USB C vs type B micro for a new design. - Page 1
Forum section: electronics / projects

author: Fflint
author_rank: Frequent Contributor
timestamp: January 03, 2025, 02:39:17 pm
content: I'm designing a device I'd like to keep using 10 maybe 20 years from now. This thing is not going to be unplugged or moved often. If it was there would be no hope at all of achieving this lifetime. I need a capable uC inside with a USB interface to talk to a PC. I decided to use rp2040. This will be in form of a rpi pico with a USB B Micro connector or tiny2040 which is the same chip but with USB C.I have to choose based on the connector because other benefits/diosadvantages cancel out. Now USB C is a clear personal preference for me. The connector seems a lot more robust, but it may very well be just a perception. The standard hasn't been around long enough for me to say for sure: yeah, USB C will last longer.I have drawers full of useless USB B Micro devices the only failure in them being the connector. I have my own share of frustration with that connector, but it is useful to remember it first entered the market in 2007. That is 18 years... A very long time for an electronic device. And likewise I have some devices from that era that continue to work fine.So I'm not sure which one to choose and I decided to post here. Which would you choose and why? Do you have any data backing it up one way or the other? Please note I have to choose one of these two existing devices. I have no way to use a more robust version of a connector. It is what ot is if I choose one or the other device.Also, this device is just for me. It will not be sold. I don't have to consider other people's preferences.What would you do?

author: PGPG
author_rank: Frequent Contributor
timestamp: January 03, 2025, 03:12:02 pm
content: Quote from: Fflint on January 03, 2025, 02:39:17 pmMy opinion is that EU forces to use USB-C as supply of everything (including laptops) under the influence of some lobby of manufacturers who want the devices not to be too durable.Have in mind that in USB-micro you have 5 pin contacts and in USB-C 24 pin contacts.A month ago I have read (at Usenet electronic group) that someone found thrown away laptop and the only failure was USB-C. Laptop didn't had any other way to charge its battery. Now someone writing it is the happy owner of a relatively new laptop (older ones had normal round power connectors).

author: langwadt
author_rank: Super Contributor
timestamp: January 03, 2025, 03:20:03 pm
content: Quote from: PGPG on January 03, 2025, 03:12:02 pmnever let a chance to make up a conspiracy theory go to waste ..

author: mikerj
author_rank: Super Contributor
timestamp: January 03, 2025, 03:39:18 pm
content: Quote from: PGPG on January 03, 2025, 03:12:02 pmDid the laptops with round DC plugs have a different way to charge the battery? Anything can be broken with enough abuse, but USB-C connectors have proven robust, more so than micro-USB IME. It also provides way more functionality; multi-voltage, up to 240W power capability, video, audio etc..

author: ejeffrey
author_rank: Super Contributor
timestamp: January 03, 2025, 04:20:14 pm
content: Definitely type C if those are your two choices.

author: ajb
author_rank: Super Contributor
timestamp: January 03, 2025, 04:38:38 pm
content: No question: USB C. It's the direction everything is moving, and with a lot of good reasons.Quote from: mikerj on January 03, 2025, 03:39:18 pmActually, my current laptop does! It came with a barrel-plug adapter, but will also charge at 100W via USB C. I don't think that's too unusual for higher power laptops of similar age, where they can operate on 100W but might be able to perform better/charge faster with the higher power adapter. I think higher power Mac laptops are similar, but with magsafe + USB? Now that 240W charging is available, I'm sure more laptops will go to USB C only for charging, but higher end laptops with multiple USB C ports could certainly allow charging from more than one port.

author: ejeffrey
author_rank: Super Contributor
timestamp: January 03, 2025, 04:39:33 pm
content: Quote from: mikerj on January 03, 2025, 03:39:18 pmNo, and barrel jack failure was a pretty common failure mode of those laptops too. My laptop has 2 USB type C connectors and either can be used to charge, so it is actually redundant.Apples long discontinued magsafe was probably the best in terms of ruggedness but it was power only. You can get magnetic disconnect adapters for usb C which are almost as good. I'd recommend them if you are going to use a laptop somewhere the cord might get tripped over.

author: coppice
author_rank: Super Contributor
timestamp: January 03, 2025, 04:45:55 pm
content: Quote from: mikerj on January 03, 2025, 03:39:18 pmThe robustness of USB-C is not too bad for such a tiny connector, but are you REALLY trying to say its robust when compared to the large chunky coaxial DC connectors were have had on laptops for the last 3 decades? Being multi-functional is not an advantage. Its a large disadvantage. I want to power by computer regardless of what I am doing with things like video and audio, not watch video as an alternative to powering the machine. I realise we are going to have nothing but USB-C power going forwards, but be realistic. Its a horrible compromise.

author: wraper
author_rank: Unknown
timestamp: January 03, 2025, 04:51:47 pm
content: Quote from: coppice on January 03, 2025, 04:45:55 pmGood implementation of USB type C is way more robust than 99% of barrel jack connectors. Good implementation of micro USB is very robust too. The problem is poor implementation rather than connector type.

author: coromonadalix
author_rank: Super Contributor
timestamp: January 03, 2025, 04:52:55 pm
content: i would get rid of the micro usb ... but in industrial applications i love the B model, yeah big and clunky but solidseen some ripped off usb-c, lots of ripped micro usb, to play safe you could use chassis mounted ones just in case ... we dont use the micro on our new designs, too much problemseven with good implementations, clients are ...........as for Apple if i recall, they were pressurized by the europeans to use only the C, bye bye lightning and others, who where a pain in the ... still they sell genuine C for $$ pff because on some cheap ones, the apple carplay disconnect many times, good ones = no problems

author: coppice
author_rank: Super Contributor
timestamp: January 03, 2025, 04:58:51 pm
content: Quote from: wraper on January 03, 2025, 04:51:47 pmIf this like communism? Its never really been tried? I've never seen a USB-C that offered much robustness.

