Top 10 Best PCB routing practices!

By | Date posted: | Last updated: January 28, 2023

Routing a circuit board comes with its own set of challenges. Especially when we are dealing with miniaturized boards and high-speed signals, the challenges get further enhanced. If you are looking for industry best practices when it comes to PCB routing for high-speed designs, here are 10 handy tips:

PCB routing practices

1. Have a common ground plane below signal traces

It is recommended that high-speed signals be routed over a solid ground plane. Using at least a 4-layer PCB is also beneficial, as then one of the layers can be used as a ground plane. While sometimes a double-sided PCB may be required to be used, the fact remains that when you need to route tracks on both sides, you do not get a solid ground plane. In such cases, at least under critical sections, a ground plane should be attempted. Broadly, full single ground planes offer better results than split grounds.

2. Ensure vias are placed in a grid

It is imperative that blind and buried vias are positioned accurately as otherwise it can result in hotspots. As a thumb rule, vias should be placed 15 mils apart from each other.

3. Ensure that trace bends are kept at the minimum

When routing high-speed signals, bends need to be kept at a minimum. In the situation where you need to keep the bends, 135 degrees is a far better option than 90 degrees. This will ensure that PCB etching is smooth.

4. Maintain a minimum distance between traces

This will ensure that there is minimal crosstalk as among other things, crosstalk is a factor of the distance between traces. Due emphasis therefore needs to be placed on the fact that the traces aren’t closer than desirable.

5. Daisy Chain Routing

If long stub traces are used, there is often a compliance issue with EMC standards. Besides this, signal integrity can be negatively affected. In case it is important to use pull-up or pull-down resistors, it is recommended to use daisy chain routing.

6. Avoid placing components between differential pairs

It is important to have differential pairs parallel to each other. Also, symmetrical routing should be followed for differential pairs. Placing of vias or components between the differential pairs is a strict no-no as it could lead to issues with impedance. In case you need to include serial coupling capacitors, ensure that they are placed symmetrically. Another aspect to keep into account is that both traces should be routed on the same layer.

7. Avoid a split plane while routing signals

The use of a split plane needs to be avoided as such a signal path can lead to EMI issues. If you have a situation where the plane is split between a sink & source, the signal trace is best routed around it. Similarly, if a signal needs to be routed over two different reference planes, stitching capacitors should be used. The position of the capacitor is crucial as the distance between the forward & return path needs to be kept small.

8. Ensure that the analog & digital ground planes are kept separate

This will make it easy to determine which components should be connected to the digital ground & which one to the analog ground. For mixed signal circuits, the analog & digital ground needs to be connected at a point. Zero-Ohm resistors between analog & digital sections are recommended. Also, if the mixed signal design has split planes, you need to take care to see that the digital signal is not routed over an analog ground plane & vice versa.

9. Create a virtual separation in the layout with respect to analog & digital ground

This virtual separation needs to be kept in mind during the routing process. Due care needs to be maintained to see that the analog or digital trace does not crossover to the other side.

10. Keep the width of the component as close as possible to the track width

By doing this, the impedance matching issues between the track & the component pad can be addressed.

With the above tips, you can ensure that your design is robust & that there are no manufacturability issues, causing you loss of precious time when the industrial printed circuit board comes to the manufacturing stage.

Technotronix provides a one-stop solution for electronics manufacturing services with specialized support, reliable testing, and multi-functional features. In case if you have any questions, please feel free to contact us via email at [email protected] or call us at 714/630-9200.

PCB vs Breadboard – What is the difference?

By | Date posted: | Last updated: January 24, 2023
PCB vs Breadboard

A printed circuit board(PCB), which is an integral part of all electronic devices, is an electrical board that offers circuit connections. A wide variety of electronic components are soldered on the board depending on the bespoke requirements.

Breadboards, also referred to as protoboards, are solderless boards that are either single or double sided. These have holes that are used to put the terminals of components & wires. A key difference between the two is also that breadboards aren’t specific to a project. Breadboards derive their name from the fact that in the early days people made use of pieces of wood that they cut bread on to connect the circuits. Usually, breadboards comprise of four banks of thirty rows of holes. 

Let us look at some of the differences between PCB vs Breadboard in detail:

PCB vs Breadboard – Key Differences

1. Components

A key difference between the two is that the components of a breadboard aren’t soldered and hence can be changed or removed. On the other hand, the components in the PCB are either surface mounted or through hole mounted and hence more permanent.

2. Phase of Operation

The use of breadboards is in the development phase while PCBs are used for final electronic products. With PCBs, therefore, it is imperative that they be designed as per the exact requirements and then be manufactured and assembled.

