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This datasheet for a mini dev board, as an example, denotes eg C1 as 0.1µF, and C6 as 10000pF, instead of 100nF and 10nF, respectively. This is something I've noticed in several datasheets at various times. Is there a reason some manufacturers would avoid the usage of nF as a unit in this manner?

Isaac Middlemiss
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  • I've often wondered this as well. It's not just datasheets--if you look at capacitor listings on Digikey or Mouser, many of them will list capacitances of "10000 pF" or "0.22 μF" instead of "10 nF" or "220 nF". – Hearth May 26 '23 at 01:21
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    Nanofarads are a relatively recent invention - when I was a lad we only had microfarads and micro-microfarads. – Peter Bennett May 26 '23 at 01:23
  • It may correspond to the print/markings on the capacitor. – user107063 May 26 '23 at 01:24
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    It is a historical thing. See: https://electronics.stackexchange.com/questions/245450/why-are-capacitors-often-not-labeled-using-engineering-notation-1-999 – user1850479 May 26 '23 at 01:25
  • I've always used uF and pF, and sometimes F in discussions, for over 60 years. For some reason, it seems like the industry coalesced around suffixes that differed by 10^6. I do not remember seeing nF being used at all back in the early days. – SteveSh May 26 '23 at 01:27
  • But, on the other hand units of time differ by a factor of 10^3 - s, ms, us, ns, ps, fs, etc. – SteveSh May 26 '23 at 01:29
  • Yep, seems like this is a duplicate, my google-fu was just off and those two questions didn't come up – Isaac Middlemiss May 26 '23 at 01:33
  • @IsaacMiddlemiss - Hi, Thanks for creating an answer to capture the information from the comments. Following the protocol explained on Meta here & here, I have copied the relevant info from comments and added links to the original comments & user profiles, to comply with the CC BY-SA license. I have also set it to "Community Wiki" so the answer's author doesn't get from votes from the answer (as it is an aggregation of info from other site members). The CW setting shouldn't imply easier editing here. Thanks. – SamGibson Jun 03 '23 at 19:49

1 Answers1

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The question was answered in the comments, so this answer was created to capture that information.

Comment by Peter Bennett:

Nanofarads are a relatively recent invention - when I was a lad we only had microfarads and micro-microfarads

Comment by Hearth:

It's not just datasheets--if you look at capacitor listings on Digikey or Mouser, many of them will list capacitances of "10000 pF" or "0.22 μF" instead of "10 nF" or "220 nF".

Comment by user1850479:

It is a historical thing. See: why are capacitors often not labeled using engineering notation ? (1-999)

Summary: It appears this is due to a historic naming convention, as described in this question and this question, with nanofarads being a more recent thing.

SamGibson
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Isaac Middlemiss
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