Want to make a special resistor value out of series and/or parallel resistors ? - Page 1
Forum section: electronics / projects

author: Chipguy
author_rank: Unknown
timestamp: November 17, 2013, 02:12:35 pm
content: Hey folksFor 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 lotJust wanted to share what I found. Please feel free to reply and share what similar stuff you found.

author: BravoV
author_rank: Super Contributor
timestamp: November 17, 2013, 02:15:16 pm
content: I believe that guy is one of the member here with nick ... Jahonen.

author: jahonen
author_rank: Super Contributor
timestamp: November 17, 2013, 06:01:51 pm
content: Yes, that is done by me. Nice if you find it useful. I myself tend to use it all the timeRegards,Janne

author: Six_Shooter
author_rank: Regular Contributor
timestamp: November 17, 2013, 06:15:16 pm
content: Neat!

author: Chipguy
author_rank: Unknown
timestamp: November 17, 2013, 06:35:45 pm
content: Quote from: jahonen on November 17, 2013, 06:01:51 pmYes, 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 !

author: zx80nut
author_rank: Newbie
timestamp: November 18, 2013, 12:28:50 pm
content: 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

author: sleemanj
author_rank: Super Contributor
timestamp: November 18, 2013, 01:19:18 pm
content: 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.htmlWolfram Alpha is also pretty handy, for example:http://www.wolframalpha.com/input/?i=72+Ohm

author: kripton2035
author_rank: Super Contributor
timestamp: November 18, 2013, 02:21:07 pm
content: I did the same (for mac os) 10 years ago ...

author: Rufus
author_rank: Super Contributor
timestamp: November 18, 2013, 02:54:11 pm
content: http://www.eevblog.com/2010/01/07/useful-resistor-calculation-tool/

author: Chipguy
author_rank: Unknown
timestamp: November 18, 2013, 10:39:50 pm
content: 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.

author: LukeW
author_rank: Frequent Contributor
timestamp: November 19, 2013, 10:16:36 am
content: There's a great little website tool I like to use here:http://jansson.us/resistors.htmlNot 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.

author: Chipguy
author_rank: Unknown
timestamp: November 21, 2013, 11:14:04 pm
content: 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.CheersChipguy

author: codeboy2k
author_rank: Super Contributor
timestamp: November 22, 2013, 07:19:21 am
content: 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