8 tips for PCB designers

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In the 21st Century, electronic equipment can perform an incredible array of tasks, from automatically recording Antiques Roadshow… to automatically hovering round your feet as you watch it.  However, at the heart of any piece of electronic equipment is its circuit board… its neural wiring.  And if you get that wrong, you may find your dream design of an automated hoover becomes an antique itself, before you can find the off switch.

Think of it this way: our bodies, with all their integral organs, are really just the mechanics for moving the brain around.  And the same holds true for electronics, where the design of the circuit board remains integral to the success of the final product.  It’s natural selection… only artificial.  So it follows that it makes sense to get your circuit board perfectly designed, and correctly manufactured, from the off… and then everything else should fall into place.

preparing your PCB design for productionOf course the design process covers a variety of aspects.  Electronic life begins with the individual transistors that combine to form an integrated circuit.  With more simple circuits, you may well be able to handle the design process yourself, without overcomplicating things with the sort of structured design process that might turn a mouse into a platypus.

However, soon you will find thoughts turn to much more complex systems and designs.  Here you may find that you’ll need to turn to professionals.  With very complicated designs you may even need a whole design team, trained to follow a designated approach to design, even creating computer simulations of the design to test them out digitally, before the costs of actual physical manufacture.

In such cases, a specialised electronics engineer will design the board itself.  Perhaps not surprisingly, this person will have a very particular skillset, able to understand not only the design and layout process itself – including the PCB CAD system and design software – but also to have a vision for the end product.  They must understand how a design from someone’s imagination can actually be realised as a PCB that can be usefully and efficiently be then manufactured, bearing in mind all techniques and electronic industry standards. A layout will then be based on the PCB CAD system’s schematic and a layout specialist will control its physical creation… breathing life into your grand design.

So, if you are still looking to handle the design and build itself, you need to feel confident with these processes and guidelines.  Of course no manuals or books can compete with experience, and that’s where Hi5 is more than happy to step in, if you would like us to assist. In the interim, here are 8 pointers to help you on your way to successful printed circuit board design and build.

8 ways to best prepare your PCB designs for manufacture

  1.  Keep layers in pairs. You do not save any money with a five layer over a six layer, and they are more difficult to keep flat.
  2.  Wherever possible, use the largest via hole and pad appropriate to the density of the board.  Small holes are more costly, slow down the production process and may be less reliable.
  3.  Group together hole sizes, to use the minimum number of drills commensurate with your processing demands.
  4.  Buried and blind vias require special process routes, and add time – use them only if you need to. The same is true for half-holes, edge plating and plated slots.
  5.  Avoid isolated pads and holes, especially close to the edge of boards, as they give problems in processing and may impair reliability.
  6.  When you set up the defaults in your CAD package, spend an extra bit of time checking your default settings, so that ground areas are not drawn with vast numbers of thin lines, so that dimensions are not to ten decimal places, minimum track width is achievable and minimum gap is appropriate to the technology of the design. If you are doing a simpler design than usual, up the settings and save some money in the long run.
  7.  Keep to white notation if possible. We now generally use a large high precision ink-jet printer, but it only prints white.
  8. When putting a board into a manufacturing panel, do this in concert with us. All “real-estate” is paid for one way or another, whether it is a poor yield on our manufacturing panel or a big salve-edge for the finger conveyor. A soldering pallet can pay back in no time with cheaper boards.

The best tip is to talk to us, even if you’ve been designing for years. Naturally with developments in electronics things can change, and helping us to help you saves both money… and grey hairs!








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