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Many IC manufacturers already have reference PCB designs (or they have them for their EVMs) that you can look at for guidance. Personally I would rather adapt t

Many IC manufacturers already have reference PCB designs (or they have them for their EVMs) that you can look at for guidance. Personally I would rather adapt that for my design than modify a pre-made section in the EDA tools. I've also found that the choices made in the reference PCB may not always be the best choice for your design. For example the reference may have a 802 cap but you'd rather use a 603. Same for routing, the reference may be a 2-layer board but you're doing a 4-layer. You may have other ICs that may be able to share certain components. And so on. Part stock and pricing also fluctuates quite often, so a manufacturer-provided BOM (which BTW exists for some EVMs) may not always work assuming that those are the exact components you want. I haven't designed a PCB in a while but from when I did it the reasons above were why people weren't really keen on pre-made "libraries" of building blocks.

michaelt 4y ago
Redrawing designs yourself is indeed commonplace in the electronics industry, but coming from the software world it's always struck me as a mix of weak tooling and outdated conventions, rather than something inherent to the industry. After all, why shouldn't a reference design be defined in a parametric way? Your switch-mode power supply might need a class-X value-Y precision-Z voltage-A ESR-B at frequency-C capacitor, while my decoupling capacitor just needs to be >3.3v 100nF and doesn't mind if you use one 5x larger. Personally I've made innumerable designs where, at the schematic stage, I've copy-pasted a microcontroller and a crystal and capacitors and programming header and reset pull-up. It's a common-sense way to avoid human error, and a time saver too. The design reuse is happening - the tools just haven't caught up.
- eupfhoria 4y ago
- techdragon 4y ago
  The tools have had over ten years (if not twenty) of a growing maker movement bringing new people without training in EDA tools who would benefit from this kind of reuse… and it hasn’t caught up. There seems to be a perception that you should be able to do these basic things, like copying a circuit design into your EDA tool, and understanding which basic components to pick like all the little capacitors and pull up/down resistors. This perception prevents people from viewing it as a worthwhile feature.
- DHaldane 4y ago
  You're right - reference designs should be parametric. Everybody wants this including the semiconductor companies. Seems like the failure in the tools is that parametric generation is really badly supported by the usual graphics-oriented approach.

michaelt 4y ago

Redrawing designs yourself is indeed commonplace in the electronics industry, but coming from the software world it's always struck me as a mix of weak tooling and outdated conventions, rather than something inherent to the industry. After all, why shouldn't a reference design be defined in a parametric way? Your switch-mode power supply might need a class-X value-Y precision-Z voltage-A ESR-B at frequency-C capacitor, while my decoupling capacitor just needs to be >3.3v 100nF and doesn't mind if you use one 5x larger. Personally I've made innumerable designs where, at the schematic stage, I've copy-pasted a microcontroller and a crystal and capacitors and programming header and reset pull-up. It's a common-sense way to avoid human error, and a time saver too. The design reuse is happening - the tools just haven't caught up.

eupfhoria 4y ago
techdragon 4y ago
The tools have had over ten years (if not twenty) of a growing maker movement bringing new people without training in EDA tools who would benefit from this kind of reuse… and it hasn’t caught up. There seems to be a perception that you should be able to do these basic things, like copying a circuit design into your EDA tool, and understanding which basic components to pick like all the little capacitors and pull up/down resistors. This perception prevents people from viewing it as a worthwhile feature.
DHaldane 4y ago
You're right - reference designs should be parametric. Everybody wants this including the semiconductor companies. Seems like the failure in the tools is that parametric generation is really badly supported by the usual graphics-oriented approach.