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Who is a better PCB designer?

Posted by iFast PCB on June 16, 2016 in PCB Design, PCB News

A lot of feedbacks can be received regarding the design of the PCB. The circuit engineers and the PCB engineers comment very frequently regarding the frustration that is involved in working of both the members in consultation with each other. A very common question or a feeling that arises in most of the engineers is that whether electrical engineers are better PC board designers.

The subject that mainly deals with the designing of PC boards is arts. People feel that it is a matter of engineering but the main subject that is involved is Arts. Designing also requires the knowledge of science. The main area of science that is used is the manufacturing as well as assembling of the bare boards as well as the basic knowledge of mechanics. Electronics is not much required for the designing purpose. A person who has circuit theory knowledge cannot be a good board designer. Rather a person having the knowledge of pad to-hole ratio, value of copper balance, the impact of copper placement on assembling and repairing, as well as the knowledge of thermal transfer is considered to be a better board designer. Analytical ability is another major tool that is required for the proper designing of the boards. For a proper performance impact the standard that was followed in the past had very low frequency and the traces of boards used to be very long than the actual distribution length. But the standard that is followed today can contain mistake on the board and it is very likely that the working of the circuit will not be hampered. In many cases this assumption failed and in such cases knowledge of electronics is required.

The board designing methods in between the year 1950 and the late 1980 used the law of physics that implements the bending laws and this caused a lot of disaster in the designing structure. Many designers of that period till today struggle a lot in finding out the possible ways without taking any help from the engineers. The PC board designers of that period got converted to mechanical designers, artists or technicians and they have mastered the art of artwork tapping and also learned to read a schematic diagram. The main problem that is being faced in this period of time is that the electrical engineer counterparts and the board designers do not take each other’s help and completely ignore each other’s ideas and way of working.

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Six Tips for choosing PCB components

Posted by iFast PCB on June 15, 2016 in PCB Design, PCB Manufacturing, PCB News

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1. Consider the component package choice

Throughout the schematic drawing phase, we should consider making the decisions of the component package and pad patternin the layout stage. Here are some recommendations when selecting components according to component package.

Package includes electrical pad connection of components and mechanical dimensions (X, Y and Z),and namely the shape of element body and pins of the connection PCB .When selecting components,we need to consider any installation or packaging restrictions which may exist on the top and bottom layers of final PCB.

Some elements (such as polar capacitor) may have a clearance height restrictions,which need to be considered in the component selection process. In the very beginning the design,you can draw a basic board outline shape,then place large-scale or key lacation components which you plan to use,such as connectors.

In this way, you can quickly and visually see the virtual perspective of no wiring board ,and give the relative accurate circuit board and the relative positioning of components and component height.This will help ensure after pcb is mounted,the components can be suitably placed in the packaging,such as plastic products. Call three-dimensional preview mode from the Tools menu to browse the entire board.

Land pattern shows the actual pad and via shape of welding device on the PCB.These copper pattern on the PCB also contains some basic shape information.The right size of pad pattern can ensure the proper welding,and can ensure correct mechanical and thermal integrity of the connected elements .

In the PCB design  layout, we need to consider how to manufacture PCB, or when manual welding, how to weld the pad. Reflow (solder melted in a controlled high-temperature furnace) can handle a wide variety of surface-mount devices (SMD). Wave soldering is generally used to weld the opposite side of the circuit board, to fix the through-hole devices, but can also handle the table components which are placed in the back of PCB.

Typically when using this technique, the underlying surface mount components must be arranged in a specific direction, and in order to adapt to this welding, we may need to modify the pad.

Throughout the design process,we can change the selection of the element. Early in the design process,we should determine which devices should use plated through hole,and which should use the surface-mount technology (SMT),which is good for the overall planning of the PCB.We need consider the factors,such as device cost,availability, device area density and power consumption, and so on.

From a PCB manufacturing point of view, surface-mount devices are generally cheaper than the through-hole devices, and with higher availability. For small-scale prototype of the project,it is better to select larger surface-mount devices or through-hole devices .It is not only convenient for manual welding,but also facilitate troubleshooting ,and has better connection between pad and signals in debugging process.

If the database has no ready-made package, usually create a customized package in the tool.

2. Use a good grounding method

Ensure that the design has sufficient bypass capacitor and the ground plane. When using an integrated circuit,ensure that we use the appropriate decoupling capacitors at the position where is close to the supply terminal to ground. Suitable capacitance depends on the particular application, capacitive technology and operating frequency. When the bypass capacitors are placed between the power and ground pins,and close to the right IC pins, it can optimize electromagnetic compatibility and susceptibility of the circuit.

