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Component Testing Electronic Components Semiconductor Technology

Resins and coatings for electronic components

Coating components

Printed circuit boards (PCBs) are the core of many electronic devices and contain electronic components like capacitors, transistors and fuses. As such, keeping them safe and protecting them from damage is key to the continued working of electronic devices. Resins and conformal coatings can be used for this purpose.

Resins

Resins are the more sturdy, heavier option in terms of coatings. This is a great choice when protecting a PCB from adverse conditions and insulating it from potential physical damage.

Within the range of resins used, there are three main types that are used, with each suited to certain PCBs.

Epoxy resins

This compound is well-suited for potting electronics, and protects components against moisture and mechanical damage coming from vibrations or shocks.

Depending on if there are amines (curing agent) mixed with the resin the curing time of the PCB can differ. Something to watch out for is the exothermic reaction cause by the curing. Although this can be mitigated, there is a risk of damaging the component.

Polyurethane resins

The pricier cousin of epoxy resin, polyurethane can also protect PCBs against moisture, as well as high temperatures and UV. Most resins have a maximum temperature tolerance of 130⁰C.  However, polyurethane can cope with temperatures of up to 150⁰C if formulated well.

This maximum temperature is in part thanks to the resin having a lower exothermic rate compared to epoxy. Polyurethane is also more flexible, so is favoured when it comes to potting delicate components.

Silicon resins

Silicon also protects against UV light, and so is often used in LED applications where the change in the colour of the LED needs to be minimised.

Silicon is the most expensive of the three but is not as popular as its counterparts. The material thrives when it comes to high operating temperatures and heat-sensitive components, thanks to its low exothermic temperature.

Conformal coatings

While resins are thick, durable and designed for high levels of stress, conformal coatings are thinner, lighter and are transparent.

Thanks to the tiny layer of coating, usually applied with a paint brush or spray, this kind of coating is a lower-risk alternative than a heavy resin for fragile components.

The coating can be altered or removed more easily than the resin too, and the curing time is massively reduced. However, alongside this the component is more exposed and has a lower level of protection. This makes these coatings more useful for PCBs that will face shorter exposures.

Do your own research

Any coating of a PCB should be carefully considered depending on the purpose of the circuit board, the conditions and stresses it will face, and whether it already has a coating on it. If this is the case, chances are this original coating was meant as the PCB’s primary layer of protection.

Speaking of protection, Cyclops quality checks all of the electronic components it supplies. This protects its customers from damaged parts and counterfeits. For an extra layer of protection in your electronic component supply chain, contact Cyclops today.

This blog post is designed to be informative and is in no way offering advice or guidance on how to coat electronic components.

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Electronic Components Transistors

How transistors replaced vacuum tubes

Electronics has come on leaps and bounds in the last 100 years and one of the most notable changes is the size of components. At the turn of the last century mechanical components were slowly being switched out for electrical ones, and an example of this switch was the vacuum tube.

A lightbulb moment

Vacuum tubes were invented in the early 1900s, and the first ones were relatively simple devices containing only an anode and a cathode. The two electrodes are inside a sealed glass or aluminium tube, then the gas inside would be removed to create a vacuum. This allowed electrons to pass between the two electrodes, working as a switch in the circuit.

Original vacuum tubes were quite large and resembled a lightbulb in appearance. They signalled a big change in computer development, as a purely electronic device replaced the previously used mechanical relays.

Aside being utilised in the field of computing, vacuum tubes were additionally used for radios, TVs, telephones, and radar equipment.

The burnout

Apart from resembling a bulb, the tubes also shared the slightly more undesirable traits. They would produce a lot of heat, which would cause the filaments to burn out and the whole component would need to be replaced.

This is because the gadget worked on a principle called thermionic emission, which needed heat to let an electrical reaction take place. Turns out having a component that might melt the rest of your circuit wasn’t the most effective approach.

The transition

Transistors came along just over 40 years later, and the vacuum tubes were slowly replaced with the solid-state alternative.

The solid-state device, so named because the electric current flows through solid semiconductor crystals instead of in a vacuum like its predecessor, could be made much smaller and did not overheat. The electronic component also acted as a switch or amplifier, so the bright star of the vacuum tube gradually burned out.

Sounds like success

Vacuum tubes are still around and have found a niche consumer base in audiophiles and hi-fi fanatics. Many amplifiers use the tubes in place of solid-state devices, and the devices have a dedicated following within the stereo community.

Although some of the materials that went into the original tubes have been replaced, mostly for safety reasons, old tubes classed as New Old Stock (NOS) are still sold and some musicians still prefer these. Despite this, modernised tubes are relatively popular and have all the familiar loveable features, like a tendency to overheat.

