Electronic Circuit Board (PCB) Design & Manufacturing

What are the rules of circuit design?

To build a brand and secure a trouble-free place in the industry, designs are produced within a defined set of rules.

A professional circuit design should contain as few errors as possible, so many rules are defined to minimise them. The most fundamental of these are the drill hole diameter relative to track width, the spacing between holes and the minimum clearance between tracks.

To create a globally competitive, high-volume product, various standards must also be taken into account. That is why we work to international standards – to provide a better service and guarantee quality.

What are international standards?

International standards are rules specified in designs so that companies comply with similar requirements. Standards are available to users for a fee, which ranges from roughly $70 to $2,000 depending on the standard. They can be obtained as digital documents or printed books, and licences may be for a single user or an entire company.

You can browse hundreds of electronics standards used in industrial equipment today via this link.

Which standards benefit us?

International standards are mostly developed by organisations based in the United States and the United Kingdom. They allow finished products to be tested in areas such as user safety, operating conditions, design and materials so that they can enter international markets.

Together, standards make a product robust and enable it to circulate freely in countries and under bodies such as CE and the Turkish Standards Institution (TSE). Otherwise, serious problems may arise at customs, in sales, with users and in marketing.

Hole Diameter and Track Width in Electronic Circuit Design

How are hole diameters determined?

On single- and double-layer boards the minimum hole diameter is 0.3 mm; 0.25 mm is preferred on boards with four or more copper layers. This rule depends entirely on the manufacturer’s capabilities. The designer enters the board design rules into the design software so that drawing errors are minimised. As a result, time lost to problems during manufacturing is avoided.

How is track width determined?

The designer selects the track width according to current and voltage. However, this information alone is not enough: track width is also directly affected by the conductor material and copper thickness of the board. Copper is by far the most widely used conductor. In devices that require natural cooling, such as lighting, the conductor material may differ.

Designs typically use 1.6 mm FR-4 with 1 oz (35 µm) copper, although the material can vary with production requirements. For example, FR-4 is not suitable for antenna PCBs because losses are high at high frequencies and the required transmission range cannot be achieved. Rogers materials are used instead, minimising frequency-related losses in the circuit. You can read more about Rogers materials and how they differ from FR-4 here.

Electronic Board (PCB) Manufacturing

It is important that materials are high quality, that the error rate is kept to a minimum and that boards are tested. PCBWay and JLCPCB are popular for their competitive prices. In Türkiye, Baskı Devre is a strong choice for fast, express board production.

When can my finished board be delivered?

Delivery takes between one week and one month depending on shipping. FedEx is generally used so that boards reach us as quickly as possible. If the PCBs are manufactured in China, the average lead time is two weeks.

Electronic component sourcing

Using genuine components is essential, so widely used distributors such as Digi-Key, Mouser and Farnell are preferred. Özdisan, known for its competitive prices, is preferred when production is fully local. Component sourcing depends entirely on production volume and the target market of the final product. Components for harsh-environment designs are sourced directly from the manufacturers’ authorised distributors.

Design

Both free and well-known commercial tools are used for board design. The most widely used board design programs, supported by a large user community, are DipTrace, Altium Designer and Eagle, with Altium Designer and Eagle being industry leaders. Altium Designer is our primary tool for most designs, although other tools can be used when required. You can read our article on circuit design software here.

Why is documentation so important?

If the design to be prototyped is a one-off, documentation is not essential. But if you have two or more circuit designs and expect to design dozens of boards in future, documentation is well worth the effort. All schematics, descriptions and rules are recorded in the documents, and these rules are followed in any later updates or new designs. Even if your customer or your design house changes, as long as the rules are followed you depend on rules rather than individuals.

For example, suppose you prepared a file and quoted a customer. Some time later, the customer asks for a different quotation. Do you rework the whole quote, or simply update one file? In such cases, the documents created during the design stage – and the rules they contain – make compatibility easier and simplify adding to or removing from the project. Efficiency increases, which shows how important documentation is for simple, efficient work.

When you work with rule-based rather than person-dependent design, the rules help you avoid problems further down the line – keeping you one step ahead of the competition.

Kind regards,
The Oxa Hardware Team