3. Assign the virtual device package

Print a bill of materials (BOM) ,which is used to check the virtual element. The virtual element has no relative package,and can not transfer to the layout phase. Create a list of materials, and then view all the virtual components.

The only entry should be the power and ground signals, because they are considered a virtual element. Only in the schematic environment,can they have specialized treatment,and will not be transferred to the layout.Except for the purpose of simulation, elements ,which are shown in the virtual part ,should be replaced with packaging components.

4. Make sure you have a complete bill of materials data

Check whether material bill report has enough data. After you create a bill of materials report, you should carefully examine,and complete the incomplete elements and vendor or manufacturer information.

5. Sort according to the component label

To help sort and view bill of materials, make sure the element label are consecutively numbered

6. Check the extra gate circuit

In general, input of all the extra gates should have signal connection, to avoid floating inputs,to make sure that you check out all excess or missing gates, and all inputs that are not connected are completely connected. In some cases, if the input is in a suspended state, the entire system does not work properly.

In some cases, IC,which have a suspension pin, may not work properly in the target range.Usually only when the IC device or other gates of the same device do not work in saturation-when the input or output is near or at element power rails,the IC can meet requirements when it works. Simulation usually can not capture this case,because simulation models generally can not make the portions of the IC connected together for modeling suspension connection effect.

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The introduction of Common PCB surface treatment

Posted by iFast PCB on June 15, 2016 in PCB Manufacturing, PCB News

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The most basic purpose of the surface treatment is to ensure good solderability or electrical properties.Because the copper in the air tend to exist in the form of oxides, it is unlikely to maintain the original copper for a long time,so copper require additional processing. Although in the subsequent assembly ,a strong flux can be used to remove oxide of most copper,but flux itself is difficult to remove,so the industry generally do not use strong flux.There are many PCB surface treatment.The common treatments have hot air leveling (HASL), organic coating (OSP), electroless nickel / immersion gold (ENIG), immersion silver and immersion tin.The following will be introduced one by one.

1. The hot air leveling (HASL)

The hot air leveling is also called hot air solder leveling.It is the technology that coat the PCB surface with molten tin-lead solder and heat the compressed air to blow leveling,to form a coating layer that prevents the copper from being oxidated,but also provides good solderability.When in HAL,solder and copper form copper-tin intermetallic at the junction.The thickness of solder that protect the copper surface is about 7 ~ 11μm.When in HAL,PCB need to be immersed in molten solder. Air knife blow leveling the solder before solidification of the solder ;Air knife can make the crescent-shaped solder on the copper surface minimize and prevent solder bridging.

HASL is divided into two kinds of vertical and horizontal. It is generally believed that horizontal is better, mainly because the coating of horizontal HASL is more uniform ,and can be achieved automated production. Thickness of HASL solder and flatness of pad is difficult to control,and it is difficult to mount a narrow pitch components. Lead-Free HASL:it replaces Pb-Sn with non-Pb-Sn metal or lead-free solder alloys.

The general process of hot air leveling process is :micro-corrosion→preheating →coating flux→spray tin-cleaning.

2. Organic coating (OSP)

Organic coating process is different from other surface treatment processes.It is to act as a barrier layer between the copper and air. Organic coating process is simple, low cost, which makes it possible to widely be used in the industry.Molecular of early organic coating is imidazole and benzotriazole with the role of rust protection.The latest molecular is mainly benzimidazole.In the subsequent soldering process,if surface of copper has only one organic coating layer,that is not OK.It must be a lot of layers.

This is why you usually need to add copper solution into a chemical bath. After the first layer of the coating, the coating layer adsorbs copper;then organic coating molecules of the second layer combine copper.Until twenty or even a hundred times ,organic coating molecules assemble in the copper surface,which can ensure many times reflow soldering. Test showed that: the latest organic coating process can maintain good performance in a number of lead-free soldering process.

The general process of organic coating process is as follows: degreasing → micro etching→ acid washing→ water washing→the organic coating→ washing.Process control is relatively easier for other surface treatment processes

3. electroless nickel / immersion gold (ENIG)

Electroless Nickel / Immersion Gold Process is not as simple as organic coating.Electroless nickel / immersion gold seems to give PCB to wear thick armor. Additionally, electroless nickel / immersion gold process is unlike organic coating as rust-proof barrier,and it can be useful and has good electrical properties in long-term use of PCB.Therefore, electroless nickel / immersion gold wraps a thick layer of nickel-gold alloy with good electrical properties on copper surface, which can protect PCB for a long time. In addition,it also has the patience for the environment that other surface treatment processes do not have.

