Am I the only one who thinks that the physical connector standard for USB-A is inappropriate for its use? I have numerous laptop and desktop PCs that have one or more defective USB connectors. Some were damaged when the connected USB cord or device was bumped or jerked. Others failed for no apparent reason at all.
In the case of those that failed for no apparent reason, I suspect that the damage came from the cumulative result of numerous attempts to insert the plug or device upside down. In other cases, the little plastic backing plate and contact guide breaks off, leaving four unsupported and non-insulated pins in the opening, and rendering the port unusable.
The ubiquitous USB type A connector is also one of the most delicate and breakable devices.
Other forms of connectors work fine for years. I have one serial adaptor that has outlived several laptops, even after having been inserted and removed hundreds of times. For some reason I have never seen the cord end -- which would be easy to replace -- break this way. It is always the female receptacle buried deep within the computer that fails.
I have another issue with these USB connectors. There is no immediate visual cue for the correct orientation of the plug when it is inserted. There is no tapered “lead-in” to guide insertion of the plug. That means that half or more of the attempts to insert the connector will be unsuccessful. The male connector is upside down or slightly misaligned with the female connector half the time. I believe this contributes to the deterioration of that little plastic backer plate in the female socket.
I read this post with great interest waiting for the "aha" moment when I too could say, I experienced that as well. I have to say with all of the devices/laptops/desktops scattered around my house/home office, I have never, ever had a problem with a frail USB connector, despite the numbers of times I've connected/disconnected. I'm wondering if the USB connector is from a specific manufacturer or set of manufacturers and perhaps quality issues belies the problem rather than the actual USB-A connector standard.
I've never had a problem with a USB-A either, Beth. Though I've always felt uncomfortable with the leverage factor. The way the thin USB-A sticks out of a laptop makes me think that dropping the laptop just a few inches at the right angle would snap the USB right off. So far, I've been careful not to drop my laptops.
I've also never had a problem with USB connectors breaking, nor have I heard complaints from friends or co-workers regarding this issue. I wonder if this is a common problem for many or if there is some sort of wacky user error going on in the case of this author. In any event, the only problem I ever have is when I try to jam the connector into the slot, only to realize I have it upside down.
I agree with the upside-down problem, Jenn. In the posting, the user said you're going to hit it wrong about 50 percent of the time. I have a side-loading input in my laptop, so 50 percent misses are about right. Yet those misses don't seem to do any damage to either the USB-A connector or the laptop port.
I'll add my 2 cents to the clamor and say I've never had a problem with USB connectors. The fact that the author says it's the female end, inside the device, which tends to break makes this a major problem, since it's relatively inaccessible.
I was puzzled by the author saying there's no indication on the male plug regarding which side is up. Uh, you must have a Windows machine. Macs have always indicated which end of the plug is up with a symbol.
"The USB specification states that the required USB Icon is to be "embossed" on the "topside" of the USB plug, which "provides easy user recognition and facilitates alignment during the mating process". The specification also shows that the "recommended" (optional) "Manufacturer's logo" ("engraved" on the diagram but not specified in the text) is on the opposite side of the USB Icon. The specification further states "the USB Icon is also located adjacent to each receptacle. Receptacles should be oriented to allow the icon on the plug to be visible during the mating process".
Knowing this has simplified USB usage for me...all my PC's and Flash Drives, USB cables, etc adhere to this standard.
There's one part of the USB connector spec you left out that MAY help explain why many people have issues (not all; I haven't experienced any failures over many years of using USB. The connector itself has a lifetime requirement of only 500 insertion/removal cycles! That applies to both the board-mount and cable ends. Also, since most people (myself included) and OEMs use ONLY the cheapest possible cables, the quality isn't always the best, and may not meet even that modest requirement. I ran into this when an automotive OEM customer insisted on a 50K cycle life rated A connector for attachment of USB memory devices. I told them we'd be happy to comply IF they "directed a source" and PAID for the "superconnector!" Requirement went away.....
