Short pulse width noise immunity discriminator circuit
US4471235A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 3, 1982 |
| Grant date | Sep 11, 1984 |
| Priority date | — |
| Expiry date | May 3, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R29/0273
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A circuit is described for discriminating relatively wide, high level signal pulses from relatively narrow and/or low level noise pulses. The input pulses are first passed through a first Schmitt trigger to eliminate low level noise pulses. The output of the first Schmitt trigger is connected to a signal input of a "D" latch and to one input of an exclusive NOR gate. The exclusive NOR gate compares the input pulses from the output of the first Schmitt trigger with an output of the latch through a second Schmitt trigger. An R-C integrating network connected between the exclusive NOR gate and the second Schmitt trigger produces a rising input signal to the second Schmitt trigger that reaches the threshold level of the Schmitt trigger only for input signal pulses that exceed a given pulse width.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.