The reason of plating nickel is due to interdiffusion between gold and copper, and the nickel layer can prevent the spread between gold and copper; if there is no layer of nickel, gold will spread into the copper in a few hours.Another benefit of Electroless Nickel / Immersion Gold is the strength of nickel. Nickel of only 5 microns thick can limit expansion at high temperature in the Z direction. In addition electroless nickel / immersion gold can also prevent dissolution of copper, which will benefit the lead-free assembly.

The general process of Electroless Nickel / Immersion Gold Process is: acid cleaning →micro-corrosion→prepreg → activation →Electroless Nickel →Immersion Gold. There are six chemical tank, involving nearly 100 chemicals, so process control is relatively difficult.

4. Immersion Silver

Immersion silver process is between the organic coating and electroless nickel / immersion gold .The process is relatively simple and fast;It is not as electroless nickel / immersion gold as complicated,and it also does not give PCB to wear thick armor,but it still can provide good electrical performance. Silver is little brother of gold. Even if when exposed to heat, humidity and pollution of the environment,the silver is still able to maintain good weldability, but will lose their luster.Immersion Silver does not have good physical strength of electroless nickel / immersion gold because silver below has no nickel layer .

Immersion Silver is a substitution reaction.It is almost submicron pure silver coating.Sometimes immersion silver process also contains some organic matter, mainly to prevent the corrosion of silver and eliminate silver sigration. It is generally difficult to measure out a thin layer of organic matter. The analysis showed weight of the organism is less than 1%.

5. Immersion Tin

Since all current solders are tin-based, so the tin layer can be matched with any type of solder phase. From this point of view, immersion tin process extremely has development prospects. But previous PCB appears tin whisker after immersion tin process.Migration of tin whisker and tin bring reliability problems in the welding.So the use of immersion tin process is limited. Later, immersion tin solution was added to the organic additives,which make tin layer structure granular structure, to overcome the previous problems,but also has good thermal stability and weldability.

Immersion tin process can form a flat copper-tin intermetallic compound,and this feature makes the immersion tin have good weldability as hot air leveling and without flatness problem as hot air leveling.Immersion tin has no diffusion problems between metal of electroless nickel / immersion gold——copper-tin intermetallic compound can bind together firmly.Immersion tin board can not be stored for too long.When assembly, it must be carried out according to the order of immersion tin.

So, when we do a product, how to choose suitable surface treatment of it? Surface treatment choice depends on the type of final assembly of components; surface treatment will affect the PCB manufacturing, assembly and final use, the following describes usage scenarios of five common surface treatment process.

1, hot air leveling

HASL had a dominant position in the surface treatment process of PCB manufacturing. 1980s, more than three-quarters of PCB use hot air leveling process, but in the past decade PCB industy is aways reducing the use of hot air leveling process. It is estimated there are about 25% -40% of the PCB using a hot air leveling technology.Hot air leveling process is dirty, smelly, dangerous, and therefore it is never pleasing process, but for larger size components and larger spacing wire , it is an excellent process.

In the higher density PCB board, HASL flatness will affect subsequent assembly; so HDI PCB boards generally do not use hot air leveling process. As technology advances, the industry has appeared hot air leveling process used for QFP and BGA of smaller assembly pitch,but practical use is less. At present, some factories use organic coating and electroless nickel / immersion gold process to replace the hot air leveling process; technological development also makes a number of factories use immersion tin and immersion silver process. Together with the recent trend of lead-free, hot air leveling use is further limited. Although there have been so-called lead-free HASL, but it may be related to compatibility issues with the device.

2. Organic coating

Estimated that about 25% -30% of the PCB use an organic coating process, and the ratio has been rising (probably organic coating now has exceeded hot air leveling living to rank the first). The organic coating process can be used in low-tech PCB,and can also be used in high-tech PCB, such as single-sided PCB of television sets, board of high-density chip package . For BGA aspect, organic coating applications is greater. If pcb has no requirement of surface connection function or storage period,the organic coating is the ideal surface treatment process, but because the OSP film itself is insulated,when you choose this surface treatment,you need to handle the ICT test points better.

