Plug-in card
A plug-in card (also known as an expansion card or electronic card ) is a printed circuit board equipped with electronic components that can be easily replaced. This is made possible by plug connectors and, if necessary, further mechanical elements for handling and fastening in the slot .
Such modular systems usually also have a motherboard . If it is only used for electrical connection, it is referred to as a backplane . Often only plug connectors were installed that were wired together using winding technology .
Form factors
In order for plug-in cards to fit into an existing plug-in system and work there, on the one hand they must meet the mechanical specifications (so-called form factor , i.e. external dimensions and connector arrangement), and on the other hand the electrical parameters, i.e. the pin assignment and the signal specification, must also be observed.
In addition to plug-in cards for PCs , there was and still is a whole range of other standardized plug-in card formats. Examples are the European map and the 19-inch assembly system according to DIN 41494 or the PXI system.
Application in the computer field
IBM compatible personal computers are the most common type of computer. These usually have expansion slots into which electronic circuit cards with a specific format can be inserted. They can be replaced, removed and added, but they must be compatible with the respective expansion bus of the device. This allows the computer to support more functions than it originally offered.
Some examples of these interfaces are:
A list of typical bus systems can be found in the article Bus (data processing) .
Plug-in cards can have various functions, such as: B. a graphics card that converts data so that the monitor can output it as an image.
There are three different types of PCI cards. Full-length, full-length PCI cards are 107 mm (height) × 312 mm (length). Half-length, half-length PCI cards are 106.68 mm (height) × 175.26 mm (long) and "low profile" - also called "slim" PCI cards. Low-profile PCI cards range from 64.41 mm × 119.91 mm to 64.41 mm × 167.64 mm.
In many computer motherboards, some functions are already integrated, so there is no need to use an expansion card for the respective function. The use of an expansion card is almost always possible without any problems. Widespread so-called on-board solutions are: sound, graphics, network and mass storage controllers.
The connector systems listed so far are all used internally in the computer. An example of an external plug-in card is the PC card , as it is mainly used in notebooks .
There are also computer systems that are made up entirely of plug-in cards, where the CPU is also located on a plug-in card ( slot CPU ) and the backplane has purely passive connection functions. One example of this is the VMEbus , which is used in particular in modular measuring and testing systems.
Examples
adapter
- A riser card , for example, serves as an elbow to adapt form factors.
Other uses
Plug-in cards can also be used in other electronic devices. However, these are usually manufacturer-specific and do not follow a general standard.
They can be used to simplify the maintenance and repair of complex electronic systems - e.g. B. in televisions .
Another application is the expandability of such systems, e.g. B. in telecommunications systems.
Web links
Individual evidence
- ↑ Mechanical specifications of low profile PCI cards (PDF file; 97 kB)