After you select a display device, you then have to determine how to connect it to your computer, and we often have many options to choose from. In this video, you’ll learn about the different video connectors and how to connect them to your display device.
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If you’ve worked a lot with DVI, you’ll notice there are a number of different interface types. DVI stands for Digital Visual Interface. And it’s a very standard interface to use these days, especially on our higher resolution displays.
There are two kinds of DVI. There is a single link and there is a dual link. This does not refer to the number of cables that you’re using. It refers to the amount of signal that is passing through a single cable.
If it is a single link connection, then it is sending 3.7 Gbps of traffic. That is referring to enough so that you could send HDTV signals at 60 frames per second. Sometimes you need more data to be sent through. Those are sent over dual link connections, that is 7.4 Gbps, effectively twice as much, that’s able to do HDTV at 85 frames per second.
If you’re working with an analog signal over DVI, it’s going to look like this connection at the top, which is a DVI-A. That “A” stands for analog. Conversely, there are digital signals on a DVI-D, that “D” being for the digital connection. And there are both single link and dual link connections for the DVI-D.
And lastly, there is an integrated type, called the DVI-I, where I could send digital and analog signals in the same connection. And you can see the two different types of single link and duel link connections here for DVI integrated.
Another type of display connection that you’ll see for video is the DisplayPort. this is a standard that is from the Video Electronics Standards Association. What’s nice about the standard is it’s royalty-free. So implementing this type of connection in your computer, in your laptop, the manufacturers don’t have to pay a fee for doing that.
There is data sent across this that is sent in packetized form. This is very much like sending data to a PCI Express or sending data across an ethernet connection. It’s simply taking the digital signal and sending packets over this particular connection.
This is also a connection type that’s compatible with HDMI. It’s compatible with DVI. All you have to do is put a very simple passive connector on the end and you can also connect to those types of interfaces.
You may see different form factors for DisplayPort interfaces. These are two of the common ones. This is the standard DisplayPort. And here’s the DisplayPort you often see on Apple devices called a mini DisplayPort.
We often associate HDMI with television. But of course, it could also be used for computers as well. One nice thing about HDMI is that you could send those video and audio over exactly the same cable. This is a completely digital connection. You do not send analog signals over an HDMI cable.
With most large devices, we tend to see this large 19-pin, what we call a Type A connector for HDMI. HDMI is a standard that requires that a payment be made to use it, something that has to be a licensed. So this is not a free connector that a manufacturer can use. It is a proprietary type of connection.
You might also find mini HDMI, especially on smaller devices. What we call this is a Type C connector. And it’s really designed for much smaller form factors. There’s even a micro HDMI that’s a Type D. There’s even smaller versions of that, that you can fit onto the very, very small portable devices as well.
A video display connection that’s been around for seemingly forever is a VGA connector. You see it normally packaged in this DE-15, this 15-pin connector. You may also see it written as DB-15, although that would be a much wider connector. But both of those are generally acceptable to describe this type of video connection.
It’s also almost always colored blue. This is a standardized coloring scheme from the PC System Design Guide that the industry uses. So often on the back of your computer, you’ll notice that the interface for VGA is colored with a blue color.
A VGA connection outputs an analog video signal. You may notice this if you try to take a video display and extend that VGA out over a long distance. You may notice ghosting or information not quite looking right on the other side, because there’s signal loss along the way. And unlike a digital connection where you either get the signal or you don’t get the signal, with an analog connection, on the other end, you simply get a degraded display that does not look quite as crisp as it should.
We see RCA connectors used for both audio and video. It’s a connector type that’s been around since the 1940s. Sometimes, you’ll see it refer to as a phono connector.
An RCA connector is very commonly used for composite video. A composite video uses a single link, usually it’s a bright yellow. We can see it right on here as that single composite video. It’s often used in conjunction with audio. So you may also be running a left and right, red and white, audio signal along with the yellow video signal.
RCA interfaces are also used to send component video to another connection. You can see the three component video connectors on the top of this device. And they’re marked Y, PB, and PR. The Y stands for luminance. It’s the amount of brightness of the signal. The PB stands for blue and the PR stands for red.
And these are usually used for higher definition. And you’ll see that the colors are very much the same when we look at them. The green is the Y, and then the PB for the blue, and the PR for the red. And all you have to do is match those up on the back of your device and you’re generally sending high-definition signals down those connections.
A type of connection you commonly see in more industrial type environments is a BNC connection. That stands for Bayonet Neill-Concelman And it was Paul Neill and Carl Concelman who came up with this type of connector. It uses that bayonet, which means that you push it in and you turn it and it locks. It’s very difficult to pull that out, unless you then push it in and turn it to be able to get it out of that connection.
And it’s used primarily on higher-end video, where you have to make sure it’s always connected. You want to be sure doesn’t accidentally slip out of that connection there. Generally we see this being used with RGBHV, where the green, the red, the blue, the horizontal sync, and the vertical sync are all sent over different wires. You can also see this being used on component video as well, where you still have that Y, the PB, and the PR, and sending all three of those connections with that connector on the end that slides in on the bayonet and locks in the place.
A video type that uses a MiniDIN-6 connector is one called Separate Video. It’s abbreviated S-Video. It’s an analog video type. It’s not commonly used these days. But you’ll certainly see on legacy devices.
And it has two channels, one for intensity and one for color. This is usually used for lower resolution and lower definition pictures. But it’s one that provides the single cable just for the video.
In large data centers, it’s not uncommon to see video being sent over twisted pair, using these RJ45 connectors. You see this a lot when you need to extend a video from many different devices that might be in a rack, all the way back to something like a keyboard, video, mouse extension. That way, you can have a central console in your data center. And over a single RJ45 CAT 5-type cable, you can send all of those signals, the keyboard, the mouse, and the video, to any of the devices in your environment. And when you’re dealing with that many devices in a large data center, being able to use an existing infrastructure like RJ45 makes the job very, very easy.