Andrew, thanks for the explanation. But that may still be partly a PC/Mac thing. My latest Mac is a few years old, I grant, but all my Macs to date have either had ports on the side where it's pretty obvious (laptops), or if they're in back (desktops) I don't change them often anyway.
The first time I encountered the blind mating problem on the back of a machine was with my first ever Windows computer, a laptop. The port was not only in back but also sideways, which struck me as pretty stupid.
I think all my USB-A connectors have the USB symbol on one side. When they're printed, the symbols are useful. When they are embossed, they are less so. And what's this about Mac's having the symbol indicating "this end up." All the connectors on my iMac are vertical. side by side, like dominoes on edge. And they are on the back. where they are not easily viewed. The old serial and parallel 'D' connectors could be oriented by feel, when it was inconvenient to get eyes on the target. Not so USB. I know, the form factor is smaller, but there should be a tactile method of determining orientation of the plug AND the jack.
That said, I've not had a USB connector or jack mechanical failure so far. My only USB failure was a big ouch though - with a powered hub that had a round power port that fit a 12V adapter just as well as it fit the included 5 volt adapter. A moment of carelessness and then, so much for the Zen mp3 player. Fried either its power supply or battery. We may never know.
rickgtoc, you must have a Mac newer than mine. I don't know when this changed, but for decades the ports were horizontal, so the connector on the end of each cable showed the embossed symbol on the top surface. One of Apple's myriad simple, elegant, graphic, and easy to understand solutions, making things intuitively obvious. Just like the (original, pre-OSX, pre-Intel) OS.
1) Yes, I am hard on equipment - I use this stuff for troubleshooting in an industrial environment.
2) In my case the damage seems to come from a little jerk on the cable breaking off the plastic insulator inside the female socket.
3) Rated for 500 insertions ? Preposterous! That is only one insertion of a memory stick per working day for less than two years. Can't say i have ever worn out one of them though, so the reality must be considerably better than 500.
4) Just for curiosity i picked up four USB gadgets at random. Three memory sticks and a USB to Serial adaptor. NONE of them has the USB Logo anywhere on it. One of the memory sticks has a manufacturer's mark on the 'up' side - if it were inserted horizontally. Since writing the original post I have become more sensitive to this orientation issue and have noticed minor things like the split in the case that others have mentioned that provide orientation cues. That was not my major gripe - my major gripe is that flimsy insulator inside the female connector.
Yes, Kim, since your posting, I have become more aware of the orientation of the USB connectors. I never realized, but they are all marked with a symbol of some sort that indicates orientation. How about that.
You're right, KGround, my memory sticks do not have a USB symbol at all. However, following the logic of Apple's connectors, the name of the maker is on the top of my stick for inserting it top up into the horizontal slot on my Mac laptop.
Sorry I got to this discussion so late, and I hope there is someone still following the thread. I teach part-time in a private boys school. Our computer lab regularly has broken USB connectors on the socket portion. It is not unusual to just hsve a hole in the case through which you can see the hardware dangling just out of reach. I will be the first to admit the boys are less than gentle, but I cannot remember ever having a problem with any of the other connectors. I think there is a leverage factor at work here, particularly with flash drives.
All of the posters who have never had a problem, have probably never shared a computer with a group of kids who could break a cannon ball. As far as the markings, I have (2) flash drives, which were purchased very cheaply at a Big Lots, that will fit the socket in either direction. The only way you can be sure they are properly inserted is when the computer recognizes the hardware on the screen.
As a former electrical connector design engineer (including one design USB type B Header), I recognize the design trade-offs. The USB was very cost sensitive and I believe the standard form factor was dictated by a number of companies, but initially was largely driven by DEC in Taiwan around 1995. This was then joined by Compaq, NEC, IBM and others.
Yes, "D-subminiature" connectors are very robust; however, they are somewhat more complex to fabricate, bulkier, and have some issues with pin damage or female contact damage. They also have mechanical limitations with staged engagement as desired for hot-mating.
