USB Type-C port, also known as USB-C, is a universal serial bus (USB) hardware interface form. The biggest feature of its appearance is that its upper and lower ends are exactly the same. Compared with Micro-USB, it means that users do not have to distinguish USB from the front side, and the two directions can be inserted.
In recent years, as the size of electronic products is thinner, the data interface we use is a little "thinner". Many of the old interfaces are eliminated because of the unusable thickness of electronic products.
Now we see many interfaces, basically all have smaller and smaller versions, for example, HDMI has mini-HDMI and microHDMI, USB also has mini-USB and micro-USB.
These smaller versions can just be used in light and thin products. However, for USB, micro-USB is not perfect.
The micro-USB shown in the figure above is actually a portable version of USB 2. As the bandwidth of the USB version increases, the new USB3.0 is not compatible with the former micro-USB form, and it has been improved.
Although the thickness is the same as micro USB 2, it has become a lot longer. For this kind of "portable" interface, the increase in length will undoubtedly affect the use, and very unpleasing. Why do you have to design this?
Because it wants compatibility.
Carefully observed, this micro-USB 3 is actually made up of two segments, and the longer part is actually exactly the same as the micro-USB 2. That is to say, this interface is made in order to be compatible with micro-USB 2.
But this is understandable. The biggest feature of USB is compatibility. After many years of revision, old devices can still be used. Strong compatibility makes USB an irreplaceable existence in electronic products.
Unfortunately, this interface guarantees compatibility, but it loses its original meaning. The existing electronic products, in addition to the mobile hard disk box, almost can not see its existence, in addition to Samsung note3, flat and mobile phones can hardly see its existence. The choice of the market proves that the design of micro-USB 3 is a failure.
USB has been inseparable from human, and can't always use micro-USB 2? Now a new version of USB is urgently needed. While maintaining the size of the micro-USB 2, it can also have higher bandwidth to transmit data.
So, USB Type-C appeared.
When you talk about the form, the mini-USB and micro-USB are just the same, but these two are relative to the standard USB. And the standard USB, in fact, is called USB Type-A.
This graph roughly explains different forms of USB. It can be seen that these interfaces correspond to different versions (2.0/3.0). Basically, USB 3 era is compatible with USB 2.
Type-A's USB 3 and 2 are of the same shape, and the device can also be compatible with each other, while Type-B is different. The 2 version of Type-B's wiring can be inserted into the 3 version interface, but vice versa.
Referring to the connection and interface, it is also necessary to find out what is the male port and the female port.
When the device is connected to a computer, the interface on the general computer is called the female port, and the interface of the connection line is called the male port.
As you just said, the Type-B's female port has a downward compatibility, but the male port can't be down - compatible. This is the decrease in compatibility caused by the new version of USB, and now only Type-A can be compatible.
In this situation, USB has to think about a new form, and that's what Type-C does.
USB Type-C is brought together with the USB 3.1 standard, and because it is a new form, TypeC does not actually have the problem of "compatible" old devices.
The word "version" has been mentioned in the previous interpretation. In fact, some places are prone to cause ambiguity. Versions such as Type-A and Type-C, called USB interface forms, and 2, 3, called USB interface specifications.
For example, a garment, its appearance is analogous to the former, and the size and material are analogous to the latter. The former makes USB can be applied to a variety of equipment, to develop equipment according to the shape features, such as Type-B is common in the printer, personal speculation this interface stability is higher, the transmission of data is to ensure the stability of the latter is USB; the organization to adapt to the development of the times to enhance the function of USB. The most intuitive promotion is that each generation of USB can improve a lot of bandwidth, USB2.0 theory bandwidth 480Mbps, and USB3.0 is 5Gbps, a lot of times.
To introduce the features and features of USB Type-C, you have to talk about what is added to the USB 3.1 specification.
USB 3.1 is divided into two kinds of Gen 1/Gen 2, and USB 3.1 Gen1 is the rename of USB 3, that is to say, there is no change at all. All without reference to the Gen 1/Gen 2 distinction on the market generally refers to the USB 3.1 Gen2.
The propaganda of USB 3.1 is very confusing in the market. Most manufacturers still use "USB 3" in copywriting, but do not distinguish Gen 1/Gen 2. The evaluation room has to use USB 3 to consider the acceptance of Xiao Bai. In this bad situation, the pot has to be dumped to the USB organization.
The original release of the USB 3.1 specification, and no mention of Gen 1/Gen 2 to distinguish, even issued Type-C interface when there is no distinction, then suddenly changed the results, USB 3 in USB 3.1 forced the family, then in order to distinguish between "real" USB 3.1 Gen 1/Gen 2 introduction......
So most manufacturers and media estimates are used to the previous statement, without timely correction, little white is more indistinguishable.
The bandwidth of USB 3.1 Gen 2 is 10Gbps, twice as high as USB 3.
