How to make a Bluetooth PCB？
Bluetooth PCB is very common in our daily life. And you can find it in your smart phone other Bluetooth enabled devices. Bluetooth is a form of communication that utilizes radio frequency to connect with different devices. The paired devices exchange information serially with the master Bluetooth device. The interaction between the paired devices can be done through the master Bluetooth device, which acts as a facilitator. Bluetooth PCB is the main force driving wireless headsets, remote controls, wireless speakers to IoT (Internet of Things) application. They are two-layered PCBs but have only a single plate. You will find the layers on both sides of the leaves. In this passage we will discover how Bluetooth technology works.If you want to order PCB product, please check and custom your order online. What is the working principle of Bluetooth PCB? The principle behind the working of a Bluetooth circuit board is straightforward. An antenna is located on the Bluetooth PCB, which receives the signal sent out by a Bluetooth device. The message is then sent to the output after being processed inside the circuit board. Different Bluetooth profiles are used to facilitate communication between devices based on the application of the Bluetooth device. For example, the Audio/Video Remote Control Profile (AVRCP) is used for communication with audio-video devices and found in remote controls of hi-fi equipment and TVs. What are the components of Bluetooth PCB? A Bluetooth circuit board also contains a minimum of 2 inductors, which can fine-tune the impedance of the antenna to improve the reception and sending of information. The modules have 4 IO pins, which are the State, Enabled, communication, and power supply options. You can also find multiple resistors, diodes, and capacitors placed on the Bluetooth circuit board. Apart from the above components, other parts such as chips, voltage regulators, and the crystal-based clock can also be found. The Bluetooth circuit board requires careful attention while assembling, especially with the antennae for its proper functioning. Bluetooth circuit boards are found within Bluetooth-enabled devices. What are the applications of Bluetooth PCB? Bluetooth boards exist in the devices and devices we use every day without careful consideration. Anything that uses wireless connection can be using Bluetooth radio frequencies even without your knowledge. So let us go over some typical applications of Bluetooth circuit boards.1. Wireless Headsets and Earphones Fancy listening to music on the go without the hassle of wires messing up? Most of the wireless headsets and earphones use Bluetooth technology for the transmission of audio and voice signals. The Bluetooth circuit board is the silent performer enabling the connection between your audio device and your headset, making you listen to your favorite songs. You can also talk over the Bluetooth connection using voice signals courtesy of the Bluetooth PCB.2. Cordless Keyboards and Mouse An impressive number of wireless keyboards and mouse relies on Bluetooth circuit boards to connect to your computer and help you do your work. Earlier wireless connections were made over infra-red frequency, but Bluetooth is a far more superior alternative used these days.Even printers, scanners, and other computer peripherals can be connected using Bluetooth technology. Bluetooth SpeakersBluetooth speakers are a fad these days, and everybody is carrying one. The wireless speakers have an inbuilt Bluetooth circuit board as a part of the main circuit board responsible for syncing with your audio player or smart phone. Multimedia TransferWe don't think twice before transferring songs or videos between devices over a Bluetooth connection. All such methods are sending out and receiving multimedia content, and other files are equipped with a Bluetooth circuit board. The smart phone you are using also has a Bluetooth circuit board, which lets it play songs through a wireless speaker or headset and transfer files and movies from one phone to another. Automatic SynchronizationBluetooth connection is the spinal cord of any device which has to do with IoT. This new technology creates a bright world by connecting everything and giving you control over it. For example, you may pick up the temperature of the machines in a factory on your smartphone over a connection established over Bluetooth frequency. Such devices use Bluetooth circuit boards for automatic synchronization and exchange of information between different touch points.Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 06/11/2021 16:59
How to make Aluminum PCB？
When you hear the names Aluminum Clad, Aluminum base, Metal Clad Printed Circuit Board (MCPCB), Insulated Metal Substrate (IMS), Thermally Conductive PCBs, etc., do know that the PCB type in question is synonymous to Aluminum PCBs. From the name, you can already tell that aluminum PCBs contain aluminum as one of the materials. Indeed, these PCBs have a metal core at the base material, with aluminum being one of the critical components. What's more, there's the presence of a thin layer of thermal, dielectric material and electrically insulating material. If you want to order PCB product, please check and custom your order online.Why to use Aluminum PCB? Since the emergence of aluminum PCB technology in the 1970s, several industries and individuals have augmented demand for production. Suppose you're planning on using applications that have heat dissipation and wish to control the temperatures. In that case, Aluminum PCB is the right choice for you. Aluminum is known for transferring heat away from significant components on the board. In doing so, your PCB is kept free from the dangers of heat damage. Moreover, it is highly durable and can serve you a long time compared to other materials like fiberglass. What are the types of Aluminum PCB? Even though all-aluminum clads work the same way, i.e., in heat dissipation, different types have individual characteristics based on their design and structure. The following are the types of aluminum clads that you should be know. Through-hole aluminum PCBWhen we design through-hole aluminum PCB, the manufacturer backfills and pre-drills a single aluminum layer and then applies the laminate material. There will be a formation of a core of multilayer constructions after this process. Afterward, they laminate the thermal materials on the two sides of the board with thermal bonding materials. The final touch involves drilling on the assembly. Flexible aluminum PCBA flexible aluminum PCB is a recently marketed circuit board with a polyimide resin integrated with ceramic filters upon purchase. The two materials’ essence is to increase insulation, flexibility (you can twist or fold the PCB to any shape and retain the form), and thermal efficiency. What’s more, their application is cost-effective since you won’t need to purchase connectors or cables. It’s disadvantageous because you can’t alter or modify the final product once you acquire a specific shape. Multilayer aluminum printed circuit boardMultilayer aluminum PCBs have multiple-layer of thermally conductive dielectrics. The design constitutes one or more layers of circuitry found in the dielectric with blind vias representing thermal or signal vias. An advantage to using multilayer IMS PCB is the straightforward and operative solution they offer for heat conductivity in complex products. Contrary to that, they’re costly and can’t easily engage in heat transfer in single layer designs. Their application is often in power supply products. High thermal conductivity aluminum PCBIn this type of PCB; the insulating layer is an epoxy resin material. The epoxy resin should have excellent thermal conductivity. High-frequency aluminum PCBWith high-frequency aluminum PCB, the insulating layer has a polyolefin or polyimide material. Other times, it can be woven fiberglass between an epoxy resin. The purpose of the