The "Centronics" style connector was cheaper and robust, but still bulky. Also, with new standards there is often a desire to have a clearly unique form to avoid incorrect plugging of a non-USB device into a USB port. Again, they also have mechanical limitations with staged engagement as desired for hot-mating for the USB application.
The "Circular DIN" connector has some inherent manufacturing challenges that keep the cost higher, and less attractive for a price-sensitive application.
The USB also provided staged engagement between logic and power to permit "hot-mating" with minimal risk to the electronics, and teminals in an eclosed shell to reduce static shock damage to electronics.
I can see how the USB connector is prone to damage from abuse. It is very inexpensive and therefore attractive to OEM designers pressed on the bottom line results. It was designed to have a longer shield engagement to minimize angular loads onto the plastic, but with enough force and leverage sticking out, the stamped shield will bend and allow the plastic to break. It has very diverse operating environments. If broken, it can be replaced, but admittedly only by removing the PCB and replacing the header using a soldering iron. Of course, now there are the USB A, USB B, and at least 2 versions of miniature USB connectors for small applications such as phones and cameras. I am amazed how much abuse these delicate little form factors take and still work.
Design is often a trade-off compromise. Many military and German products are very robust, but meet little market demand due to the price and lower cost competition. Many electronic devices are obsoleted before they die even with these inexpensive constructions.
About the 500 cycle life contraint. This system is to be designed for that life and meeting the required performance. Naturally, the device can be destroyed in one cycle with abuse. If there is no environmental exposure to salt spray, humidity chambers, or other corrosion accelerators, I would expect the gently handled connector to function for 2000 to 5000 cycles (or even more). However, once the gold plating integrity is violated (usually after 250 to 1000 cycles with 15 to 30 microinches of gold), it becomes very sensitive to "flakey" intermittant high resistance connections from oxides. The environment can determine how much oxides are a problem and a mate/unmate cycle can crack through the oxides again for a good connection for awhile.
Thanks for the great discussion form the engineering point of view, David. I never thought about all that went into a "simple" connector. As for me, I have never experienced a great extent of USB problems from the personal / office type usages. My previous employer's machinery is another case, but that is to be expected for the extreme environments they are operating under.
Many, but not all, USB cables or devices have the USB simbol on the top of the connector, so those ones you can count on getting right 100% of the time. A bigger problem for me is that the USB connectors on many PCs are too close together for the plasic plug ends on the cables or thumb drives to be pluged in side by side. That is irritating and inexcusable. I also have a Flip video camera that you cannot plug into the PC with the screen side up, so I can't tell if it is operating or charging. It also exceeds the current available from the USB port on many devices including dedicated USB chargers.
I can't speak to the reliability of the host port connectors (Type A), but I agree that the design ergonomics are poor. My success rate is well under 50% - I rotate the connector 180 degrees multiple times until it feels right, not wanting to force it. While more obvious polarizing would be helpful, why have the polarizing at all? Just make the dang thing work either way you plug it in.
On the device port end (Type B), though, we have experienced poor reliability. The PCB connections break, the connector internals break, but the weakest part of the design appears to be the little plastic center post. Quality varies slightly between manufacturers, but none are very tolerant of a side force. If you are skeptical, try it yourself. Just plug the USB-B connector into a device port and give the cord a sideways jerk. You'll be surprised at how easily the center post breaks, making the connector useless. Imagine picking up a device, such as a USB printer, to move it, but forgetting to unplug the USB. There's your sideways force right there.
We are designing out the USB-B connector in favor of the Mini-B. Our testing and experience have shown it to be a much more reliable connector for us.
I know that the correct way is marked on the connector, but I always forget which way is correct. Also the vertical ports tend to throw me on my laptop. I have seen the same issue with my Flip camera. The screen should face up, but it does not. I am guessing that this was an oversight in design.
Yes, JLS, I have a laptop that has its USB ports too close together to plug in more than one. That's why I started using a hub. I truly can't believe the design. It's a good thing the workaround is easy and inexpensive.