Don’t operate in a vacuum

Transistors are used in almost every single electronic product out there. Cyclops have a huge selection of transistors and other day-to-day and obsolete components. Inquire today to find what you’re looking for at sales@cyclops-electronics.com, or use the rapid enquiry form on our website.

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Active Components Electronic Components Semiconductor Technology Transistors

The History of Transistors

Transistors are a vital, ubiquitous electronic component. Their main function is to switch or amplify the electrical current in a circuit, and a modern device like a smartphone can contain between 2 and 4 billion transistors.

So that’s some modern context, but have you ever wondered when the transistor was invented? Or what it looked like?

Pre-transistor technology

Going way back to when Ohm’s Law was first discovered in 1820s, people had been aware of circuits and the flow of current. As an extension of this, there was an awareness of conductors.

Following on from this, semiconductors accompanied the birth of the AC-DC (alternating current – direct current) conversion device, the rectifier, in 1874.

Two patents were filed in the 20s and 30s for devices that would have been transistors if they had ever reached past the theoretical stage. In 1925 Julius Lilienfeld of Austria-Hungary filed a patent, but did not end up releasing any papers regarding his research on the field-effect transistor, and so his discoveries were ignored.

Again, in 1934 German physicist Oskar Heil’s patent was on a device that, by applying an electrical field, could control the current in a circuit. With only theoretical ideas, this also did not become the first field effect transistor.

The invention of transistors

The official invention of a working transistor was in 1947, and the device was announced a year later in 1948. The inventors were three physicists working at Bell Telephone Laboratories in New Jersey, USA. William Shockley, John Bardeen and Walter Brattain were part of a semiconductor research subgroup working out of the labs.

One of the first attempts they made at a transistor was Shockley’s semiconductor triode, which was made up of three electrodes, an emitter, a collector and a large low-resistance contact placed on a block of germanium. However, the semiconductor surface trapped electrons, which blocked the main channel from the effect of the external field.

Despite this initial idea not working out, the issue was solved in 1946. After spending some time looking into three-layer structures featuring a reversed and forward-biased junction, they returned to their project on field-effect devices in a year later in 1947. At the end of that year, they found that with two very close contact junctions, with one forward biased and one reverse biased, there would be a slight gain.

The first working transistor featured a strip of gold over a triangle of plastic, finely cut with a razor at the tip to create two contact points with a hair’s breadth between them and placed on top of a block of germanium.

The device was announced in June of 1948 as the transistor – a mix of the words ‘transconductance’, ‘transfer’ and ‘varistor’.

The French connection

At the same time over the water in France, two German physicists working for Compagnie des Freins et Signaux were at a similar stage in the development of a point contact device, which they went on to call the ‘transistron’ when it was released.  

Herbert Mataré and Heinrich Welker released the transistron a few months after the Bell Labs transistor was announced but was engineered completely without influence by their American counterpart due to the secrecy around the Bell project.

Where we are now

The first germanium transistors were used in computers as a replacement for their predecessor vacuum tubes, and transistor car radios were produced all within only six years of its invention.

The first transistor was made with germanium, but since the material can’t withstand heats of more than 180˚F (82.2˚C), in 1954 Bell Labs switched to silicon. Later that year Texas Instruments began mass-producing silicon transistors.

First silicon transistor made in 1954 by Bell Labs, then Texas Instruments made first commercial mass produced silicon transistor the same year. Six years later in 1960 the first in the direct bloodline of modern transistors was made, again by Bell Labs – the metal-oxide-semiconductor field-effect Transistor (MOSFET).

Between then and now, most transistor technology has been based on the MOSFET, with the size shrinking from 40 micrometres when they were first invented, to the current average being about 14 nanometres.

The latest in transistor technology is called the RibbonFET. The technology was announced by Intel in 2021, and is a transistor whose gate surrounds the channel. The tech is due to come into use in 2024 when Intel change from nanometres to, the even smaller measuring unit, Angstrom.

There is also other tech that is being developed as the years march on, including research into the use of 2D materials like graphene.

If you’re looking for electronic components, Cyclops are here to help. Contact us at sales@cylops-electronics.com to order hard-to-find or obsolete electronic components. You can also use the rapid enquiry form on our website https://www.cyclops-electronics.com/

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Component Shortage Passive Components

The tech industry is bracing for a potential shortage of passive electronic components

By now, everyone has heard of the global semiconductor shortage. Still, the tech industry is bracing itself for an altogether larger shortage of passive electronic components that could reduce manufacturing output across multiple categories.

Passive components do not generate energy but can store and dissipate it. They include resistors, inductors (coils), capacitors, transformers, and diodes, connecting to active elements in circuits. Passives are necessary for circuit architecture, so the shortage is bad news for the electronics industry as a whole.

