Top things you need to know about the Rigid-Flex PCB Manufacturing Process!

By | Date posted: | Last updated: February 15, 2023
Rigid Flex PCB Manufacturing Process

Rigid-flex PCBs are extremely popular as they combine the characteristics of rigid as well as flexible PCBs. Essentially, they layer flexible circuit substrates inside rigid circuit board materials. What it offers, therefore, is the stability and strength of rigid PCBs along with the versatility of flexible circuits. The combination of rigid-flex PCB manufacturing opens a wide range of possibilities when it comes to complex and challenging designs. What it also offers is improved service reliability and performance.

Rigid-Flex circuit boards find wide use in commercial and industrial applications including but not limited to:

  • Military
  • Aerospace
  • Digital Cameras
  • Cell Phones
  • Pacemakers
  • Barcode scanners and more

Advantages of Rigid-Flex PCBs

Some of the specific advantages that rigid-flex PCBs offer include:

  • Stability – With their structure comprising of interchanging layers of rigid and flexible PCBs they offer mechanical stability. They also lend themselves to easy installation in small spaces.
  • Reliability of connections – Rigid-flex PCBs offer increased stability as well as polarity. This leads to reliable connections.
  • Cost effectiveness – Rigid-flex PCBs are extremely cost-effective and ensure that your project is viable.
  • High-density applications – With miniaturization and high-density applications growing in popularity so is the use of rigid-flex PCBs.
  • High shock and vibration resistance – Rigid flex PCBs are resistant to shock and vibration and find a place in a wide variety of applications.

Rigid-Flex PCB Design Guidelines

While the advantages of rigid-flex PCBs are well-documented, there are several design guidelines that need to be followed when it comes to manufacturing these PCBs. These include:

1. Determine The Number of Layers

Rigid-flex PCBs are made of alternating layers of flexible and rigid PCB Material. It is therefore important to figure out the exact layer count that is required. It is prudent to consult your electronics contract manufacturer early to ensure that all the requirements can be met.

2. Heat Sinking

Due importance needs to be given to having a heat dissipation mechanism in place. In the absence of it, the device performance can be impacted, and it may also result in damage to the device. The PCB needs to facilitate heat sinking.

3. Material Layup

Layup of materials is yet another crucial factor. This includes checking for:

  • The UL flammability rating
  • Minimum bend radii needed
  • RoHS certification
  • Impedance control
  • Mechanical considerations, and more.

Material layup, in turn, impacts both cost as well as manufacturability.

Steps Involved in Rigid-Flex PCB Manufacturing Process

The rigid-flex PCB manufacturing process involves the following steps:

Base Preparation

This involves preparation of the laminate. The laminate, in turn, features a copper layer. If the copper contains anti-tarnish, it needs to be removed by immersing it in acid solution.

Circuit Patterns / Structure

Through a process of either photo imaging or screen printing, circuit patterns are generated.

Circuit Pattern Etching

Etching the circuit pattern is largely done by spraying a solution over the circuit pattern or dipping the laminate in an etching solution. Etching is then undertaken on both sides of the circuit pattern.

Drilling Holes

Holes are next drilled using lasers. Laser drilling, in turn, assures precision as well as minimizes waste.

Through-hole Plating

Copper is deposited into the drilled holes and plated with a chemical. This step is crucial to create electrical interconnections.

Coating Etch-Resist and stripping

This step involves applying a photosensitive etch-resist coating on the substrate. The chemical resist applied to the plated through-hole is next stripped.

Cover lay Application

A cover lay is applied to the PCB to protect it from harsh environmental conditions. The coverlay material is screen printed onto the surface of the circuit board and exposed to UV.

Cutting the Flex

The individual flex board is now cut from the production panel with extreme caution and precision.

Lamination

In this step, the flexible printed circuit boards is laminated between the rigid sections.

Electrical Testing and Verification

Electrical testing and verification are the final step that ensures circuit performance and quality.

With the above steps you can rest assured that you will get a performance-driven rigid-flex PCB. The important bit is to choose a contract manufacturer that specializes in the fabrication of rigid-flex PCBs, who can understand your bespoke requirements and deliver accordingly.