materials is to improve the flexibility of the PCB. How to solve difficulties during the aluminum PCB manufacturing? Copper etchingIdeally, the copper foil you use in the circuit layer should be thick. A higher standard than this, which is more than 3oz, will force you to compensate for the etching’s width requirement. Failure to do so will make the width intolerant to the etching. Therefore, you need to control the etching factors carefully, compensation being a major one. Solder mask printingA thick copper foil in this PCB design hinders solder mask printing of aluminum PCBs. In other words, a thick layered trace copper leads the etched image to have a vast difference in the trace surface and baseboard. Thus, printing becomes difficult. A quick way to solve this problem is by using a quality solder mask oil. Alternatively, you can fill in the resin before the solder mask. Machine-madeManufacturing an IMS involves drilling mechanically, molding, and v-scoring, among others, centered on the internal via or holes. To combat this, use the electric milling and professional milling cutter for manufacturing products of a lower volume. Additionally, adjust the drilling parameters to stop burr production.Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 06/10/2021 17:52
What is the difference between PCB and breadboard？
The most commonly used types of boards over which projects and circuits are assembled are breadboard and PCB or printed circuit board. In breadboard, the circuit is designed with the use of wire to make connection among the components while in PCB components are linked or assembled at the copper wire tracings that are designed over the board or substrate and symbols of different components are designed at the board over which components are placed to make circuits. In this post, we will cover a detailed comparison between PCB and Bread. So let’s get started with Difference between PCB and Breadboard.If you want to order PCB product, please check and custom your order online.What is the definition of PCBs? The easiest and probably the most ubiquitous example of a PCB is your computer’s motherboard. It connects and facilitates the communication between electronic components within your computer. It achieves this primarily through a collection of copper traces, tracks, and pads. Generally, in appearance, a PCB is a green layered piece of laminated board. The Austrian inventor Paul Eisler developed the first official printed circuit board in 1936 while working on a radio set. Companies did not manufacture PCBs regularly until the 1950s. The first PCB started with a single layer, but modern PCBs now consist of over twenty layers. Before an engineer or fabrication company can fully assemble a PCB, it needs to be prototyped. This prototype will be a proof of concept, allowing you to test your design. Nevertheless, as with your motherboard, the PCB is the carrier, foundation, and support for all your other devices within your system. You will find PCBs in smartphones, microcontrollers, smart TVs, etc. What is the definition of breadboard? In appearance, breadboards are rectangular plastic consoles perforated with square holes and engraved with various symbols and lines. Ronald J. Portugal invented the first solderless breadboard in 1971. You may have heard it referred to as a solderless, proto board, plug board, or terminal array board. It is uncertain where the name “breadboard” originates. However, we do know that electronic engineers in the past used to connect components by wire-wrapping them and nailing them into a wooden board. Essentially, they would use these wooden boards as their bases. Another theory states that an engineer had an idea for a vacuum tube device once upon a time. The only thing he could use for the base was his wife’s breadboard. Therefore, breadboards may get their names from engineers using wooden boards to prototype their ideas. The layout of a breadboard is quite similar to that of a PCB – at least in concept. The perforations on the breadboard allow you to connect various electronic components. These components can range from transistors to LEDs. Not only do we use breadboards for prototyping, but we also use them extensively for educational purposes. In fact, in the same way, you can find build kits for your Raspberry Pi 4 project ideas, you can find various breadboard kits too. They often come with power supply units, jumpers, wires, resistors, transistors, and other components. You can even connect them to PCB based microcontrollers. What is the advantage of PCB? On this board circuits created are have a permanent assembly. The current-carrying capability of this board is larger than the breadboard to draw more current we can create different paths that do not exist in the breadboard. To make exterior linking there is an addition of different components is used in this board. And this board is mounted with a heat sink that makes it rigid. The circuit created on this board has clean look while the breadboard circuit shows complicated circuit assembly. In almost every type of electronic module, this board is used. The circuit understanding on the PCB board is very easy due to simple assembly. What is the advantage of breadboard? The main advantages of the breadboard are discussed here. Through the use of this board, we can vary the linking connections of devices use in circuits according to our requirement. This board helps us to do the replacement of companies used in the circuit when we needed. Construction of the circuit on this board is a very speedy and easy process due to the absence of soldering. Here are chief benefits over PCB board is that we can link ammeter to this board at any point where we current has to measure but these features do not exist for PCB board.Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 06/08/2021 17:48
How to protect PCB from moisture？
During the PCB manufacturing process, the design of PCB will affect whether moisture is more or less likely to be an issue. One of the most troubling issues with printed circuit boards involves the presence of moisture. If moisture exists within a PCB, the destabilization caused by it is liable to have a delaminating effect on the surface elements. Anytime soldering or rework is applied to the PCB, the delamination could easily expand as a result of the moisture contents. In this passage, we will tell you everything about how to protect PCB from moisture, follow us and read the content we provide.If you want to order PCB product, please check and custom your order online. Moisture effect on PCB The presence of moisture can lead to various functional failures on a PCB, depending on which components or conductive paths come into contact with it as diffusion takes hold. Moisture can fester in the epoxy glass, resin or glass interfaces and cracks in a board. Problems commonly associated with moisture include slowed circuit speeds and increased delay times with the functions of a corresponding device. If the problem exceeds a certain limit, the device might simply fail to activate. Tests have been conducted that show the effects of moisture absorption and desorption in printed circuit boards. In a PCB with plated through-holes of varying density, trapped amounts of moisture have different desorption rates based on the distance between each hole. In PCBs that are heavily saturated, desorption can take hundreds of hours within high-temperature environments. If a PCB is placed in an environment where the atmospheric moisture pressure exceeds the resistance of the board and its components, moisture can penetrate the PCB. To prevent moisture delamination from taking effect on a PCB, soldering should be performed only with high temperatures of less than 0.1 percent moisture content or with low temperatures of less than 0.2 percent moisture content. High-temperature soldering would hover around 260 degrees Celsius, while low-temperature soldering would be in the ballpark of 230 degrees Celsius. How to remove moisture from PCB？ When measurements are made of a PCB’s ability to store electric energy, a change in moisture content can be detected within the board. Capacitance sensors are used in this process. Capacitance levels move in inverse proportion to hole density. If the latter is high, the former is low because there’s less distance between the moisture and the surface but more space for the moisture to escape. In non-PTH PCBs, capacitance decreases at a more rapid pace. As such, less bake time is needed for these boards to have a low enough moisture level. On PTH boards, there’s less exposed surface room for the moisture to escape. Due to the inverse effect of copper planes on the desorption process, they should be baked with consideration for their design. On one hand, you can empty moisture more effectively from a board by running the baking process for longer periods, but doing so could reduce the board’s solder ability and functional capacity. Consequently, bake time should be measured to avoid these possible side effects. The process of moisture removal does not always yield predictable results. For example, a pair of identical copper planes could undergo a central flare-up of moisture as the baking gets underway, only to diffuse moments later. If this momentary swell of moisture occurs in an area of the board where delamination is most probable, it could be the unintended side effect of baking. On some boards, moisture removal is simply not possible once the moisture has diffused through several layers. Therefore, it’s crucial to employ measures to prevent moisture from entering into the board during the initial process of assembly. How to protect PCB from moisture？ During the manufacturing of PCBs, the lamination process should be conducted in a temperature-controlled environment where the air system is regulated with desiccant drying agents. It’s also crucial to wear fresh gloves during each work cycle to avoid the spread of contamination between different components. The very process of PCB lamination has a dehydrating effect on the finished product. It’s during this stage that the prepregs and cores are put into place and the layers are bonded into a single board. Some manufacturers apply a low-pressure vacuum effect during this stage to prevent internal voids that could possibly trap moisture within the layers. Among certain PCB fabricators, it’s common practice to bake the prepregs prior to lamination. The goal here is to prevent moisture pockets and blisters from forming on the finished board. This step is most useful when the prepreg has spent a certain length of time beforehand in an unregulated storage environment. Otherwise, this step is generally not necessary. One of the most effective means of moisture prevention in a PCB is meshed copper planes, which inhibit moisture travel between layers as well as in and out of boards. Meshed copper planes also serve as a stronger bonding material between layers. However, their presence in a PCB can reduce the board’s electrical capacity.Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 06/07/2021 18:10
How to identify PCB manufacturer?
If you are going to order PCB products, it is pretty important for you to find a reliable PCB manufacturer to produce the boards you want. And a professional manufacturer will determine the quality and performance of the finished PCB. Please check and read the content we provide to learn more knowledge about it.If you want to order PCB product, please check and custom your order online. What are the tips before choosing PCB manufacturer? When choosing a manufacturer, you should have some questions prepared. You can get the answers to these questions through your own research using the company’s website and other online resources such as online reviews. You can also get the answers by asking the company directly. Getting the answers to these questions will help you determine whether a given PCB manufacturer is the best one for the job. 1. How long have you been doing this?Experience is crucial in PCB manufacturing. It provides insight into the amount of knowledge and resources a manufacturer may have, their competence and how well they’ve been able to adapt over time to changes in the industry. 2. What certifications do you have?Certifications provide additional insight into how qualified a manufacturer is. To receive certification, a third party typically needs to verify that the company complies with a standard or other requirement. The International Organization for Standardization (ISO) publishes standards related to quality management, such as ISO 9001, as well as other areas. IPC produces standards that are specific to the PCB and electronics manufacturing industries. Make sure that each manufacturer you’re considering working with is capable of complying with all of the standards that apply to your industry and products. This, of course, includes broad regulations and standards such as restriction of hazardous substances (RoHS) but also includes requirements that relate to your industry in particular. This is one area in which working with a company that has experience with your industry is valuable. 3. What makes your company unique?This question can help you make your final decision once you’ve found several similar manufacturers that provide the products and services you need. To answer this question, you can explore the value-added services each manufacturer offers and even just ask a company representative what they believe sets their organization apart. How to identify PCB manufacturer? It can be difficult to narrow down your PCB manufacturer choices, since there are so many options and, at first glance, many companies seem to be quite similar. Some topics you should investigate early in your search include a company’s products, services, capabilities and facilities. 1. ProductsGet information about what types of PCBs each manufacturer offers. This may include rigid, flexible and rigid-flex boards as well as metal core, aluminum-backed and hybrid boards. Additionally, ask about the substrates the companies use for their boards. Aluminum boards, for example, offer high thermal conductivity and excellent electrical insulation, while heavy copper boards are ideal for high current applications. Product QualityYou’ll also want to explore the quality of the boards each manufacturer provides and the quality control processes they have in place. Some quality control measures to look for include: PricePrice is another factor that is always essential to consider. Of course, you want to minimize your costs, but you must also be careful that the quality of your boards remains sufficient. You need to find a manufacturer that provides products that meet your quality standards while remaining in your price range. One aspect of cost to consider is the initial quote. Once you provide a manufacturer with information about your project, they can provide you with a quote. To ensure the quote they give you is an actual estimate of the total cost, ask if there will be any other fees added later in the order process. Additionally, ask about potential discounts for bulk orders or frequent orders. Some manufacturers will offer discounts or special arrangements for return customers. Ask whether these opportunities exist to ensure you’re getting the best possible price. 