App Notes: What Are They Good For?

Estimated reading time: 2 minutes

There are several schools of thought regarding IC manufacturers’ app notes. Some engineering departments expect their PCB designers and design engineers to follow app notes exactly. But the top PCB design instructors often warn their classes to assume app notes are wrong until they’ve been proven right.

We wanted to find out more about this, so we spoke with Geof Lipman, director of operations for part data at Octopart.com, a component data platform acquired by Altium in 2015. Geof shared his thoughts on app notes, datasheets, and the need for due diligence when utilizing any unfamiliar data.

Andy Shaughnessy: Geof, why don’t you start off by telling us about your duties as director of part data at Octopart, and we’ll go from there.

Geof Lipman: I was brought on because of my background in electrical engineering and manufacturing. And as a member of the Altium organization, we focus on the needs of electrical engineers. I help to guide our acquisition of part data, the types of part data that we take or get, and who we get it from, such as which manufacturers and distributors. We work in concert with our business development department so that we can do this in ways that don’t lose us money.

And when I say types of part data, app notes are one type. Our technical specifications would be things like mechanical dimensions and electrical characteristics, including input voltage, output voltage, and supply voltage— the long laundry list of specs that we see. The other types of part data would be datasheets, CAD models, and cross-references. I help sort out the most valuable thing for Octopart users.

Shaughnessy: I understand that you don’t hand out app notes with each part. What is the reasoning behind that?

Lipman: Our prime mover for that would be usefulness for our user base. There are many different types of parts. People tend to focus on things like integrated circuits because they’re the “glamorous” parts, but most parts that get sold are resistors and capacitors, which are “boring.” But nevertheless, people need to specify them, and they need to know how they perform and what they cost. First, we focus on getting the data that every part has. Every part costs money, every part has supply chain information, and almost every single part has a datasheet and specifications.

Something like 70% of the parts that get used in the electronics industry can be mounted to a circuit board—in which case, having ECAD models for the various ECAD suites is a helpful thing for people to have. Sometimes, you can’t get the part that you want, so you need to get something that’s adjacent to it. Having that cross-reference information is useful to people. We go down through each of these assets. Which are the assets that will help the greatest number of users in the greatest number of cases that we can imagine? You’ll see on Octopart that most of our parts have datasheets.

To read this entire interview, which appeared in the June 2020 issue of Design007 Magazine, click here.