Patent · US Expired

Digital oscilloscope with pan and zoom produced from time stamped data records indexed by trigger offset

US5877621A · kind A · utility

12Cited by
3References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 30, 1996
Grant dateMar 2, 1999
Priority date
Expiry dateApr 30, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R13/345
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Each acquisition record in a random repetitive oscilloscope is time stamped and stored in a location in the acquisition memory indexed by the associated value of trigger offset. Those acquisition records that are older than a selected and variable amount can be discarded instead of being used to contribute data to the waveform record. This has the effect of preventing old data from intruding into a new measurement. When reformulating the waveform record to pan or zoom while using data already acquired, it is possible to ensure that the newest waveform records are included in that reformulation. This has the effect of ensuring that new data is displayed. The time stamp may be a binary count of an elapsed time interval, in units of the sample clock, since some cardinal event, such as the last time ERASE or RESET was pressed. To maximize the random distribution of the trigger offsets represented in the acquisition memory, the rule for deciding which of m-many acquisition records receives this latest data is based on the trigger offset. The first of the acquisition records gets acquisitions whose trigger offsets are at least zero but less than 1/m of a sample period t, the second recei…

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