit boards and has been in use for a long time. On the other hand, CEM 3 is a new substrate material for printing circuit boards. It has been developed based on FR-4 characteristics.
• CEM-1 is easy to punch and can do so even up to 0.093 inches, unlike CEM-3, which doen’t get punched easily.
• CEM-1 also has good electrical and mechanical properties. It also has flexural strength.

On the contrary, CEM-3 is a flame redundant epoxy copper-clad plate glass material.

It is normally used to produce two-sided or multiple layer electronic PCB devices.

• Both CEM-1 and CEM-3 are made from a combination of two or more materials with different chemical and physical properties.

In both cases, synthetic epoxy resin is used to combine the materials, holding them together.

• For these CEMs, it’s the epoxy that aids in transferring the thermal stress between the combined materials. It also helps in protecting the CEM 1 and CEM 3 from both mechanical and environmental destruction.
• CEM-1 and CEM-3 are both lights in weight, although strong and are suitable for making PCBs.

What are some of the Factors to consider when Sourcing for CEM-1 PCB Materials?

There are some factors which influence the sourcing of these materials. For example,

• The availability of PCB materials in the PCB manufacturing company location.
• PCB design required. This should align with board capabilities. CEM-1 is ideal for simple designs that are not meant to last for long since they have low thermal stability.

They tend to lose their lamination easily.

• Width and space of the board determining the amount of current is also another factor to be considered.
• The structural strength of the board is influenced by substrate and laminate.

The materials should be strong enough to hold the PCB together even if it accidentally drops. To select materials for making a PCB, type of board must be considered.

• The material must be able to meet the desired glass transition temperature.
• The laminates used must be able to provide a coefficient of thermal expansion, tension, and shear strength. These properties are present in CEM-1. They have high thermal conductivity.
• Ensure the CEM-1 materials are non-toxic. This is because other materials are toxic, and soldering must be carried out in a closed environment.

Also, fumes must be clean at the time of discharge to the atmosphere.

• The weight of the materials is also a factor to be considered. CEM-1 is light in weight, so this makes it suitable for producing PCBs.
• Ability to handle a high amount of power. CEM-1 material has good resistance to heat.
• Quality of PCB it will produce. The CEM-1 PCB should be able to last longer regardless of whether the device produced is small or big. The CEM-1 should be reliable since consumers and businesses are looking for this in devices that use circuit boards.
• Technical experts who will be able to identify the best CEM-1 materials.

What Factors should one consider when identifying CEM-1 PCB Manufacturer?

As you look for a manufacturer you can trust for you CEM 1 PCB manufacturing needs, you should consider the following:

• A good CEM-1 PCB manufacturer must have a team of experts that provide all the necessary services you may need. For example, they will provide design, manufacturing, and assembly of CEM-1 PCBs.

They also help in identifying the best materials for CEM-1 PCB production.

• They should be in a position to access and utilize CEM-1 materials like glass fibers and epoxy.
• You should be aware of the current market price for the CEM-1 PCBs.

This will enable you to look for manufacturers offering the PCBs at the most economical and genuine market price.

It will help you to avoid overspending, which may reduce company returns.

• Manufacturers most popular in the market are more reliable. They can deliver CEM-1 PCBs that are durable, which can serve for a relatively long period.

The manufacturer should be able to supply well-tested and good quality PCBs.

• They should be able to supply CEM-1 PCBs that are safe and standardized in usage.
• Those who select the right types of PCB materials that can rightly give enough support to the design and application. These are the right manufacturers you should consider.
• The producers who manufacture CEM-1 PCBs which comply with ISO 9001:2015+AS9100D. Also, the products should be made according to ISO 13485, ITAR, STD-001, and IPC standards.
• Lastly, the manufacturers who also produce FR-4 PCBs. This is because if there is a need to replace CEM-1 PCBs, FR-4 can be used.

Once you have all these in mind, you’ll definitely get the right PCB that meet your unique performance requirements.

Which Quality Standards will help you Identify CEM 1 PCB?

Many quality standards safeguard the quality production of CEM 1 PCBs.

These will enable you to get the best that can support the type of application you intend to use.

