Attività

What does “USB” stand for?
The acronym “USB” is short for the term Universal Serial Bus, a hardware interface that was developed so that peripheral devices like computer mice, keyboards, printers, digital cameras, scanners, PDA’s and MP3 players can be easily connected to PCs. Computer manufacturers first began to replace serial and parallel ports with USB ports in 1997; today, every PC on the market contains at least 4 ports for USB connections.

What are typical transmission speeds for USB cables?

Generally speaking, USB cables are classified into one of two different bandwidth groups: 1.1, which transfers data at a maximum rate of 1.5 Mbit per second, and 2.0, with a 480 Mbit per second data transfer rate. USB 2.0 is backward compatible with the lower data transmission requirements of 1.1, but the substitution can’t be reversed; 1.1 just can’t deliver the rate of data transfer that USB 2.0-rated devices need.

In addition to the bandwidth classifications listed above, USB devices can also be labeled in the following “speed” categories, which specify the amount of bandwidth they need to operate:

Low Speed: The “ low speed” rating indicates that a device requires minimal bandwidth (1.5 Mbit/s) to function, so it can be used in conjunction with either 1.1 or 2.0 USB cables. Joysticks, keyboards and computer mice are a few common examples of low speed devices.

Full Speed: Devices labeled “full speed” need a signal rate of 12 Mbit per second. Since this is such a common bandwidth requirement, all USB hubs on the market have been designed to support Full Speed. And even though the data transfer speed is higher, Full Speed – like Low Speed – transmits equally well via 1.1 or 2.0 USB cables.

High Speed: “ High speed” USB devices run at 480 Mbit per second, and require a 2.0-rated USB cable.

What does it mean when USB cables and devices are described as “hot swappable?”

One of the most convenient features of USB C PD cable and devices is their ability to be “hot swapped,” which means that they can be plugged into – and unplugged from – a computer as needed, without that computer needing to be powered down first.

Is there an organization that sets USB performance standards?

The USB Implementers Forum, a non-profit organization otherwise known as the USB-IF, is the group responsible for promoting and supporting USB standards. Made up of companies that developed USB technology, the USB-IF includes notable corporations like Agere Systems, Apple Computer, Hewlett-Packard, Intel, Microsoft, and NEC. Within the USB-IF are four working committees: the Compliance Committee, the Device Working Group, The Marketing Committee, and the On-The-Go Working Group.

How many types of USB connectors are there?

USB connectors – and, by extension, USB ports – can be found in two different styles: type “A” (for hosts and USB hubs) and type “B” (for peripheral devices). In addition, USB plugs fall into three different size ranges: standard, mini, and micro. Here’s a general breakdown of how connector styles differ by size class, and the applications each is used for:

Standard USB: Standard is the original USB connector size, and the largest of the bunch. Standard-size “A” connectors have a long and extremely narrow rectangular shape (approximately 4mm x 12mm), while standard “B” connectors are still oblong, but with shorter and wider proportions (at roughly 7mm x 8mm, they’re closer to being square). Standard USB connectors are typically used with, well, “standard” peripheral devices like printers, keyboards, computer mice and scanners.

Mini USB: Developed for use with small, portable peripherals like digital cameras, cell phones, PDA’s and MP3 players, Mini USB connectors feature a more compact and space-efficient design than standard USB connectors. Unlike standard A and B connectors, Mini A and B have very similar shapes; however, it’s possible to distinguish one from the other by the upper halves of their vertical edges: Mini A’s sides are straight, but Mini B’s are rounded.

Micro USB: In January 2007, the USB-IF approved the most space-conscious connector size to date: Micro USB. Micro USB connectors are approximately 50-60% smaller than mini connectors, and replace Mini USB in many new PDA’s and Smartphones.

