Because different types of USB cable have different maximum lengths. The first version we really need to worry about is USB 2. USB has a maximum data transfer rate of Mbps, which was blazing fast for the time. It was good enough for transferring some documents or songs, but not for video. As more people started storing larger files, a faster standard was needed. The answer to this need was USB 3. USB 3. It also offers upgraded power, supplying 15 watts instead of 7. This allows it to be used for a wider variety of devices.
For instance, older USB 2. Newer, USB 3. Released in , USB 3. It offers the same 15 watts of power, but doubles the data transfer rate to 10Gbps.
This was done, in part, to keep up with Apple Thunderbolt capabilities. Finally, the faster read-write speeds helps you get the most out of an external SSD. However, only USB 3. On a PC or Mac, you can find out what type of port you have through the system menu. Right out of the box, a USB 2. This is just fine, but keep in mind that this 5-meter limit is still in effect. In other words, you can connect a 6-foot cable to a foot cable, and everything will be fine.
The overall length of the cable is 16 feet. The overall length will be 20 feet, which is too long for USB 2. The longer you extend the cable, the lower the speed and the less power it will provide. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams?
Learn more. Maximum length of a USB Cable? Ask Question. Asked 12 years ago. Active 9 months ago. Viewed k times. What is the maximum length of a USB cable? What is the maximum length achievable when using USB extension cables? Improve this question. Gaff Click Ok Click Ok 3, 9 9 gold badges 41 41 silver badges 43 43 bronze badges. As an alternative, there's a 10m wireless USB option.
Add a comment. Active Oldest Votes. Improve this answer. WAF 5 5 bronze badges. Just FYI, it's not really a timing issue, since using hubs doesn't mitigate the signal's propagation time. If the cable was too long, the digital logic levels might not be triggered properly at the receiving end. Each hub "resends" the signal so-to-speak, which is why this solution works. Breakthrough No, the signal voltage is easy enough to amplify; I think it is about the timing on the single link.
The problems from capacitance and inductance are - if you look closely - exactly the timing issue; The signal is spread in time direction. But even the latency can be relevant inside the link protocol; It get's much easier if you can use a full round trip for each byte you transfer - no need to keep track what may need repeating on a glitch.
And the latency over five hubs is just the same for the device to computer link ; — Volker Siegel. Those 5 hubs connected in series, do they need to have an external power supply? If you know the hubs power consumption and the end devices power need, you can calculate whether your mA from the source will be enough. Over longer stretches the village drop might be enough to need at least some posted hubs in the sequence. What is a "low speed device" and how do i check if my one belongs into those?
Show 1 more comment. There are three factors: Physical signal integrity over a twisted-pair differential for a realistically manufacturable cables impedance matching, cable uniformity, signal loss. A USB device is allowed to respond in bit times, which is ns. How did you check the error rate on your setup? Ali Chen, thanks for this incredibly informative information post! ZAB The experiment was done between two highly polished USBB hubs, with all care about traces and connectors and termination self tuning.
There were no protocol errors, at all. Range is up to ten metres, but in practice wireless USB is mainly used at close range. Wireless USB has never really come to the fore because Bluetooth is so popular. All of the methods described are very effective. However, in most cases placing extension cables over greater distances is usually a last resort. Because most people nowadays want to avoid additional cables and are more likely to look for solutions for connecting devices to a network via WiFi.
However, there may be situations in which an extension cable is the fastest and most cost-effective solution. Your email address will not be published. Save my name, email, and website in this browser for the next time I comment. Search the Magazine Search the shop. Toggle navigation. This is how a USB connection can work over longer distances If you connect several conventional USB cables to one another, you will notice that the signal will be lost.
Or you can connect the USB connection to other transmission standards. Avoiding cable clutter All of the methods described are very effective.
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