By PURPLELEC | 16 November 2023 | 0 Comments
The difference between USB2.0 and USB3.0
What is USB2.0
The USB-IF organization proposed the USB2.0 bus protocol specification on April 27, 2000. This protocol has a high-speed transmission rate of 480Mbit/s and is backward compatible with low-speed 1.5Mbit/s and full-speed 12Mit/s. The external power supply voltage is 5V and the maximum current is 500mA; the maximum transmission cable distance is 5m; through HUB cascading , a USB interface can theoretically be expanded to 127 USB devices; it supports 4 transmission methods at the same time: control transmission, interrupt transmission, synchronous transmission and batch transmission.
What is USB3.0
The USB-IF organization launched the SuperSpeed USB 3.0 specification on November 17, 2008. Compared with USB2.0, USB3.0 provides a higher ultra-high-speed transmission speed of 5.0Gbit/s and is backward compatible with the transmission rate of USB2.0; the external power supply voltage is still 5V, but the maximum current reaches 900mA; And a new power management function has been added to support standby, sleep and temporary modes, which saves more power; and full-duplex communication has been introduced.
The difference between USB2.0 and USB3.0
1. Interface color
In order to distinguish USB3.0 and USB2.0 more intuitively, the standard specification stipulates the color of the interface. The color of the middle plastic piece located at the USB interface is different. The color of USB3.0 is blue. The color of USB2.0 is black or white.
2. The number of pin interfaces is different
Judging from the pins of the USB socket, USB2.0 adopts a 4-pin design, while USB3.0 adopts a 9-pin design. In comparison, USB3.0 is more powerful.
3. Different transmission rates
The USB3.0 transfer rate is approximately 320MB/S, and the theoretical upper limit is 640MB/S.
The USB2.0 transfer rate is 30MB/S, and the theoretical upper limit is 60MB/S.
From the perspective of transmission rate, the transmission speed of USB 3.0 is 10 times that of USB 2.0.
4. Different power consumption
The power supply capacity of USB3.0 is 1A, which means the power consumption is 5W, while the power supply capacity of USB2.0 is 0.5A and the power is 2.5W. Therefore, users who need to use the USB port to charge their mobile phones are best to choose blue USB3.0 because its output power is higher!
5. Different working modes
Since USB3.0 can realize bidirectional data transmission, its working mode is full-duplex mode. USB2.0 is in half-duplex mode.
Leave a Reply
Your email address will not be published.Required fields are marked. *