Patent · US Expired

Polyphase reference generator

US4327420A · kind A · utility

6Cited by
4References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 30, 1980
Grant dateApr 27, 1982
Priority date
Expiry dateJun 30, 2000

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F1/0342
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A reference generator, providing a plurality of precisely-phased output signals, utilizes a microprocessor having a table of values for the output waveforms stored in a read-only memory thereof. The table entries include a multiplicity of values for providing a stepwise representation of each of the desired waveforms, which may have constant angular increments therebetween. The incremental tabular values are consecutively read responsive to the count in a timer, integral in the microcomputer, which is sequentially advanced by the pulse output of a voltage-to-frequency converter receiving a rate signal. The tabular values are converted to analog polyphase reference signals by a like number, equal to the number of phases, of digital-to-analog converters and associated low-pass filters. The output waveform peak amplitude is established by a dual-polarity reference voltage generator, responsive to a variable level signal. Essentially instantaneous reversal of the polyphase waveforms is provided by "angle complement" control of the present point utilized within the tables. The timer circuit provides steps of increasing size through the lookup-table to provide a gradual degradation in th…

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