Battery charger status monitor circuit and method therefor
US5376875A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 3, 1993 |
| Grant date | Dec 27, 1994 |
| Priority date | — |
| Expiry date | Dec 3, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J7/007182
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A battery charger status monitor circuit (40) for monitoring the status of a battery (12) charged with current pulses. The current pulses charging the battery (12) are reduced in frequency and duty cycle as the battery approaches a fully charged condition. By monitoring the number of current pulses charging the battery within a predetermined time period, the charge status of the battery (12) is determined. If no pulses are detected within the predetermined time period, the battery (12) is fully charged. A counter (47) is incremented by a clock signal. A charge signal resets the counter (47). The charge signal corresponds to the current pulses charging the battery. If the counter (47) reaches a predetermined count, the clock and charge signals are disabled. Reaching the predetermined count before resetting indicates the battery (12) is fully charged. When the counter is below the predetermined count, the battery (12) is being charged.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.