One of the most frequently discussed topics in the making of printed circuit board assembly is the placement of components. It also happens to be one of the most heated debates in the industry. Component placement on printed circuit board assembly is an extremely important task for a number of reasons, not least because how components are placed will affect manufacturing yields, time to production, performance of the board and more.

Component placement on printed circuit board assembly is one of the most crucial aspects of board design, influencing its manufacture, performance and longevity.

We have used this phrase before and it seems to be common sentiment across the industry that component placement is an art not an exact science. And how could it be, balancing heat management, board size and convenient placement are all too often divergent goals.

In this article we look at some of the more ‘accepted’ wisdom on component placement on printed circuit board assembly.

• Manufacturing – A printed circuit board assembly must be manufactured and it is the first aspect that must be considered in component placement. As a general rule, smaller components must be placed before larger ones so that connections don’t remain unsoldered.
   
• Edges – Placing components right to the edge of printed circuit board assembly makes handling the board all that more difficult. That holds true during manufacturing as well as when the board must be installed or worked on after the fact.
   
• Connections – It is too tempting to huddle together all the components closely. But, beware, other than making their mounting more tenuous, connection routes also become impossibly hard. Add to that the pins that must accommodate the components themselves taking up space and the suddenly the printed circuit board assembly needs to be redesigned.
   
• Spacing – Giving ‘breathing room’ to components on the board is a common adage too. Other than aiding heat dissipation, adding a little extra space reduces the chances of an electrical current arcing between circuits. What’s more, it can reduce noise and enhance the signal being transmitted.