Current-level monitor with hierarchical precision
US6014030A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 1998 |
| Grant date | Jan 11, 2000 |
| Priority date | — |
| Expiry date | Mar 30, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R19/16542
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Current-level monitoring circuitry incorporating a full-time coarse monitor and a part-time fine monitor and capable of generating control signals when the current-level being monitored reaches certain predetermined thresholds. In its preferred embodiment the invention is incorporated into battery-protection circuitry, guarding against both excess charging currents and excess discharging currents. A key concept of the invention is a hierarchical monitoring system incorporating a full-time coarse monitor that activates the fine monitor only when the battery current level enters a certain range and then deactivates it once the level falls out of that range again. Should the current level continue to rise up to the threshold of unsafe battery current, the fine monitor will disconnect the battery. In the preferred embodiment of the invention, the fine monitor operates by comparing, with a predetermined reference voltage, the voltage drop across a fine sensing resistor through which battery current is directed. The fine sensing resistor may be a precision resistor or it may be the same resistance used by the coarse monitor. The reference voltage is established in a way that permits a di…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.