USB Type A连接器：您需要了解的一切

USB comes in many shapes and sizes, but USB Type-A connectors are the most common type. They’re rectangular in shape and have been in wide use for decades. In the official USB specification, USB-A is known as “Standard-A.”

USB但是有很多形状和尺寸，但是USB Type-A连接器是最常见的类型。 它们是矩形，已经广泛使用了几十年。 在正式的USB规范中，USB-A被称为“ Standard-A”。

A型连接器是什么？ (What Type-A Connectors Are For)

USB Type-A connectors are the most common type of USB connection you’ll find.

USB Type-A连接器是你会发现的最常见的USB连接类型。

You’ll find USB Type-A ports in most modern computers, laptops, game consoles (like the PlayStation, Xbox, and Nintendo Switch), smart TVs, streaming media players, and other devices. These USB Type-A ports are also called receptacles.

大多数现代计算机、笔记本电脑、游戏机(如PlayStation，Xbox和Nintendo Switch)，在流媒体播放器等设备中找到智能电视USB Type-A端口。 这些USB A类型端口又称插座。

Devices like USB flash drives, mice, keyboards, external hard drives, webcams, digital cameras, game controllers, mobile devices, and numerous other peripheral devices and accessories often have USB Type-A connectors (often called plugs), which can be plugged into Type-A ports.

USB闪存驱动器、鼠标、键盘、外硬盘驱动器、网络摄像头、数码相机、游戏控制器、移动设备和许多其他外围设备和附件USB Type-A可插入A型端口的连接器(通常称为插头)。

USB Type-A ports work with all USB versions, from USB 1.1 and USB 1.0 to USB 3.0, USB 3.1, and USB 3.2.

USB Type-A所有端口都可以使用USB版本，从USB 1.1和USB 1.0到USB 3.0，USB 3.1和USB 3.2 。

USB Type-A与向后兼容 (USB Type-A and Backward Compatibility)

When it comes to the Universal Serial Bus (USB) standard, there are two things to think about: Physical connector shape and the underlying protocol (speed.)

谈一般串行总线(USB)物理连接器应考虑两件事：物理连接器的形状和基本协议（速度）。

USB Type-A connectors date back to the the original release of USB 1.0 in 1996, although USB only really became common with USB 1.1 in 1998. However, while Type-A connectors have been around for a while, they still work with the latest modern versions of USB.

USB Type-A连接器可以追溯到1996年USB 1.虽然0的原版USB1998年才真正和谐USB 1.一起使用。但是，虽然Type-A连接器已经存在了一段时间，但它们仍然可以与最新连接USB 1.0一起使用。 USB现代版。

This longtime standard physical connection aids USB in backward compatibility. if you have a modern computer that supports USB 3 and a modern USB device that supports USB 3, you can connect them with a USB cable that supports USB 3 speeds and get all the speed advantages.

这种长期的标准物理连接有助于USB向后兼容。 假如你有支持USB 3现代计算机和支持USB 3的现代USB支持可用于设备USB 3速度的USB连接电缆并获得所有速度优势。

However, if you have a USB 3 device, you can still use that same USB cable to connect it to an old computer that only supports USB 2.0 or USB 1.1. It will work at slower speeds, but that same USB Type-A connector lets you plug your device into almost anything.

但是，如果你有的话USB 3.同一个设备仍然可以使用USB连接电缆只支持USB 2.0或USB 1.旧计算机1。 它会以相同的速度以较慢的速度运行USB Type-A几乎任何设备都可以插入连接器。

In other words, you can plug any USB Type-A plug into any USB Type-A port and it will “just work.” If the devices are different generations—if you plug a 20-year-old USB drive into a modern PC, for example—they may perform slower, but they will work.

换句话说，你可以做任何事情USB Type-A插入任何插头USB Type-A端口，它将正常工作。 如果设备的版本不同(例如，如果您将使用20年USB现代插入驱动器PC它们的性能可能会变慢，但它们会起作用。

蓝色USB连接器通常更快 (Blue USB Connectors Are Often Faster)

USB Type-A connectors and ports that support faster USB 3.0 speeds often (but not always) have blue on the inside. Type-A connectors that only support slower USB 2.0 or USB 1.1 speeds often (but not always) have black on the inside.