Therefore, the following quality standards guide us in identifying the best quality CEM-1 PCB:

• It must be manufactured in compliance with ISO 9001:2015+AS9100D.
• The PCB must also be made in compliance with ISO 13485.
• The boards must comply with ITAR standards.
• Compliance with STD-001 and IPC standards is also a must.
• A good quality CEM-1 PCB must be easy to punch.
• It must also pose the best electrical properties.
• A high-quality CEM-1 PCB must have a higher flexural strength. This characteristic makes the PCB the most popular one for single-sided boards.
• The board must be made from substrates and laminates with DK (at 1MHz) 0f 4.2, Tg of 122, and high density.
• It must have good physical strength to support components.
• It must be light in weight.

Additionally, the CEM 1 PCB should conform to the CE, CCC, UL and RoHS standards. Of course, these standards will vary depending on:

1. Geographical location or economic zone
2. Application requirements

How do you design CEM 1 PCB?

For you to design CEM-1 PCB successfully, you have to use computer-aided design systems that have special software.

This software helps in laying out a circuit pattern on the board. This process requires the knowledge of an expert.

PCB Schematics

There is numerous software that include: Allegro designer, Altium Designer, and PCB Droid.

The use of software minimizes errors like skinny traces or incorrect touch. Below are the necessary steps that should be followed when you want to design a CEM-1 PCB.

First of all, you should develop a schematic for the circuit. This is like a roadmap for the components on the board.

The development of the schematic is very important because it illustrates where all the CEM-1PCB components will be placed.

The schematic shows all the symbols representing aspects of switches, resistors, diodes, nodes, among other components.

It is very useful because it can also be used in troubleshooting later on.

You can now decide on the card and template dimension bearing in mind the required circuitry of the CEM-1 PCB.

After this, you can determine the location of the heat sink and other PCB components.

The next step is to decide about the layer stacks. In this case, it is a Single-layer because it’s a CEM-1 PCB. Go ahead and choose both the ground and power planes.

The power plane is a counterpart to the ground plane and helps in providing an AC signal ground.

On the other hand, it provides DC power to the circuits mounted on the PCB.

The tracing of signal interconnections is done on the signal planes which are on the board surface.

Thereafter using dielectric layer thickness, routing copper thickness and width of the trace, determine line impedance.

Place the components considering both thermal and geometry.

Mark the vias and the lands. Rout signal traces using electronically designed tools that create clearance and connections in power and ground planes automatically.

After laying down the design on the schematic, it has to be exported into your industry-standard format Gerber.

This format helps in providing a default language for describing CEM-1 PCB components.

The export generates a file that provides instructions used for the production phase of a CEM-1 PCB.

Therefore, when the Gerber file is ready, you can go ahead and manufacture your CEM-1 PCB.

How are Components mounted on CEM-1 PCBs?

CEM-1 PCB does not support the through-hole technique of mounting components on the board. It works with surface mount technology.

The components have been made with small metal tabs that are soldered directly onto the PCB surface.

With the current technological development, the components have become even much smaller in size.

For example, they are between ¼ to 1/10 the size and weight of through-hole components.

To mount components on the board, first of all, you have to coat the PCB with copper, which is a good conductor of heat.

Secondly, apply a layer of solder mask so that you can protect the CEM-1 PCB from oxidizing.

Thereafter, using a silkscreen, mark out all the positions of the components on the board.

The next step is whereby you solder the components like resistors, diodes, nodes, capacitors, and inductors, among others on the board.

After soldering all the components, the CEM-1 PCB is now ready and can be used to produce applications like calculators.

Mounting components on CEM 1 PCB

What are the Steps in Manufacturing CEM-1 PCBs?

PCB ignites life into the electronic devices.

They are the backbone of all electronics ranging from the simplest like clocks to the most sophisticated ones.

A PCB provides both electric and mechanical satisfaction to the electronic devices.

Below are the various steps involved in manufacturing CEM-1 PCBs.

Step 1- Design and Output

It’s recommended that the manufacturers should familiarize themselves with the design before embarking on the process of manufacturing the PCB.

This helps in avoiding errors that may be made during manufacturing.

The manufacturer should approve the design of their choice, and the designer can now go ahead and export it.

This is done in a format that is supported by the manufacturer, most likely extended Gerber.

The Gerber file encodes crucial information, which includes copper tracking layer, component notations, among others.

