Sensors for measuring current passing through a load
US6160441A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 1998 |
| Grant date | Dec 12, 2000 |
| Priority date | — |
| Expiry date | Oct 30, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05F3/242
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sensor for measuring a current passing through a load. The sensor has a power transistor having a first terminal connected to substantially constant voltage and a second terminal connected to the load. The sensor can sample a voltage difference with a variable capacitor, and a controller can be configured to cause a variable capacitor in the current sensor to have a capacitance inversely proportional to a resistance of the power transistor, whereby a charge stored on the variable capacitor is proportional to the current passing through the power transistor when the sampling switches are opened. A comparator can compare the current through the power transistor to a known reference current to generate a digital output signal. The sensor can include a power transistor, reference transistor and amplifier connected and configured so as to generate a signal on a reference line having a current of known proportion to the current passing through the load.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.