Favorite power connector for small boards? - Page 1
Forum section: electronics / projects

author: dcarr
author_rank: Regular Contributor
timestamp: September 08, 2017, 05:44:31 pm
content: I'm looking for suggestions on a small DC power connector to use on a series of internal development boards. In the past, I've used surface mount USB connectors, but this series needs an 8-12V input and thus a new connector. I'd like to make a small ecosystem including one or more central power supplies with multiple jacks and a series of power cables.Goals:- cheap and reasonably compact surface mount (TH optional) connector- good supply of ready made cables if possible (6-24")- decent mechanical retention (similar to USB or better)- <15V <2AIdeas so far:- use USB (micro/mini B) with non-standard voltage - seems "oops prone", but otherwise meets all requirements- 1394 connector/cables - less availability particularly for cheap short cables, otherwise good, maybe slightly expensive- barrel jacks - connector retention seems iffy, probably would have to custom make cables- USB C - expensive, tiny connectors, spec does allow for higher voltages- 3.5mm headphone - might work, have had connection reliability issues in audio applicationsWhat do you use for removable power connections on your boards?David

author: DaJMasta
author_rank: Super Contributor
timestamp: September 08, 2017, 05:53:18 pm
content: Is something like 0.1" header connectors with latches sufficient for retention? You can go up to a few pins per rail if need be for extra current handling, and they can be fairly compact (plus it's easy to jumper stuff directly in while testing).Could also look into the battery connectors for RC applications, not sure if there's always a good board mount connector, but something like the mini Tamiya or the Deans connector are build for power handling and small size, so could be an option.I usually end up with barrel jacks, header connectors (not locking, not really for external connections), or screw terminals. Haven't had a lot of applications that had to be external and where a barrel jack wouldn't suffice.

author: dcarr
author_rank: Regular Contributor
timestamp: September 08, 2017, 06:03:35 pm
content: Good idea on the 0.1" headers, especially if I could get some with a retention feature. I could probably get a crimp tool to make up the cables fairly easily.

author: max_torque
author_rank: Super Contributor
timestamp: September 08, 2017, 10:07:26 pm
content: How much, and how many? The buzz words of connector selection!There are now quite a few manufacturers with "industrial" style direct to pcb style mechanically latched or retained conenctors.If you're feeling rich, then LEMO is the go-to brand for small foot print high spec connectors, but the price is, er as reassuring as the solid and secure feel of their connectors!However, you might be able to find a halfway house in terms of cost in the industrial M8 or M12 series, for which pre-assembled link looms are also available:

author: bjcuizon
author_rank: Frequent Contributor
timestamp: September 08, 2017, 11:02:15 pm
content: How about some small molex connectors or this one:https://www.element14.com/community/community/manufacturers/teconnectivity/connectors/blog/2013/04/08/et-power-connector-system.The latter is small-profile and has good power handling. I'm not too sure about its cost though. But its good for board mounted interconnect.

author: thm_w
author_rank: Super Contributor
timestamp: September 09, 2017, 12:25:09 am
content: JST XH, its close enough to 0.1", easy to crimp yourself or buy. I see some SMD versions are available, but they don't look robust at all though.https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20170908161549&SearchText=xh+cable+2pBarrel jacks are a bit larger but easier to plug/unplug (so yeah easier to fall out potentially) and a bit more robust. Can get SMD versions.Premade cables are commonly available:https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20170908162305&SearchText=2.5mm+power+cable

author: ratdude747
author_rank: Regular Contributor
timestamp: September 09, 2017, 12:49:41 am
content: Perhaps Molex/Amp Mate 'n Lok (.200 pitch) connectors? As in the kind PATA 3.5" drives use. Extension cables and splitters are cheap and plentiful. Being a defacto (AFAIK) standard for 12 and 5v, you wouldnt be as likely to oops something. The only thing I don't know is if they make an SMD version.I'd personally avoid M12 and similar connectors. There's a few defacto 4 pin M12 standards out there for them and they're mostly 24v supply based (PLC NPN vs PLC PNP, also SMC fieldbus power). What does exist, being industrial, is pretty pricey ($30 a cable sort of pricey). Like say my Banner sensor tester; its powered by 3 9v batteries. You wouldn't want somebody using that on your boards, right?But anything with existent cables already has a standard, so you're going to likely have a potential oops if a compatible standard doesn't exist.

