Patent · US Expired

Circuit for controlling current switching in multiple inductive loads, with single current detector, particularly for windings of step motors

US4928049A · kind A · utility

9Cited by
6References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 16, 1988
Grant dateMay 22, 1990
Priority date
Expiry dateSep 16, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02P8/12
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

The circuit controls current switching in multiple inductive loads (L1, L2, L3, L4) fed by means of respective switching switches (SW1, SW2, SW3, SW4) and by means of respective current adjustment switches (SWA, SWB), and comprises a single sense resistor (R) in series to said switching switches, and a single comparator circuit (C, FF) adapted to generate a logical signal (Q) when the voltage across the sense resistor exceeds a reference voltage (V.sub.ref), which drives a plurality of AND gates (PA, PB) which control said adjustment switches and the second inputs whereof are driven by respective square-wave signals in opposite phase with a period equal to twice the switching period.

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