2. ServicesYou’ll also need to determine which services each manufacturer offers and make sure they can provide the ones you need. Working with companies that provide numerous services comes with the advantage of not having to switch between companies throughout the production process. Sometimes, though, you might want a more specialized company. Beyond assembly, here are some of the services to look for: PrototypingCreating a prototype PCB before going to production can reduce the total timeframe and costs of your production process. Creating prototypes gives you sample boards you can use to test your design and then fix problems and make improvements, which is much more cost-effective to do earlier in the production process. Layout and design servicesLayout and design services can help you to speed up your production process. Some companies will do a complete design for you after you give them basic information about what you need. You may be able to send in existing files and have a company make changes or help you solve a design problem. File review and analysisSome PCB manufacturers will provide a review and analysis of your design before they manufacture. This serves as a final check for design errors and defects and helps ensure that the manufacturer has all of the necessary files and information before beginning manufacturing, helping to avoid delays after you place your order. SMT stencil productionSMT stencils, which are made of stainless steel foil and are laser cut, help to ensure that the solder paste is printed in the correct places on the PCB. Using a stencil to apply solder paste is much more accurate than applying it by hand. PanelizationPanelization refers to grouping boards to enable faster processing and is typically used for high-volume production. If you plan on placing high-volume orders, you may want to look for a manufacturer that provides panelization while still allowing for any customization you may need. This can significantly decrease your timeframe for production. 3. Capabilities You will also need to make sure that the company in question has the capabilities necessary for providing the PCB solutions you need. Gather information about the following capabilities. Order quantityWhat are the maximum and minimum order sizes that each manufacturer can fill within your required timeframe? Lead timeYou’ll want to get information on each company’s lead time for prototypes, small volume, medium volume and high volume orders. Ensure that the company’s estimated delivery time for the type of order you’ll be placing is compatible with your requirements. Additionally, check whether the company provides a quick turnaround service for rush orders. Some manufacturers offer an order tracking service, which enables you to easily the status of your order and when you can expect it to arrive. Number of layersConsider whether a manufacturer can provide bare, single-layer, double-layer and multi-layer boards as well as how many layers they can accommodate. The number of layers likely varies for flexible, flex-rigid and rigid boards, so make sure you get the details for the types of boards you plan on ordering. Surface finish optionsPCB surface finishes protect the copper surface of boards from corrosion and provide other advantages, such as making soldering easier. There are a variety of possible surface finish options available, and different PCB manufacturers may offer different ones. Possible surface finishes include electroless nickel immersion gold (ENIG), immersion silver, immersion tin, hot air solder leveling (HASL), organic solderability preservative (OSP) and hard gold. Via optionsWhat types of vias can each manufacturer provide? Ensure that each manufacturer can provide the kinds of vias you need, whether that’s copper-filled vias, blind vias, buried vias or micro vias. Controlled impedance modelingFor boards that operate in high frequency ranges, you may need controlled impedance. If you need repeatable high-frequency performance, check that manufacturers offer controlled impedance modeling and have knowledge in trace impedance. Specs and tolerancesWhat kinds of tolerances can each manufacturer manufacture to, and do they meet your requirements? One critical spec to check is the drill aspect ratio, which refers to the ratio of the PCB’s thickness to the drilled hole’s diameter and relates to the ability to provide copper plated holes using chemical processes. As the aspect ratio increases — that is, as the holes get smaller — achieving reliable plating becomes more difficult. Other important specs include outer layer trace and space, inner layer trace and space, minimum drilled hole, standard drilled hole, minimum pad size, minimum feature to edge and minimum core thickness.Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 06/07/2021 18:00
How to reduce electromagnetic interference in PCB?
During the PCB manufacturing process, electromagnetic interference will consistently plague PCB designers. So the testing of electromagnetic interference is extremely important to designers so that they could monitor electromagnetic compatibility and interference. Electromagnetic compatibility, or EMC, involves the generation, propagation and reception of electromagnetic energy, generally through poor design. Electromagnetic interference, or EMI, refers to the unwanted and damaging effects of EMC, as well as electromagnetic interference from environmental sources. Too much EMI can result in a defective or damaged product. Any PCB designer should follow EMC design rules to minimize the amount and effects of EMI. Please check and read the content we provide and get to learn how to reduce electromagnetic interference in PCB manufacturing.If you want to order PCB product, please check and custom your order online. Why to avoid electromagnetic interference? Sources of electromagnetic interference are all around us, and we can categorize them in several ways: SourceHuman-made EMI arises from electronic circuits. Naturally occurring EMI, on the other hand, can arise from environmental factors like cosmic noise and lightning. DurationContinuous interference is an EMI source that emits a constant signal, which most often appears as background noise. Impulse interference is intermittent, usually caused by switching systems, lightning and other non-constant sources. BandwidthNarrowband signals like those used by radio can encounter interference from oscillators and transmitters, though these sources only affect certain parts of the spectrum intermittently. Broadband interference affects high-data signals like TV and can come from many sources, including arc welders and solar noise. Whether human-made or environmental, EMI can be both costly and dangerous. It can disrupt communication channels and sensitive devices. EMI is a notable concern in the medical field, where wirelesses device usage is on the rise. Unfortunately, EMI can affect the functionality of medical equipment like ventilators, ECG monitors, cardiac monitors and defibrillators. In other industries, EMI can disrupt sensors and navigational systems. The result in all cases is a disturbance of equipment that may be responsible for the health and safety of its users. However, the most common source of EMI — and the most problematic source for designers — is internal. Poor PCB design can result in incompatible signals interfering with one another on the board. This interference can ultimately cause the board to fail. Designers must ensure that interference is kept to a minimum and any signals let off are compatible so as not to result in interference. How to prevent electromagnetic interference in PCB? These essential design principles can help prevent and fix these electromagnetic problems in a printed circuit board design. 