Two terminal I.C. magnetic-field detector for use in a liquid level sensor and having an anti-slosh feature
US5686894A · kind A · utility
Inventors
Key dates
| Filing date | Jan 3, 1996 |
| Grant date | Nov 11, 1997 |
| Priority date | — |
| Expiry date | Jan 3, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/9517
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A two-terminal integrated circuit magnetic-field detector, for use in detecting a low level of a liquid in a vehicle, has a Hall element, a Schmitt type comparator, an anti-sloshing accumulator such as an up-down counter, and a latching driver all connected in tandem. The anti-sloshing accumulator is for producing a signal that is the integral as a function of time of the binary comparator output signal. During sloshing, when the average liquid level is near that at which a low-level warning signal is desired, the accumulator signal climbs in a vacillating manner. The latching driver is connected across the two integrated circuit (I.C.) terminals and latches on when the accumulator signal reaches a predetermined value, dropping the impedance across the two I.C terminals. A liquid level indicating lamp is connected in series with a source of DC voltage and the two I.C. terminals, so that when the average position of the floating magnet approaches that of the I.C. detector, the driver latches on and the low-level indicating lamp is also turned on and cannot be turned off except by removing the DC energizing voltage. The accumulator may be an up-down counter with means for preventing …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.