Creating a FAQ: how to read a datasheet
After reading various low quality questions Someplace Else today, it (once again) occurred to me that a whole lot of people, mostly hobbyists and engineering students, have no clue how to do the most basic thing of all: how to read a datasheet.
Specifically, what the various parts such as absolute maximum ratings and electrical characteristics mean. What parameters to design after and which ones that are stress values. How to design with margins. How to quickly determine if a certain part is suitable for one's purpose and so on.
There's also lots of engineer jargon like analog/digital characteristics, ambient/junction temperature etc where the reader is expected to know what it means in advance.
I know of no reliable online resources that tell you have to read a datasheet, so I thought about creating a FAQ post about it here. The target audience should be electrical engineering students, not complete laymen.
Ideally this would be some community-maintained project that many users can contribute to, but we don't have "community wiki" like SE.
Question: what is the best way to create a FAQ post like this here if I want multiple users to contribute and maintain the post? The "Papers" category don't quite seem to fit the bill(?).
I am also interested in feedback about what part that would be a good example datasheet. I was thinking about using the classic LM317 LDO from TI as an example, since it's a common and reasonably complex product, but not overwhelmingly so. (And this post shouldn't need to get deep into the technical details.) The datasheet from TI is very good and detailed, containing everything one might expect to find in a generic datasheet, including some extras like lots of applications and layout advise.
4 answers
I agree with Olin and Mu3 answers. I'll add that you should aim not for just one kind of "high level" component, but many more basic ones.
Not every EE course is the same across the world, and many different degrees fall under the EE umbrella term, and not every one of them has the same level of electronics topics treatment.
I would start with the datsheet of very basic components, like common through hole resistors and capacitors, then proceed with jellybean diodes like 1N4148 and 1N4007 and a general indicator LED datasheet.
Maybe throw in the datasheet of a half-watt Zener diode and a photodiode. Maybe also a Schottky diode.
Then low-power BJTs (2N3904,BC550) and MOSFETs (2N7000).
After those, jellybean OPAMPS, like LM358 and TL081 (please, DO NOT talk about the uA741! :-)
At this point, the student can grok also the LM317.
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I think this would make a good Paper.
I know you want others to collaborate, but that's something that doesn't really work. "Community Wiki" certainly never worked right on SE. Too many cooks make a mess, no matter how good each cook is.
Go ahead and write a paper. If the result is good, I'll find a way to link to it from the site help.
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I think the Papers section can be suitable. In the category description post it says:
Example of paper topics: [...] A survey of scattered information, with the paper putting it all in one place.
A self-answered question would also work well, I think, as such questions are also popular on the StackExchange sites and get a lot of attention.
As for the example datasheet, I would perhaps go for some widely used general-purpose op-amp. Op-amps are covered in EE education so most terms in the datasheet should at least be familiar. Using an op-amp should also be a good case study since you can hook it up in different ways and have different part of the datasheet matter more for a specific application. This way you can demonstrate how to quickly look for relevant information, which I think is the #1 skill for reading datasheets.
How about this:
- I create a meta thread here where everyone is welcome to post contents, feedback and proposed changes.
- The question of the meta thread should contain a continuously updated draft, which everyone can leave feedback to for at least a couple of weeks.
- Then I create a Paper category post as self-answered Q&A in my own name, with a link to the meta post.
- If new proposed changes are posted on the meta thread, I'll get notified by the site and then I can update the Paper post accordingly.
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