author: wraper
author_rank: Unknown
timestamp: January 03, 2025, 05:03:42 pm
content: Quote from: coppice on January 03, 2025, 04:58:51 pmReally? Somehow they usually last for years of everyday abuse. Only poorly designed device models have widespread problems with them. BTW broken barrel jack in laptop is not rare at all.

author: coppice
author_rank: Super Contributor
timestamp: January 03, 2025, 05:13:14 pm
content: Quote from: wraper on January 03, 2025, 05:03:42 pmOne big advantage of USB over barrel jacks is they plug in at both ends. Barrel jack cables are normally captive at one end. This means if the USB plug is weaker than the socket any damage is usually to the plug, and you just replace the inexpensive lead, rather than damage the expensive appliance. In the early days of micro-B this used to work fairly well, and it was usually just the lead which needed to be replaced. Over time it seems like they made the plugs tougher, and I saw more and more damaged appliances (phones and tablets, mostly). My early experience with USB-C was tainted by some poor implementations, which didn't stake the connector in place well enough, so solder connections were broken with quite modest bumps. I think they have improved, but I'm not sure the picture looks that rosy even now.Some notebooks had pretty flimsy barrel jacks, but serious business models, like the Thinkpads, had really chunky ones that were very hard to break. Lenovo changed to something that looked like a USB-A socket, but they were still pretty robust. Now they use USB-C, and you need to take considerable care.

author: ejeffrey
author_rank: Super Contributor
timestamp: January 03, 2025, 05:25:56 pm
content: Quote from: coppice on January 03, 2025, 04:45:55 pmYes.QuoteIt's pretty nice that when I plug my laptop into a USB-C monitor it also provides power? Also if it connects USB peripherals at the same time? It's fine if you never do that, but pretending like that isn't a huge, huge advantage is pretty dumb.Many laptops have multiple type-C ports so you can use one for charging and one for data if you want to. Or two for data. Or one for power input and one to connect to an external hard drive that also requires power. Replacing a DC-only jack with a USB-C port provides _vastly_ more capability as long as you don't just eliminate the port -- which is also an advantage for people who want to save size and cost by having fewer ports, an option that wouldn't exist without type C.

author: Someone
author_rank: Super Contributor
timestamp: January 03, 2025, 09:28:00 pm
content: Quote from: ejeffrey on January 03, 2025, 04:39:33 pmDiscontinued? ... no, their current power input method on all their shipping laptops.Quite the opposite. And like mentioned above, in addition to power input on all the thunderbolt ports so full redundancy.

author: ejeffrey
author_rank: Super Contributor
timestamp: January 03, 2025, 09:42:28 pm
content: Quote from: Someone on January 03, 2025, 09:28:00 pmHuh. Apparently they discontinued it from 2016-2021 and then brought it back? After reusing the name for their wireless charging system for phones? My wife's macbook only has USB-C, the one it replaced had magsafe. I'm glad they brought it back.

author: Konkedout
author_rank: Frequent Contributor
timestamp: January 03, 2025, 09:43:30 pm
content: Yes!! My impression of USB-C is that it is too fragile for larger devices (such as a laptop.) When I bought this Dell 2+ years ago, I looked for one with a barrel power connector. Unfortunately they now use a smaller diameter so I need a (size only) adapter in order to use my older power adapters. But I think I would continue to favor a laptop which uses a barrel connector for power instead of USB-C.

author: Buriedcode
author_rank: Super Contributor
timestamp: January 03, 2025, 09:45:54 pm
content: Yeah, every time a thread like this comes up you can people who claim USB-x connectors are weak, but either don't have any examples of "common" failure, or only provide examples of extremely cheap and poorly implemented products. Then there's the "planned obsolescence" folks. A universal connector for chargingisbetter for the vast majority of consumer goods, which is why there has been a push for one, rather than the drawers full of "chargers" destined for landfill. It makes perfect sense, but isn't meant to replace all possible connectors for all situations - you don't find USB-C on equipment on a factory line would you?I started switching the USB - C connectors in the middle of last year. I provide dual cables (USB-MicroB with C adapter, or visa versa) to customers who have older designed micro-B equipment.Now, for the record, I don't produce/repair any industrial gear that uses USB, only light-duty stuff, so I rarely see connector failure. Time will tell but so far I haven't noticed much of a different in usage, except the obvious orientation thing no longer being a problem. Given how small the construction is, I am surprised it isn't fragile, its quite impressive.Edit: just to carify, I'm asking folks if theybelieveUSB-C connectors aren't reliable, or have they actually experienced higher failure vs DC barrel jacks in laptops? Because one is speculating, the other is objective.

author: thm_w
author_rank: Super Contributor
timestamp: January 03, 2025, 10:20:28 pm
content: Quote from: coromonadalix on January 03, 2025, 04:52:55 pmB is good for industrial/rugged product agreed, if you have the space and either using for yourself or including a cable with the product.micro B and mini B are garbage.

author: wraper
author_rank: Unknown
timestamp: January 03, 2025, 10:28:08 pm
content: Quote from: thm_w on January 03, 2025, 10:20:28 pmUSB B is probably the worst and the least rugged out of all USB connector types. It's holding on PCB just by two shell terminals with a bit of support from backside pins. But its SMT variant is borderline criminal.EDIT, I just took PCB with USB B, wiggled the plug from one side to another with medium force about 20-30 times and it just broke off. If it was SMT, even 1-2 times could be enough

author: coppice
author_rank: Super Contributor
timestamp: January 03, 2025, 10:31:32 pm
content: Quote from: thm_w on January 03, 2025, 10:20:28 pmI think B can be good. I've never noticed anything about the design that looks bad. However, the implementations tend to have problems. I've never seen one 10 years old that hasn't corroded to the point of having contact problems. You can clean them up, and improve the contact stability a bit, but they are still going to be quirky from that point. Its easy enough to replace a lead, but the degraded socket on the equipment is a PITA. Maybe if you live in a very dry climate this doesn't happen so much.