支持更快的USB 3.速度的 USB Type-A连接器和端口的内部经常(但并非总是)带有蓝色。 仅支持较慢的USB 2.0或USB 1.1速度的A型连接器的内部经常呈黑色，但并非总是如此。

The same goes for ports: USB 3.0 ports often have blue on the inside and USB 2.0 ports often have black on the inside. However, this isn’t guaranteed.

端口也是如此：USB 3.0端口的内部通常为蓝色，USB 2.0端口的内部通常为黑色。 但是，这不能保证。

Type-A connectors that support USB 3.0 speeds—the ones that often have blue on the inside—have nine pins versus the four pins found in older USB connectors. However, they’re still backward compatible and those faster speeds will only work when two USB 3.0 devices are connected to each other. Otherwise, they’ll use the slower speeds.

支持USB 3.0速度的Type-A连接器(内部通常带有蓝色)具有9个引脚，而较老的USB连接器只有4个引脚。 但是，它们仍然向后兼容，只有两个USB 3.0设备相互连接时，这些更快的速度才有效。 否则，他们将使用较慢的速度。

USB Type-C是未来 (USB Type-C is the Future)

While USB Type-A is still the connector in most widespread use, it isn’t the future. The future belongs to USB Type-C, which is already common on new devices.

尽管USB Type-A仍然是最广泛使用的连接器，但这不是未来。 未来将属于USB Type-C ，它已在新设备上普遍使用。

Some modern devices even have both USB Type-A and USB Type-C ports so they’re compatible with everything. A few even abandon USB Type-A and only have USB Type-C ports.

一些现代设备甚至同时具有USB Type-A和USB Type-C端口，因此它们与所有设备兼容。 一些甚至放弃了USB Type-A，而只有USB Type-C端口。

You can always use a “dongle” that functions as an adapter. For example, a USB-A device could be connected to a Type-A-to-Type-C dongle, letting you plug it into a USB-C port. This works because, underneath the physical connection difference, USB is still compatible.

您始终可以使用充当适配器的“加密狗”。 例如，可以将USB-A设备连接到Type-A到Type-C加密狗，让您将其插入USB-C端口。 之所以可行，是因为在物理连接差异下，USB仍然兼容。

USB-C cables are smaller and eliminate the need for mini USB ports and the Micro-B connectors. These are other smaller USB connectors that were used to connect USB Type-A devices (like laptops and chargers) with smaller devices (like smartphones) that had no room for a full USB Type-A receptacle. With USB-C, there will just be one standard USB Type-C port for all devices. Once it’s widespread, you won’t need different types of USB cables for different devices.

USB-C电缆更小，不需要迷你USB端口和Micro-B连接器。 这些是其他较小的USB连接器，用于将USB Type-A设备(如笔记本电脑和充电器)与较小的设备(如智能手机)连接，这些设备没有空间容纳完整的USB Type-A插座。 使用USB-C，所有设备只有一个标准USB Type-C端口。 一旦广泛使用，您就无需为不同的设备使用不同类型的USB电缆。

USB Type-A将被USB4淘汰 (USB Type-A Will Be Sidelined By USB4)

The smaller USB Type-C connector will actually be required by the next USB standard, USB4.

下一个USB标准USB4实际上将需要较小的USB Type-C连接器。

But, while the connector shape changes, the underlying USB standard is still backward compatible with devices from previous USB standards.

但是，尽管连接器形状发生变化，但基本的USB标准仍旧与以前的USB标准中的设备向后兼容。

You’ll still be able to plug an older USB Type-A device into a future USB4 device that only has Type-C receptacles. You’ll just need a dongle that will convert the physical USB Type-A connection into a USB Type-C one.

您仍然可以将较旧的USB Type-A设备插入将来仅具有Type-C插座的USB4设备。 您只需要一个加密狗，即可将物理USB Type-A连接转换为USB Type-C连接。

翻译自: https://www.howtogeek.com/690160/usb-type-a-connector-everything-you-need-to-know/