Heavy Copper PCB Design Tips

Nowadays, heavy copper PCB (copper thickness >4 oz) has become popular in PCB industry because it is suitable for high-voltage and high-power application, as most PCBs are manufactured just for low-voltage or low-power application with traces generally contain from 0.5 oz to 3 oz copper weight. 

But some PCB designers always get the boards fail the current test, why? Because they sometimes forget a fact that every PCB facility has its process limits and capabilities, even on the same design, so once you choose a manufacturer to take your heavy copper PCBs, you’d better consult them three questions before designing. 

1. Their Min Trace Width

   Trace width is a requirement that all designers pay great attention to ensure that the trace can handle the required current capacity on the project. How much current can a copper circuit safely carry and how much heat rise can your project withstand? They are always determined by the traces on the circuits. Thus, it is important for you to know their min trace width and space which they can make for heavy copper PCB.

2. Material for Heavy Copper PCBs

   For PCB in low-voltage or low-power application, use standard FR-4 or high-temperature FR-4 is enough. But as to those projects with heavy copper PCBs which will be used in high-voltage and high-power application, it is ideal to use high Tg material to make sure your final PCBs can endure higher processing temperature.

3. Their Etching Process on Heavy Copper PCBs

   Standard PCBs, double-sides or multi-layers, are manufactured with a combination of copper etching and plating processes. If the way they etch on heavy copper PCBs is the same with etching on standard board, you’ better ask them the base copper on the material and how to etch and plate the extra copper on the circuits. 

All in all, when designing heavy copper PCBs, more contact with your PCB manufacturer for all technical and manufacturing issues can really help you a lot.

Solder Starved

Solder starvation occurs when adequate volumes of solder are not available to effect a perfectly-shaped solder joint, that means a solder starved joint simply does not have enough solder. It may make good electrical contact, but it is hard to verify by inspection. In any case, it is not a strong joint and may develop stress cracks, intermittent short circuit and fail over time.

Frequently, solder starvation occurs in surface mount technology (SMT) when solder paste deposits are inadequate. This happens because: The single-thickness stencil is designed for the majority of smaller components, starving the few larger components of solder volume. Or high-use interfaces, such as connectors and USB ports, require extra solder - to assure their solder joints survive the constant use in the field. Or smaller, more tightly compacted circuit boards don't allow for deposition of enough solder paste.

So, how do you solve this increasingly common problem? Actually, it is simple. Just re-heating the joint and add more solder to which you need it, and a good strong joint is made.

E-Waste

E-waste or electronic waste is the left over PCBs, components, PVC or plastic cases, body, etc., of your old electronic appliances, such as a TV, refrigerator, dish washer that you have thrown out. It is one of the fastest growing types of waste produced on the planet. According to a report on e-waste, by 2017, all of that year’s end-of-life refrigerators, TVs, mobile phones, computers, monitors, e-toys and other products with a battery or electrical cord worldwide could fill a line of 40-ton trucks end-to-end on a highway straddling three quarters of the Equator, the weight equivalent of 200 Empire State Buildings or 11 Great Pyramids of Giza. The US has the world’s highest figure of 9.4 million tons and China generated the second highest e-waste total of 7.3 million tons. The report also states that the total amount of e-waste generated by 2017 will be 65.4 million metric tons.

What can we do to stop the severe situation? Well, the simple answer is stop over-consumption. But that could take a long time to actually come into action. The next big thing is too start recycling every bit of those electronic appliances and gadgets that our leaving our house. We can open up the body of each of these appliances take out the PCBs and reuse the components.

Surface-Mount Devices

Surface-mount devices or SMDs are used in a growing number of commercial and industrial products and become one of basic components when use surface-mount technology to produce PCBs. In the early stages of printed circuit boards’ production, all through-hole assembly was done in the traditional way by workers. After launching the first automatic machines which can do some easy job like put pins on printed circuit boards, however, complicated components still need workers to install in order to keep the work efficient of the printed circuit boards. Working with SMDs can be challenging, and mastering this technology takes a little more patient, while learning these techniques will help you succeed when working with small components. 

In-Circuit Test

In-circuit test (abbreviated ICT) is a useful and efficient tool for printed circuit board test by measuring each component in turn to check that it is in place and of the correct value. Some in-circuit testers are able to test some of the functionality of some integrated circuits, and in this way give a high degree of confidence in the build and probability of operation of the board. Parameters covering shorts, opens, resistance, capacitance, and other basic quantities can easily show whether the assembly is correctly fabricated and have a very high chance of performing to its specification. 

PCBs Assist Emergency Personnel

When we talk about printed circuit boards, the first thing that comes to our mind is consumer electronics. Only insert high-quality PCBs on computers, phones, entertainment systems and more, can we utilize them as expected. Actually, PCBs are not limited in the consumer electronics, they also can be used to help save lives by emergency responders around the country, such as firefighting, police, medical treatment, etc. 

Firefighters – Imaging tools allow fire crews to map out the size and location of a fire and with the help of existed geography and topography, firefighters can make the best action plan which can both make the action more efficient and protect firefighters’ lives better. 

Police Officers –PCBs can be placed in gun grips or other equipment that will register when an officer has fired his or her weapon. That can then alert other units nearby or a dispatcher.

Recycle Old PCBs

As we all know, environment pollution is severely serious which does harm to people’s health. So we should do our part to protect the environment as both an individual and a part of our company which will allow us all to conserve valuable resources, reduce energy consumption and create a cleaner environment for our future. We can achieve our objectives by recycling old printed circuit boards which are made from chemicals and materials that are hazardous to the environment. Those raw materials are illegal to dump without special treatment, because if these items make their way into a landfill they will just sit there, allowing the chemicals to potentially seep into the soil or get into water supplies. That’s the reason why we appeal to PCB users and manufacturers to recycle old PCBs. We have the responsibility to ensure that the raw materials are properly disposed of and meet regulations in order to protect our environment.