Patent · US Expired

Battery charger with microprocessor control

US5198743A · kind A · utility

45Cited by
12References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 11, 1990
Grant dateMar 30, 1993
Priority date
Expiry dateDec 11, 2010

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02J2207/20
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A battery charger has battery terminals connected to a conventional wall outlet through a switching power supply to provide a direct conductive non-isolated path from the supply for direct transformer-less supply of charging current to a battery. Pulse width modulated signals are applied to a MOSFET of the power supply from an output port of a microprocessor which is operates a ramp generator and responds to a comparator circuit coupled to a battery voltage sense circuit and the ramp generator. The microprocessor is programmed to accurately control generation of the pulse width modulated signals, to shut off current when a true voltage peak is reached at a full charge condition, to avoid response to false peaks, to cut off current for short time intervals during voltage measurements, to perform an exponential averaging function and to shut down at excessive battery temperatures or time rates of change of battery temperature.

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