3. Carrying Capacity

When it comes to carrying capacity, PCBs are far superior than breadboards. In case of breadboards, since the components are connected by wires, the current carrying capacity is minimum. Additionally, when it comes to PCBs terminals can be added. The same, however, isn’t possible in case of breadboards.

4. Complexity

As opposed to PCBs, breadboards come with a simple structure. Even the simplest form of PCBs has a structure that is complex compared to breadboards. Typically, a breadboard comprises of distribution buses and holes. In case of a PCB, its structure has at its very minimum a substrate layer, a copper layer, solder mask & silkscreen.

5. Rigidity

While Breadboards are rigid, the key advantage with PCBs is that they could be rigid, flexible or rigid-flex, to suit a wide variety of requirements.

6. Support

As for the support offered by each of them, while breadboards support components mechanically, the support offered by PCBs is far more robust since it connects the circuitry mechanically as well as electrically.

7. Electrical Function

Breadboards perform no electrical function. In case of a PCB, however, there are a wide variety of functions such as transferring radio signals, dissipating heat, and more.

8. Look and feel

When it comes to the look and feel, PCBs are available in several different colors on account of the color of the silkscreen. The look and feel of breadboards, however, remain basic.

Between a PCB & a breadboard, which is superior?

It is hard to come to a one-size-fits-all answer to that question. This is because the usability really depends on your bespoke needs. If you are at the early developmental stages, breadboards work well. They are low in cost, offer reusability and more. As a hobbyist you in any case need to start with a breadboard and then move on to advanced projects. Even as a professional, you can use breadboards for troubleshooting, experiments and more. Breadboard is also used for easy prototyping. Another alternative to the breadboard is the perforated board. It is a thin piece panel that has lined up perforations. However, since the perforations have no electric connections, the components need to be connected through soldering or wire wrapping.

When you are looking at a permanent electric device, you sure need a more sophisticated device that is permanent and can withstand different environmental conditions. A PCB is a clear winner in such cases.

Can you turn a breadboard into a PCB?

It is important to remember that breadboards are the initial step before you develop a PCB. Breadboards work well for testing your schematics. Once this aspect is done, you need to generate Gerber Files for manufacturing of PCBs. The Gerber files are then sent to a professional PCB manufacturer, who then takes to fabricating and assembling the PCB.

We are fully equipped to handle your PCB manufacturing requirements. At Technotronix, we follow industry best practices to ensure we deliver cutting-edge products. In case if you have any questions, please feel free to contact us via email at [email protected] or fill out the form below to request a free quote now.

Top Circuit Board Component Placement Guidelines

By | Date posted: | Last updated: December 30, 2022
Circuit Board Component

With miniaturization becoming the order of the day, the one thing that is becoming extremely complex is PCB layout. Not only does it have to cater to reduced space but also to increased functional requirements. Besides, with high-speed circuitry what is needed is layout precision so that there are no issues related to signal integrity or to do with effective heat dissipation.

Therefore, the important thing is to balance the manufacturing requirements along with the circuit board component placement requirements. Some of the other factors that need to be kept in mind include the fact that at the time of testing, there needs to be accessibility of parts.

Functional needs of the circuitry

  • The process needs to begin with floor planning. You need to figure out where you will place the digital, analog, RF & power areas. It is imperative that these areas are kept isolated so that signal integrity is maintained.
  • Fixed components such as connectors must be placed first.
  • While transitional components can infringe into other areas, the rest of the components should not.
  • Ensure that the routing channels aren’t choked and that there is space for escape & bus routing. It is also important to ensure clear return paths and therefore vias should not block the signal return paths.
  • The components of high-speed signals should be placed close together & the connections need to be short.
  • The components of power supply need to be placed close together. Additionally, power supply components should be placed on the same layer. This ensures that there is no need for any vias.
  • Components that generate heat such as processors, need to be placed towards the center of the board so that there is efficient heat dissipation. You also need to be careful about the management of the airflow. Proper placement of heat sinks and other heat dissipation devices is also important.

Circuit Board Component Placement for Manufacturing

  • For SMT parts that cannot be wave soldered, ensure that there is extra clearance available. That way you will be able to mask these SMT parts.
  • Components that can be wave soldered should have their pins perpendicular to the direction of travel through the wave.
  • In terms of component size, small SMT components should not be directly placed behind the large components.
  • Through-hole connectors need to be oriented in such a manner that their pins travel perpendicular to the wave.
  • Tall components should not be placed on the back of the board.