3. Electroless Nickel / Immersion Gold
Electroless nickel / immersion gold process is different from organic coating.It is mainly used the board whose surface has the requirement of connection function and has a longer shelf life,such as the phone keypad, the edge connection area of router,electrical property connection area of elastic connection of chip processor.Because of the flatness problems of hot air leveling and removing problems of organic coating flux, in the 1990s electroless nickel / immersion gold is widely used; Later, because nickel-phosphorus alloy appear,applications of Electroless nickel / immersion gold process have reduced.But at the moment almost every high-tech PCB plant has electroless nickel / immersion gold line.Considering the solder joints will become brittle when removing copper-tin intermetallic compound.The relatively brittle nickle-tin intermetallic compound will appear a lot of issues.

Therefore, the portable electronic products (such as mobile phones) almost use copper-tin intermetallic compound solder joint which is formed by organic coating,immersion silver and immersion tin,while use electroless nickel / immersion gold to form a keypad, the contact area and EMI shielding areas .It is estimated that about 10% -20% of the PCB use electroless nickel / immersion gold process.

4. Immersion Silver

Immersion silver is cheaper than electroless nickel / immersion gold. If the PCB has connectivity requirements and need to reduce costs, immersion silver is a good choice; plus the good flatness and contact of immersion silver,it should be better to choose immersion silver process. In communications, automotive, computer peripherals, applications of immersion silver are many.In high-speed signal design immersion silver has been applied. Because immersion silver has good electrical properties that other surface treatment can not match.It can also be used in high-frequency signal.

EMS recommend to use immersion silver process because it is easy to assemble and has better checking . However, the defects of immersion silver ,such as tarnish and solder voids,make it grow slowly,but not decrease. Furthermore, since silver is very sensitive to sulfur,if the product application environment has rich sulfure element,you should choose carefully. It is estimated that about 10% -15% of the PCB use immersion silver process.

5.Immersion tin

That tin is introduced into the surface treatment process is nearly a decade of thing.The appearance of this process is the result of automation requirements.Immersion tin does not bring any new element in the soldering welding,and it is especially for communication backplane.Out of the storage period of the board,tin will lose weldability,so immersion tin need better storage conditions.In addition,immersion tin process contains carcinogenic substances,so it is restricted.It is estimated that about 5% -10% of the PCB use the immersion tin process.

With the rising demand of customers, the increasingly stringent requirements of environment,surface treatment process more and more, in the end choosing the kind of promising, more versatile surface treatment process, it seems like a bit confusion. Where will PCB surface treatment process go in the future,and now it is not able to accurately predict. In any case, meeting customer requirements and the protection of the environment must be done!

We must choose the surface treatmetn according to the practical needs of products, for example:
Printed circuit board with double-sided mount and mixed-sided mount use immersion silver.If you are using OSP, you may use nitrogen or small corrosive flux during reflow and wave soldering.You have the flexibility according to the product.If you use ENIG,nitrogen does not need to be used. In the choice of the surface plated layer, the use of nitrogen,the type of flux, and the sensitivity of the cost , these are important factors. In short, the selection of lead-free PCB pads coating layer must consider the compatibility among solder,process and PCB pad coating.

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92ML – A new PCB material offering high power solution

Posted by iFast PCB on June 13, 2016 in PCB Manufacturing, PCB News

A new PCB material named 92ML has been introduced. This material is enhanced thermally and has been specifically manufactured and engineered for meeting the high power PCB application demands. Some of the advantages of the 92ML materials are the laminate systems are thermally conductive and based on epoxy, the 92Ml material is flame retardant as well as halogen free. A low cost system that is lead free solder compatible is also provided by the companies. The system is also capable of enhancing heat transfer capacity. The materials that are incorporated with the above mentioned characteristic are ideal for applications that have multilayer and that require thermal management of the entire board.

Up to 4oz copper cladding is being provided with the laminate material named 92ML. This thickness level is enough for meeting the requirements of the power distribution. The material also has high thermal conductivity that is up to 3.5 W/mK. This system is also familiar with the epoxy based system which is the most important specification that makes this system ideal for the PCB used in the applications such as the power supplies, automotive electronics, motor controllers as well as convertors. The materials also have a very high Tg value of about 160 degree Celsius and is also combined with coefficient of low Z axis of the thermal expansion in between 175 ppm per degree Celsius and 22 ppm per degree Celsius. This low coefficient of Z axis of the 92ML material can survive the soldier exposure that is free of lead and also ensures reliability testing of the high TG PCB boards. The 92ML laminates also have rheological characteristics that enable a very high degree of flow of resin. This element is very critical element of the high power printed circuit boards manufacturing that is multilayer in nature.

