Issue link: https://iconnect007.uberflip.com/i/1511130
NOVEMBER 2023 I DESIGN007 MAGAZINE 9 Andy Shaughnessy is managing editor of Design007 Magazine. He has been covering PCB design for 23 years. To read past columns, click here. Some designers over-constrain their entire boards when only a handful of features actu- ally require tight tolerances. Every dimension specifically called out is bought and paid for, because it has to be inspected, and that can be an expensive habit. So, in this issue, our expert contributors explain how to design PCBs without making them complex and over-constrained—what- ever the level of technology. We also discuss the effect your decisions and tradeoffs have on design complexity, as well as the need to thoroughly understand how electrical and manufacturing limitations can lead to over- constraining your board. We start off with a conversation with Kris Moyer, who explains why "one size fits all" is not a great plan for setting board constraints. Next, Martyn Gaudion discusses various ways to design the simplest—and best—stackup possible. Doug Brooks and Johannes Adam tell us why thermal vias are usually ineffective at dissipating heat, but do a great job of blocking potential routing channels. Chris Young has a great set of guidelines called "8 Simple Rules for Streamlining Your Design." Zach Peterson explains why designers should stop designing PCBs like Ferraris, the famously complex Italian supercars. Tim Haag describes why designers should follow the lead of "Star Trek's" Montgomery "Scotty" Scott and keep their designs simple, and Joe Fjelstad points out why the simplest design is usually the best. We also have columns by Matt Stevenson and Barry Olney, and Steve Williams has a conver- sation with American Standard Circuit's John Johnson on UHDI. Trade show season is here, and we'll be covering productronica next week. DESIGN007 Using laser light, researchers have developed the most robust method currently known to con- trol individual qubits made of the chemical ele- ment barium. The ability to reliably control a qubit is an important achievement for realizing future functional quantum computers. This new method, developed at the University of Waterloo's Institute for Quantum Computing (IQC), uses a small glass waveguide to separate laser beams and focus them four microns apart, about four-hundredths of the width of a single human hair. The researchers created a waveguide chip that divides a single laser beam into 16 different chan- nels of light. Each channel is then directed into individual optical fibre-based modulators which independently provide agile control over each laser beam's intensity, frequency, and phase. The laser beams are then focused down to their small spacing using a series of optical lenses similar to a telescope. The researchers confirmed each laser beam's focus and control by measuring them with precise camera sensors. The new waveguide method demonstrates a simple and precise method of control, showing promise for manipulating ions to encode and process quantum data and for implementation in quantum simulation and computing. (Source: University of Waterloo) Processing Quantum Information Reliably