Signal filters block or decrease (attenuate) unwanted frequencies or signal wave characteristics

RF filters and microwave filters are devices that pass or reject signals by frequency.

Electromagnetic (EMI) filters and radio frequency interference (RFI) filters purify signals by attenuating the high-frequency RFI (typically 150kHz and up) and passing the low frequency EMI

Active low pass filters pass signals from low frequencies and reject signals from high frequencies

Active band pass filters are used to attenuate frequencies below and above a range of frequencies (i.

IC electronic filters are frequency-selective circuits that consist of devices such resistors, capacitors, inductors, transistors, or operational amplifiers coupled with reactive components

Digital filters use digital signal processing (DSP) to perform numerical calculations on sampled values of a signal