1. Ground Plane Designing a PCB’s ground plane is the most significant step, and it’s crucial for reducing EMI. The ground plane is your first line of defense against EMI since all circuits require a ground to work. Some common best practices for ground design to reduce EMI include: Maximize ground area: Increase the ground area as much as possible within the PCB. Signals can disperse more easily with more area, reducing emissions, cross-talk and noise. If the ground plane is too small, you could possibly add another layer and create a multi-layer PCB. This design solution provides more options for handling high-speed traces. Use solid planes: Especially in multi-layer PCBs, a solid ground plane is an ideal option. Copper-thieving and hashed ground planes usually result in higher impedance levels. Solid ground planes, on the other hand, provide lower levels. Connect each component: Connect every part to a ground plane or point. The ground plane acts as a neutralizing agent for board design, and floating components don’t fully make use of this. Be careful with split planes: Highly intricate PCB designs often include numerous regulated voltages, which should each have their own ground planes. Too many ground planes, however, increases fabrication cost. This issue is usually circumvented through the use of split planes, which create multiple ground sections on a single layer. However, designers should always use split planes carefully. Ensure you have a good reason to use a split plane and, if using one, make sure they are only connected at a single point. Multiple ground connections in a split-ground PCB can create loops, resulting in an antenna that radiates EMI. Connect bypass or decoupling capacitors: If the design includes bypass or decoupling capacitors, connect them to the ground plane. This act helps lessen the return current by reducing the size of the loop. Minimize signal length: The length of traces is important since the amount of time a signal takes to get to and from a source must be compatible. Otherwise, it can radiate EMI. Keep trace lengths are as short as possible and are about equal in length. 2. Trace Layout Traces are especially important for board design. Proper trace usage ensures properly propagated current. However, many problems can arise if traces are not arranged according to top EMC design rules. Traces are essentially conductive paths that contain flowing electrons while the circuit is active. Thus, these traces are one mistake away from creating a radiating antenna. A simple bend or cross can result in PCB electromagnetic interference. Some of the best rules for trace layout in PCB design include: Avoid right angles: Avoid angles of 45 degrees to 90 degrees for vias, traces and other parts. Capacitance increases as traces reach angles over 45 degrees. As a result, the characteristic impedance changes will lead to reflection. This reflection results in EMI. You can avoid this problem by rounding out traces that need to turn a corner or routing them through two or more angles of 45 degrees or less. Keep signals separate: Keep high-speed traces separate from low-speed signals and analog signals separate from digital ones. Close proximity can result in interference. Shorten return paths: Keep return current paths as short as possible, and route them along paths of least resistance. Return paths should be about the same length as transmit traces or shorter. Mind spacing: Two high-speed signals running in parallel create EMI through cross-talk, in which one trace is the “aggressor” and the other is the “victim.” The aggressor influences the victim trace through inductive and capacitive coupling, creating forward and backward current in the victim trace. You can minimize cross-talk by keeping a minimum spacing between traces. Generally, separate traces by twice the trace width. For example, if the traces are five-thousandths of an inch wide, keep a minimum distance of ten-thousandths of an inch or more between two parallel traces. Use vias carefully: Vias are necessary in PCB design because they let you take advantage of multiple layers in your boards when routing. However, designers must be careful when using them. Vias add their own inductance and capacitance effects to the mix, potentially resulting in reflections due to changes in characteristic impedance. Vias also increase trace length, which needs to be matched. When possible, avoid using vias for differential traces. If this is impossible, however, use them in both traces to compensate for the delay. 3. Component Arrangement Electronic components are the building blocks of an electronic circuit. However, arranging them improperly can cause several EMI issues. When designing a PCB, be mindful of each piece’s EMI impact. Some best practices for component layout in PCB design include the following: Separate analog and digital parts: As with traces, always separate analog and digital circuits and components. Placing analog and digital circuits in close proximity can result in cross-talk, among other issues. To avoid this, use shielding, multiple layers and separate grounds to place analog and digital signals as far away from each other as possible. Generally, it’s best to keep analog and digital signals on separate grounds altogether. Separate analog and high-speed pieces: Analog circuits carry high current, which can cause problems for high-speed traces and switching signals. Keep these away from one another and guard analog circuits with ground signal. On multi-layer PCBs, route analog traces so that a ground plane exists between the analog circuit and the switching or high-speed signals. Be careful with high-speed components: The faster and smaller the component is, the greater the amount of EMI it likely produces. You can combat this natural EMI through shielding and filtering, though it’s also a good idea to separate these components from others in the board design. Another measure to take is to keep high-speed signals and clocks as short as possible and adjacent to the ground plane. These measures help keep cross-talk, noise and radiation levels in check and within the acceptable level limits. 4. EMI Shielding Some components will produce EMI no matter what design rules you follow — especially small, high-speed parts. Fortunately, shielding and filtering can keep this EMI’s effects to a minimum. Some shielding and filtering options include the following: Component and board shielding: Physical shields are metallic packages that encapsulate all or part of a board. Their goal is to keep EMI from entering the board’s circuitry, though the specific methods vary based on the EMI’s source. For EMI that comes from within the system, component shields may be used to encase a specific component that produces EMI — thus connecting to ground, reducing the antenna loop size and absorbing EMI. Other shields may encase the entire board to protect against EMI from outside sources. A Faraday Cage, for example, is a thick protective enclosure designed to block RF waves. These devices are usually made of metal or conductive foam. Low-pass filtering: Sometimes, a PCB can include low pass filters to eliminate high-frequency noise from components. These filters suppress the noise from these part, allowing the current to continue on the return path without interference.Cable shielding: Cables that carry analog and digital currents create the greatest amount of EMI issues. They produce these issues by producing parasitic capacitance and inductance — a particular problem for high-frequency signals. Fortunately, shielding these cables and connecting them to ground at the front and back helps cancels out EMI interference.Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 06/07/2021 17:52
How to measure PCB trace resistance？
