What is a low pass filter, what does it do in an electrical circuit?
Answer A low pass filter is an electronic circuit which allows low frequencies to pass through while blocking high frequencies. There are many, many kinds of circuit configurations that will do this and it depends on the application as to which filter design would be used. The most simple low pass filter is a series resistor and a shunt capacitor or a series inductor and a shunt capacitor. Either one will provide a 6 db per octave roll off of the high frequencies above the cutoff frequency determined by the RC or LC time constant.
