Jumpers and DIP Switches
In electronics and particularly computing, a jumper is a short length of conductor used to close a break in, or bypass part of, an electrical circuit. Jumpers are typically used to set up or adjust printed circuit boards, such as the motherboards of computers.
Jumper pins (points to be connected by the jumper) are arranged in groups called jumper blocks, each group having at least one pair of contact points. An appropriately sized conductive sleeve called a jumper, or more technically, a jumper shunt, is slipped over the pins to complete the circuit.
Jumpers must be electrically conductive; they are usually encased in a non-conductive block of plastic for convenience. This also avoids the risk that an unshielded jumper will accidentally short out something critical (particularly if it is dropped on a live circuit).
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A DIP switch is a manual electric switch that is packaged with others in a group in a standard dual in-line package (DIP). The term may refer to each individual switch, or to the unit as a whole. This type of switch is designed to be used on a printed circuit board along with other electronic components and is commonly used to customize the behavior of an electronic device for specific situations.
Dip switches are an alternative to jumper blocks. Their main advantages are that they are quicker to change and there are no parts to lose. They are not used these days.
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