author: coppice
author_rank: Super Contributor
timestamp: January 03, 2025, 10:38:34 pm
content: Quote from: wraper on January 03, 2025, 10:28:08 pmMost SMT connectors are borderline criminal. The only connectors I've used which avoid all through holes and are fix in a robust manner are recent USB-C connectors that sit in a recess in the PCB, and are thoroughly soldered right through the recess. Some of those are really well supported by the board, and tracks won't just rip off the surface with a small bump. SMA coinnectors are the dumbest surface mount connectors I've experienced. They might be OK with angled SMA connectors on the lead, but people use them where long aerials are screwed into them, and the strain is massive.

author: SiliconWizard
author_rank: Super Contributor
timestamp: January 03, 2025, 10:39:54 pm
content: I hadn't heard of anyone favoring USB micro-B to USB C for a good while. Entertaining.There is one thing that makes micro-B, not "better", but easier: if you want to implement USB OTG (dual role). It's just one pin to handle with USB-B. With USB-C, if you want dual role, you'll have to use a dedicated chip (or a MCU that supports handling CC1/CC2). In terms of robustness, some micro-B connectors are ok, but many are pretty bad. USB-C is sturdier and all connectors I've seen have 4 anchor points.And, whether one "likes" it or not, micro-B has essentially disappeared, so going for that for any new design doesn't make much sense.

author: ebastler
author_rank: Super Contributor
timestamp: January 03, 2025, 10:48:48 pm
content: USB-C, no doubt. I would not worry so much about durability of the connector, especially if you don't expect to plug and unplug it a lot -- but rather about availability of a compatible, working power supply and cable 15 years from now. USB-C clearly wins on that front, since micro-B is already outdated today.

author: coppice
author_rank: Super Contributor
timestamp: January 03, 2025, 10:50:27 pm
content: Quote from: ebastler on January 03, 2025, 10:48:48 pmIn 15 years it will properly be hard to find USB-C leads. We'll be on USB-D or USB-E by then.

author: SiliconWizard
author_rank: Super Contributor
timestamp: January 03, 2025, 11:09:22 pm
content: Quote from: coppice on January 03, 2025, 10:50:27 pmWell, you know USB-C is going to be the last ever version of USB connectors. Just like Windows 10 was going to be the last version of Windows.

author: thm_w
author_rank: Super Contributor
timestamp: January 03, 2025, 11:56:28 pm
content: Quote from: wraper on January 03, 2025, 10:28:08 pmThrough hole only for user connectors, no SMT pads. I would consider the USB C with tabs to be good through hole.But yes good point only has two tabs, not sure why they don't have them with four.You can get a panel mount version or wrap the enclosure around the shell to try to reduce excess force:https://support.bradyid.com/servlet/rtaImage?eid=ka04V000001E8V9&feoid=00N3A00000DGCTR&refid=0EM3A000001hxoY

author: WillTurner
author_rank: Regular Contributor
timestamp: January 04, 2025, 01:04:17 am
content: Quote from: Fflint on January 03, 2025, 02:39:17 pmAll connectors are bad, some worse than others. Wouldn't it be excellent to design them out?You have chosen the RP2040. Excellent choice BTW. Raspberry offer a couple of Pico solutions with a wireless variant for example. There are many third party implementations as well. Furthermore, Raspberry have provided an upgrade path in the RP2350. You can anticipate a lot more to be on offer in your twenty year project time-frame. The variant of USB connector is not going to be the most important long term issue you face.Now, this is your project, and you have complete design authority. You could work from the principle that the connector you are really designing around is the 40 pin Pico footprint (one row wider than the DIL package). So your basic "connector" could be two 20 pin DIL sockets, and then you can reuse and upgrade the CPU over time. Or you could use the castellated mount, and make the CPU disposable, avoiding the connector problem altogether.Next, if the USB connector is for initially programming the device (not for communicating with the host, or a keyboard/mouse implementation), then you could try self-hosting your software environment. I really like lurk101's unsupported P-Shell which has a limited RP2040 C Compiler. Forth or Basic would also work. RP2350 has booted Linux I think, but hey, early days. What you can anticipate coming real soon now, is a non-MMU Linux build, with standard tools (like cron!), which will of course, have to fit into the more limited RPxxxx CPU. You will also go down the path of implementing some kind of terminal. Either serial (GP0/GP1 are commonly chosen), or through one core doing VGA or HDMI. The RP2350 has a dedicated DVI/HDMI peripheral on board.If you are thinking of powering the project via USB, you would shift to bringing power in using a P-MOSFET to VSYS as described in the RP2040 datasheet.Now, here is the real problem ... you are going to put this design on a PCB, right? It will be stand-alone, self-hosting, with a built in ASCII terminal, power supply, and some custom peripherals. Believe me, you won't get it right first time. You are looking at designing a series of boards.When you encounter a problem, you bodge a solution, fix your schematic, upgrade your board design, and spin another hopefully reusing some components, and all of your software.This family of boards (over time) has to live somewhere, and you will want to reuse your enclosure. Since this is a 20 year endeavor, you could think about making your board the front panel in a 3U rack which is about 130mm tall. Hopefully this will eliminate your space restrictions.Now, you could already do most of this project on a much more capable CPU with gigabytes of storage, and a Linux development environment. I don't imagine cost is much of an issue. Probably the real issue is power consumption, and the RPxxxx are a couple of orders of magnitude better in that respect. A dumb micro has always been low power of course. The really exciting thing that has changed I think, is that excellent software is moving down into the micro-controller world.

author: magic
author_rank: Super Contributor
timestamp: January 04, 2025, 09:53:37 am
content: Quote from: coppice on January 03, 2025, 10:50:27 pmElectric vehicles will definitely require more power than USB-C provides.The future is a coaxial connector which can be rotated any way and carries data and three phases of mains power through the central conductor by means of frequency multiplexing.