The current state of the passive component shortage 

The truth is there has been a shortage of certain passive components since the coronavirus pandemic hit in 2020, particularly with multilayer ceramic capacitors (MLCCs), which can be difficult to get hold of in large quantities.

Certain diodes, transistors and resistors are also in shorter supply than they were in 2019, partly because of the pandemic and a shift in manufacturing investment for active components, which have a higher margin.

You also need to look at consumer trends (what people are buying). Smartphone and smartwatch sales are higher than ever, and smart ‘Internet of Things’ devices are growing in popularity rapidly, not to mention in availability.

These devices require a lot of passive components. For example, a typical smartphone requires over 1,000 capacitors. Cars are also huge consumers of passive components, with an electric car requiring around 22,000 MLCCs alone.

The trend for next-generation technology adoption is up across all categories, be it the Internet of Things, edge computing, semi-autonomous cars and 5G. Passive components are in more demand than ever at a time when supplies are under pressure.

Price rises are now inevitable 

The price for most passive components has risen by the largest amount in over a decade in 2021, caused by supply and demand economics and a price explosion for common materials like tin, aluminium and copper, as well as rare earth metals.

While some suppliers can afford to take a hit on profits, for most, raising prices is inevitable to ensure the viability of operations.

With higher component prices and greater shortages, it is more important than ever for companies to bolster their supply chains. Complacency is dangerous in today’s market, and no company is immune to disruption.

How to beat the passive components shortage 

The passive components shortage is likely to get worse before it gets better, but there are several ways you can bolster your supply chain:

  • Equivalents:Specifying equivalent passive components is a sound way to keep your supply chain moving. When a specific passive component isn’t available, an equivalent may be available that functions in exactly the same way.
  • Ditch outdated components:Outdated components have limited or no manufacturing output when discontinued. Upgrading to modern components that are manufactured in larger quantities can help you meet demand.
  • Partner with a global distributor:Global components distributors like us source and deliver day-to-day, shortage, hard-to-find and obsolete electronic components. We can help keep your supply chain moving in uncertain times. Contact us today SALES@CYCLOPS-ELECTRONICS.COM
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Transistors

The multimodal transistor (MMT) is a new design philosophy for electronics

Researchers from the University of Surrey and University of Rennes have developed a technology called the multimodal transistor (MMT), which could revolutionise electronics by simplifying circuits and increasing design freedom.

The multimodal transistor is a thin-film transistor that performs the same job as more complex circuits. The MMT sandwiches metals, insulators and semiconductors together in a package that’s considerably thinner than a normal circuit.

However, the key breakthrough with the MMT is its immunity to parasitic effects (unwanted oscillations). The MMT allows consistent, repeatable signals, increasing a transistor’s performance. This is necessary for precision circuits to function as intended and is especially useful for next-gen tech like AI and robotics.

How it works

In the image below, we can see the design of the MMT. CG1 provides the means to control the quantity of charge, while CG2 is the channel control gate. CG1 controls the current level and CG2 controls the on/off state.

This is a massive shift in transistor design because it enables far greater engineering freedom. It is a simple and elegant design, yet it is so useful. It has numerous applications in analogue computation and hardware learning.

Digital-to-analogue conversion

MOSFET transistors are one of the building blocks of modern electronics, but they are non-linear and inefficient.

In a conventional circuit, gate electrodes are used to control a transistor’s ability to pass current. The MMT works differently. Instead of using gate electrodes, it controls on/off switching independently from the amount of current that passes through. This allows the MMT to operate at a higher speed with a linear dependence between input and output. This is useful for digital-to-analogue conversion.

The breakthrough in all its glory

The MMT transforms the humble transistor into a linear device that delivers a linear dependence between input and output. It separates charge injection from conduction, a new design that achieves independent current on/off switching.

There is a profound increase in switching speed as a result of this technology, enabling engineers to develop faster electronics. Researchers estimate that the switching speed is as much as 10 times faster. Also, fewer transistors are needed, increasing the yield rate and reducing the cost to manufacture the circuit.  

Just how revolutionary the MMT will be remains to be seen. After all, this is a technology without commercialisation. It could find its way into the electronics we use on a daily basis, like our phones. The potential is for the MMT to be printable, allowing for mass production and integration into billions of electrical devices.

With devices getting smarter and digital transformation advancing at a rapid rate, the electronics industry is booming. Semiconductor foundries are at peek capacity and more electrical devices are being sold than ever. The MMT is a unique solution to a problem, and it could make manufacturing electronics cheaper.   

With this, comes a great opportunity for the MMT to replace MOSFET transistors. We can think of few other design philosophies with such wicked potential.

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