Every each material in the universe has resistance alongside other parasitic properties. PCB trace resistance is one of the crucial factors that need to be calculated and analyzed during the design stage. Although copper is the most used material in the printed circuit boards, it comes with different compositions and properties. The PCB trace resistance may lead to various design and implementation issues. The issues increase with the increase in the circuit complexity. In this passage we will talk about the details and methods of measuring PCB trace resistance, please check the content below for more information.If you want to order PCB product, please check and custom your order online. What is the calculation in PCB trace resistance? Calculating the PCB trace resistance is as simple as using the ohms law with the known parameters. Most design suits and development environments have integrated PCBs trace resistance calculator, which can estimate the resistance of the final copper trace on the board by providing the required and manufacturing profiles. And the calculator uses a standard formula to calculate the opposition so it will be constant universally. R = (ρ * L / (T * W)) * (1 + α * (TAMB – 25 °C)) L W and T represent the physical area of the trace height width and length. ΡCB represents the resistivity of the material, and α represents the temperature coefficient of the copper. But all of this calculation can only determine a close enough approximate value. The physical cost after production will vary slightly. How do you Calculate Trace Resistance? Specific formulas printed circuit boards all share in common to operate on a base level. If any part of this formula is wrong, there is not even any tracking resistance. One widespread mistake people make when it comes to detecting PCB trace resistance is that they have no idea how to calculate it. Visualizing the Printed Circuit Board Before revealing and analyzing this formula, we need to know what a conventional circuit board looks like, or at least on the surface. The most common circuit boards possess a thin layer of copper that is .009 mm and .38mm in thickness. The most common PCB traces are either 1 oz in weight or .03mm in height. The PCB Trace Resistance Equation Now that we know what a standard circuit board looks like, now we can present the formula and put this together. The method to calculate any conductor is: R = P × area. Each variable is assigned as follows: R – Resistance. P – Resistivity of any given material. Let's use this formula to determine the resistance of pure copper, heated to 25°C. Pure copper's resistivity rate at this particular temperature is 1.724. Knowing this, we need to multiply it against the area, which can range from 6-10 ohms per centimeter. Here's another example: Say we have an area of .375mm. If we multiply this by the resistivity, we'll get a resistance of 100 ohms, which would yield 20 ohms per centimeter. It is a small value, but because this formula is not perfect, it could result in some variance. It is one thing that can affect accuracy in PCB trace measurements. How to apply the PCB trace resistance equation? Another example of how this can play out is in resistance based current sensing circuits in power systems. If the sense resistor is 1 ohm and you use the same .025mm trace, the system will measure the resistance at 1100 ohms instead of the preferred 1000 ohms. That is quite a difference, and it can lead to a weaker currency than expected or even necessary. There do exist ways to work with the trace width that does not involve complicated calculations. These solutions can save much time, and you should consider before performing more complex calculations. You can regard these options to determine the trace width without needing to calculate the PCB trace width. The first of these can be done by merely eyeballing the width and increasing or lower it to see what kind of circuits are connected to it properly. It will do a couple of things. First, it will increase the area of copper, giving you a bit more room for experimentation with different ohm levels. Second, it will reduce the resistance of the copper on the board. It will also allow for a bit more testing to determine a proper trace width. For grid array packages, this is not an option. The option here would be to use a thicker copper layer and place it along with the original circuit board. It will increase the area and reduce resistance. One thing that should be made aware of about this is that using a thicker copper layer does require that you purchase the proper materials that are needed to create a more adhesive copper layer. It will cost some money.Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 06/05/2021 18:02
How to prevent PCB corrosion？
Corrosion is the process of oxidation that happens when oxygen bonds with metal, producing rust and causing the metal to flake off and lose its valuable chemical properties. Since printed circuit boards are largely made of metal and are exposed to oxygen, they must corrode eventually. However, not all metals are created equal when it comes to corrosion. Some metals corrode almost immediately while some seem to never corrode. Metals that are highly resistant to corrosion include: Graphite, Gold Silver, Copper-nickel alloy. Metals that are highly susceptible to corrosion include: Plated tin, Lead, Copper, Plated nickel. Corrosion is one of the major enemies of printed circuit boards. A sufficiently corroded circuit board won’t work, and the steady advance of corrosion is inevitable. In this passage we will focus on: why do printed circuit boards corrode, and what are some of the most common causes of PCB corrosion? If you want to order PCB product, please check and custom your order online. What are the types of PCB corrosion? The metal in your circuit boards can corrode in several ways, including: AtmosphericThis is the most standard type of corrosion. Metal is exposed to moisture, which contains oxygen, causing a reaction where the metal ions bond with the oxygen atoms and create an oxide. Copper experiences atmospheric corrosion very easily, which is not a problem for copper plumbing because corroded copper retains its mechanical properties. It does not, however, retain its electrical conductivity, so this is a big problem for circuit boards. GalvanicGalvanic corrosion occurs when different types of metals are in the presence of an electrolyte. In these circumstances, the more resistant metal will actually corrode faster than the baser metal it’s in contact with, so when gold is in contact with tin, for example, the gold will corrode much faster than usual. ElectrolyticIn this type of metal degradation, adjacent traces experience dendrite growth when ionic contaminated moisture infects the electrical voltage between them, creating metal slivers that result in a short circuit. FrettingWith fretting corrosion, the action of closing solder-plated switches creates a wiping action that removes the surface oxide layer, allowing the layer beneath to oxidize. Eventually, excessive rust builds up and prevents the switch from activating. How to clean corrosion PCB? If your PCB gets corroded from water damage or from another source, cleaning it may repair it. Cleaning a circuit board requires everyday household items that even small companies can afford. However, only someone with a fundamental knowledge of electronics should attempt to clean a PCB. The process involves disassembling the board and avoiding damaging the components. When you separate the PCB from an electronic, stay away from water and disconnect the device. You can use a variety of tools to clean a PCB, but certain items work best for eliminating corrosion. Cleaning a circuit board with corrosion involves the following materials: Baking sodaThe alkalinity and abrasive qualities of baking soda make it a perfect cleaner for corroded PCBs. It clears and neutralizes any corroded areas without damage. Deionized waterWhen you use water to clean a circuit board, you must make sure it has no contaminants. The ions in regular water have conductive properties that degrade electronics. Meanwhile, deionized water has no contaminants or ions that cause damage. Household cleanerA phosphate-free household cleaner can help you remove dirt and corrosion effectively. Phosphates protect PCBs from corroding, but they also act as a major source of water pollution. Thin, soft-bristle brushIf you do not have a specialized PCB cleaning tool, a toothbrush or paintbrush can also work. A brush with soft bristles will not scratch the board’s delicate components. Lint-free towelCloths made from microfiber and other lint-free fabrics speed up the drying process without leaving particles behind. OvenA simple household oven thoroughly dries a PCB when you use indirect heat. Never place a circuit board in the oven without ensuring the oven is off first, however.Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 06/04/2021 17:37
How to make FPGA PCB?