author: SiliconWizard
author_rank: Super Contributor
timestamp: January 04, 2025, 10:24:04 am
content: Quote from: magic on January 04, 2025, 09:53:37 amThe kind of connector I posted here:https://www.eevblog.com/forum/chat/stock-electronic-image-fails/?action=dlattach;attach=2472967;image

author: Fflint
author_rank: Frequent Contributor
timestamp: January 05, 2025, 10:21:49 am
content: Wow, I was gone for a day and we have 30 replies. Lots I really would love to reply and discuss the details with. I doubt anyone will get through the resulting wall of text, but here goes.First let me repeat, I'm choosing between two already made rp2040 modules of which one has a usb B micro and the other has a usb C (standard rpi pico vs tiny2040). I have no way to choose THT over SMD. Both boards use a connector that use THT for two outside pins.So we're not talking about USB B by itself, nor it is only about power (I believe also mentioned in op) so a discussion about barrel jacks is beside the point (I love well made barrel Jack's BTW, I wish they kept them). The connector is to communicate between the board and a pc/laptop or whatever other host device we may be using 10 years from now. There is no need for OTG host on the rpi pico side.Yes, there are boards with a power supply (3.3V) and lots of relays this will control. It is a simple device that will run sequences of relay activities in response to pc commands. It will sit within a device (but a cast metal enclosure is provided due to adverse RF environment) and it will get +12V (and -27V, don't ask why) so no need to design AC supplies or have the usb be main power source.A person asked about projected plug in cycles, it will be minimal, after initial work and setup is done (let's say 100 cycles) I don't expect more than few cycles per month. But the cable may be tripped over, yanked, etc as it will go to a PC next to a large cabinet. Also I don't believe these connect/disconnect cycles quoted by manufacturers one bit.What complicates this even more is the fact all the devices I own that failed (with usb b micro)are very cheap Chinese things you'd buy in a dollar/euro store, while if I look at everything that has a real brand I ever bought with a USB B micro, I had only one failure (on a raspberry pi zero that was unplugged /replugged dozens of times a day. Few examples of good ones: Kindle paperwhite I bought the moment I saw one in 2013. Still going strong despite lots of cycles. An sd card reader I have had as long as I remember , most of mobile phones before usb C and so on.On the other hand the few USB C failures I experienced were with expensive, well made devices, for example Samsung S7 and S8 phones, a very expensive Dell XPS laptop a client sent me half a way across the world for remoting into their network had its power supply plug damaged by the slightest bend. They sent a new one, but I didn't want the old 120W PSU to go to waste so I disassembled the plug under a microscope and I found a cracked (or cold, who knows) solder joint on one of the pads of the plug.Now I'm not claiming based on these few examples USB B micro is better. I'm saying I don't know, and I do not trust the marketing depth numbers. The EU initiative to standardise the power/accessory connector is just that. To standardise, one everyone can agree on doesn't have to be the best. It very well might be, but IDK.Quote from: WillTurner on January 04, 2025, 01:04:17 amIt really is a simple device. Some would say even rp2040 is an overkill. Using a real SBC would be an egregious overkillI like the simplicity of just a micro. Now with micro Python development is even faster. The only reason to add a real SBC for me could be to add networking capability which would a nice thing, but it is in a very adverse RF environment so it would have to be wired Ethernet. While do consider Ethernet a superior connector to both of these tiny USBs the added complexity of maintaining yet another OS stack is not worth it to me.There is no need for a terminal for the user. Commands will be sent via USB emulated serial from the pc.All of power supply is one AMS1117-3.3 plus few caps. Relay voltage (12V) is supplied to the device as well as -27 these relays will send to control the big device this will live in (currently there is a box with an 11 way rotary switch and a push button, a person walks to the cabinet, sets the rotary switch and presses the button momentarily now to achieve same control action, the device is expected to finish the action in 30s and provides a single line shorted to ground from -27V to confirm).Quote from: Simmed on January 03, 2025, 11:04:02 pmNone of the ones that failed for me exceeded 2k cycles let alone 20k... (for both types!).Quote from: ebastler on January 03, 2025, 10:48:48 pmI still can get connectors and cables for ham gear made in the 60s of the previous century. I doubt USB B micro cables will become unavailable in my lifetime (hopefully I have about 3~4 decades left). You might mean "available " as in pop into your local pc store and get it over the counter as opposed to order it and wait days to have it arrive. Yes, that would be a valid point if this wasn't USB we're talking about :-) my local pc shops still carry USB A cables...so I think they will continue to have B micro.As for power supplies, there is a misunderstanding here. There is no need for a psu.Quote from: Buriedcode on January 03, 2025, 09:45:54 pmBut we're not comparing barrel Jack's to USB. We're also not talking about high power (100W etc) requirements. This is about basic serial emulation over usb. I gave my examples of USB C failures above.Quote from: SiliconWizard on January 03, 2025, 10:39:54 pmI'm making this for myself, not "the public". I have a lot of old gear. One could argue the equipment and connectors I have that are 40+ years old is still functional precisely because it is so old and none of the kit made now is like that. So I stead of building my device hoping to use it for decades I should make it modular and expect to replace the uC and the cable every few years. ... I'm making It modular ,but I REALLY dislike non soldered connections for low voltage stuff. Corrosion and vibration ,even just from fans, or small motors makes it unreliable. With over a dozen 3.3V control lines putting it in a socket is asking for trouble, but re-soldering can be done too.So while I am planning for the worst (swapping the uC board) I hope for the best.Quote from: Buriedcode on January 03, 2025, 09:45:54 pmSee my examples above. I'm not claiming usb C is unreliable. But I'm claiming we may not have enough data to say either way while we'll made USB B micro might be "good enough " for this?To be honest so far I haven't read anyone making a convincing claim one way or the other other than it being more modern etc. Modern is not always better. There are plenty of examples , but let me name one. The latest spacex space suits vs old NASA "bulky" ones. The new ones are sleek, they look cool, but they lack proper thermal management (so they had to do the EVA in the night side and still got uncomfortable hot), they lack micrometeorite protection (so they had to open a hatch and use it as a shield), the visor is optically bad looking like cheap plastic (we all saw internal camera feed) and you can't turn your head and look aside because the visor is only to the front. I could go on (umbilical on the leg makes sense inside the aircraft, definitely NOT when you're trying to pull yourself back to safety in an emergency ), but this post is long enough already.If anyone read that far thank you.