As a leading rigid-flex PCB manufacturer, we are fully equipped to handle your PCB manufacturing requirements. With over 4 decades of experience in rigid-flex PCB manufacturing as well as assembling PCBs with differing levels of complexities, our team of experts & state-of-the-art equipment ensures that all our PCBs meet the industry standards of quality.

In case if you have any questions or queries regarding our rigid-flex PCB manufacturing services, please feel free to contact us via email at [email protected] or call us at 714/630-9200.

Everything you Need to Know About PCB V-Scoring!

By | Date posted: | Last updated: January 6, 2022
PCB V-Scoring

PCB V-scoring is a form of PCB panelization that allows you to both fit multiple PCBs onto a single manufactured board and allows you to separate the boards after assembly. It derives its name from the fact that it involves cutting a “V” shaped groove at the top and bottom of the PCB.

In order to V-score a PCB, what is required is a specialized scoring tool with a top and bottom blade.

The Requirement for PCB V-scoring

V-scoring is required to make the printed circuit board assembly process efficient. The process of V-scoring ensures that the assembled boards can be separated using minimal pressure.

Importantly, V-scoring helps with the following:

  • Making efficient use of the board space.
  • Reducing manufacturing cost by making several PCBs on one board. It also helps with putting two or more related circuits on the same assembly that aids in efficient sub-assembly. Depaneling machines are also relatively inexpensive. Besides, they are portable and not high on maintenance.
  • Saves time as you can easily separate parts from a completed assembly. The process of V-scoring allows you to put components on each section of the board in a single run. Later you can simply separate the boards making the PCB assembly process both cost as well as time-efficient.

Challenges of PCB V-Scoring

  • V- scoring is restrictive in terms of panel design. V-groove isn’t the best option for designs where the components are too close to the edge.
  • It also necessitates a clearance of 0.05 inches between the components and V-grooves. Tall components, particularly, must be placed away so that the cutter doesn’t come in their way. Similarly, components with large connection areas should also be placed away from the groove.
  • V-grooves can impact the structural integrity of the PCB leading to warpage or being caught in the wave-solder machine. Adding jump scoring to the leading and trailing edges of the array, help to strengthen it.

How do you specify PCB V-Scoring?

The PCB V-score can be specified based on the depth of the score or looking at the cross-section.

The standard way to specify the V-score is to cut 1/3rd on top, 1/3rd at the bottom, leaving 1/3rd of the web in the middle. Manufacturers are known to offer a 90 degree and 30 degree score as well. While the ninety-degree score is known to break easier than a 30-degree score, it takes more space on the layout.

General Rules for PCB V-Scoring

The general rules of the thumb for effective PCB V-scoring are as below:

  • The spacing between the boards should be 0 mm.
  • The minimum PCB footprint size for V-scoring is 75mm x 75mm, and the maximum size is 450mm x 1245mm.
  • V-scoring should go straight across the whole board, although floating vertical and horizontal lines are also possible.
  • Spacing between the V-scoring line and the outline of the PCB should be at least 0.35mm.
  • The board thickness of a V-scored board should be at least 0.6mm.

PCB V-SCORE VS. TAB ROUTING PCB PANELS

The choice of V-scoring versus tab routing largely depends on the PCB design. The following factors would come in handy in making the right choice:

  • Shape of the board – V-scoring works well for square or rectangular boards while tab routing lends itself to unusual shapes.
  • Edge components – For edge-hanging components, tab-routing is a far more workable option.
  • Edge Quality – V-scoring results in rough edges. If edge quality is of importance, once again tab-routing will be preferable.
  • Time – Tab routing takes more time and labor to set up. V-scoring, on the other hand, is far quicker.
  • Waste material – V-scoring tends to waste far less material than tab-routing and is therefore more cost effective.

To Sum Up

PCB V-scoring is a major source of cost advantage to electronics manufacturers. It takes away the need for the space needed for routing and therefore offers the ability to add an increased number of rows to the fabrication panel. Wasted laminate is thereby eliminated. Not only does V-scoring save money but also time, as it streamlines the fabrication and processing method.

Technotronix is one of the leading PCB manufacturers in the USA. We have over 4 decades of experience in providing innovative PCB manufacturing services using modern technologies & the latest machinery. We are adhering to strict high-quality standards and compliant with the RoHS (Restrictions of Hazardous Substance) directives. We can fulfil the varied needs of our customers from the simple board to the most complex board for PCB prototype to production. For more information, contact us via email at [email protected] or call us on 714/630-9200.