This lift is not very long, or even a bit of chicken ribs. On the one hand, most USB devices use less than 3 of the limit. On the other hand, if we really need more bandwidth, it is still not enough for such a promotion. For example, the USB device can now to the limit, the most common is the mobile SSD, but it is SATA3 to 3 USB, the bandwidth of 6Gbps to 5Gbps, is also a little loss, but turned into a 6Gbps 10Gbps (SATA3 USB3.1 Gen 2) also did not have much change, that bottleneck is not the interface version, but the performance of switching chip.
It is also necessary to say if there is any 10Gbps that can be embodied. Before that, there were 2 M.2 solid state groups RAID 0 before switching to USB 3.1 Gen 2, which is much faster than USB 3.1 Gen 1. But it still has little meaning, and there are few normal people in use.
The coding standard changes from 8b/10b to 128b/132b, which greatly reduces the coding loss rate.
The original USB3.0, each transmission of 10bit data, actually contains only the "real data" of 8bit, which is done to balance the signal DC. The visual result is the loss on the bandwidth, and the actual load is only 80%, and the coding loss rate is 20%.
And USB3.1 raises the coding standard to 128b/132b, so the actual load is about 97%, and the coding loss rate is only 3%.
The first feature is from 5Gbps to 10Gbps. If we calculate this feature, the actual bandwidth difference between USB 3.1 Gen 1 and Gen 2 can reach 1.42 times, that is to say, the hidden bandwidth gain is almost 50%.
In this way, it seems that the new interface has not been promoted so little...
The USB AV increases the bandwidth, and the HDMI1.4.
This function is actually available in the USB2.0 era, using the bandwidth of USB to transmit video signals. Note that with DP video output interface TypeC and lightning 3 compatible DP video is not a concept, the two root pressure is not a thing, this USB AV is using the USB bus to transmit the video signal bandwidth, while the latter is TypeC directly into "DP interface", connected with the other chip machine. Never mind with USB bus, does not occupy the bandwidth.
However, there are too few data related to this function. It seems that after the connection of the USB display, a display device will appear more. It will also delay the display. It will affect the screen display because of the lack of bandwidth.
To distinguish whether it is very simple, this function can be used to connect with TypeA interface, while the video output of TypeC can not be used. Forcing the use of the interface will prompt DP to connect the device abnormal.
The power output can reach 100W.
The above picture is the USB3.1 power supply range, it can be seen that the voltage is no longer constrained by the 5V, and 12V and 20V two gear, the maximum current can reach 5A, it is really terrible. However, considering the power supply capability of motherboard, this specification is only "able to achieve" now. If every USB interface has power supply capability, I'm afraid the power adapter of laptop will explode.
To support such a high power consumption, it also needs USB PD (USB Power Delivery power transfer protocol), which is provided by extra chips, and naturally no machine can support such a high power. It is also estimated that a certain USB3.1 interface (some TypeC) of a part of the machine can support greater power output, and the possibility of reaching 100W is extremely low.
TypeC, as a new interface after USB3.1, naturally supports all of the features mentioned above, not only that, but also its exclusive features:
Support positive and negative inserts.
Although all past generations of USB have anti - plug and anti - design, but this can not prevent the "great miracle" after the tragedy... So this time to solve the problem from the source, both positive and negative insertion can be used, and will never encounter the embarrassment of inserting in the USB.
As shown in the picture, typeC has 24 pins and 12 on each side. When there is no connection, the pin definitions on both sides are centrally symmetric, so the typeC positive and negative insert is a case. Of course, this definition is not always the same, and the connection will change according to the identification.
Here, the TypeC and USB 3.1 scientific knowledge about almost, everybody look again cannot understand, never mind, I am also, who is nothing to put these into the mind......
But before closing the window and so on, I need to emphasize one thing:
All of the above features, the TypeC interface is all configurable.
Many of the mobile phones now use the TypeC interface, but in fact, the USB can only reach 2. The entry-level game and most TypeC super book, usually only USB3.0, can support DP video output, only a handful of the 3 to support high-end lightning and other characteristics, but the manufacturer will never give you the support does not support the TypeC to introduce you to all.
So the question is, what are the functions of the Type-C on a device?
Some compliant PC vendors will print support functions beside the USB interface. For example, USB 3.1 Gen2 will write "10G", and thunder 3 will be like this.
Note, however, that the logo is not a complete "lightning" symbol, with an arrow mark at the end.
Some TypeC interface will mark this lightning symbol, the end has no arrow, this is to support the meaning of shutdown charging, not lightning 3, do not mix.
But most manufacturers do not mark these things next to TypeC for the sake of beauty. At this point, we can only test it by ourselves.
Is it USB3.1 Gen2, a device that supports a device to see if there is a USB 3.1 controller. The name of the controller recognized by the north and south bridge can also determine whether the machine supports lightning 3. The final support for DP video can be inserted with a display.
But it is really annoying for ordinary consumers to do so, so why do you have to buy it back to know?
So, the meaning of the evaluation comes... We are also trying not to label these manufacturers, but for consumers, it is necessary to know the information and prevent them from getting into trouble because of information asymmetry.
In short, when consumers encounter "TypeC" in the future, they should remind themselves that this propaganda can not be fully believed. What functions do they really support, but also need the test of practical evaluation.