A field-programmable gate or grid array is a little more complicated than a microcontroller. Most of the time, a chip comes pre-programmed. As the user, you can change software, but not hardware. This brings us to the defining element of an FPGA — you, the user, can configure its hardware after purchase. Engineers find this especially useful for prototyping their own application-specific integrated circuits. In fact, Intel uses a form of FPGA to streamline their own prototyping process. FPGAs are also useful because the devices in which FPGAs are embedded can be altered without needing all-new hardware. Engineers find this especially useful for prototyping their own application-specific integrated circuits. And in this passage we will talk about all the details of FPGA PCB.If you want to order PCB product, please check and custom your order online.How does FPGA PCB work? FPGAs have an “array” of integrated hardware circuits — these arrays are groups of programmable logic blocks. During manufacturing, an FPGA has not been configured to have any particular function. Instead, the user can configure it and later reconfigure it however they choose. The user does this using a hardware description language (HDL). An FPGA has logic blocks, like AND and XOR, which the user can piece together with interconnects. Modern FPGAs have many logic gates and RAM blocks, so they can accommodate complex computations. Some FPGAs also have analog-to-digital converters or digital-to-analog converters, similar to field-programmable analog arrays (FPAAs). What are the features of FPGA? They require more skill to use: You’ll need more than a basic understanding of coding language to program an FPGA. In addition to knowledge of a coding language, you’ll need to be able to track mass amounts of variables. You’ll also need to understand a hardware description language. Designing and redesigning hardware is not a task for beginners. They allow for more parallelism: An FPGA has thousands of logic blocks, all of which you can program. You can create processes independent of one another, decreasing instances of bottlenecking as with microcontrollers. They allow for a higher level of customization: Simply put, if you know what you’re doing, you can do a lot more with an FPGA than a microcontroller. If you want to program something complicated, you’ll need more customizability than a microcontroller provides. They tend to cost more: One drawback of FPGAs is that they tend to be more expensive than microcontrollers. Despite higher upfront costs, they can save money for industries that may need to make retroactive changes — think of the rear-view camera example. They’re ideal for more complex applications: Because FPGAs allow for parallel processes, you can implement more inputs with an FPGA than with a microcontroller, without running into a bottlenecking issue. This makes them ideal for more complex operations. They allow for later alteration: One of the biggest benefits of an FPGA is that the hardware itself can be changed after its initial programming. For this reason, you can change a device’s function without completely replacing its hardware. This is more cost-effective in the long run, especially for mass-producing industries. How to make FPGA PCB? The normal steps I follow are: Find a COTs board and get a rough idea of the internal FPGA resources you will need, in particular I pay attention to: LUT (look up table) countUse this rule of thumb. If the design is nearly finished take the size of the design (LUT count) and find an FPGA with at least 30% more LUTs. if the design is not close to finished go up to 50% or 100% more LUTs. So if the design fits into 9K LUTs make sure to use an FPGA with 12K LUTs or greater. I tend to go overkill and probably would go up to 25K LUTs. This will save you excruciating headaches later. Whomever is commissioning this board design should understand that there should be more than one spin of this design so it is understandable to oversize the first version of the FPGA. There are a lot of available FPGAs that have different LUT counts in the same package size so for example the Xilinx Spartan 6 LX45 Package is the same as the LX75 so you can start out by using a the LX75 (75K LUTs) and if your design easily fits into less than 40K LUTs then you can save costs on the design with just a BOM Change. BRAM (Block RAM count)Determine if your design requires more memory resources than your FPGA has internally. This is easily overlooked at first but in a design you tend to use block RAM for various reasons (ROMs, FIFOs, etc...) I ran out of block memory on a design and attempted to use distributed RAM (using the LUTs as RAM) and it ate up all my LUTs very fast. It's important to determine if you will require external memory. This adds a lot of risk to designs because if the design requires any level of performance you can't just use an external SRAM or SDRAM as your memory because their data transfer rates from these components are terribly slow compared to the speed at which you can move data around in your FPGA so the only comparable way to move data is with DDR2 and DDR3 and if you have to use these you add risk due to mistakes in schematics and layout and more work for the HDL team. Enumerate all signaling standards and possible voltage levels your will use: This is important because some of the signaling standards you wish to use (LVDS, LVSPEC, LVCMOS) may have voltage restrictions. Go through the user guides and make sure all these standards are supported. Power supply requirementsI sympathize with all the previous gripes about undersized power supplies getting the core voltage spec'ed is tuff, lately I have been using a lot of TI Nano modules for the large but low end FPGAs (Spartan LX45(T) - LX75(T) and Lattice ECP3). Fortunately you can mitigate some of the risks on when sizing the power supplies used for the I/O. In particular if this bank is not driving an unknown source (expansion connector) then the process is as follows: Find all the components that this bank will attach to, determine the input capacitance for all of those components, find out the maximum clock rate you will be driving these signals then you can calculate both the power requirement and roughly estimate the bypass requirement, although a lot of the FPGA manufacturers have been putting on the minimum bypass capacitor requirements in something like the DC Switching Guidelines. Using the equation [P = (1/2)CV^2 * (f)] where C = input capacitance, f = frequency. of the input your FPGA must drive (For each signal!). you can find out worst case estimate on how much power is required to drive all output signals. You will also need to consider the power loss associated with internal termination resistors (based on the I/O standards you use)Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 06/04/2021 17:28