Leaded Solder vs Lead Free: The biggest debate in PCB manufacturing!

By | Date posted: | Last updated: February 15, 2023
Leaded Solder vs Lead Free

You sure want to stay compliant with RoHS guidelines that restrict the use of hazardous substances in electrical and electronic equipment, lead being one. PCB Manufacturing, however, has been debating the merits of using leaded versus lead free solder for a long time. Let us look at the relative merits of both in detail:

What Are Lead Solders & Lead-free Solders Made of??

Lead solder also referred to as SNPB solder essentially comprises of lead and tin as its base components. Increasingly, the occupational risks of soldering with lead have been highlighted. Essentially, the dust and fumes generated by lead soldering have been found to be toxic when inhaled. Lead based solder is thus a documented health hazard. In 2006, the Restriction of Hazardous Substances Directive (RoHS) was adopted by the European Union (EU).

Lead-free solder has emerged as a replacement of the conventional lead solder. Lead-free solder contains the following substances in varying proportions:

  • Copper
  • Tin
  • Silver
  • Nickel
  • Zinc
  • Bismuth
  • Antimony

Some of the commonly used lead free solders include:

1. Tin-Silver
In such solders, the silver acts as a catalyst as also increases the electrical conductivity of the joint. Tin in this case acts as the base metal which offers strength to the solder. It also acts as a protective agent and reduces the possibility of corrosion.

2. Tin-Copper
The role of copper in the solder is to improve mechanical strength as also the electrical conductivity.

3. Tin-Zinc
The use of zinc goes a long way in lowering the melting point of the solder.

Leaded Solder Vs Lead-free Solder Paste

There are several advantages of using lead solder when compared to lead-free solder.

Advantages of using Lead Solder

Strong joint formation
Lead solder typically offers good electrical conductivity between various metals leading to strong joints.

Ease of use
The advantage with leaded solder is that there is no need for any cleaning agents before its application. The solder paste can be applied directly onto the surface. On heating the molten solder flows into the gaps and once it solidifies it forms a strong bond.

Strong Wetting Property
Since lead solder has a strong wetting property, it is easy for it to flow in narrow spaces.

Disadvantage of Using Lead Solder

The disadvantages of using lead solder includes:

Toxicity
On heating, lead solder produces poisonous gases that can pose a serious threat to life.

Heat dissipation
Lead solder is known for its high thermal resistance. This means heat dissipation is an issue.

Flammability
Given the flammability of lead solder, there is high risk of fire.

Cost
Depending upon the purity level of the solder, the cost of lead solder is also high.

Advantages of using Lead-Free Solder

The advantages of using lead-free solder include:

Low cost
Lead-free solder costs lower than leaded solder and is therefore far more affordable.

Environment friendly
The big advantage with lead-free solder is that is does not produce toxic fumes or waste material and therefore does not contaminate the environment.

Safety
With lead free solder being less combustible, the chances of fire are low.

While lead-free solder joints tend to look different in appearance, joints soldered with lead-free solder paste tend to be reliable. Of course, in order to eliminate soldering defects you need to look at many other factors including but not limited to the temperature, vibration, pre-heating time and throughput and the skill level of the operator. The PCB fabricator’s experience in RoHS material compliance can go a long way in ensuring reliability.

The design layout of the circuit board, and the right component selection also have strong roles to play when it comes to quality control issues. Additionally, the choice of lead-free products needs to be made as per the design parameters. Proper board layout and component selection will ensure that there is no damage to electronic components. This is particularly important as during reflow high temperatures are experienced for extended time periods.

To sum up

Reliability of the final product demands that the solder joints are reliable and that they do not act as a heat intermediary. When making the decision of what kind of solder will work best for your PCB manufacturing project, it is important to consider factors such as:

  • Safety
  • Cost
  • Wiring Requirements
  • Ease of handling, and more.

With a reliable PCB manufacturer you can rest assured that all RoHS material compliance issues are taken care of without sacrificing quality or time to market.

Technotronix is one of the leading providers of Lead-Free PCB manufacturing services to all the dominant industries. Our main strength lies in the extensive experience and skilled team of experts to build Lead-Free and RoHS Compliant PCB Assembly and manufacturing solution. You can drop an email to [email protected] or give us a call at 714/630-9200 to solve your queries or to get a quote.

