Patent · US Expired

Battery monitoring circuit for operating with high battery discharge rates

US5357203A · kind A · utility

38Cited by
60References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 8, 1992
Grant dateOct 18, 1994
Priority date
Expiry dateJul 8, 2012

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02E60/10
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A battery detect circuit (32) is connected to the battery with the current input to the battery and extracted from the battery measured with a sense resistor (50) and then converted to charge and discharge pulses with a V/F converter (52). A microcontroller (64) is operable to increment a Nominal Available Charge (NAC) register (180) during a charge operation, and to increment a Discharge Count Register (DCR) (184) during a discharge operation. The NAC register (180) indicates the available charge, which value is output to a display (34). The maximum value to which the NAC value can rise is limited by a value stored in the last measured discharge register (182). This value represents the value stored in the DCR (184) whenever the battery is discharged from an apparent full state to a fully discharged state. This results in a qualified transfer to the LMD register (182) such that no knowledge of the actual battery charge is necessary. The microcontroller (64) is operable to determine the rate of discharge corresponding to the voltage across the sense resistor (50). When the rate of discharge exceeds a predetermined discharge rate, the operation of the microcontroller (64) is partial…

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