Current sensing circuit
US4713607A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 23, 1985 |
| Grant date | Dec 15, 1987 |
| Priority date | — |
| Expiry date | Dec 23, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K1/0268
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A current sensing circuit senses current and signals if such current exceeds a predetermined level within an etched circuit board. The circuit comprises a conductive trace of a predetermined resistance within a metallization layer of the board and a reference voltage circuit and comparator coupled to the trace. The reference voltage circuit senses voltage at first sense point on the trace and offsets the voltage a predetermined amount to form a reference voltage. The comparator senses voltage at a second sense point on the trace and compares it to the reference voltage. So long as the second voltage exceeds the reference voltage, the comparator indicates that the current is below the predetermined level. If the second voltage drops below the reference voltage, the comparator generates an output signal indicating that the current has exceeded the predetermined level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.