Common mistakes to avoid in PCB layout design for manufacturability!

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

PCB is a crucial component that ensures the functionality of any electronic device. Therefore, optimizing the PCB layout design with the utmost care is essential, as even minor design errors can compromise PCB integrity. Such errors can lead to manufacturing delays and increased costs.

Fortunately, numerous design tools are available to help PCB board manufacturer minimize design-for-assembly errors and reduce costs. By leveraging professional PCB layout services, you can ensure that your design is efficient and manufacturable, avoiding common pitfalls and optimizing overall production.

Here are 7 common PCB layout design mistakes that need to be avoided to ensure that the PCB functions reliably.

#1. Trace Geometry

PCB traces transmit electrical signals between different components of the circuit. The geometry of each trace, therefore, is extremely important. It is important that the width and thickness of each trace be carefully maintained.

It will help to consider facts such as the traces placed on the external layers of the PCB, can carry a higher current at the same thickness as they can take advantage of the heat dissipation. The trace width also depends upon the amount of copper used for that layer. Other than the width, the thickness of each trace also needs to be considered. Several PCB designers often choose a standard thickness value; however, you need to make sure that the thickness value is sufficient for high power tracks. Greater thickness also means a lower resistance to passage of current.

#2. PCB Layout

The importance of an effective PCB layout cannot be overstated. With the trend toward miniaturization, smaller components and reduced distances between them are becoming more common. An inefficient layout can lead to numerous non-compliance issues, particularly when dealing with components that have smaller pitches and higher pin counts.

Choosing a PCB layout design that meets the circuit’s needs is crucial. It’s important to allocate sufficient space on the PCB to accommodate any additional components that may be required. If these components are not used, corrective measures can be taken before PCB manufacturing begins, ensuring a smoother production process and higher overall quality.

#3. Decoupling Capacitors

Decoupling Capacitors have a strong role to play in ensuring that stable power supply is made available to all board components. These capacitors need to be connected in parallel with the power supply. It is also important to ensure that they be placed as close as possible to the pins of the components that need power. The power line also needs to be properly routed to ensure that the decoupling function works well.

#4 Automatic Routing

While many designers tend to take advantage of the automatic routing functionality that is offered by design tools, it is important to remember that automatic routing occupies a large area of the PCB. Besides, it also creates via holes that are larger than what you tend to create with manual routing.

#5. Electromagnetic interference (EMI)

Improper PCB design also often leads to electromagnetic interference. To avoid this, it is important to group elements as per their functionality. For example, there can be different analog and digital blocks, low speed, and high-speed circuits, and more. Additionally, it is important to eliminate right angles on the traces. To reduce interference, it is also important to use metal containers and shielded cables.

#6. Antenna Layout

If the PCB contains antennas to facilitate wireless communication, it is important to ensure that layout errors related to the antenna are avoided.

To maximize power transfer, it is important to adapt the impedance between the transceiver and the antenna. Typically, the transmission line that connects the transceiver with the antenna should have an impedance of 50 Ω. To adjust the impedance accurately, the use of a Pi (LC) tuner filter is ideal. It needs to be placed between the antenna and the receiver.

#7. Blind or Buried Vias

Via holes go a long way in solving complex routing issues. In their use, however, some amount of caution is required.

Blind vias should be used to connect an external layer with an internal one. Buried vias, on the other hand, must be used to connect two internal layers. Through hole vias need to be used to connect two external layers and an internal layer. In creating a via hole, the following things need to be taken in consideration:

  • Hole size
  • Tolerances, and other attributes.

Also, since blind and buried vias come at a cost, it is also prudent to plan their use judiciously.

Here, in this article we have mentioned some of the most common mistakes that can take place during PCB design process. Make sure to read these guidelines and follow these steps to create a successful PCB design project.

At Technotronix, our broad experience in offering PCB Layout with one or more insulating layers containing signal trace with an exact power and ground for the layout has made us one of the kingpins in providing PCB manufacturing and layout services. Submit your any custom PCB layout and design service requirements via PCB layout quote form along with BOM (Bill of Material) and Gerber files and we will get back to you soon. Alternatively, you can email your requirements at [email protected] or call us at 714/630-9200.