Circuit Board Component Placement for Accessibility

  • At the testing stage it is important that there be access to the board in terms of plugging in cables, attaching wire clips & more.
  • PCB layout needs to take into account the fact that wire harnesses have to be fixed, batteries have to be replaces & more. The layout, therefore, needs to allow accessibility for this.
  • Component placement also needs to take into account the fact that intra-system connections may need to go through a redesign.
  • The circuit board needs to be designed in a manner that test points are designed into it. Test points, in turn, have their own specific requirements when it comes to placement. Some of the aspects to take care of include test point to test point spacing, test point to component spacing, and test point to board edge spacing.
  • The arrangement of the board in the manufacturing panel also impacts the placement of components. For panels that use a scoring tool for separation, due care needs to be taken to see that components have enough clearance from the edge. Similarly, the panels that use break-out tabs need to ensure that the components are kept away from the tabs.
  • In cases where the board is conformally coated, it is worth remembering that unique components are placed at the edge so that they do not dip in the coating.

To sum up

To avoid functional and manufacturing problems in your design, The circuit board components need to be placed considering a wide variety of factors such as:

  • Functional Requirements
  • Manufacturing Requirements
  • Accessibility of parts

Due consideration given to each of these aspects ensures that the PCB works as planned and that there are no costly issues to contend with at a later stage.

Technotronix provides a one-stop solution for electronics manufacturing services with specialized support, reliable testing, and multi-functional features. In case if you have any questions, please feel free to contact us via email at [email protected] or call us at 714/630-9200.

What are the benefits and limitations of custom PCB boards?

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

As electronic devices become more complex and need to fit into increasingly smaller spaces due to miniaturization, custom PCB boards are gaining popularity. Custom PCBs are ideal for integrating circuits while conserving space in sophisticated devices.

However, it’s crucial to recognize that custom PCBs aren’t a cure-all. They come with their own set of benefits and limitations. Additionally, incorporating printed circuit board assembly services and PCB fabrication into your design process can further enhance the performance and efficiency of your electronic devices. Let’s delve into both the advantages and limitations of custom PCBs in detail.

Benefits of custom PCB Boards

The big advantages of custom PCBs include:

  • They ensure that you can incorporate condensed circuitry in small spaces. The fact that you can design a printed circuit board as per your size and shape requirements, it is a definite plus given the shrinking size of electronic appliances.
  • The big advantage with a custom PCB is also that you can control the location of every component. Also, you are also not just limited to through-hole components. Among other things, with this kind of control the parasitic properties of the circuits can be mitigated.
  • With due emphasis laid on quality in producing a custom board, durability of the board is high.
  • With automated production not only is labor cost kept under check, the probability of repeatability also increases.
  • With legends being directly printed on the board there is no need for decals.
  • With integrated LED lights functionality can be easily verified.
  • There is also a benefit from the appearance of the device since a custom designed PCB looks very professional. Clients & investors therefore perceive the product highly.
  • In terms of cost, the general view is that the cost of a custom PCB boards is higher, however, this isn’t always the case if you take into account long term factors such as the fact that they need less rework, you could use the Gerber and schematics files to build other prototypes and more. In the long run, therefore, you tend to benefit from the cost of the board.

Limitations of custom PCB Boards

Disadvantages of custom PCBs stem from the fact that:

  • The initial design time required is high.
  • You need to be careful as high amperage can negatively impact the PCB.
  • It is sometimes difficult to troubleshoot on account of the enclosures that you need to provide.
  • It is important to understand that custom PCBs do not score high in terms of flexibility. PCB technology is extremely dynamic. Hence the chances of the design becoming obsolete are extremely high too.
  • With quick time-to-market being a big source of competitive advantage, custom PCBs tend to lose out as the initial design time is high. If you are working against tight timelines, therefore, custom PCBs may not be your best bet.
  • If you are looking at low volume operations, once again custom PCB boards may not be your best bet.
  • Similarly, if your design requires frequent changes, custom PCBs are not likely to be your go-to option.

To sum up

Whether or not you should go in for a custom PCB depends on a wide variety of factors. Some of the factors to consider include how complex your project is, what kind of volumes you are looking at and more. Also, custom PCBs involve a certain initial cost as well as involve a certain time. However, what also needs to be given due weightage is the fact that custom PCBs come with a robustness and that the PCB design can be easily recycled.

In making a decision for a custom PCB what you need to ensure is the choice of the right electronic contract manufacturer. It is imperative that you go with a contract manufacturer who has the requisite experience and is equipped with the necessary industry best practices. This will ensure that you do not need to reinvent the wheel. An experienced contract manufacturer will also ensure that the PCB is tested thoroughly so that there are no errors at a later stage. What is also guaranteed when you go with the right contract manufacturer is their quick turnaround time as well as the fact that they offer you superior customer service.

Technotronix is one of the leading PCB manufacturers in the USA, providing custom, lead-free and RoHS compliant PCB manufacturing solutions. Whether your requirement is for prototypes or large production runs, we have you covered.

Email us on [email protected] or call us on 714/630-9200 to solve your queries related to our custom PCB services.