At this point, all CEM-1 PCB components get checked thoroughly, and any mistake identified and gets corrected here.

The designer, at this point, looks at the plan to confirm the width, board edge spacing, and trace.

Step 2: Transfer File to Film

This is the printing of the PCB. It is done after generating the Gerber file and running the DFM check to ensure there are no errors.

A plotter, a special printer, is used to make photo films of the CEM-1 PCBs. That is, the films are used to mark highly detailed images of the design on the CEM-1 PCB.

A plastic sheet containing a photo negative of PCB is developed. There is a clear part for copper and black representing the area that will be etched away.

Step 3- Printing the Image on the Surface.

This is the actual preparation of the CEM-1 PCB. The CEM-1 PCB comprises the laminated board made from epoxy resin, paper, and glass fiber, which is the substrate.

The substrate is the sturdy and dust resistant PCB starting point. The copper is pre-bonded on one side of the board because it is a single-sided board.

The image printing process involves whittling away of copper so that the design from the film can be seen.

Cleanliness must be observed at this stage so that no dust particles settle on the laminate to prevent short circuits.

The clean board then receives a photo of reactive chemicals, which becomes hard after being exposed to ultraviolet rays.

These photos are called photoresist. They help in resisting the extra match of the same photos from the film.

The photoresist areas are passed through UV light so that it can become hard.

The black ink that comes from the plotter prevents the UV light from reaching the areas that are not meant to harden. These areas are later removed.

When the board is prepared, it is washed using an alkaline solution to remove any photoresist left unhardened.

Anything left on the board surface is pressure washed, and the CEM-1 PCB is dried.

The board emerges with resist properly covering the copper area. A technician should now examine it to make sure there are no errors that have occurred.

Step 4: Removing the Unnecessary Copper

The excess or exposed copper has washed away with a more powerful chemical solution. The desired ones remain protected under the hardened layer of photoresist.

Once this is done, it is again washed using another solvent that accomplishes the task of washing. This leaves the CEM-1 PCB glittering with only copper substrate crucial for PCB.

Step 5: Layer Alignment and Optical Inspection.

CEM-1 PCB is a single layer and therefore does not need to go through layer alignment.

Instead, the technician can just pass it through an optical inspection machine to ensure there are no errors.

A laser sensor is used to scan the layer and compares the digital image with the original Gerber file.

Should the laser sensor discover any inconsistency, the information is displayed on the monitor, and the technician examines it.

Upon passing the inspection, it is then moved to the final production of a CEM-1 PCB.

Step 6: Layer up and Bonding

Here the board takes shape by fusing the layer and the substrate. This takes place in two steps; layer up and bonding.

The CEM-1 layer materials include a sheet of glass fiber which has been pre-impregnated with epoxy resin. A thin copper also forms the bottom and top covering of the original substrate containing copper trace etchings.

The substrate and the layer are sandwiched on a heavy steel table. This is done using a metal clamp and thereafter pressed to stick together using a bonding press computer.

The computer helps to orchestrate the process of heating the stack. It also shows when to apply pressure and when to allow the stack to cool at a controlled rate.

Step 7: Final Etching

Tin is used to protect the desired copper during this stage. All the unwanted copper is removed using a chemical solution.

This results in the proper establishment of conducting areas and connections.

Step 8-Application of Solder Mask

Cleaning and covering of the board are done using an epoxy solder mask ink. A blast of UV light is subjected to the board and passed through a solder mask photo film.

All the parts covered remain unhardened and later removed.

Finally, the CEM-1 PCB is cured by passing it through an oven.

Step 9: Surface Finish

The boards are subjected to hot-air leveling, which helps in producing uniform boards that result in a good finish.

Step 10: Silkscreen

At this stage, the CEM-1 PCB is almost complete because here is where it is printed using inkjet. The writing information it receives at this point contains all the important information about the PCB. The board then goes through the final stage of the coating and curing stage.

Step 11: Testing the CEM-1 PCB Electronically

It is recommended that the company technician should run an electrical test on the CEM-1 PCB. This is done using flying probe testing that tests the performance of each net on a bare printed circuit board.

This test is automated, and it confirms if the PCB is functioning. It also confirms if it conforms to the initial design on the Gerber file.

