Patent US 4,032,798

A digital electrical pulse filter which provides output electrical pulses directly corresponding to input electrical pulses when the input pulses have a repetition rate greater than a predetermined repetition rate and which provides no output pulses when the input pulses have a repetition rate less than the predetermined repetition rate. An electronic energy consumption meter employing such a low cutoff digital pulse filter is also disclosed as well as a specific circuit for the filter employing complementary pairs of C-MOS active elements in an arrangement which facilitates construction of the entire filtering circuit according to C-MOS integrated circuit construction techniques and which enhances the overall operation of such an integrated circuit filter.