Adapters and Converters – CompTIA A+ 220-1001 – 3.1


As a technologist, you’ll often need to connect two systems that don’t share the same interfaces. In those situations, you’ll need an adapter or converter to connect video displays or network links.

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If you worked long enough with technology, you will be in a circumstance where you just don’t have the right type of cable or the right type of connection. In those scenarios, you may want to try using an adapter to be able to give you the interface that you need.

Adapters apply to convert from one interface type to another as long as those interface types are compatible. You might also need to use a converter if there are two interfaces that are not electrically compatible and you need to convert from one format to another. Once these adapters or converters are in place, that can be used temporarily or as a permanent connection between devices.

One type of adapter you might use for video is when you need to convert from a digital DVI connection to an HDMI connection. HDMI and the digital versions of DVI are electrically compatible, so you don’t have to perform any type of signal conversion, there’s no power required for this connection, you need simply an HDMI connection on one end and a DVI digital connection on the other.

You could even do this with a simple adapter with no cable at all that has the DVI digital connection on one side, and then on the other side of this adapter is an HDMI interface. Another type of adapter used for analog video is one that might convert from a VGA connection to a DVI analog connection.

This DVI analog is backwards compatible with VGA, but it’s only guaranteed to be compatible running at resolutions of 640 by 480. One nice feature when converting between VGA, which is analog signals, to a DVI analog, which obviously is also analog, is that you don’t need to perform any type of conversion. If you’re moving from VGA to the digital version of DVI, then you will need to use some type of converter, usually a power device that will perform a conversion of those signals.

Here’s the single adapter that has a 15-pin VGA connection on one side of the adapter, and on the other end of the adapter is the DVI analog connection. One of the things you may have noticed with newer laptops is they don’t tend to have physical ethernet interfaces as part of the laptop. Those interfaces are almost too large these days for our smaller, thin type of laptop.

In those cases, you may want to have this type of converter available, which plugs into a USB connection and provides you with a wired ethernet connection on the other side. If you’re managing switches or routers that need this physical ethernet connection, or you’re on a network that doesn’t have a wireless option, you may want to make sure you have one of these converters in your bag.