author: ebastler
author_rank: Super Contributor
timestamp: January 05, 2025, 10:49:33 am
content: In other words, you had made up your mind even before writing the original post, since you "feel" that the micro-B connector "might" be more reliable?

author: Kurets
author_rank: Regular Contributor
timestamp: January 05, 2025, 11:29:15 am
content: I'm on the "USB-C for everything is a mistake" my mlst recent work laptop was a Dell desktop replacement "luggable" which was fitted with only three USB-C ports and headphone jack. The worst laptop I have ever had to use in many ways, and the USB-C connectorts were definitely part of it.I got the laptop new, and after just months I had constant issues where a slight movement of a cable would result in disconnected devices etc. Charging had issues where it sometimes did not recognize the lead being plugged in (presumably failed communication with the brick). Add to that they you are forced to use adapters for any legacy device which add more leverage to what feels like a very unreliable connector, or the protocols implemented are a bit too sensitive to poor connections.I know anecdotes are useless, and I know a lot of people who have zero issues with USB-C. But to me it is not preferable to the older styles, not that there is much of a choice going forward.

author: wraper
author_rank: Unknown
timestamp: January 05, 2025, 11:47:10 am
content: Quote from: Kurets on January 05, 2025, 11:29:15 amFeels. Also it's more robust than most of type A connectors.QuoteWhat about changing the cable? Unlike in shitty A/B types, springy contacts are on the cable side.

author: PGPG
author_rank: Frequent Contributor
timestamp: January 05, 2025, 01:42:34 pm
content: Quote from: wraper on January 05, 2025, 11:47:10 amI have got post-lease DELL laptop with USB-C supply. I didn't noticed any problems yet, but I connected it charger to it may be twice (it waits for time to be setup by us from beginning and then replace my main working desktop PC to get possibility of taking my PC with me if needed).Changing the cable alone seems to me not possible. It looks that cable at AC Adapter side is permanently connected, even it looks like 90° plug. I tried to remove the alleged plug, but my fingers hurt and I achieved nothing. You can find ZF-20325 adapter photos.Quote from: Fflint on January 05, 2025, 10:21:49 amRF environment suggests to have galvanic isolation what Ethernet has 'by default' while USB not.

author: Njk
author_rank: Frequent Contributor
timestamp: January 05, 2025, 04:43:35 pm
content: A change not always driven by a necessity. For some folks, a bright and colorful "New" sticker is very attractive because to be with trend is a strong motivation. The enterprising people are well aware of that and will keep inventing more useless new things until this activity is banned by an ecology-obsessed anti-democratic governments.If the good old barrel jack is no more acceptable for every progressively thinking customer, invent a square power jack. Something that looks like the USB Type B connector with a square center pin. It can be mated with the plug in four different ways each of which leads to the same result. So it'll provide the customers with even more freedom and diversity. It's very important to make it such that each the way can be clearly identified. That will allow customers to unite in groups based on the preferred way, which is the best one while any other way is wrong. Obviously, a square jack is more difficult to manufacture than a round jack so a higher price tag will be accepted by the public. So everyone will be happy.

author: Buriedcode
author_rank: Super Contributor
timestamp: January 05, 2025, 08:26:28 pm
content: Quote from: Njk on January 05, 2025, 04:43:35 pmIn other words - create yet *another* standard only adding to the vast number of different vendor connectors that standardisation is meant to reduce? (insert relevant xkcd comic here). I don't think anyone in this thread has claimed that USB-C connectors are great for every application, and reducing E-waste isn't just about enviromentalism - its an inefficient use of resources, takes up space in peoples homes, costs more to the consumer.This entire thread is comparing USB-C to USB micro B connectors for new designs. Sure some *feel* that the newer connector is unreliable, or that it's some kind of push to change, which apparently is a bad thing, but ultimately all that is meaningless, we're engineers - it depends on what the OP's customer uses, or wants. If they only have USB micro B cables, and expect to use the product for a few years fine. If they want it to be used for 10 years, then why would you use a depreciated standard? But if it just sits in a corner, being used once a year, and has a bunmch of USB cables next to it, it doesn't matter.I'm amazed how people can take something as practical and arguably politically neutral as a USB connector and turn it into some kind of conspiracy or ideology?Edit: If your application requires you constantly pluging and unplugging (several times a day, no-one charges their laptop that much) then consider what previous replies suggested - magnetic USB cables, or better yet, design something that doesn't require constant plugging/unplugging USB. If you're worried about mating cycles, and want them to be above say 5k, what kind of application is that?! (once a day for 14 years, or 14 times a day for a year). I would argue that existing solutions won't survival those mating cycles.

author: wraper
author_rank: Unknown
timestamp: January 05, 2025, 08:34:23 pm
content: USB type C is certainly more robust than micro USB. Also it's the first USB connector variant that covers all use cases and allows to get rid of all prior variants. Micro USB does not have enough data pins but its USB 3.x variant is a weird monstrosity. 3.x USB type A/B also are a half-arsed attempt to add more pins.