Is CEM-1 PCB the same as CEM-3 PCB?

No. They are not the same.

They have different characteristics.

CEM 3 PCB

• CEM-1 materials consist of paper and two layers of woven glass fiber, paper, and epoxy or phenol compounds.
• On the other hand, CEM-3 material consists of white color plies of glass fiber and epoxy resin compounds.
• CEM-1 material is used to produce single-sided PCB only, whereas CEM-3 materials are used to produce double layer PCB also.
• CEM-1 can be used instead of FR4, but unfortunately, it is costly as compared to FR. Contrary to this, CEM-3 is a perfect replacement for FR4 since it’s relatively cheaper than FR4.
• Lastly, CEM-1 has a higher mechanical strength as compared to CEM-3 and FR4. CEM-3 mechanical strength is even lower than that of FR4.

What is the Dielectric Constant for FR1 PCBs?

The dielectric constant for FR1 PCB is the ratio of its permittivity to free space. This is also known as relative permittivity.

It is the measure of this PCB material’s ability to store an electric field in the polarization of the medium.

This is measured in farad per meter (f/m). The dielectric constant for FR1 PCB is C-96/20/65 C-96/20/65+D-24/23.

Can CEM-1 support High Wattage components?

Yes, it can, because it has been made from epoxy resin and fiberglass. These two materials are the determinant for its durability, even in high voltage situations.

CEM-1 will support high wattage components because it possesses the best dielectric properties.

What is the Peel Strength for CEM-1 PCBs?

CEM-1 PCB is built by combining two layers of fiberglass, a paper, and epoxy resin. These materials need to be stacked together to form a single layer, which is CEM-1 PCB.

The combining force, the epoxy resin, must possess a very strong adhesive characteristic to support the combination of these materials.

The adhesive strength of CEM-1 PCB materials is what is called peel strength.

It’s important because it will hold the materials together and facilitate the manufacturing of PCB and applications using the technology.

The peel strength for CEM-1 PCB is in two categories, namely:

1. All copper profile foils are greater than 17µm or [0.669 mils] regardless of whether it is low or very low profile copper foil.
2. The standard profile copper foil

1. After thermal stress
2. When subjected to a temperature of 125 ^oC
3. After the process solution, all other foils are composite.

What is the Flexural Strength for CEM-1 PCBs?

Flexural strength of PCB

Flexural strength is the ability of a CEM-1 PCB material to withstand a bend without having to break.

This PCB can cope with stress or modulus rupture. It is the highest stress CEM-1 PCB can experience before it can yield to rupture.

The flexural strength of CEM-1 PCB is in two categories. It is presented either in length or cross.

The flexural strength in length is 52 PSI x 10^3, while the cross flexural strength is 39 PSI x 10^3.

What are the Rates of Moisture Absorption in CEM-1 PCBs?

CEM-1 PCBs are hydrophilic since they have been made from paper. They absorb moisture when exposed to the humid environment.

However, the rate of water absorption is as low as 0.17 percent.

What are the Properties of Epoxy used in CEM-1 PCB?

There are many properties of epoxy resin used in CEM-1 PCB. These properties include the following:

• It is resistant to flame.
• The material is hydrophilic and therefore absorbs moisture during CEM-1 PCB formation. This results in swelling of the substrate. When swelling occurs, there is a dimensional change, which in turn creates localized stresses.
• It is a good heat conductor and, at the same time, resistant to heat.
• Epoxy resin makes the board strong and rigid since it has good mechanical and physical strength.
• It belongs to the family of monomeric or oligomeric materials used in the formation of CEM-1 PCBs.
• It has excellent resistance to chemicals.
• Epoxy resin also has a low curing contraction.
• Lastly, it has very good adhesive strength. This promotes sticking together of the CEM-1 PCB materials.

What is the Highest Number of Layers for CEM-1 PCBs?

 PCB Layers

CEM-1 PCBs have only one layer because it has only one side of PCB.

The material used in NEMA specification classification is normally known for the production of one layer printed circuit boards.

The standard CEM-1 material is a composite material on a cellulose basis. It is composed of two layers of glass fiber laminate (FR-4) on the board surface.

These two layers are sandwiched with paper cellulose and impregnated with epoxy resin to form one layer PCB.

