Ayrton-Perry winding
Encyclopedia
Ayrton-Perry winding is a type of bifilar winding pattern used in winding wire on forms to make electronic component
s. Its advantage is that the resulting coil of wire has low values of parasitic inductance and parasitic capacitance
. Ayrton-Perry windings of resistance wire
are used to make wirewound RF resistor
s that are used at high frequencies, where inductance and capacitance are unwanted.
The winding is made of two separate wires wound in opposing directions along an insulating form and connected in parallel at the ends. Since there are the same number of turns of wire in either direction, the magnetic fields of the two wires cancel each other out, so the coil has little inductance. And since adjacent turns of the two wires are at approximately the same voltage, there is little parasitic capacitance between the turns.
One disadvantage is that because the two lengths of resistive wire are connected in parallel, four times the length of wire (twice the length for each coil) is needed to make a given resistance than if a single coil was used.
Electronic component
An electronic component is a basic electronic element and may be available in a discrete form having two or more electrical terminals . These are intended to be connected together, usually by soldering to a printed circuit board, in order to create an electronic circuit with a particular function...
s. Its advantage is that the resulting coil of wire has low values of parasitic inductance and parasitic capacitance
Parasitic capacitance
In electrical circuits, parasitic capacitance, stray capacitance or, when relevant, self-capacitance , is an unavoidable and usually unwanted capacitance that exists between the parts of an electronic component or circuit simply because of their proximity to each other...
. Ayrton-Perry windings of resistance wire
Resistance wire
Resistance wire is electrical wire used for its property of electrical resistance. It is routinely used at high temperatures, so normally also has high melting point....
are used to make wirewound RF resistor
Resistor
A linear resistor is a linear, passive two-terminal electrical component that implements electrical resistance as a circuit element.The current through a resistor is in direct proportion to the voltage across the resistor's terminals. Thus, the ratio of the voltage applied across a resistor's...
s that are used at high frequencies, where inductance and capacitance are unwanted.
The winding is made of two separate wires wound in opposing directions along an insulating form and connected in parallel at the ends. Since there are the same number of turns of wire in either direction, the magnetic fields of the two wires cancel each other out, so the coil has little inductance. And since adjacent turns of the two wires are at approximately the same voltage, there is little parasitic capacitance between the turns.
One disadvantage is that because the two lengths of resistive wire are connected in parallel, four times the length of wire (twice the length for each coil) is needed to make a given resistance than if a single coil was used.