author: colorado.rob
author_rank: Frequent Contributor
timestamp: September 09, 2017, 01:10:28 am
content: Have you considered BNC for power? You could also do SMA. Either one would have enough current carrying capability, are cheap, and have a solid locking or screw-in connector. If these are not RF boards or are likely to need one of these types of connectors, it might be worth considering. For a less common type, the TNC connector would also meet the spec. I like BNC because a banana jack to BNC adapter makes powering the thing on the bench a snap.

author: NiHaoMike
author_rank: Super Contributor
timestamp: September 09, 2017, 01:25:43 am
content: You could use USB with Quick Charge to enable 12V with a compatible power supply, but I would go for the common barrel jack. Some plugs have built in detents for retention.

author: langwadt
author_rank: Super Contributor
timestamp: September 09, 2017, 01:38:07 am
content: barrel jack would be the obvious choice, a 12V supply with a barrel connector is practically a standard, Digikey has lots of ready made cables in all size and shapessomething like this is easy,https://image.dhgate.com/albu_241706678_00/1.0x0.jpg

author: sleemanj
author_rank: Super Contributor
timestamp: September 09, 2017, 01:42:02 am
content: For internal semi-permanent connections, or stuff without enclosures, JST XH, JST PH, or KF2510 (commonly seen in 3p as the "PC fan connector").KF2510 has the advantage that it will plug either into the proper "socket", or onto bog standard 2.54mm male headers if need be. JST XH and PH are better retained and smaller.XH (2.5mm) and PH (2.0mm) both have surface mount varieties which are pretty robust, as well as the pins they have two extra non-connected, for want of a better word, tabs, which get soldered down also. XH and PH are both very common connectors in all manner of things, pre-wired stuff abounds.If more current is necessary there is also JST VH which is 3.96mm pitch (why JST decided that XH and PH should be nice metric pitches and VH not be, I don't know).For external connections, you want something a bit bigger and easier to handle and if needing to panel-mount a socket tidily that may be a large influence on the decision. If it's 12v (tolerant) I wouldn't hesitate to use good old 5.5/2.1mm DC barrel jacks center positive. You can get twist-lock barrel connections, and screw-togethor ones also (waterproof types) although I don't know if that is available in panel mounts I've only seen them wire-to-wire.

author: colorado.rob
author_rank: Frequent Contributor
timestamp: September 09, 2017, 01:53:57 am
content: Quote from: sleemanj on September 09, 2017, 01:42:02 amInteresting. I didn't know that existed. Something like this would be great for a project I'm considering taking on.https://www.alliedelec.com/switchcraft-l712as/70214399/?mkwid=sQPlpyw7S&pcrid=30980760979&gclid=CjwKCAjw_8jNBRB-EiwA96Yp1oHw95_MG3o2ACZbAj_13hFKVWxYi6Unbv7xOrU8bTnuPF2m_tKj6hoCdr8QAvD_BwE

author: don.r
author_rank: Frequent Contributor
timestamp: September 09, 2017, 03:11:16 am
content: RJ45?

author: bjcuizon
author_rank: Frequent Contributor
timestamp: September 09, 2017, 04:11:21 am
content: Quote from: don.r on September 09, 2017, 03:11:16 amOh yeah, I just remembered now. I have already tried using those LEGO Robotics kits (I forgot the name) which are programmable and they use 2-pin RJ11 jacks and plugs for interconnect between their components. (like for example, between the motorized wheel and main controller.)So.....RJ11 might be something to consider.It has retention clips too.

author: don.r
author_rank: Frequent Contributor
timestamp: September 09, 2017, 02:53:43 pm
content: RJ11 has the advantage of being smaller which is great for tiny boards. RJ45 is more robust and can carry more current. Either will do depending on project requirements.

author: alank2
author_rank: Super Contributor
timestamp: September 09, 2017, 05:45:19 pm
content: If the current is higher, I'd probably be temped to use Anderson Power Poles:http://tinyurl.com/ycptyv67

author: bd139
author_rank: Super Contributor
timestamp: September 09, 2017, 05:54:03 pm
content: I use the molex latching pin headers. Not sure what the series is. They are 0.1" pitch. you can surface mount them on the board edge as well if you want. Tayda Electronics sell them by the bucket load.

author: bjcuizon
author_rank: Frequent Contributor
timestamp: September 09, 2017, 09:05:36 pm
content: Quote from: alank2 on September 09, 2017, 05:45:19 pmCould be, but his specs above says <2A..and it may be a bit bulky.