Therefore, CEM-1 PCB can only contain one layer.

What is the Recommended Copper Thickness for CEM1 PCB?

There is the standard copper-clad laminate thickness (CCL) for a CEM-1 PCB, which should be at least 0.5mm.

However, there is much thinner CCL CEM-1 CPB, which could be as thin as less than 0.5mm.

The recommended standard thickness is many. It can be 0.5mm/0.8mm/1.0mm/1.2mm/1.6mm/ 2.0mm/2.4mm and 3.2mm.

There could also be other copper thicknesses but beyond 3.2mm but must only be produced when requested for.

What is the Drill Diameter for CEM1 PCB?

The drill diameter of CEM-1 PCB is very small. It is #6 or 3mm. If the board thickness is 1.6mm, drilling a hole of 3mm will be possible without causing any damage to CEM-1 PCB.

The diameter drilling can be done very successfully using an HS steel bit. But since CEM-1 PCB is made from fiberglass, many holes may not be drilled.

This is because fiberglass wrecks tools rendering the drilling bit blunt.

Therefore, if you want to drill many 3mm holes on CEM-1 PCB, it is advisable to use carbide tools.

This can withstand the fiberglass material that makes the CEM-1 PCB. It also can drill holes of 3mm in size, which is recommended for this type of PCBs

What are the Distinctive Colors of CEM-1 PCBs?

The color of this type of PCB is two separate ones. It could be milky white or sometimes milky yellow.

Which Reinforcement Material is used in CEM1 PCBs?

The materials used in the reinforcement of CEM-1 PCB are always the backbone of the laminate structure.

For the laminate to be considered a viable interconnection structure, reinforcement provides the necessary strength and dimensional stability.

Reinforcement helps in improving the electrical properties of the laminates. It should be selected with a lot of care because it can influence manufacturing problems.

The reinforcement material used in CEM-1 PCB is a woven glass fabric. It is the most commonly used in rigid laminates.

This is because it has good electrical properties, perfect dimensional stability, and highly chemical resistant.

The reinforcement material also has a low water absorption rate; its tensile strength is high and has good heat resistance.

This woven glass fabric is formed when it is molten into filaments of 3.5 µm-20 µm diameter. They are then spun into around 50-800 filaments strands.

These strands are twisted and woven into fabrics.

Thereafter, an organic surface finish is applied to the glass fabric to act as a coupling agent. This helps in aiding the bond to the impregnated resin.

Which Resin is used in the Manufacture of CEM-1 PCBs?

There are two types of resins used in manufacturing CEM-1 PCB. These are phenol-paper and epoxy resin laminate.

They have been classified under the generic NEMA descriptions.

Resins are the most basic board materials, and they are very important because they bind the PCB materials together.

The chemical effect, environmental performance, electrical, and mechanical properties are all influenced by choice of the resin binders.

For specialist applications, there has been an introduction of other materials and mixtures of materials.

Epoxy resin is a very common and most preferred material because it has good mechanical and electric properties. It is not expensive, and can easily be dissolved in safe and less expensive solvents.

In addition to these, it can easily be used for impregnating because it adheres well to the copper foil.

Lastly, it facilitates the perfect bond between copper and glass fiber, which is finished with epoxy saline.

What are some of the Examples of CEM-1 PCBs?

There are several CEM-1 PCBs.

You can these PCBs in air conditioning and ventilation systems, Audible signaling devices, Audio amplifiers, buttery charger, circuitry protection, and converters.

Others are for drive motors, electronic ballasts, electronic filters, diode testers, digital meters, electromechanical controls, and heat sinks, among others.

 CEM 1 PCB

How do prices of CEM1 PCB and that of FR4 PCB compare?

FR-4 is a perfect replacement for CEM-1 PCB, but the only problem is the difference in their cost.

CEM-1 PCB materials are very cheap in comparison to FR4 materials. The manufacturing of the cost of CEM-1 is, therefore, lower than that of FR-4.

Since CEM-1 PCB is also a single layer PCB, it is cost-effective than FR-4, which also includes multi-layer PCBs.

Where a single layer PCB is required, it would be wise to choose a CEM-1 PCB over FR-4 PCB.

What are CEM1 PCBs Punching Properties?

