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66 DESIGN007 MAGAZINE I SEPTEMBER 2020 As you can see, the PCB deserves our admi- ration for all the heat and pressure it has to deal with during manufacturing, but that is just the beginning. Next comes the regular day in and day out thermal stress of the board's normal operating environment. All those elec- tronic components can generate a lot of heat in themselves, and life for the board can get pretty toasty. That is what PCBs are created for, though, and why PCB designers like you put so much effort into designing them to sur- vive and flourish in all that heat. A PCB Designer's Job We start by designing boards with symmetri- cal layers of precisely-controlled copper evenly spread out to help with the fabrication process. We also take care in the placement and rout- ing of PCB components to ensure there aren't any problems with soldering during assem- bly. Additionally, we design the boards with their operating temperatures in mind by giv- ing hot parts the space they need, as well as placing them where they can leverage the air- flow across the board for cooling. We also use thermal vias to distribute heat throughout the board and incorporate heat sinks, fans, and other thermal management tools and devices, as necessary. As PCB designers, we are accustomed to using a variety of procedures to manage the heat on our PCBs. However, the question is, "Do we give the same level of attention to man- aging the heat in our jobs as PCB designers?" Many designers tell me that they often find themselves under a lot of pressure while doing their work, which puts them squarely in the hot seat, looking for a fresh breeze of relief. Four Techniques We are already good at PCB design thermal management, so let's consider four techniques in thermal management for PCB designers that might help. 1. Plan a Schedule A lot of folks will ride the wave of the day in the performance of their jobs without any sort of planning at all. While this works for repetitive tasks, it can create a lot of stress for those who have schedule obligations that must be met. Certainly, we have our meetings and other company events planned in advance, so why not put a schedule around our design work too? The goal here is to prevent every- thing from piling up at the last moment and creating a catastrophic train-wreck with your deliverables. By planning regular milestones as you work, you can better manage the proj- ect's long-range delivery dates and give your- self plenty of room to make schedule adjust- ments along the way, if necessary. 2. Manage Interruptions When working in an environment where there are continual interruptions, it can be easy to get frustrated as each new interrup- tion raises our temperature another notch. For PCB designers, this can be especially trouble- some as the design process involves keep- ing several sequential tasks going all at the same time. "This via can move over as soon as this resistor is rotated, which I can do as soon as these traces are re-routed, which can only happen after I slide the capacitor a little down and to the left…" You can almost see the tasks floating around a designer's head like little bubbles until an interruption causes all the bubbles to simultaneously pop, taking all those ideas crashing to the floor with them. To avoid this, try scheduling times when you shut down electronic interruptions and go dark to the outside world for a while. Of course, this requires planning so that other team members (and your boss) know what you are doing, but carving out blocks of uninterrupted time in your schedule can be a real game changer. 3. Document the Process The temperature in the design room often gets elevated through poor communication. People may not know what they are supposed to be doing, or they may not know what you are doing. The best way to remedy this is through documentation. Make sure that every- one knows who the stakeholders are and who is calling the shots. It is also helpful if everyone has access to project schedules and timelines.