author: mikerj
author_rank: Super Contributor
timestamp: January 06, 2025, 12:27:18 pm
content: Quote from: coppice on January 03, 2025, 04:45:55 pmWhen I use my laptop at home I put it on a stand and plug in a single USB C connector. This not only powers the laptop (and charges the battery if needed) but immediately connects my external monitor, my headphones, my full size wired keyboard and a debug adapter, RS232 serial port etc for whatever I'm working on. The alternative is plugging and unplugging a whole bunch of different devices, including USB hubs etc.Everything is a compromise, but the USB C standard is a very well designed set of compromises IMO.

author: mikerj
author_rank: Super Contributor
timestamp: January 06, 2025, 12:34:11 pm
content: Quote from: Kurets on January 05, 2025, 11:29:15 amTo be fair this is more of a Dell problem, rather than a USB-C problem. My last work laptop was a 17" Dell Precision with an i7 CPU and the best I can say for it was that it was reasonably fastwhenit was working. Dell made a complete hash of the USB-C implementation, it was notoriously unreliable and the IT guys were absolutely sick of sight of them after a few months. Not a brand I would ever spend my own money on.

author: Jeroen3
author_rank: Super Contributor
timestamp: January 06, 2025, 01:04:37 pm
content: You can always choose the give the device a tail. A cable internally plugging in to the pico, and some strain relief with a hole in the enclosure.Then your problem mophs into: "What plug does the cable need, and what length?"The answer to the question, what cable will be ubiquitous in 10 years?USB-C -> USB-MiniUSB-C -> USB-CUSB-A -> USB-MiniUSB-A -> USB-CIs probably: USB-C -> USB-CNo cable at all, but Bluetooth is also possible, since there will be phones without any sockets at all.

author: ArchieAltz
author_rank: Contributor
timestamp: January 06, 2025, 01:18:17 pm
content: I'd personally add USB-C to the device since it's more common than USB micro B (haven't seen one in like 10 years and I'm 15 lol) . Plus AFAIK USBC is now standard in the EU so finding the USBmB will probably be harder to find etc.

author: peter-h
author_rank: Super Contributor
timestamp: January 06, 2025, 04:44:47 pm
content: I have just spun off a new PCB for my last project, replacing a micro-USB with USB-C. It is power only plus the two data lines IOW no special USB-C functionality.It is much easier to get USB-C connectors which are hard to break off the PCB (due to having through-board PTH solder lugs), than micro-USB which are pretty easy to break off unless they have similar massive through-board solder lugs.The reversibility of C is a bonus.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: January 06, 2025, 04:57:58 pm
content: C is also more amenable to using a snug cutout in the case to add mechenical support.Never forget to add those two 5k1 resistors though - about half the Aliexpress tat that I've got, even recently, doesn't have them, so they don't charge from true USBC power supplies. Some even have the footprints on the PCB for them.

author: ArchieAltz
author_rank: Contributor
timestamp: January 06, 2025, 05:10:00 pm
content: Quote from: ebastler on January 03, 2025, 10:48:48 pmAt that point I think just replace the connector

author: Njk
author_rank: Frequent Contributor
timestamp: January 07, 2025, 09:14:40 pm
content: Quote from: Buriedcode on January 05, 2025, 08:26:28 pmDon't take me wrong, I'm not a Type C hater. The new connector seems well designed to fit the intended application area (a small mobile devices) perfectly. It's an excellent replacement for the mini and micro USB connectors in new designs. But actually, it's for a quite small (although popular) class of applications. My point of concern is some hype around it, which can result an undesirable side effects and implications.Some brave hearts will start considering it as an ultimate replacement for every existing DC power connector where it's electrically suitable, because it's so cheap and available. Although it was not designed for that purpose. For a power connector, the electrical suitability is not a primary choosing criterion. There are many others. For instance, in construction, it's strongly advised to keep the signal and power wires separately. Not because of safety or interference concerns. Basically, it's possible to lay a power cable once and use it forever. You can continue to use it even when the wire color fashion changed. But when an existing device has failed, the chances are it's no more available for purchase while the new device requires new signal wires. So you'll have to lay the signal cables again just because of that. So any signal wiring must facilitate frequent changes. For a power wires, it's not a requirement and this is why there must be separate conduits for a power and signal cables.Another brave hearts seems provoked to start using this wonderful connector where no connector is appropriate. Consider the two designs of the same functionality (IR adapter for the Fluke DMM). The first design (image 1) looks good but it uses a small USB connector (the type does not matter). It's placed such that the cable's angular momentum will try to wrench the connector's body out of the PCB. In addition to creating inconvenience for the user. The connector will not last long, even if it's of an ultra-modern type. The other design (image 2) seems less cool but the goal was to improve the robustness and convenience by elimination of the unnecessary intermediate connector. There are less points of failure and it's more future proof as the cable and even the IF bridge board can be easily replaced. Definitely, this design can last longer. Yes, it's all for occasional use so the durability seems not a primary concern. But listen to the IT security specialists. They're arguing that today everything must be designed with the security in mind from the beginning. I can add that the durability must always be in mind as well. Regardless of is it a formal requirement or not. Because that creates a good habit in the engineers. Today we must learn how to manufacture less, not more. It's not always possible, e.g. food or a shoes for kids but for a lot of things it seems doable if each the thing will last at least for the user's lifetime. From that point, the best thing is not that running faster but that which lasting longer. One Ukranian guy once told me that the old English agriculture tools from the early years of 20 century are of high value for the local farmers, because the steel quality is considerably better.As for the standardization, it seems the idea does not work as designed any more. It's not a problem to develop a standard, the problem is to enforce the compliance. Each time a standard proposal feels by someone preventing them from making money, they start crying about setting obstacles to the innovation process, etc. No way to discipline them, their lobbies are well-funded and strong (especially in the US), so the only practical way is to satisfy all of them. Take the EV charging connector as an example. How many different types of the same thing are standardized by ISO?BTW it seems there are little formal standardization documents for the consumer-grade DC power connectors. In the Western hemisphere anyway. I'm aware of the one abandoned IEC standard for barrel jack connectors, but the dimensions are different and the types which are in wide use today (like 5521) are all informal, like GoPro mount. So we have a lack of standards indeed.