The punching properties of this PCB are those characteristics that allow it to be punched. Below are the punching properties of CEM-1 PCB:

• They are easy to punch because it is made from paper.
• It is rigid and, therefore, can be punched well up to 0.093 inches.
• It has good mechanical and physical strength and, therefore, can bear punching.

Why are CEM1 Materials Impregnated with Epoxy Resin?

CEM-1 materials become impregnated with epoxy resin for various reasons. They help to strengthen the fiberglass.

They also aid in making the CEM-1 materials adhesive so that they can stick together.

The use of epoxy resin in building CEM-1 PCB enables them to have good mechanical and electrical properties.

Epoxy resins are also used in this case because they are cost-effective. They can also dissolve very easily in solvents that are not expensive.

They can be formulated to become flame retardant.

Why is CEM-3 more compatible with Through-hole Plating compared to CEM-1?

CEM-3 is somewhat similar to CEM-1 in that it has been impregnated with epoxy resin, just like CEM-I. It also has woven glass fabric on the surface like CEM-1.

However, its core is made up of unwoven matte fiberglass.

On the other hand, CEM-1 has been built with woven glass fiber at its core.

These unwoven fiberglasses that have been used to build CEM-3 make it more compatible with through-hole plating than CEM-1.

What makes CEM-1 PCBs have better Physical and Mechanical Properties compared to FR2 and FR-3 PCBs?

CEM-1 PCB has good physical strength and mechanical properties than FR-2 and FR-3 PCBs.

This is because it is made from paper and glass fiber, which helps in making it strong and stiff.

The fact that it is also impregnated with epoxy resins improves both its physical strength and mechanical properties.

Why is CEM-1 PCB not suitable for Plated Through the hole?

CEM – 1 PCB is classified by NEMA. It is made from paper, two layers of woven epoxy resin, and phenol compounds.

It is used in producing only one-sided PCBs. It is not suitable for plated through-hole because laminates are not compatible with metallization in holes.

Also, the CEM-1 PCB is built with woven fiberglass, and this makes it incompatible with plated through-hole.

What is CEM-1 LED PCB?

 CEM 1 LED PCB

The LED lighting in the current market is produced by manufacturers who use CEM-1 PCB as their base materials.

This type of PCB offers a good balance between heat dissipation and the entire PCB cost.

The PCB is used to manufacture LED lighting, which is currently many in the market in different shapes and colors.

These kinds of PCBs generate a lot of heat than doesn’t cool easily. They transfer and dissipate heat much efficiently. Examples of CEM-1 LED PCB applications to include:

• Automotive headlights.
• Landing lights at the airport runway.
• The lighting from solar.
• Flashlight and lanterns.
• The traffic and signal lighting.
• Hospital operating room lighting.
• High grow to light for plants.

Why is CEM-1 PCB preferred in the Manufacture of LED PCBs?

It is preferred because this type of PCB offers the best heat dissipation at a relatively cheaper cost.

They are mostly used to produce PCBs used in telecommunication industry because it has improved heat transferability.

Apart from this, they are preferred because they are more durable and lighter in weight. This makes them desirable in this industry applications.

They are also applicable in automobile LED PCB, where they are used to make head-lights, indicators, and break-lights.

Computers are very sensitive to heat, and therefore, this makes LED PCBs much ideal solution. Computer parts like CPU, floppy drive, and power device are made LED PCBs because they can handle and transfer heat.

Lastly, tools used to perform surgery have also been made from CEM-1 LED PCBs. Even medical scanning technology also uses these types of PCBs.

What is Rigid CEM-1 PCB?

Rigid CEM 1 PCB is made from composite material on a cellulose basis, which has one layer of glass-fiber laminate.

Two layers of woven glass fabric are combined with paper cellulose. It is then impregnated with epoxy resin, which makes it rigid and strong.

These are PCBs that have good physical resistance. It has marked PCB components that can easily be repaired and maintained.

This type of PCB has well-organized signal paths. It is cost-effective because it does not contain expensive connectors.

It is referred to as rigid because it holds good dimensional stability.

What are the Heat Dissipation Properties of CEM-1 PCBs?

There are many heat dissipation properties of this type of PCB. These properties include:

• Good thermal properties and therefore conducts and transfers heat perfectly.
• It is rigid or hard and strong.
• The CEM-1 PCBs have a very high glass transition temperature.