This 92ML laminates are also available in combination with the plates of aluminium that forms an insulated metal substrate. This configuration of this material is such that it has an integrated heat sink that can be worked as a machine that can serve as a chassis that is mechanical in nature. It is also characterised to have a very high level of adhesion that is thermally stable in nature to the substrate of aluminium pcb. This material of laminate can withstand solder exposure of about 288 degree Celsius for over than seven minutes. This time limit is sufficient for assembling of the final product without any issues. This material is also very useful in areas that have a very high operating temperature as well as very high power. The areas of applications include automotive lighting, LED modules and power devices.

The PCB manufacturers offering these high-tech PCB products are leader of global technologies that are engineered to offer protection, power and connection with the world. The companiesdeliver high-performance solutions that are used for enabling clean energy, advanced transportation, Internet connectivity, and other critical technologies.

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Metal core technology for increasing the performance of LED products

Posted by iFast PCB on June 13, 2016 in PCB Manufacturing, PCB News

A new specialized technology (metal core pcb) has been developed for improving the performance of the LED product. This technology is known as the metal core pcb technology. The working formula of this technology is providing direct contact between the aluminium substrate and the metal core product. This technology has been developed because of increasing the performance capability of the LED product. This has been one of the main aims of many businesses working in this field. The main challenge that has been faced is the demand of customers to get aluminium plated with copper. Many permutations and combinations have been done for preparing and treatment of the surface. Finally a good bond was created from the copper plating that helped in giving direct thermal contact to the LED product. The LENZ drill route is coupled with this system for accurately milling out and also for getting an in depth knowledge. The main motive of every company should be to keep up to the desire of the customers and trying to add the requirement in the list of capabilities of the business.

A number of companies are working to get high quality, highly reliable, fast turnarounds PCB (printed circuit boards). Some of the other technologies that are also included in the list of high technological capabilities include sequential lamination, back drilling, hybrid dielectric packages, thin capacitance layer, high speed RF package, metal core pcb production, BBV’s and micro via technology and Epoxy and silver filled Via in pad. The main commitment of these companies is to provide the customers PCB solutions that are fastest and cheapest. The quotes are provided in less than four hours, fabrication is done within twelve hours to ten days and the standard lead time is of ten days.

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Flex PCB Drivers, Benefits and Applications (4)

Posted by iFast PCB on June 13, 2016 in Flex PCB

THREE-DIMENSIONAL AFFILIATIONS AND PACKAGING

A lot has been written over the years proclaiming the advantages of 3D interconnection structures. In recent times there has been a rise in intriguing 3D IC packaging approaches for system-in-package gadgets and now even the piling of semi- conductor wafers.

In earlier times, 3D affiliation was likewise of interest, as well as the benefits of shot molded boards to develop 3D interconnection structures has actually been talked about because the late 1970s. With flex PCB, the benefits of 3D affiliation are all-natural and innate attributes of the substrate. The truth is that some built board innovations employ flex circuits intheir procedures by inserting them right into the mold and mildew before plastic injection.

AIRFLOW AND THERMAL MANAGEMENT IMPROVEMENT

The uniform planar nature of flexible circuits boosts the flow of cooling air through a digital box. The massive bundles of wire that they typically replace usually function as obstacles

to excellent air blood circulation inside an electronics assembly container.

CERTIFIED SUBSTRATE FOR SURFACE MOUNTING

Surface area mount modern technology experienced numerous troubles in its early years. A significant factor was the inequality be- tween the coefficients of thermal development of the board as well as the element. This inequality resulted in solder joint tension, which was the reason for many early failures in digital assemblies.

While product scientists and developers have actually since corrected the majority of the issues with far better design practices, one technique that functioned well was the use of flex PCB base materials that are normally certified and also therefore present less anxiety on the solder joints of gadgets placed on the circuit surface area.

EVEN MORE ENGINEERED PRODUCT LOOK

This could be considered a trivial worry by some, the inner look of a digital package can have a refined impact on a possible individual’s decision-making process. This is particularly the case if the individual is currently familiar with the many benefits of flex PCB. Truthfully, the “mass of pastas” represented by some cord harness building and construction commonly looks hopelessly messy.

