How to Keep With New Technology Developments in Microelectronics

Businesses desiring to make a career out of PCB design will have to catch up and keep up with the latest technological developments in microelectronics.

FREMONT, CA:As new electronic devices are developed and features are included, the space on a printed circuit board (PCB) becomes more important. Moreover, as devices need to be smaller due to consumer demand, PCBs should be dense to fit all the components. As a result, proper use of microelectronics is the best practice in PCB production, including design and layout, fabrication, and PCB assembly, ensuring devices function well even with reduced form factors.

PCB design is at the nexus of electrical and mechanical design, making particular build requirements unique. A PCB design expert starts with simple two- and four-layer PCBs with plated through-hole (PTH) components. In addition, they will explain the progress toward surface mount technology (SMT) and eventually high-density interconnect (HDI) designs. Furthermore, one can start with analogue or digital designs and work towards mixed signal efforts.

Today’s beginner to intermediate PCB designer needs all these tools. Consumer demands and industry requirements seek new methods, so PCB designers of tomorrow should learn new practices. The new world of microelectronics has ubiquitous high-speed and high-frequency technologies located in every corner. Transistors come by the billions and fit on every business card, and PCB layer counts are well into the double digits. On the other hand, linewidths are becoming smaller and seem to disappear. Micrones are being used because thousandths of an inch are large to measure.

The components for simple boards of the past are difficult to source as they would lead to bulky and power-hungry designs. In terms of surface-mounted devices, the pin pitch gets tighter with every new generation. The common components have pins around the perimeter with typical centre-to-centre dimensions of 0.5 and 0.4 millimetres.

PTH devices are usually made with pins centred on 2.54 mm. The Dual In-Line Packages (DIP) had widely spaced pins on only two sides. Today's modern quad flat-pack (QFP) parts have little surface-mount gull-wing leads. The central area within the perimeter has a large pin that is tied to the ground net for an additional thermal path. The pin count starts at 16 and easily gets to 128 pins. Chip vendors tuck the leads under the gadget to make it more compact, and a quad flat no-lead, or QFN, is what is used in this situation.

Junior PCB designers need to be versed in micro-vias due to the advancements due to the advancements in microelectronics. Implementing micro-vias in a design comes with a few dependencies. The primary concern is that the small diameter of the micro via makes it hard to plate unless the hole is shallow. Even a one-to-one ratio of depth to diameter is a challenge.