Well, Beth, I think you are lucky. I have seen problems with these connectors. Some just stop working. Others seem to degrade. I get messages that the device can go faster if plugged into a USB 2.0 port (when that has been how it worked all along). I plug it into a different USB port and it works full speed.
I have never had a problem with USB-A, but I have had a USB-B detach from a printed circuit board (part of the microcompuiter in-circuit emultaor) when I was trying to debug a product 500 miles from the office. In order to continue working I had to cut the USB cable and solder it directly to the PCB.
The problem was that there was no mechanical reinforment of the connector which is mechanically held on by the surface mount solder connections only.
USB cables have the USB symbol on the top of the connector. This tells you which side is the top one. And it is easy to then know which way the cable is to be inserted. I double checked all the periherals and cables I have in the lab and all are marked this way.
I have plugged in a huge number of USB cables in using various laptops, testing systems or using development boards. I have never had a cable break. Any failure has been where the cable goes into the housing and this is because the cable is being pulled at a 90 degree angle to connect to where the peripheral or mouse must be.
Surprised at home many are defending the USB design. Yes, there is a little icon on one side that can assist with 'which end up'. But often there is another logo on the other side. So its not always a 'quick look' to tell up from down.
What about when the connection is sideways? Which end is 'up' then? Plus the connection is often on the back of the machine. I often find myself trying in vain to plug the connector in, only to be forced to dig the machine out of its often crammed location, so I can flip it around to see what I'm doing, only then achieving success. It doesn't help that there is nothing to 'guide' the connection into place, as the author mentioned.
I do admit I haven't had trouble with these connectors being damaged. Also, the author mentions the durability of serial 'D' shell type connectors. Mentioning how desk drops that put severe strain on the connector resulted in no damage. that probably has more to do with these connectors 'screw-down' design than the connector itself. That wouldn't be suitable for a connector such as USB that, as the author admits, is designed for frequent connection/disconnection. Not to mention, while I've never damaged a USB connector, I've damaged (and had to repair when others damaged) MANY D shell connectors. Its very easy for one of the pins to become folded over. Sometimes they can be straitened, other times they break, and the cable ruined.
Connector selection is critical to durability and reliability, yet designs chosen to become the standard are often unsuitable for the task. Why is this so difficult to get right?
Good final question, Car Analogy. The comments to the posting may indicate that the USB-A did get it right. When I plug a USB-A into my laptop and I have it the wrong way (because mine is on the side), I'm not likely to break anything. It doesn't take much pressure to find out I don't have it in right.
I have had a number of USB conntectors fail. I have a hub where 3 of the 8 are no longer working. I have not seen as much of a problem on PCs and laptops, but I have seen it. As to the cue to plug it in correctly. When the connetor is vertical (which it is on many PCs) which side is top. When crawling behing a PC to plug in a USB cord the embossed symbol is not visible. Most do not have a contrasting color symbol, they are molded in. I have found that the split in the metal shell is on the bottom. That is more visible than the symbol on the top. The symbol may be obvious to you, but not to the general public. A mechanical visual cue would be better
The fragility is not at the connector itself. Indeed, USB is fairly robust in terms of lifespan (number of plugs/unplugs) for what at first glance is a flimsy, bent metal connector. Where the failure comes in, as it does for most patch cables (my terminology from the old, precomputer days when audio ruled) is where the wire is attached to connector (i.e., the non-business end where the cabling is). Often this is just press-fit, so repeated flexings will cause some of the connections at that end to open. Hence the failure. I believe this is the primary failure of many cables. One outlier is USB3, where you can actually mangle your device, because there's no clear way to tell top from bottom, and it's a tight fit in any case.
I think the author is a bit hard on equipment or using too heavy of a cord to be breaking USB ports. There isn't much to a USB terminal. At first I didn't like the USB design, but it is way better than D-sub terminals. I don't think those things like being plugged in too many times. The pins seems to be the pain culprit and they had to be fastened down to stay pluged. Firewire terminal might have actually been better, but they shot themselves in the foot by not being on flash memory sticks and sticking to the higher end electronics. USB should have had a better indicator of plug orientation. maybe embossed words of "TOP" in the shielding as part of the standard or done what HDMI did and put a step down to a smaller size in the shielding on one side.
