Charge/discharge control circuit and chargeable electric power source apparatus
US5742148A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 17, 1993 |
| Grant date | Apr 21, 1998 |
| Priority date | — |
| Expiry date | Nov 17, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A chargeable power supply which has a charge/discharge control circuit is provided in which the service life of a secondary cell is prolonged. A voltage dividing circuit, an overcharge voltage detection circuit, an overdischarge detection circuit and a control circuit are connected in parallel to the secondary cell. The control circuit receives signals indicating the condition of the secondary cell from the overcharge/overdischarge voltage detection circuits and outputs a signal for controlling a switch circuit for disconnecting the secondary cell from external equipment, or to stop a charging operation by an external power source. The control circuit also controls a switching element provided in series with the voltage dividing circuit and reduces a current which flows through the dividing circuit. A current limiting means is provided to limit the current consumption of the charge/discharge control circuit. In one embodiment, a the current limiting device is a switching element provided in series with the voltage dividing circuit. In another embodiment, the current limiting device is an error amplifier with a latching function provided in an overcharge detecting circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.