EIA E12/E24 values in Excel

[Andrew Larkin]

bit of Excel that may be useful to people.

 

I often need to find the nearest EIA E12 or E24 value (that is, stock resistor or capacitor value) to a calculated result for a circuit design.

 

Here is a self-contained Excel formula for the job.

 

For E12:

=(10^INT(LOG10(inputvalue)))*CHOOSE(ROUND(MOD(LOG10(inputvalue),1)*12,0)+1,1,1.2,1.5,1.8,2.2,2.7,3.3,3.9,4.7,5.6,6.8,8.2,10)

 

For E24:

=(10^INT(LOG10(inputvalue)))*CHOOSE(ROUND(MOD(LOG10(inputvalue),1)*24,0)+1,1,1.1,1.2,1.3,1.5,1.6,1.8,2,2.2,2.4,2.7,3,3.3,3.6,3.9,4.3,4.7,5.1,5.6,6.2,6.8,7.5,8.2,9.1,10)

 

I'll leave it as an exercise for the student to do versions for E48, E96, and E192.

 

[Julian Sortland]

Some R&D organisations hold both E24 and one of the higher series, as many of the E24 values do not appear in the higher series.

73,

Julian.

--
You received this message because you are subscribed to the Google Groups "Robots & Dinosaurs" group.
To unsubscribe from this group and stop receiving emails from it, send an email to sydney-hackspa...@googlegroups.com.
To post to this group, send email to sydney-h...@googlegroups.com.
Visit this group at http://groups.google.com/group/sydney-hackspace.
For more options, visit https://groups.google.com/d/optout.

--

====================================================
Julian Sortland, ALIATec, VK2YJS, AG6LE.

Ph:  0429 470 672

123 North Street
OBERON  NSW  2787
AUSTRALIA

[Gav]

For E12:

=(10^INT(LOG10(inputvalue)))*CHOOSE(ROUND(MOD(LOG10(inputvalue),1)*12,0)+1,1,1.2,1.5,1.8,2.2,2.7,3.3,3.9,4.7,5.6,6.8,8.2,10)

 

Very nice :-)

[John Slee]

On Saturday, 10 January 2015 07:00:51 UTC+11, Andrew wrote:

I often need to find the nearest EIA E12 or E24 value (that is, stock resistor or capacitor value) to a calculated result for a circuit design.

Somewhat related: I often find myself missing a weirdo value that I don't currently have. So I wrote a thingy to combine pairs of things I do have (according to a stock list) in order to fill the gap

There's a bunch of websites out there that do similar calculations (Javascript etc) also but they typically assume you have complete E48/E96/etc series on hand

https://github.com/indigoid/r-combine

John