Libraries parametric search options

Hello there,

Excuse for my ignorance on this topic, I was wondering: are there ways to execute parametric search inside the symbol libraries?
Alternatively, are there search patterns that can be used in the main search bar?

For instance, I’m looking for a 1 Ohm resistor in my library and here are all the matching results:

Any chance I can format my search to hit only 1 Ohm resistors and not all parts that contain the 3 keys “RES 1 OHM” in their description? Any documentation related to search patterns?

Also, is there a tool where one can sort library tables by symbol parameter?
For instance, showing all resistors in one big table, clicking on “Resistance (Ohms)” column would sort all resistors by resistance value.

Thanks a lot!

I generally use a system where the “SI prefix” (or unit for multiplier 1) replaces the decimal point. Which means a 1 ohm resistor is specified as 1R00. This means I have a unique search term for this value. (0.01 ohm resistor would be 10m0, a 10 k resistor is 10k0)


I also do not add every single resistor as a symbol to my libs. I use house part numbers as a pointer to an external database (ok its just a spread sheet) that then translates to the order number (this allows me to switch supplier or even exact part number without needing to change the schematic. It also keeps my libs rather small)

The “Choose Symbol” search box (I think that is the screenshot you’re showing, you cut of the title…) seems to search for loose keywords and parts of them. And it also seems to search in multiple fields such as the “Description” and “Keywords” fields. and search terms are separated by spaces.

Words also do not have to be complete or start from the beginning of a word. For example searching for “tentio” will find potentiometers. In your case adding the size of your resistor such as “0603” seems a good way to narrow down the results.

Using both “RES” and “OHM” is not very productive, as both search terms are likely to be common to all resistors.

Personally (and apparently most KiCad users) do not use completely specified schematic symbols for resistors. There are just too many for them. A resistor like “1.05k” suggests E96 or more, multiply that with your resistor size, etc.

The “1” in your search term is also very generic. It can be either in the value of the resistor (1k), the tolerance (1%), power (1/10W) or the size (1206).

If you search for the value field, you can narrow your search down much more. Try: “02FT1K0”.

Thanks @Rene_Poschl and @paulvdh for your responses.

I think I may not have been quite clear on my request.

Although it is nice of you to share your opinion on your own implementation of library management, dos and don’ts, productive vs not productive, etc. I was trying to find where can I learn about the details of the search mechanism in KiCad.

For this example (and I’m interested in general mechanism, not only this one), “RES 1 OHM” should only return any part which fields match exactly this sequence of words, not any combination of these 3 words or letters. This makes search request much too loose in my opinion. So it looks like there is no way to force the search to match exactly this sequence and that the parametric search feature I hoped for is nonexistent.

Thanks.

Euhm…
If you read the manual: Eeschema / Help (If you have documentation installed) then Chapter 6.4.1 “Find and place a symbol” explains the syntax for the search box, including wildcards and regular expressions and more.

Try replacing your spaces with dots (which represent any single character) in regex format. So try:
RES.1.OHM

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Haaa this is where the documentation resides! I did not know it was built-in KiCad and kept looking online :slight_smile:

For this example the dots are the solution, thanks @paulvdh

image

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This is a good approach desirable for Kicad system wide. The calculator input for regulator tab only accepts KOhm. A parser should unify all inputs not regarding if they go for library search or calculation or simulation input. All user entry like 1234, 1234R, 1.234K, 1K234, M001234 and 0M001234 should give the same results. Already anywhere in the bug list ?

I’ve been using the “SI prefix” to replace the dot also, and have done so for years.
Here in the Netherlands I grew up with it. Elektuur (now Elektor) has used this notation at least since the '70-ties, and still does so today.

Circuit Cellar does not. It uses the notation with dots such as 4.7k Even in the time they were getting strangled by Elektor.

EPE (Everyday Practical Electronics) mostly uses notation with dot (2.2k) but sometimes also uses the 2k2 notation.

Nuts & Volts is not consistent. It uses: 4.7uF 0.01uF but also 6K8 (even though SI says lower k).

In Odroid Magazine you’re more likely to find a software listing then even a fritzing “schematic”.

Olimex uses dots in the schematic of the A20-Olinuxino-Lime2 such as: 4.99k
In the Olimxino-2560 (Arduino clone, see: https://github.com/OLIMEX/OLIMEXINO-2560) they use combination of dosts and tolerances in the value field of the (KiCad !) schematic. For example: 6.8k/1%. Though I don’t like arduino, I do like Olimex. They even use a SMPS IC on their “arduino” clone!

A simple search @digikey verifies that they understand what a 1k2 resistor is:
https://www.digikey.com/products/en?keywords=1k2%20resistor

Same for Farnell:
https://nl.farnell.com/w/search/prl/resultaten?st=1k2+resistor

A few simple web searches for electronic schematics also finds mixed results, but the “2k2” notation seems to be fairly common.

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