author: Buriedcode
author_rank: Super Contributor
timestamp: January 07, 2025, 10:52:46 pm
content: Quote from: Njk on January 07, 2025, 09:14:40 pmAhh OK so, its more use cases than the connector deseign/standard itself. Well yes, as has been stated many times, it was never meant to replace "everything", and I dont' think I have heard anyone or any company make such claims. This says nothing about the standard itself, more that people will mis-apply it.I also haven't seen any "hype" except perhaps in the maker community where there is a wide range of experience/education from professors, to tinkerers - not really a place to get solid data on connector applications. Or the worst place for any kind of technology information - youtube (sorry Dave) or tech journalists., where it isn't about engineering, its about sensationalism, likes, clicks, views. Again, doesn't count because thats pure opinion.Quote from: Njk on January 07, 2025, 09:14:40 pmWho?Quote from: Njk on January 07, 2025, 09:14:40 pmNot sure what agricultural tools (industrial use) have to do with USB connectors (consumer gear), but if your point is "they dont' make them as good as they used to" the answer is: they do, but they also make many cheaper versions, which people tend to use more, and fail sooner so they get a bad reputation. In the past there wasn't much choice of tools/applicances/products, so the ones that were made were made to a higher standard, these days there is a much broader range of quality (and therefore cost) to cater for different customer requirements/use-cases/budget.Also you're talking about surivivor bias - the old tools that used cheaper materials simply didn't last, so the only tools that have been in use that exist today are the tougher ones that had much higher build quality (and probably cost a lot more too).If you're making something that you expect to last 20+ years of constant use/abuse, then USB (connectors) just aren't designed for that, so its the wrong use case.Quote from: Njk on January 07, 2025, 09:14:40 pmAgain.. this is kind of a tangent. EV's are still an emerging market with many different manufacturers still trying to agree on standards. Are you suggesting that standardisation doesn't work because... a relatively new tech sector hasn't instantly agreed on a standard?I mean, I agree with you to a point, companies will always push against these things because it means they can't force customers to also purchase their proprietary accessories that are vital for the product's functionality, or aren't compatible with their rivals products. And in many ways this push-back is a sign it is needed.Also it is true that standards are often ignored/violated for more budget versions, but that doesnt' mean to say we shouldn't try to have a "standard" which has fixed specifications that "houlsdf" be adhered to. Again, if a product violates this, its the manufacturers fault, and they should be called out on it. I suspect on reasonably priced gear this isn't the case, but only for ultra cheap products that people buy and then unreasonably expect it to be of high quality.

author: Fflint
author_rank: Frequent Contributor
timestamp: January 11, 2025, 11:18:35 am
content: Quote from: Buriedcode on January 07, 2025, 10:52:46 pmDespite being slightly OT this answer is interesting for me (although constant use doesn't mean unplugging replugging all the time, also abuse will hopefully be limited to an occasional pull of the cable a person snagged). So let's say you need slow serial connectivity with a simple uC board(not a SBC). In an adverse RF environment ,but you control grounding, shielding and so on, so while galvanic isolation sounds like a good idea it is not really required (usb cables work fine). The increase in complexity in implenting something like rs-485 (extra pins on the uC while it already comes with usb-serial on board, extra converter for the pc, a part that can break in it's own right, and requires a usb connection and cable that will end up in the same adverse RF environment anyway - the entire pc is).It will be unplugged / replugged frequently only initially for the first week. Then it will not be touched probably more than once or twice a month.The connector is about data only, no need to deliver power.So what would you use if you're building this for yourself? There will be no more units, just this one , to take care of one problem.I considered rs232, but the adverse rf environment (this sits next to a very powerful HF RF amplifier) and the need to have another adapter made me not use it. I already said why I thought rs-485 is worse than usb in this case.I also considered Ethernet and purely from connectivity it would be my first choice, but I thought it requires a SBC, with a tcp ip stack and so on. Recently I found this rp2040 board with Ethernet called wizznet w5500. I ordered a couple to test. Perhaps I'll use Ethernet yet. Well see.So this covers the protocol/signalling, but what about the connector (staying with usb for now)? I briefly considered using a screw together round connector with 4 pins (like ones used for microphones on cb radios etc). If it was going into a car etc I'd probably do it, but it is an overkill for a stationary application that sits in a closed building .So there you go, I'm curious what else would you choose.Quote from: wraper on January 05, 2025, 08:34:23 pmDo you know if any evidence to support this? I don't care about other uses cases for this device. It just needs serial.Quote from: ebastler on January 05, 2025, 10:49:33 amNo ,I didn't make up my mind fully. I do think usb B micro may be more robust where it is not cycled all the time, but I'm open to be convinced otherwise. So far no one has said any good arguments for or against except an opinion here and there.I was hoping after so many years on the market there are some studies at least for the micro b.

author: Kjelt
author_rank: Super Contributor
timestamp: January 11, 2025, 12:53:17 pm
content: Have a USB-c laptop for work now for four years.One for the monitor kvm, one for network at home.On work one for all.No failure whatsoever in 4 years aprox. 1200 to 1500 matingcycles.Some cables at work do have failed in those 4 years.If I sometimes see how colleagues use it pulling it under an angle or jerking it onnthe cable instead of pulling on the connector.....Tell me which small cheap connector would survive that abuse.....

