Patent · US Expired

Binary digitizer circuit for voltages developed across induction coil

US4972095A · kind A · utility

7Cited by
4References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 6, 1989
Grant dateNov 20, 1990
Priority date
Expiry dateSep 6, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01P3/4802
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A pulse shaper is disclosed which shapes a vehicle speed signal developed by a tachometer and pulsating with a frequency which is proportional to a vehicle speed into a rectangular wave pulse. A reference potential line is biased above a common potential. The vehicle speed signal has its level clamped to a range from 0.6 V below to 0.6 V above the potential of the reference potential line. A first IC comparator digitizes the clamped speed signal into a binary form around the potential of the reference potential line. When the reference potential line becomes short-circuited to the common potential. The clamped vehicle speed signal which is applied to the inverting input of the first comparator reduces below the common potential, giving rise to the likelihood of an erroneous pulse. A second IC comparator then detects a reduction in the potential of the reference potential line to constrain the output of the first comparator to an L level, preventing an erroneous pulse from being delivered.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.