Connectors - Page 1
Forum section: electronics / projects

author: S185149
author_rank: Contributor
timestamp: October 31, 2017, 04:51:55 am
content: Of the thousands of connectors in the DigiKey web site, any recommendations on what to use for low power or signal connections? Most of the perf boards are at 0.100" pitch so that is one requirement.ThanksS18

author: tooki
author_rank: Super Contributor
timestamp: October 31, 2017, 06:41:26 am
content: You're gonna need to be a lot more specific about what you need. What (physical objects) are you connecting to what? What signals are they gonna carry? What environment? Use scenario?There's a reason there are thousands of connectors, you know!

author: KL27x
author_rank: Super Contributor
timestamp: October 31, 2017, 07:26:24 am
content: If you're using perf board to make circuits, you should be very happy with 0.1" header pins and female headers. I gots a jar of these things that lives on my bench. I use them at up to 1A without concern. At up to 3A if I'm ok with cleaning/replacing if/when necessary.

author: S185149
author_rank: Contributor
timestamp: October 31, 2017, 11:11:28 pm
content: Quote from: tooki on October 31, 2017, 06:41:26 amAs an example, I want a connector for connecting batteries to the board using 22-24 gauge wire. Would like to have some latching feature so it does not pull off easily. No harsh environment so it does not have to be water proof, high temperature or any of that. What would you recommend?Thanks,

author: ahbushnell
author_rank: Frequent Contributor
timestamp: October 31, 2017, 11:43:58 pm
content: https://www.digikey.com/product-detail/en/molex-llc/22-05-3021/WM4300-ND/26689

author: Mr. Scram
author_rank: Super Contributor
timestamp: October 31, 2017, 11:45:03 pm
content: Quote from: KL27x on October 31, 2017, 07:26:24 amThis may be an odd question, but regular pin headers seem to be a fairly popular choice for board to board interfacing. Disregarding high speed signals or huge currents, why would you pick other interfaces?

author: S185149
author_rank: Contributor
timestamp: November 01, 2017, 02:21:17 am
content: Quote from: ahbushnell on October 31, 2017, 11:43:58 pmThanks. Now I have a place to start.

author: mariush
author_rank: Super Contributor
timestamp: November 01, 2017, 03:15:24 am
content: JST have a bunch of series with various locking schemes, but few series are 0.1" ... they have a lot of series where the distance between pins is 2.50mm or 2mm ... 2.50 mm connectors with 2 pins or maybe even 3 pins would still fit inside holes spaced 0.1" (2.54mm) if the holes are big enough.See for exampleJST EH (9.8mm tall) :http://www.jst-mfg.com/product/pdf/eng/eEH.pdfJST XH (8.1mm tall) :http://www.jst-mfg.com/product/pdf/eng/eXH.pdfJST XA (with retention clip) :http://www.jst-mfg.com/product/pdf/eng/eXA1.pdfDigikey stocks them ... and you can even buy ready made cable assemblies, at least with JST XA :https://www.digikey.com/products/en/cable-assemblies/rectangular-cable-assemblies/450?k=jst%20xa

author: S185149
author_rank: Contributor
timestamp: November 01, 2017, 05:59:38 am
content: Quote from: mariush on November 01, 2017, 03:15:24 amThanks for the information.

author: tooki
author_rank: Super Contributor
timestamp: November 01, 2017, 11:05:40 am
content: Quote from: S185149 on October 31, 2017, 11:11:28 pmFor this, I have been using JST XH series from eBay, where you can inexpensively buy sets of both the board connector and pre-crimped wires with the matching plug preattached. Note, however, that as Marius said, these are on 2.5mm pin spacing, wheras normal perfboard, DIP ICs, etc. are 2.54mm (0.1") spacing. So a 2-pin JST XH will fit fine, 3 will work too, but beyond that it can be problematic. Just a limitation to be aware of.American connector vendors (Molex, Amphenol, etc) have similar products in 0.1" spacing, like the Molex KK that ahbushnell recommended. Certainly a good option, too.Other than that, for this type of low-voltage stuff, I use regular pin headers and "dupont" connectors all the time. (That's what eBay calls them. Legit distributors like Digi-Key use actual manufacturer designations of course, and just call them "headers" generically.) I always have male headers around in both straight and right-angle, and in single and double-row (though I use single row 99% of the time). The disadvantage to these is that the wire connectors are quite tall. JST, KK, etc are lower profile.For thicker leads, so far I've just been using PCB-mount screw terminals. But there are connector series for these applications, too.One downside to all these connector types is that most of them crimp to the wires, so you end up needing a stable of crimp tools, which gets spectacularly expensive if you use the name-brand tools.(I've stuck with cheap ebay crimp tools, which vary from OK to uselessly bad.)

author: mariush
author_rank: Super Contributor
timestamp: November 01, 2017, 01:01:26 pm
content: For standard 0.1" pins and headers and sockets, I used to order Harwin M20 series ... this series is Harwin's "generic 0.1" spaced pins and stuffhousings :https://www.digikey.com/products/en/connectors-interconnects/rectangular-connectors-housings/319?k=&pkeyword=&s=10810&FV=ffe0013f%2Cfffc03b8&mnonly=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25headers, female sockets :https://www.digikey.com/products/en/connectors-interconnects/rectangular-connectors-headers-receptacles-female-sockets/315?k=&pkeyword=&s=10810&FV=ffe0013b%2Cfffc03b8&mnonly=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25Rectangular Connectors - Headers, Male Pins :https://www.digikey.com/products/en/connectors-interconnects/rectangular-connectors-headers-male-pins/314?k=&pkeyword=&s=10810&FV=ffe0013a%2Cfffc03b8&mnonly=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25female contacts (for housings) :https://www.digikey.com/products/en/connectors-interconnects/rectangular-connectors-contacts/331?k=&pkeyword=&s=10810&FV=ffe0014b%2Cfffc03b8&mnonly=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25They're fairly cheap if you buy them in some decent quantity like 25pcs or more.As for crimping tool, I bought an Engineer PA-20http://www.engineer.jp/en/products/pa09e.htmlwhich is around 40-50$ depending on where you order it fromPA-09 is slightly better for thinner wires and tiny pins, but won't be as good for thicker cables like AWG18 wires you normally would have in power supplies. PA-20 can do AWG24 just fine, so shouldn't be a problem.Both tools are 2-step crimping tools, you can probably buy tools that crimp the connector in one step but i'm happy with mine , not crimping so many contacts that the 2 step process would be inconvenientThey can crimp pins for a huge amount of series, here's a chart for both pa-09 and pa-20 :http://www.engineer.jp/en/products/pa09_20applicatn_chart.html

author: S185149
author_rank: Contributor
timestamp: November 02, 2017, 05:29:12 am
content: I appreciate all the recommendations. Thanks.

author: jmelson
author_rank: Super Contributor
timestamp: November 02, 2017, 08:42:31 pm
content: Quote from: S185149 on October 31, 2017, 04:51:55 amFor single-row, Molex-style with gold-plated contacts on both sides are good. For dual-row, there are tons of ribbon cable connectors with .1" grid.Jon