author: Buriedcode
author_rank: Super Contributor
timestamp: January 11, 2025, 10:09:48 pm
content: Quote from: Fflint on January 11, 2025, 11:18:35 amThen USB C will be fine - and use a magnetic cable if you're worried about the cable being snagged, or you're constantly plugging/unplugging during development. Unless your device/product is extremely light, it won't get pulled off the surface its sitting on.Quote from: Fflint on January 11, 2025, 11:18:35 amIf the distance is small, then I don't see why RS232 would be a problem - you would need a hell of a lot of interference to generate +/-5V on 1 metre of cable. And there is nothing wrong with adding extra load to the data lines as long as the drivers can drive it. The fact you've considered RS232 tells me the data rate is low, which opens up a few more options - including IR or even fibre if you want super galvanic isolation.You've mentioned a hell of a lot of standards/ideas: USB and various connectors, ethernet, RS232, RS485 etc.. and it sounds like you're worried about interference, mechnical reliability etc.. so what test have you performed? You can't predict all possible problems - in terms of interference tolerance, sure you can choose more tolerant standards (USB is pretty tolerant) with differential signalling, but ultimately you're not going to know how bad the situation is until you either measure it, or test something and measure the errors.Honestly, I think you're over thinking this. If it is so critical for reliability (is this a medical device?) then look at medical or military devices and how they're designed.Quote from: Fflint on January 11, 2025, 11:18:35 amAhh so its stationary, in a closed building, so it doesn't really need to be IP rated, and the lack of power delivery makes it much eaiser, but I think this is your issue - not that there isn't a connector that suits your needs, that there are so many you just can't decide. Don't let perfect be the enemy of good, I think you're over thinking all this.In some ways, a highly restrictive enviroment such as deep under water, or surrounded by stupid amounts of EMI make design decisions easier because the specs eliminate so many options you're left with only a few to choose from and test.Quote from: Fflint on January 11, 2025, 11:18:35 amAgain, how often are you cycling the connector? Even when I'm developing USB OTG stuff I don't think I plugged the USB cable enough to harm the connector - after a while I made a USB mux cable for that purpose, so it could be disonnected at the push of a button.I'm unsure you will find such a study, given the sheer number of different USB connector manufacturers (and cable manufacturers, because the cable will affect results). It does seem this is your primary concern, and if its just serial, then you only need 3 lines... XLR is pretty hardy (DMX and audio gear takes a real beating on sets) but I'm still confused as to why you want SO many mating cycles? From what I've seen USB connector failure is rarely from over-use, mostly acute damage - but again, a magnetic cable will solve both those problems.

author: Fflint
author_rank: Frequent Contributor
timestamp: January 20, 2025, 08:55:38 am
content: Quote from: Buriedcode on January 11, 2025, 10:09:48 pmLet me tell you about this Rfi environmentImagine 1.5m of 10 wires shielded with a braid and with a bunch of snap ferrites on it (wires not twisted as its not differential signalling, it is just used to control some relays by shorting to ground). Then it goes into a cast aluminium box(braid attached to the outside of the box), each wire has a THT 2nF capacitor to ground and went to a relay with the other relay contact to ground.Then, there was an npn transistor driving that relay getting a signal from 3.3V logic. (the base had just a THT resistor and a zener to protect the logic in case of transistor failure, power was 12V)There was enough RF picked up by this cable to induce about 2V on the bases of these transistors clicking the relays needlessly when the amp was doing it's thing(12V went via a separate coax, it's shield also terminated on the outside of the box, circuit grounds - relays, logic etc go to the inside of the box, the box itself screwed to the metal frame of the rack). The higher the frequency the worse it got (this is all <30Mhz BTW so "high frequency " is 29MHz here).I had to add two 100nF SMD caps to each transistor. One right between the base and emitter and another next to the zener before the resistor.Now the amp can achieve full output, unless it is mistuned ever so slightly . Then on the highest band it will still click.So my next device for the same rack also has inductors in the control lines (these are about 10cm long wires inside the cast aluminium enclosure).So Rs232 is completely out...Quote from: Buriedcode on January 11, 2025, 10:09:48 pmNo, not medical at all. It's only an inconvenience when it fails. But it is an ex-military device and it's built to a very high level of reliability I'd like to match with my accessories.In a way I'm already doing that to some extent. Using a cast metal enclosure. Shielding on all wires etc. If I continue to have problems I might have to go all the way with optocouplers on all logic control lines instead of wires, a pcb layout that allows one side of optocouplers shielded from the other and so on(I have these elongated rectangle optocouplers that could fit a copper foil shield in the middle - I hope there is no need for mu metal). Most people that use this device solder RF bypass caps on the other end of this 1.5m long cable too, but that makes the connection permanent (it uses a proprietary connector that happens to fit spade terminals). I'd rather it stayed detachable so I can pull the device out of the rack for maintenance.As it is now, it only clicks when mistuned(which is rare as it has tuning settings memory). Well see about control box no.2.However , if you know of some resources about medical/military design methods can you post them please ? I'd love to learn more.Quote from: Buriedcode on January 11, 2025, 10:09:48 pmYes, there is definitely a stupid amount of EMI.Quote from: Buriedcode on January 11, 2025, 10:09:48 pmAs mentioned before, initially it will be fairly often, couple of times a day for 2 weeks maybe. Then it will be quite rare. If it happens twice in a month it will be a "busy" month. I expect not to touch it at all.As you see I don't really need lots of mating cycles , I'm interested in connector robustness as a whole. Number of cycles is a kind of a proxy for this.However , I think you're right there aren't such studies. I've already built the device I was planning when I started this thread. I found issues (with EMI) and I fixed them (to an extent). I used micro USB, because I saw no difference between it and USB C while the USB micro board has more gpio (not that I need that extra gpio now).But, as this thread was getting more recent replies one person prompted me to do more research and I discovered an rpi pico with Ethernet that is very cheap (it still has usb micro on the other end). So I decided to use that for the next device I've just finished building yesterday.If I continue having EMI issues with the first device I'll also swap the pico in there with the Ethernet version.So I thought the choice is narrowed down to these two USBs, but Ethernet is actually an option too, and possibly a better one (well see how it stands up to same Rfi - I only have foil shielded Ethernet cable currently).