Cable harnesses have a long background in a large variety of large system structures. Mainly they have actually been utilized for electrical power distribution for illumination, ignition as well as such. They are additionally well-suited to use in lots of complex systems such as “zip cable” airplane and also progressively intricate vehicle electronics. Nonetheless, in smaller product applications, flex PCB could verify to be not just more cost effective, however might also supply the engineered appearance that may serve as a subtle sales factor.

BETTER SIGNAL INTEGRITY

With the basic fad toward greater speed digital signaling in electronic systems, signal stability is an important matter as well as flex PCB are ideally fit to the activity. This benefit reinforces the flexibility of flexible circuits about the needs in the current industry.

In practice, broadband requires fast increase times and any kind of- everything that breaks down the ideally square wave pulse signal have to be handled. In this respect, dielectric consistent and also loss tangent of products become of better problem than conductor loss. In response, some outstanding flexible circuit materials have been created that will be gone over in even more detail later.

Since usual design capabilities could break down signal integrity, design strategy is vital. Therefore, some designers have actually chosen some uncommon constructions. An example is a transposed set building developed making use of flex circuits to approximate twisted set building and constructions.

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Flex PCB Drivers, Benefits and Applications (3)

Posted by iFast PCB on June 13, 2016 in Flex PCB

POINT-TO-POINT WIRE REPLACEMENT

A longstanding general rule used in the flex circuit neighborhood was that a flex circuit should be made use of when more than 25 point-to-point wires were needed. The number was some- just what arbitrary, but the underlying principle is still essential. It is, however, worth a minute to think about if flexible circuits are a viable alternate no matter wire matter. As a part of the calculus, the use of flex PCB have to be examined taking into consideration the cost, application, item volume and other variables. Some item developers have found flex PCB to be a lot more cost-effective, or otherwise preferable, with as few as 2 or three cables. Still, some applications are most ideal served by cord harness innovation and force-fitting flex right into these applications is not suggested. Number 3-2 shows an example where a wire harness is clearly a better selection.

DYNAMIC FLEXURE OF THE CIRCUITRY

Dynamically flexing a circuit is one of the much more commonly pursued applications for flex PCB. While other interconnection solutions, such as flat bow cable television, have served the same purpose as vibrant flexing in some applications, flex PCBs have actually verified remarkable as a conventional technique of making reputable affiliations in between relocating components. The slimness of base materials, combined with the ability to utilize quite slim copper aluminum foil, make flexible circuits the most effective selection for vibrant flexing applications.

CONTROLLED IMPEDANCE SIGNAL TRANSMISSION

Numerous base materials utilized in the manufacture of flexible circuits have awesome inherent electric as well as mechanical residential properties. Uniformity of thickness as well as electric buildings are key to signal transmission line development. Because of this, it is reasonably easy to produce flex PCBs appropriate for high- rate transmission line cord applications. With such uniform materials, the only requirement of the flexible circuit manufacturer is to accurately engrave the copper aluminum foil to achieve the desired characteristic resistance. Flex circuits are a great choice for the commonly-selected value of 50ohm microstrip structure. Greater characteristic resistance styles and also stripline structures tend to understand rather thick in their building and construction and also lose some of their flexibility. To eliminate this trouble, it is essential to make the signal line sizes of the transmission line cable quite tiny, which could reduce total manufacturability due to reliability limitations. Fortunately, for high-speed signaling, conductor loss is less of a worry. The dielectric homes of the circuit materials are beneficial due to the fact that the signal propagates from the polymer instead of with the conductor, a sensation called the skin result. One caution is that some flexible circuit products soak up more dampness compared to others, leading to the alteration of the loss tangent.

BOOSTED HEAT DISSIPATION CAPABILITY

Level conductors have a much higher surface area to quantity proportion compared to round cord. The added area assists in the dissipation of warm from the circuit. When as compared to rigid board building and constructions, not just is the thermal course for flex PCB constructions shorter, however warm can be efficiently dissipated from both sides of the circuit because of its thinness. There are also base materials that are packed with not natural products, such as ceramics, that could enhance warm dissipation. They will also alter the dielectric residential properties. In comparison to a flex circuit, a regular one- or two-layer stiff board has a dielectric substratum that is a thermal insulator, hindering the circulation of heat with the circuit. Nevertheless, stiff PCBs with very heavy copper innerlayers or metal cores can additionally be highly effective at dissipating warmth.