I'll add my bit: I've not yet had a failure but I agree it's a flawed design. Without fail I have trouble inserting the connector into the front of my Dell computer, with the computer's connector oriented horizontally, frontally and clearly visible altho not right in front of me. Invariably I have to jiggle it this way & that, whether it's upside down or no, to get it to go in. Unacceptable; altho it must be accepted, of course, since its design must by now be set in stone.
"Set in stone..."? What op-system of yore comes to mind??
I use white typewriter correction fluid ("White Out" with various permutations of spelling) to coat the USB symbol. Some connectors are inverted, but the trick works in most pairings and saves much frustration.
USB has a hot-swap connector and as such, really is a very good design. I asked the folks on the production line if they had any issues. Our equipment has from three to nine USB ports and every one has to be manually plugged into to verify functionality before shipping. They said that they have been using the same test cables or thumb drives for years and don't have any issues with breaking. This testing is done by many different operators.
If you have broken so many, maybe you should slow down when you are plugging them in.
I've seen mashed and broken pins on mini-DIN connectors (PS/2 keyboards and mice) and subminiature D connectors (parallel printers, serial ports and VGA video ports), but I have yet to damage an USB connector. They're rugged and well designed for devices in their price range. Moreover, the network symbol is embossed on one side of the "A" and "B" plugs to make it possible to blind-mate them. That's by design and specified in the USB standard.
If you have a problem with wearing USB receptacles out or breaking them, consider using wireless links instead. One can get printers, keyboards and pointing devices that use Bluetooth, IRDA or Wi-Fi, which can reduce the frequency of mating and unmating cables from the computer's built-in USB port. Also, instead of wearing out the computer's USB port, plug a cheap USB 2.0 hub into the port and wear it out instead. A hub can be obtained for less than $10 these days.
Perhaps the earlier USB connectors were more mechanically rugged, but as they moved toward the commodity status they got cheaper and cheaper, which usually happens as quality is removed.
The reductions in quality don't usually show, such as a cheaper grade of plastic, thinner and softer metal, less elaborate methods of keeping the contacts in place on top of their plastic base, and the whole metal shield not extending into the plastic over-mold portion as far. Exactly the same quality reductions can be found on some HDMI connectors, most of which function as well as the more costly ones. The difference becomes clear when they suffer any abuse at all, and consequently fail. That is when we find that running the outer shell only 0.085" into the plastic overmold does not anchor it vary well. If that same outer shell extended back 0.25" into the overmold the connector would be quite rugged, and it would survive a lot better. That is where the cost reduction engineering shows up, which is when it is exposed as quality reduction engineering.
REally, for ruggedness in dry environments it is hard to beat the 9, 15, and 25 position "D" connectors.
I'm amazed at how many apologists there are for these pitifully-designed connectors ... and I include the HDMI connector in my disdain for the whole class of micro-miniature connectors. I've only experienced one outright failure, but I'm constant annoyed at how difficult it is to align and mate them. All these folks should take a lesson from RJ-45 and similar connectors ... in their smoke-filled backrooms when they conjure up these standards!!
Well, I'm with you Analog Bill. Add to the fragility of the average HDMI cable the fact that most consumers are getting ripped off, paying $25 and up by buying their cables at Radio Shack or Best Buy and/or with their TV. They don't even know that if you go to newegg or one of a host of other online electronics vendors, you can get a cable for the $8 it's really worth. The HDMI cables will actually all fail after a rather small number of cycles (attach/detach). I don't know what order of magnitude, but certainly we're not talking thousands. Worse, I've seen HDMI cables detach by being pulled (not the connector detaching from equipment, but the cable coming off the connector). Compared to HDMI, USB is positively ruggedized.
