difference between usb 2.0 and 3.0

What is the difference between usb 2.0 and 3.0?

What is the difference between usb 2.0 and 3.0? - Table of contents:

The USB standard was released in the year of 1996, currently maintained by the USB Implementers Forum. There have been three generations of USB specifications: USB 1.0, USB 2.0, and USB 3.0. And USB 2.0 and USB 3.0 are commonly used on various electric devices. Following mainly describes the difference between usb 2.0 and 3.0.

difference between usb 2.0 and 3.0

USB is brief for Universal Serial Bus, which is an industry standard that establishes specifications for cables and connectors for connection and power supply between computers, peripheral devices, and other storage devices.

What Is USB 2.0

On April 27, 2000, the USB-IF organization proposed the USB2.0 bus protocol specification. The protocol has a high-speed transmission rate of 480Mbit/s, is backward compatible with low-speed 1.5Mbit/s and full-speed 12Mit/s, and provides a power supply voltage of 5V and a maximum current of 500mA; the maximum transmission cable is 5m; through HUB cascading, A USB interface can theoretically expand 127 USB devices; it supports 4 transmission methods: control transfer, interrupts transfer, isochronous transfer and block transfer.

Nowadays, USB 2.0 is being replaced by 3.0 in many high-end motherboards.

difference between usb 2.0 and 3.0

What Is USB 3.0

USB 3.0 was released in November 2008, which is the third major version of the Universal Serial Bus standard for interfacing stretched bar lcd monitor and electronic devices. USB 3.0 has gradually become the new standard for USB devices by providing a lot of improvements over USB 2.0.

The major one is the data transfer rate. The data transfer rate of USB 3.0 is up to 5 Gbit/s, which is about 10 times faster than the USB 2.0 standard.

These types of USBs are distinguishable by their blue-colored inserts and are usually equipped with a 3.0 logo.

difference between usb 2.0 and 3.0

There are several differences between USB 3.0 and USB 2.0:

1. Physical Port

You may wonder: does USB 2.0 and USB 3.0 look the same? Is there any physical difference between them? How to distinguish USB 2.0 and USB 3.0 from their physical characteristics?

Actually, it is not difficult to tell their physical difference. The USB 2.0 Connectors is colored white or black inside, while the USB 3.0 is colored blue inside.

So if you want to find out whether the USB port on your computer or USB flash drive is 2.0 or 3.0, you can distinguish them by the USB port color inside.

Another physical difference between USB 2.0 and USB 3.0 is the number of wire connections.

USB 2.0 has a total of 4 connector wires, supporting half-duplex communication. As for USB 3.0, it has a total of 9 connector wires. With these five additional wires, it increases the bandwidth of USB 3.0 by permitting two-way communications simultaneously.

difference between usb 2.0 and 3.0

2. Speed

Compared with USB 3.0 speed, USB 2.0 speed is extremely slow, which is at 480 megabits/s (60MB/s). Although it is a bit slow for data transfer, for connecting peripherals such as keyboards, mice, headsets, and similar, the speed is sufficient.

As for USB 3.0, it is approximately 10 times faster than USB 2.0 with a data transfer rate of up to 5 Gbit/s (625MB/S).

However, that’s just a theoretical number that points out the maximum data transfer rate through a USB port. Well, in reality, the transfer speed of USB 2.0 and USB 3.0 depends on the specific drive. For example, USB drives will be limited by the speed of their flash memory.

3. Power Management

Compared with USB 2.0, USB 3.0 also provides more efficient power management and increases power delivery.

USB 2.0 provides power up to 500 mA whereas USB 3.0 caters to up to 900 mA, resulting in an increase in total power delivery from 2.5 W to 4.5 W (at 5 V). So as for USB 3.0 vs 2.0 charging, USB 3.0 devices can be charged faster, and USB 3.0 ports can support more power-consuming devices.

The USB 3.0 devices contribute more power when required and conserve power when the device is connected but idle. So as for power management and power consumption, USB 3.0 is more advanced than USB 3.0.

difference between usb 2.0 and 3.0

4. Compatibility

USB 3.0 ports are backward compatible. For example, if you connect a USB 2.0 drive or earlier versions to a USB 3.0 port, the drive will work as normal.

USB 3.0 devices are also backward compatible. That is to say, if you plug a USB 3.0 flash drive into a USB 2.0 port on your PC, it still can be read. However, the US 3.0 will work at the speed of the port, in which case the super-fast transfer rate of USB 3.0 is not fully realized.

difference between usb 2.0 and 3.0
USB 2.0 USB 3.0
1 The data transmission rate of USB 2.0 is 480 Mbps. While the data transmission rate of USB 3.0 is 4800 Mbps.
2 USB 2.0 has four wires. While USB 3.0 has nine wires.
3 USB 2.0 is one-way communication. While USB 3.0 is a two-way communication.
4 USB 2.0 is less costly. While It is costlier than USB 2.0.
5 USB 2.0 cable length can be up to five meters. While USB 3.0 cable length can be up to three meters.
6 USB 2.0 delivers 500 mA amount of power. While it delivers 900 mA amount of power.
7 A black block occurs within USB 2.0. Whereas blue block occurs within USB 3.0.

Unmarked pictures come from Internet, and source: … …

A USB 2.0 can be used in a USB 3.0 port. For example, if you connect a USB 2.0 device to a USB 3.0 port, the device will work as normal. But the transfer rate will fall back to the speed of USB 2.0, so you won’t get a high transfer speed.
You can identify a USB 3.0 port by checking its physical port. A USB 3.0 port is distinguishable by its blue-colored insert and it is usually equipped with a 3.0 logo. You can also open Windows Device Manager. Expand Universal Serial Bus Controllers and check if there is an item that has USB 3.0 in the title. If YES, it means you have a USB 3.0 port on the PC.