The choke is to restrict the current in certain frequency bands through the circuit, and the filter is to remove the waveform of certain frequency bands. To put it simply, the choke coil is an inductance, which can be regarded as a low-pass filter, which is connected in the line. The filter is a general term. There are low-pass, high-pass and band-pass filters. There are two forms of parallel and series connection in the circuit. in. The two are not exactly equal.
The difference is that the number of turns of the coil is different, the ones with a lot of turns are low-frequency, the ones with a few turns are high-frequency, the high-frequency is to block the high-frequency signal, and the low-frequency is to block the low-frequency signal. The working mechanism of a choke is similar to that of a transformer, and it should have the isolation\transmission capability that a transformer should have. Disassembling a network isolation transformer, you can find that they look almost exactly the same, except that they are different in size and core material, resulting in performance differences, which are used in different occasions. In other words, if the core of the choke coil is replaced with a material with high permeability and good high-frequency characteristics, it becomes an uncompromising 1:1 isolation transformer.
The choke coil is an inductive component, it has two ends, its function is to block high-frequency signals, pass low-frequency and DC signals, mostly used as filter components and AC loads. The output transformer is divided into primary and secondary, with at least four terminals. It is mostly used for impedance transformation and isolation (to prevent mutual influence between primary and secondary power supplies).