A narrow pulse-suppressing filter for input buffer

A narrow pulse-suppressing filter allows a wide pulse and blocks a narrow pulse. While existing pulse suppressing filters can block an isolated narrow pulse, they fail to stop a series of narrow pulses. Here we propose a different filter topology, which can suppress even an infinite series of narrow pulses. This is achieved by appropriately initializing the filter capacitor for every input transition edge, independent of whether the edge is successfully propagated to the output or not. Functionality of the proposed circuit is analyzed and demonstrated with Spice simulation.