This is some empty talk. Yes fine the connector is not impervious to damage, we knew that. The reason for most failure would still be the user. I have never broken a USB connector. HDMI is fine too. The issue is not the connector but the clumsiness of the user. As we miniaturize things we have to remove their idiot proof design to remove some of the bulk. Just be a little more careful of how you use the equipment.
How very cavalier of you ervin0072002. I'm guessing you're young, have perfect coordination, smaller-than-average fingers, excellent eyesight, etc. You certainly don't represent all users ... perhaps not even the majority. I compared USB and HDMI connectors to the ubiquitous RJ-45 style because it was so well thought out that you could plug it in even if all you could do is feel your way around in the back of a device in a poorly lit room, without using reading glasses or a flashlight. I simply don't understand the pre-occupation of the industry with ever smaller connectors and ever lossier (signal attenuation) interfaces ... but it's likely because folks like you dictate to the rest of us. Maybe I should think of all this as part of an awkward advance toward fiber interconnects - remember 40 years ago when the industry was telling us that copper would become obsolete in less than 10 years? Well, no, I suppose you wouldn't.
The reason for most failure would still be the user. Little bit of care when the connector is not going in ( rather than forcing it ) will reduce the connector breakage. If you observe (at least in the case of laptops insert the cable when the USB trident logo will be visible from the top.
Analog Bill Here is the reasoning behind the badly designed USB connector "Cost". In engineering team i work with cost and quality are the main considerations. You provide enough quality to meet spec. If the spec is 500 Cycles then ask yourself this did your connectors fail within 500 cycles? Though to be honest i had not fine-combed the spec. If requirement is 500 cycles i am not so psyched about USB all of a sudden. Maybe i have been lucky. I have laptops that have had over 10k cycles on some USB ports and had no breaks. 5-20 times a day and laptop is over 4 years old now not a single USB port went out.
The other failure mode, which hasn't been discussed, but which is relevant, is the connector on the PC side. I had two cases with a Dell netbook (Mini Inspiron, which I think is no longer made) where the female power supply connector on the computer end failed. It was impossible to fix it for several reasons: It was attached to a PC board (I don't remember if it was the mobo or an ancillary board running parallel to the display. Anyway, the problem was that a nipple-like bubble in the metal, inside the connector, which was there to keep the male power supply connector locked in place, had become pushed in, and thus no longer held the power supply connector in place, in less than 500 cycles. (The computer wouldn't get power unless you jiggled the cable just right, but it wouldn't hold in place. I tried to bend the connector metal back out so it would hold the male power supply connector in place, but the female connector was encapsulated in metal bent around it, so no go.
The USB A connectors are supposed to survive for 500+ cycles if the connector purchased for the PC is of the correct quality. I have a laptop from HP where one USB connector failed in less then three months. The only thing I plugged into it wast the HP external DVD drive that came with the laptip. I plugged it in maybe 20 times. The failure was one of the data signal fingers peeled up and was pushed back so could no longer make connection. Was that user abuse or poor quality connector? I could not get HP to repair it under warranty since they claimed it was user abuse. I did find a repair shop to replace the connector for a fraction of their repair cost. The connector has been fine since. I chalked it up to an inferior quality connector. Sad that the manufacturer could not stand behind the product.
The easy fix for this is to buy a cheap and short (or longer) extension cable. If anything wears out, then it is the plug on the cable, which is simple to replace. Maybe that is why I yet have to see any of the USB ports on my PCs fail.
I have several Seagate SATA hard drive connections ( both power and data ) that break off at the root when any sideways pressure is applied. I've had some luck by retrieving the pieces and using a monothithic ( power and data ) cable that gets hot glued on. A $2 cable in quantity on ebay.
That is why I don't recommend a RIGHT ANGLE SATA CABLE. One pull and your 1TB is rendered useless...