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Flex PCB Drivers, Benefits and Applications (2)

Posted by iFast PCB on June 13, 2016 in Flex PCB

There are several needs to utilize Flex PCB and also benefits that can be delivered by using them making the interconnections in an electronic package. In some cases, such as dynamic bending applications, the choice to make use of flexible circuits is an obvious one, drivinged a car strictly by the absence of feasible choices.

There are numerous even more refined locations of opportunity to use flexible circuits, as well as this has actually proven to be the genuine action of their success. The taking are some locations where flex circuits have actually fixed challenging packing problems.

REDUCTION IN PACKAGE SIZE

Flex PCB use the thinnest dielectric substrates offered today making digital interconnections. In many cases, it is possible to generate flexible circuits with a total density of less than 50µm (0.002″), including a safety coverlayer. As a factor of referral, rigid material counterparts could be two times as thick and usually lack the durability afforded by flexible base product substrates. While thinness is attractive, it is the formability of the flex circuit that enables a plan size decrease, and also stiff products might be an ideal option if planar density is the only factor that matters.

DECREASE IN PACKAGE WEIGHT

A side advantage of thinness is minimized weight. Since they do not employ encouragements that are classically higher in thickness compared to unfilled polymers, Flex PCB materials could be extremely lightweight. The outcome is that making use of Flex PCB can minimize the weight of a digital package significantly. For example, weight decrease of around 75% or more is feasible depending upon the specific nature of interconnection technology that is being replaced.

Minimized weight is among the major factors flex circuits have actually continued to be so prominent in aerospace applications throughout the years. It is additionally an eye-catching feature in portable electronics, where size as well as weight are evaluated along with performance and also look.

REDUCTION IN ASSEMBLY TIME

Flex PCB technology has the inherent capability to seamlessly incorporate the type, fit and function of a design into a solitary circuit. Due to this all-natural advantage, flexible circuits can significantly reduce an item’s assembly time. This capability is especially obvious when point-to-point electrical wiring is a need as a part of the last assembly process. While point-to-point electrical wiring is not a typically made in-process action, engineering adjustment orders are usually done in just such a way, and also flexible circuits can considerably enhance the 2nd procedure assembly process.

ASSEMBLY COST REDUCTION

With the reduction in assembly time comes a decrease in assembly expense, making it clear that Flex PCB  ought to have a substantial influence on assembly price compared with various other methods, depending upon the application.

Expense reduction is a natural result of flex innovation’s capability to reduce the variety of assembly operations called for as well as the

capacity of users to create and also check the circuit totally prior to dedicating the circuit to assembly. This is particularly true of cable harness replacement applications.

ASSEMBLY ERROR REDUCTION

While there could be mistakes in design, a flexible circuit could- not generate the sort of errors that a person can. Hu- man error in hand assembly is a consistent danger. Hand-built wire harness assembly is a particularly at risk process. An im- portant attribute of flexible circuit modern technology is that design functions are managed by the design itself. As a result, with the exception of errors due to out-of-control processes in manufac- turing, it is not feasible to path circuits to factors other than those assigned by the circuit design.

ENHANCED SYSTEM RELIABILITY

Reliability developers have always been quick to point out that when a digital package of any type of kind fails, it commonly falls short at a factor of affiliation. Frequently, those factors of failing are solder joint affiliations. Flex PCB are preferably designed to reduce the levels of affiliation. In the following articles of Assembly Processes for Flex PCB, a method called the Occam Process is explained, which can entirely remove solder interconnections. When a flexible circuit is correctly developed and put on a digital packing trouble, it should enhance integrity by reducing the number of degrees of affiliation required within an electronic bundle or assembly, even if soldering is required.

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Flex PCB Drivers, Benefits and Applications (1)

