PCB Design Guidelines That Make Boards Manufacturable Most layout mistakes are not made because the rules are unknown. They are made because the rules are applied only to the parts of the board that the designer is thinking about at the time, and the rest is drawn by habit. Guidelines…

Electroplating Via Filling Process for HDI Boards As devices became denser, the holes that connect their layers became smaller, and once a hole is small enough that conventional plating cannot coat its walls uniformly, the process has to change. Instead of coating the barrel, the hole is filled completely with…

Placement Order and Pad Positioning in PCB Layout Placement is the half of layout that decides how difficult the other half will be. Two engineers can route the same schematic into boards with the same component count, and one will finish in a week while the other fights for space…

PCB Layout Decisions That Affect Production Layout is usually optimised for electrical performance, and then handed to manufacturing with the expectation that it will be built as drawn. In practice a board that is electrically excellent can still be expensive to produce, difficult to assemble and unpredictable in yield, and…

PCB Dimensional Stability and Expansion Control A printed circuit board is a laminate of materials with different thermal and mechanical properties, pressed together under heat and then subjected to a series of wet processes and thermal cycles. Each of those steps changes the dimensions of the panel, and the accumulative…

AIoT Processor Core Board Design Considerations A modern processor for embedded vision and edge computing packs eight or more cores, a graphics engine, a neural accelerator and a set of high-speed peripherals into a package that may have a thousand balls at a pitch below a millimetre. The core board…

FPGA Board Design for High Speed Interfaces An FPGA is not simply a large component. It is a system on a package, with dozens of high-speed serial channels, several parallel memory interfaces and a power demand that changes faster than any regulator can respond to. The board that carries it…

Via in Pad or Plated Through: Choosing by Cost Placing a via directly in a component pad is a technique that solves a real problem and creates a real cost. It shortens the connection from a fine-pitch device to the inner layers and it frees routing space on the surface,…

Multilayer PCB Advantages in High Speed Design Once a design contains signals whose edges are fast relative to the length of the traces they travel along, the board stops being a container for wires and becomes part of the circuit. At that point the number of layers stops being a…

PCB Design Quality: The Characteristics That Matter Two boards can satisfy the same schematic and behave completely differently in the field. The difference is design quality, and it is not a single property but a set of them, each of which can be assessed before the board is built. The…