Very nice POV from David12345. From my personal experience working in industrial electronic maintenance, supervising and working with a group of technicians, I've never experienced or heard of a USB port failure. I expect that a group of technicians are probably more aware and careful than a group of students or some individuals, but both in our line of work and personal PC use we use USB many times daily. While D-subs have their unique benefits, we have experience failures there the bulk of the connector and cable has caused PCB connection failures. While acknowledging some of the idiosyncrasies noted, such as insertion orientation (even these have not caused damage for us), I have no recommendations for a better connection. For repeated use, USB is better than RJ-45 or any other design in my experience. The approach of "If it doen't fit the first time, flip it" has not caused damage that I expect could result from a brute force, jam it in there approach. It sounds like a little practicle patience is more applicable than redesigning the most convenient and widely adopted port in memory.
From a connector design robustness perspective, I like high density D-sub, the .156" centerline pin and socket connectors, and 0.100" centerline .025" square pin connectors (e.g. - the old Berg Latch-N-Lok) with EMI shield, a rectangular key & keyway polarization, and latching.
The EMI metal-shielded versions of these tend to be more expensive and no standard has been built around these form factors, axcept the VGA Monitors around the 15 pin high density D-sub.
What would stop IEEE from specifyng a 1X4 pin .100" centerline .025" square pin shielded and latching version of USB? This connector is not indestructable, but it could be more robust than the current form, could have staged power engagement with staggered pin lengths and could be with latches or jackscrews.
What would stop electronics designers from then designing in these more robust forms so that connector companies would fall all over themselves to produce them? Yes it may cost slightly more per line at first, but for printers, mice, or laptops that the connectors keep getting pulled-out it could be marketed as a better, more robust product. There are some very cost effective single-beam select gold plated female contact designs out there (e.g. - 3M IDC, Tyco, Hirose, Methode, etc.), all the way to 50 microinch or thicker gold plated military spec box (e.g. - Tyco Box, Berg PV, et.al.) contacts in this form factor. It would be best for the specification to define the plating system compatability such as Nickel/15 microinch minimum Gold plating and mate compatable such as Nickel/Paladium-Nickel/Gold. This is to avoid incompatable mixed mating between gold systems and solder plated systems. Incompatable plating systems can lead to fretting corrosion failure problems.
How about it, can you techy consumers out there support building products with a more robust interface with your purchasing power?
Alternatively an even more robust form factor could be the 1X4 position 0.156" centerline, 0.040" square pin system used in many appliances, but with upgraded gold system contacts and deep-drawn EMI shields (Cheap in high volume, but more robust than having a formed seam) for electronics applications !!!
This could be marketed with a catchy name indicating it it robust such as "Super USB", or "USBrute" interface. The pin assignments and protocol could be identical to the current USB specification for less ambiguity. This could lend itself to an adapters from plain old "USB Type A to USBrute", and USB Type B to USBrute" for back compatability and use of current devices such as jump-drives.
Like Hoffenmeuller, I worked with a bunch of technicians, but at the semiconductor fab I was in, many of them were not as...let's say "diligent". The majority of computers that ran the fab equipment in the RIE process sector had at least one damaged USB port, and one sorry example had both pairs of front and rear ports rendered unusable. This was entirely due to a careless attitude- I even dressed down one tech after I witnessed him "unplugging" a piece of test equipment from about 10 feet away by whipping the cord, and his reaction was as if I was just picking on him- he really did not have a clue!
With proper use and clear access, I have rarely seen a USB port fail, and EVERY one that I HAVE seen fail was through the result of physical damage of some sort. A recent example that comes to mind is a frame mounted computer with a heavy vertically opening hinged door in front of it with no latching mechanism slamming into a protruding thumb drive- proper Engineering controls would not have allowed this to happen.
The damaged USB ports on computers at this fab were clearly the result of physical abuse and carelessness. A contributing factor was the haphazard installation of allot of our "newer" equipment with jury-rigged brackets, no forethought into accessing the equipment for service, and a severe lack of knowledge and discipline in our Equipment Engineering and Maintenance teams. Needless to say, this fab has since went out of business.
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