A filter is an electronic device that can filter and separate the frequency components of a signal. It is widely used in many fields such as electronic engineering, communications, and electricity. The following is a detailed introduction for you:

Working Principle:

The working principle of the filter is based on the fact that circuit elements (such as resistors, capacitors, and inductors) present different impedance characteristics to signals of different frequencies. Capacitors have a smaller impedance to high-frequency signals and a larger impedance to low-frequency signals; inductors are the opposite, with a smaller impedance to low-frequency signals and a larger impedance to high-frequency signals. By combining these components reasonably, various types of filters can be constructed to allow signals within a specific frequency range to pass smoothly while suppressing or attenuating signals of other frequencies.