CHOKES

Choke is an inductor used to block high-frequency while passing direct current and low-frequency of alternating current in an electrical circuit. A choke usually consists of a coil of insulated wires often found on a magnetic core, although some consist of a donut-shaped "bead" of ferrite material string on the wire. The choke's impedance increases with frequency. Its low electrical resistance passes both AC and DC with little power loss, but its reactance limits the amount of AC passed.

The name comes from blocking—"choking"—high frequencies while passing low frequencies. It is a functional name; the name "choke" is used if an inductor is used for blocking or decoupling high frequencies, but the component is simply called an "inductor" is used in electronic filters or tuned circuits. Inductors designed for use as chokes are usually distinguished by not having the low-loss construction required in inductors used in tuned circuits and filtering applications. Its types are