I’ve been trying to understand the compatibility differences between USB 2 & USB 3, specifically for charging & less about data transfer
The original question I researched myself was whether there is a requirement for all elements in the charging system (the power port, the cable, and the receptacle port) to have USB 3 compatibility. And it does appear that for USB 3 power rates to work, all 3 elements must all be USB 3.
Initially I was worried that as I got new devices I haven’t kept track of what cable goes with what port or device, so maybe I was lengthening charging times by mixing up components.
As it turns out, my initial question was moot. To my surprise, it appears that everything I have is still USB 2, including my month old new model Canon inkjet. According to the what I’ve found online USB 3 is differentiated by a blue insert in the USB instead of white or black.
Seeing this was introduced in 2008 as the “new standard”, why hasn’t it been adopted more widely? It seems like there has been plenty of time to catch on. There’s obviously more to this story, can anyone shed some light on this?
Lots of IMHO here - but for many things, especially input devices, you just don’t need high speeds. That printer will only print so fast, no matter how fast it receives its data. Mice and keyboards it would make little to no difference as well.
Where USB 3.0 and 3.1 come in handy is in external drives - that makes a noticeable difference when you’re transferring gigs of data to an external hard drive or USB stick.
I don’t pretend this is a complete answer to your question, but first of all the type A plugs and ports are compatible, but a regular version 2 port only supplies up to 500 mA, while a version 3 allows 900 mA. For higher currents you should check that your port is a charging port which supports it. For high power delivery (like 100 W) the power supply and device and cable all need to support the newer power delivery standard.
In my experience these are hardly rare. Did you carefully check the labels on your ports to positively identify them, not just the color?
But, practically speaking, if a given plug fits into a given port then yes, they are compatible and you can let the devices work their magic.
In fact, what prompted my question was flash drives - my son needed a new one for school and I bought a USB 3 since I assumed it would be faster. I incorrectly assumed that my 2 year old computer would have USB 3. That got me to wondering how the USB systems worked and about whether new devices (which I erroneously assumed were all USB 3) would work if I mixed my components up.
Contrary to what DPRK is saying, everything I read says that although they are compatible physically, but the USB system only works as fast as the slowest component. Plugging a USB 3 cable and a USB 3 device into a USB 2 port (on a computer or wall charger) will only transfer data or charge at a USB 2 rate.
My 2 year old computer only has USB 2, so even with the USB 3 memory stick, it won’t transfer data faster. As far as peripherals and my phone chargers etc go, nothing seems to be USB 3. There are no markings or blue sections which seem to be the indicator.
I think the case is correct for things like mice, keyboards not to need USB 3, but I still don’t get it for things that require charging or data transfer. It also seems to me that charging my phone with USB 3 in 1/2 the time would be a great benefit.
This standard was developed 9 years ago and still not widely implemented, so obviously it’s dead on arrival. Still the same question: what gives?
Don’t know about the charging. But yes, the blue means 3.0, but not all 3.0 are blue. Sometimes the receptacle is the same color as 2.0, but instead has a “SS” logo near it.
But as far as charging goes, you should have an AC adapter with USB ports, and not charge from a computer most of the time. Most adapters draw much higher amperage than the standards (e.g. 3000+ mA), and if the device doesn’t go that high then it will draw as much as it can; you won’t “burn out” your device.
Not sure why it’s not universal now. For example, Dells at work have 4 ports on the front, only one of which are clearly marked SS.
Double check on your 2 year old computer. It really should have some USB 3 ports. Check your manual as to which ones they are. (A quick Google on the specific model number should at least tell you that it has them.)
Note that the additional hardware needed for USB 3 costs device makers money. The I/O channels and power requirements have to be added for each set of ports. (Sharing an internal bus among too many devices hurts the speed.) So they might give you just two.
It’s hardly a dead tech. I’ve recently acquired some cheap little devices that I’ve installed full Linux distros on each of which has USB 3.0 and SATA ports. (Sadly, the Raspberry Pi hasn’t joined the USB 3 universe yet.)
As thelurkinghorror alluded, the 500 mA number for USB 2 is a minimum. The port has to provide 500 mA to meet the standard. Nothing in the standard prevents it from providing more amperage. Many computers, and most wall wart chargers, provide more. So you don’t need USB 3 to charge faster.
But 500 mA is a maximum for the device to draw. USB devices are not allowed to draw more than 500 mA, unless it can identify the USB port as being capable of higher current. So if a USB port is capable of supplying 1A, but your phone doesn’t identify it as a 1A port, it will only charge at 500 mA.
Unfortunately there are different standards for identifying high-current ports. Apple first implemented this idea for the iPad, then Android device manufacturers chose to (or were forced to) use a different standard. Then there’s Qualcom Quick Charge which is yet another standard. Thankfully there are now “smart” chargers that can talk to all these different devices and convince any of them they are connected to a high-current port.
At least it was all good until USB-C, because Qualcomm came up with Quick Charge 3.0 before an official USB Power Delivery standard for USB-C was established. And in the meantime some companies came up with “cheater” cables that fool the device into thinking it’s connected to a high-current port even if it isn’t. So if you use a cheater cable to connect to a low-current port, it could draw too much current and burn out the fuse or damage the port. So be sure to read the reviews before buying any USB-C to USB-C cable if you’re going to use it for charging.
To be frank, it’s a complete shitshow. The TLDR is to only use manufacturer approved (or reviewer validated) charging devices: the charger AND cable. It’s the only way to really be sure.
In the USB 2 era, there were a variety of quick charging standards, of which Qualcomm QuickCharge is just one (and even that has several “generations”). They all function similarly, delivering 5V power with higher current, from 0.5 to 3A.
In the USB 3 generation, the old standards still work, but only if the charger supports the higher amperage. Most computer ports do NOT. Even the SS ones only promise higher data speeds, not charging. Some manufacturers will have 1.5 or 2A ports, but those aren’t always enough to quick charge devices that want 3A. The higher powered ports may or may not be the same as the SuperSpeed (SS) ports.
To make matters even more confusing, the USB people also developed a new connector/cable type, Type C, in addition to USB 3. Not all USB 3 cables use Type C. But Type C allows even HIGHER power, up to 100W theoretically, by upping the voltage AND the amperage using a new standard called USB Power Delivery, completely separate from Qualcomm’s Quickcharge and competing USB 2.0 era technologies (here’s one writeup). This requires special equipment at all ends (charger, cable, device) but there’s no clear labeling to indicate when something has this. It’s a complete and utter mess. People hate on Apple for their certified, expensive connectors… but without them, in a freer marketplace, you get this exact situation where 90% of the stuff out there is crap and unable to do what your manufacturer wants it to. Buyer beware.
I know that no amount of anecdotes can become real data, but the company my daughter works for had a problem with their mice, keyboards, and docking stations. The company had replaced all their laptops for their remote workers just a few months ago, and that’s when the complaints started about their keyboards and mice having latency issues.
Stuff like, “Press a key, wait a second or two, key appears on screen”. Or, “Move the mouse and watch it finally catch up on the screen.”
The IT department kept saying it was probably due to the security features of the VPN software they had to go through.
Turns out that their mice and keyboards were plugged into a USB docking station/screen extender device. The device was plugged into a USB 3.0 port, but somehow, it couldn’t handle the slower communications from the USB 2.0 devices.
Finally, IT told everyone to plug the docking station into the other port and everything worked fine.