Choke (electronics)



![A
typical common-mode choke configuration. The common mode currents, I1
and I2, flowing in the same direction through each of the choke
windings, creates equal and in-phase magnetic fields which add together.
This results in the choke presenting a high impedance to the common
mode signal.[1]](/uploads/202501/04/Common-mode-choke2332.png)
In electronics, a choke is an inductor used to block higher-frequency alternating current (AC) in an electrical circuit, while passing lower-frequency or direct current (DC). A choke usually consists of a coil of insulated wire often wound on a magnetic core, although some consist of a donut-shaped "bead" of ferrite material strung on a wire. The choke's impedance increases with frequency. Its low electrical resistance passes both AC and DC with little power loss, but it can limit the amount of AC due to its reactance.