How to reduce heat on PCB？
In the PCB manufacturing process, the temperature inspection is really essential and it will influence the performance and finished products of PCB. And if we meet the high heat of PCB, how can we reduce the heat and check this passage we will tell you about all the detailed knowledge about it. If you want to order PCB product, please check and custom your order online. What are the causes of high heat of PCB? These are a few common causes of high heat in a PCB: 1. Component Malfunction Causing DissipationOne common cause of high heat in a PCB is that one component within the PCB malfunctions and dissipates, failing to generate the amount of power it typically produces. When this happens, the surrounding components have to generate more power to compensate. Generating more power leads to the risk of overheating. 2. Through-Hole InterferenceThrough-hole components and heat-sink components are the components of the PCB that supply power. They generate heat and dissipate it into the air. If a heat sink is soldered incorrectly, or if a different component of the PCB is interfering with the through-hole, the other components will generate more heat than usual to compensate. This scenario also leads to a risk of overheating. 3. Surface-Mount Device DistanceSurface-mount devices (SMDs) connect to the PCB in the same way through-hole components do. They allow for a smoother flow of current through the through-hole and heat-sink components. But the through-hole components and the SMDs must be positioned at the correct distance from one another. If they are too far away, the current will have farther to travel. The extra time it takes the current to travel can cause the receiving components stay cool for too long. When that happens, other components may overheat to compensate. 4. High-Frequency CircuitsHigh temperatures are particularly likely in applications that make use of high-frequency circuits. The reason is that the generation of more power naturally produces more heat. Radio-frequency circuits, for example, represent a fast-growing sector in PCB engineering. These circuits are highly complex but have many useful applications, from wireless security in medical and industrial products to smart phones. These high-frequency circuits tend to generate tremendous amounts of heat, so special design techniques are necessary for these types of PCBs. 5. Lead-Free SolderAs a whole, the PCB industry is moving toward the restriction of hazardous substances (RoHS). RoHS PCBs use lead-free solder, and lead-free solder requires high temperatures so it can flow freely. How to reduce heat on PCB？ As we have seen, preventing a PCB temperature rise is critical. But how can you reduce heat in a PCB? Engineers can employ a few different PCB heat dissipation techniques: 1. Heat SinksA PCB is basically a heat-generating factory because of all the heat-producing components it contains. The PCB needs some way to dissipate all that thermal energy. Generally, the answer involves heat sinks. Heat sinks dissipate the heat safely so it will not build up and damage the board. 2. FansMost electronic devices contain fans for cooling, and part of the purpose of those fans is to help cool PCBs. Cooling fans disperse heat out of electronic devices while letting cool air in, helping to prevent overheating and extend the PCB’s lifespan and performance. 3. Considering Materials and ComponentsChoosing heat-resistant materials is one of the most effective strategies for reducing heat in a PCB. For example, heavy copper PCBs constructed with thick copper plates make excellent choices for their durability and ability to withstand high temperatures. They handle higher levels of currents, resist higher temperatures for longer amounts of time and provide for stronger connection points than standard PCBs. For these reasons, they are particularly useful in automotive, aviation, heavy machinery and power converter applications and other heavy-duty environments. 4. Increasing Plate Thickness and WidthIn PCBs, thicker plates tend to conduct heat less effectively than thinner ones. They require more power to reach high temperatures, so with the right engineering, they can help reduce the risk of overheating, warping and disruption. 5. Applying LaminatesApplying laminates is another way to prevent damage from high temperatures. High-temperature PCB laminates can prevent overheating by offering heat protection for the PCB’s components. High-temperature laminates should have the following protective properties: Glass transition temperature (TG)Time to delaminationMoisture absorptionDecomposition temperature (TD)Z-axis expansion 6. Aligning CTEsThe coefficient of thermal expansion (CTE) measures how much a material expands when exposed to high temperatures. In PCB design, it’s ideal for the dielectric layers to have a similar CTE to that of the copper layers. That way, if the layers expand, they do so in a uniform way that leads to minimal damage. In a multilayer stack, if CTEs are not aligned, the layers will expand at radically different rates, which can cause warping and disruption. If this uneven expansion occurs during PCB assembly, the misalignments can also cause serious problems for drilling. Choosing PCB materials with lower CTEs helps prevent overheating. 7. Maintaining Adequate SpacingDetermining component spacing on a PCB can be a tricky process. When board components are too close together, crosstalk may result — that is, different components may begin interacting with each other in undesirable ways. These unwanted interactions lead to something known as the skin effect. When the skin effect occurs, trace resistances increase, leading to resistive losses and adding heat to the circuit. The skin effect is particularly common with high-frequency PCBs, so engineers must take extra care with component spacing to keep the boards from overheating. 8. Integrating Heat Pipes CorrectlyHeat pipes in a PCB can help disperse heat as well. The liquid in the pipes can absorb heat and prevent it from damaging the components of the board. 9. Maximizing RTI and MOTRelative thermal index (RTI) and maximum operating temperature (MOT) are two relevant measurements engineers should pay careful attention to in the design of PCBs. RTI indicates the highest temperature that a material can handle without undergoing changes to its properties or a reduction in its performance.Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 06/02/2021 17:41