Neckband Headphones: Why Is This Design Becoming So Popular?
At some point during the past few years, you’ve no doubt noticed an intriguing new phenomenon. More and more people are sporting what can only be described as high-tech collars with headphones sprouting out the sides. Call them what you will—”neckband headphones,” “behind-the-neck headphones,” or even the more obvious “collar headphones”—but this distinctive modern style of in-ear and around-the-neck earphones is all the rage as of late. And if you haven’t experienced them yourself, you may be wondering what all the fuss is about.

Ultimately, the success of neckband headphones boils down to three essential considerations: a unique combination of convenience, features and battery life unmatched by any other in-ear headphone design.

Your Headphones Are Right There Where You Need Them, When You Want Them

The first major benefit of neckband headphones is perhaps the most obvious, but it’s worth pointing out. Given that the earbuds are hanging around your neck, mere inches from your ears, means you won’t have to dig through your bag or your pockets when you want to listen to some tunes or take a phone call. And since virtually all neckband headphones connect to your smartphone or personal media player via Bluetooth, those two tiny little cords connecting the collar to the earphones are the only cables you need to worry about. That means no more rat’s nests to untangle. Since those cables aren’t extending from your head to your pocket, it also means fewer opportunities to snag them on a doorknob and rip your earphones out of your ears. Or worse yet, break the wires, rendering your precious audio purchase worthless.

That Neckband Headphones Are Full Of Surprises

While we all appreciate the lightweight and convenience of in-ear headphones, as well as the add-on features commonly found in many popular models these days, those two desires can conflict with one other. After all, the more electronics you pack into one of those little housings, the bulkier, heavier and more cumbersome it gets. That’s the definition of defeating the purpose.

Housing all their electronics inside the neckband headphones allows for additional features, without dragging down your ears or increasing discomfort. These features include:

Active noise cancellation: It’s a feature we all love, but there’s a good reason it’s more commonly found in full-sized, over-ear headphones. Good noise cancellation requires sophisticated electronics, and those electronics must go somewhere. That’s why most in-ears with active noise cancelling capabilities either come with a gigantic in-line control box, or bulge way out of your ears. Moving that circuitry to inside the neckband headphones means the bits you stick in your ears can stay compact and light, without any sacrifices in terms of the quality of noise cancellation.

What’s more, the neckband headphones allows for a combination of features you rarely ever see in in-ear headphones otherwise: active noise cancellation and Bluetooth wireless connectivity.

More convenient controls: Granted, in-line controls have been a feature of headphones since smartphones have existed. But have you ever found yourself fumbling your way down your headphone cables in search of the controls, only to forget which button does what? With neckband headphones, that’s generally not a problem. With the controls right around your neck and easy to reach, you’ll likely find yourself using them to pause, play, fast-forward and accept calls.

Enhanced telephony: If you regularly rely on a Bluetooth wireless connection, you’ve no doubt experienced this at some point—you’re taking a break from listening to your tunes or podcasts, but didn’t bother to unpair your headphones or turn them off. An important phone call comes through, and you miss it.

What Charger Can I Use?
As long as you’re using the right cable or the right wireless standard (and it’s difficult not to), you can use just about any wall charger with your phone. Modern-day handsets will regulate the power draw to keep the battery protected, so there’s no danger of blowing up your phone by using a charger that’s too powerful for it.

That said, be wary of using cheap, no-brand chargers, or chargers that have been sitting around for years, as they may not necessarily stick to the same safety standards as the rest. We’re not saying all of these chargers are dodgy, but to be safe it’s always worth going with a newer charger from a reputable manufacturer or accessories maker, even if it’s a little bit more expensive.

The bottom line is that while just about any new-ish charger will work with just about any new-ish phone at this point, you won’t necessarily see the maximum charging speeds or the most efficient charging rate if you’re not using kit made by the same company.

As we alluded to above, this is particularly true when it comes to fast charging, as phone makers like to deploy their own standards and methods—for the maximum fast charging rates, you’ll usually need to plug in the charger specifically made for your phone. Use other chargers if you need to, but the official charger when you can.
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