Want to make a special resistor value out of series and/or parallel resistors ?

[Chipguy]

Hey folks

For the purpose of narrowing down 2 or more resistor values in order to make one special value you need you can use either Electrodroid or this little Windows program from a guy from Finland.

Old URL:
http://koti.mbnet.fi/jahonen/Electronics/ResOptimizer/

Modified updated URL 21.11.2013:
http://koti.kapsi.fi/jahonen/Electronics/ResOptimizer/

Since I dont have an Android phone (yet) this is going to help me a lot
Just wanted to share what I found. Please feel free to reply and share what similar stuff you found.

[BravoV]

I believe that guy is one of the member here with nick ... Jahonen. 

[jahonen]

Yes, that is done by me. Nice if you find it useful. I myself tend to use it all the time

Regards,
Janne

[Six_Shooter]

Neat!

[Chipguy]

Yes, that is done by me. Nice if you find it useful. I myself tend to use it all the time

Yes, it is indeed very useful. I also like the configurability with the "ser" files very much.
For some reason something like this is a hard-to-find tool. If I wouldn't have found yours, I would have had to write one myself.
That would have taken hours or even days to do.

Thanks man !

[zx80nut]

Oooh - looks very useful. I'll download it now.

...the number of times I've taken the trial-and-error approach to get a value this will be a really useful utility.

Thanks.

Grant

[sleemanj]

My javascript based solver isn't quite so powerful as that but it does the job, I use it to calc "stacks" of parallel SMD resistors to achieve a value using only the resistors I have...
http://sparks.gogo.co.nz/resistor_paralleler.html

Wolfram Alpha is also pretty handy, for example: http://www.wolframalpha.com/input/?i=72+Ohm

[kripton2035]

I did the same (for mac os) 10 years ago ...

[Rufus]

http://www.eevblog.com/2010/01/07/useful-resistor-calculation-tool/

[Chipguy]

Thanks for all your replies.
There are some useful tools out there which all have their highlights.

I think I like Jahonen's tool the most.
The one for the Mac looks interesting too.

[LukeW]

There's a great little website tool I like to use here:

http://jansson.us/resistors.html

Not only does it choose series or parallel combinations of a couple of resistors, using standard E-series values, to try and meet a specified target resistance, it also does resistor ratio calculation choosing from standard E-series values, which is handy when designing opamp or voltage-regulator feedback circuits.

Personally I think a website applet is more appealing than having to download and install some binary on your PC... especially if it's Windows-only.

[Chipguy]

I found another use for the tool today:
Since there is a list of E-Series resistors to select from it also serves as just an E series standard value table.
Before that I used to have a look into a Wikipedia aricle every time.

Cheers
Chipguy

[codeboy2k]

I put all the links to the resistance calculators that were mentioned in this thread into the EEVBlog wiki  here : Resistance Calculators (wiki)

The Wiki doesn't get enough love