Posted by iFast PCB on June 13, 2016 in Flex PCB, PCB News

INTRODUCTION

Diversity is a trademark of flexible circuits and also they are as varied in their application as they remain in their design. Flex PCB have, for long right into the past and also proceeding today, offered in a variety of demanding applications. As an affiliation technique, they are unparalleled in terms of their versatility. The pattern is anticipated to proceed as an increasing number of developers end up being familiar with flex circuit technology’s lots of advantages.
The transformative path of Flex PCB modern technology has actually not been without challenges, and numerous very early customers suffered problems. The very first customers of flexible circuits experienced problems as well as failings due to a mix of variables. As an example, early flex materials did not meet the same criteria these days. Enhancement- ally, customers did not have a basic understanding of the capabilities and limitations of the technology in regards to the item design and/or the design policies that had to be followed to make sure success. With each other, these elements made the development path rocky for some individuals. For us today, Flex PCB innovation endured its infancy to end up being the vitally essential option it is today in the arena of digital product packaging modern technologies.
According to Prismark Partners, equally as this 4th edition of Flex PCB Technology prepares to go to press in 2011, the largest application market for Flex PCB is presents at a 28% share, complied with by computers at 27%, communications at 20%, consumer electronic devices 12%, automotive 5%, industrial/medical 4%, armed forces flex 3% and also the final 1%, incorporated circuit (IC) packing applications. Display screens are a crossover application and also are represented in almost each of the more frequently pointed out applications and markets determined in table 3-1.
The table provides a little tasting of products in the diverse electronics market that have been efficiently offered by as well as benefited from flexible circuits as well as gives an indication of merely exactly how extensively Flex PCB modern technology is being made use of to address electronic packing problems.

Automotive

  • Instrument panels
  • Underhood controls
  • Headliner circuits
  • ABS systems

Computers & Peripherals

  • Dot matrix print heads
  • Disk drives
  • Ink jet print heads
  • Printer head cables

Consumer

  • Digital & video cameras
  • Personal entertainment
  • Exercise monitors
  • Hand-held calculators

Industrial Controls

  • Laser measuring
  • Inductor coil pickups
  • Copy machines
  • Heater coils

Medical

  • Hearing aids
  • Heart pacemakers
  • Defibrillators
  • Ultrasound probe heads

Instruments

  • NMR analyzers
  • X-ray equipment
  • Particle counters
  • Infrared analyzers

Telecom

  • Cell phones
  • High speed cables
  • Base stations
  • Smart cards & RFID

Military & Aerospace

  • Satellites
  • Instrumentation panels
  • Plasma displays
  • Radar systems
  • Jet engine controls
  • Night vision systems
  • Smart weapons
  • Laser gyroscopes
  • Torpedoes
  • Electronic shielding
  • Radio communications

• Surveillance systems

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The connection mode between the PCB components

Posted by iFast PCB on June 10, 2016 in PCB Design

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The connection arrangement mode between PCB components.

(1) The printed circuit does not allow to have the cross circuit.For possible cross line,two kinds of solutions :”through” and “around” can be used. That is, let the lead go through from a gap at the foot of the other resistors, capacitors, transistors,or go around from one end of possible cross line.If the circuit is very complicated in exceptional circumstances, in order to simplify the design , jumper wire is allowed, which can solve the problem of cross circuit.

(2) Components,such as resistors, diodes, capacitors and so on,have two installation methods:”vertical” and “horizontal”.Vertical refers to that components are perpendicular to the printed circuit board for the mounting and welding,and its advantage is to save space. Horizontal refers to that components are parallel to and close to the circuit board for mounting and welding.It has the advantage of better mechanical strength of component mounting.These two different installation of components,their element pitch on the printed circuit board is not the same.

(3) A circuit ground point with the same level should be as close as possible.And the power supply filter capacitor of this level should also be on this ground point.In particular, the ground point of base and emitter of this level’s transistor can not be too far away,or the too long copper between the two ground points will cause the interference and the self-excitation.Using this circuit with such “point ground method,”the work is more stable,and it is not easily self-excitation.

(4) Total ground must be in strict arrangement principle with the high frequency – the intermediate frequency – the low frequency .Repetitious random access is not allowed.Wiring would rather be long between levels,we also should comply with this provision.Especially the requirement of the ground wire arrangement of frequency head, playback head, FM head is more stringent. If it is inappropriate,it will produce self-excitation which lead to the failure to work. Frequency circuit ,such as FM lead, often use the large wraparound ground,to ensure good shielding effect

(5) Strong current lead ,such as common ground, amplifier power leads, etc. should be as wide as possible,in order to reduce wiring resistance and voltage,which can reduce the parasitic coupling that may generate the self-excitation.

(6) High impedance traces should be as short as possible. Low impedance traces can be longer, because the high impedance traces are easy to get the line pipe and absorb the signals,which cause the circuit instability.Power lines, ground, base of no feedback element, and emitter lead belong to low-impedance traces. Emitter follower base alignment and the ground of two channels of tape recorders must be separated into their own way until the end of the effect and then together.If two-way ground wire does not separate,it is easy to produce crosstalk and decrease the separation.

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