Is CEM-1 PCB Shock Resistant?

Yes, it is. This is because it is has been impregnated with epoxy resin, which is resistant to moisture, high temperature, and thermal shock.

How does CEM-1 PCB Improve its Tensile Strength?

This is also called slippage or rupture strength of a CEM-1 PCB. It is the amount of force that is required to pull this type of PCB.

This is the strength this PCB can bear without having to deform permanently.

The maximum load it can support without breaking divided by the initial cross-sectional area of the material is tensile strength.

The tensile strength of CEM-1 PCB can be improved when it is saturated with moisture, and the temperature is increased.

This begins from a temperature of 75 degrees Celsius up to 105 degrees Celsius.

To improve the tensile strength, you have to use more epoxy resin to impregnate fiberglass and paper cellulose materials.

In addition to these, more cross-linking can be added to the CEM-1 PCB materials during the production process.

In what Circumstances is FR3 replaced with CEM-1?

• FR3 cannot build multi-layer PCB, and therefore it can be used to build only a single layer PCB. Because of this, it can replace CEM-1.
• FR3 can replace CEM-1 when a cheaper PCB material is required. Also, it can be a perfect replacement for CEM-1 when a simple technology is involved in building the PCB. In addition to these, it could be used instead of CEM-1 when FR4 is not available or expensive.
• FR-1 and FR-1 materials are also used to manufacture single layer PCBs. In situations where they are not available to replace CEM-1, FR-3 could be used.

Can CEM-1 PCB prevent Water Absorption?

No, it cannot prevent water absorption.

When CEM-1 absorbs water, its appearance in terms of size changes. It displays a swelling coefficient when it’s saturated by moisture.

It brings out two characteristics: The swelling percentage and the percentage of moisture content in CEM 1.

For example, CEM1 exposed to moisture could have a swelling width and length of 2%.

It will also have a thickness of 4%, moisture content of 3.8 %. Lastly, it will have a swelling coefficient of 0.05 in-plane and 1.5 out of the plane.

Apart from CEM 1, what other PCB Materials are used in the Industry?

There are quite many PCB materials being used by industries.

The most crucial element is a dielectric substrate, which could either be rigid or flexible. They are used together with conducting materials like copper on the surface of the board.

The materials used include dielectric material and epoxy laminate, which are highlighted below.

·FR4 –Fire Retardant 4

This is the most commonly used glass laminated material. It is preferred because it has a wonderful mechanical strength.

It is one of the cheapest PCB materials with a standard glass transition temperature of 130 degrees Celsius.

FR4 is compatible with lead-free reflow technology, and it is also halogen-free.

·FR-1 and FR-2

This is also a PCB material made from paper and phenol compounds. It can only be used to produce a single layer PCB. The two possess the same characteristics.

However, there is a slight difference in the glass transition temperature.

FR-2 has a lower glass transition temperature in comparison to FR1, which is relatively higher. These two PCB materials are also categorized into halogen-free and non-hydrophobic.

·CEM-3

This belongs to the Composite Epoxy Material family of PCB materials. It is white in color and glass epoxy popularly used to produce two-layer PCBs.

Unfortunately, it has a lower mechanical strength compared to FR4.

This PCB material is cheaper than FR 4, and therefore it can be used instead of FR4.

·Polyimide

This type of material is used to make flexible PCBs. It is made from Kapton, Rogers, and DuPont. The PCB material has very excellent electrical properties.

It also has felicity, a huge temperature range, and highly resistant to chemicals. This material has a working temperature of between 200 to 300 degrees Celsius.

·Pre-impregnated

This is fiberglass impregnated with pre-dried resin. The resin is dried so that when it is heated, it flows, sticks, and immerse completely.

It has an adhesive layer, which helps in giving it a strength, which is similar to that of FR4. This material has numerous versions that are influenced by the resin content, thickness, structure of the layer, and impedance.

The material possesses a high glass transition temperature and is also free from halogen.

With this information, you should be able to choose and analyze CEM 1 PCB.

Besides, you can choose high quality and reliable CEM 1 printed circuit board.

For inquiries or more personalized information on CEM 1 PCB, contact us now.