Showing posts for June 2022
30 June 2022
RoHS, REACH, and dangerous substance legislation
RoHS and REACH are two pieces of legislation referring to the control of dangerous substances and chemicals. Companies manufacturing and distributing electronic equipment in Europe must comply to be able to trade.
The Restriction of Hazardous Substances (RoHS) Directive came into force in 2004. With an aim to mitigate the effect of dangerous substances on customers, the Directive restricts the concentration of 10 substances used in Electrical and Electronic Equipment (EEE).
Acceptable levels of restricted substances in a single material are generally less than 0.1% or 1000 parts per million (ppm). For the chemical Cadmium, however, levels must be no more than 0.01% or 100ppm.
Companies must provide proof that they comply with the regulations by way of documentation. This includes a Declaration of Conformity, a record of the assessment procedure for conformity, and any other control documentation.
Since its release in ’04, there have been 3 iterations, with the latest being introduced in July of 2019. RoHS 3.0 introduces 11 new category products and four new substances.
The materials listed include products that could be harmful to not only human health, but the environment too. As such, non-compliance carries with it the potential for a heavy fine.
RoHS certification takes place in several steps:
- Extraction testing of the components takes place to determine the value of the RoHS substances contained.
- On-site manufacturing processes are inspected to ensure RoHS compliance at the facility.
- Review all relevant documentation, including the BOM (Bill of Materials), assembly drawings, and test reports from suppliers.
- Following this, if all is in order a RoHS Certificate of Compliance is issued.
REACH stands for the Registration, Evaluation, Authorisation and Restriction of Chemicals. It was introduced a few years on from RoHS, in 2006.
The scope of REACH is more inclusive than RoHS. It encompasses almost all products manufactured, imported, or sold in the EU or UK.
REACH revolves more around Substances of Very High Concern (SVCH), which includes those considered carcinogenic, mutagenic or toxic for reproduction.
Manufacturers and importers need to register the quantities of substances produced every year. Companies need to safely manage and publicise the risks associated with the substances. They’re also responsible for tracking and managing which substances are being used, and produce safety guidelines for each.
Due to events like Brexit in the UK, RoHS and REACH regulations became transplanted into UK law. Since many substances are imported between mainland Europe and the UK, the legislation in both remained very similar.
As part of the European Union (Withdrawal) Act 2018, REACH was copied into UK legislation, becoming UK REACH in 2021. Although the difference is seemingly in name alone, the two REACHs operate separately, and manufacturers need to comply with both.
REACH for the stars!
Cyclops can supply products that are RoHS and REACH compliant and can provide this information to our customers. This means Cyclops customers can guarantee if they want RoHS compliant parts, they will receive them. So contact Cyclops Electronics today!
This blog post is designed to be informative and is in no way offering advice or guidance on how to interpret legislation.
22 June 2022
Resins and coatings for electronic 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 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.
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.
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 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.
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.
15 June 2022
Electronic Components of a hearing aid
Hearing aids are an essential device that can help those with hearing loss to experience sound. The gadget comes in an analogue or digital format, with both using electronic components to amplify sound for the user.
Both types of hearing aid, analogue and digital, contain semiconductors for the conversion of sound waves to a different medium, and then back to amplified sound waves.
The main components of a hearing aid are the battery, microphone, amplifier, receiver, and digital signal processor or mini-chip.
The battery, unsurprisingly, is the power source of the device. Depending on the type of hearing aid it can be a disposable one or a rechargeable one.
The microphone can be directional, which means it can only pick up sound from a certain direction, which is in front of the hearing aid user. The alternative, omnidirectional microphones, can detect sound coming from all angles.
The amplifier receives signals from the microphone and amplifies it to different levels depending on the user’s hearing.
The receiver gets signals from the amplifier and converts them back into sound signals.
The digital signal processor, also called a mini-chip, is what’s responsible for all of the processes within the hearing aid. The heart of your hearing, if you will.
As with all industries, hearing aids were affected by the chip shortages caused by the pandemic and increased demand for chips.
US manufacturers were also negatively impacted by Storm Ida in 2021, and other manufacturers globally reported that orders would take longer to fulfil than in previous years.
However, despite the obstacles the hearing aid industry faced thanks to covid, it has done a remarkable job of recovering compared to some industries, which are still struggling to meet demand even now.
Digital hearing aid advantages
As technology has improved over the years, traditional analogue hearing aids have slowly been replaced by digital versions. Analogue devices would convert the sound waves into electrical signals, that would then be amplified and transmitted to the user. This type of hearing aid, while great for its time, was not the most authentic hearing experience for its users.
The newer digital hearing aid instead converts the signals into numerical codes before amplifying them to different levels and to different pitches depending on the information attached to the numerical signals.
Digital aids can be adjusted more closely to a user’s needs, too, because there is more flexibility within the components within. They often have Bluetooth capabilities too, being able to connect to phones and TVs. There will, however, be an additional cost that comes with the increased complexity and range of abilities.
08 June 2022
Traditional fuses and eFuses
Fuses are an essential electronic component in most circuits, and act as a safety feature to keep the other components within the circuit safe. Billions are used today to safeguard against circuit failures.
The purpose of fuses
If a circuit is overloaded, or there is a voltage surge, the fuse essentially self-destructs to protect the rest of the circuit. A traditional fuse contains a central fusible element that, when heated to excessive temperatures, melts and stops the flow of current through the circuit.
The speed that the thermal fuse melts depends on the how much heat is being caused by the current, and what temperature the fuse is designed to react to. The fuse can be designed with different melting elements that have varying melting points and resistance, so the currents they can cope with can differ.
The new kid on the block is the newer electronic fuse, or eFuse. This component is an updated, re-usable version of the more traditional thermal, one-use fuse.
This component comprises of a field-effect transistor (FET) and a sense resistor. The resistor measures the voltage across it, and when it exceeds a certain limit, the current is cut off by the FET. Usually, the eFuse is placed in series with a thermal fuse rather than replacing it, giving the circuit a second layer of more localised protection for components.
Often eFuses are used as a protection when components are plugged into a computer while the power is still on, also called hot-swapping. In automotive applications, programmable logic controllers (PLCs) and battery management eFuses are a great tool to protect the circuits.
An offer you can’t reFuse.
As thermal fuses have been around for so long, it’s unsurprising that there are certain things the more recent eFuse can do slightly better.
The first and most straightforward advantage is the lifespan: once a thermal fuse is activated and the element inside it fuses, it will have to be replaced. The eFuse, however, can be reset and used multiple times without requiring replacement.
The eFuse is also able to respond to a circuit overload more quickly and works in circuits with a lower current and voltage. For some eFuses the current level it reacts at is set, but for some types it can be altered by an external resistor.
It’s possible to create a homemade eFuse too, just by putting together a few FETs, a resistor and an inductor, which filters the output and acts as your sense resistor.
Reaching melting point
Both fuses have their uses, and utilised together are even more effective as a circuit failsafe. However, each designer must consider their requirements and what will best suit their clients. There are scenarios where the thermal fuse just won’t do the job, and it’s better to be safe than sorry, right?
Enter Electronic Component part number below.