Double filtering glitch eater for elimination of noise from signals on a SCSI bus

摘要

A glitch filter for eliminating noise pulses less than 12 nanoseconds (ns) created by large devices on the SCSI bus and reflections of the 12 ns pulses created by a long SCSI bus cable, as well as noise pulses on the order of 35 ns typically found on a SCSI bus. The glitch filter includes a Schmitt trigger connected to receive the SCSI bus signal along with three filters connected in series with the Schmitt trigger. The first filter removes positive pulses having a pulse width less than 12 ns and provides an inverted output. The second filter removes negative pulses having a pulse width less than 12 ns and provides an inverted output. The third filter removes pulses having a pulse width less than 35 ns and provides the output of the glitch filter.