Current sensing amplifier
US6191989A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 7, 2000 |
| Grant date | Feb 20, 2001 |
| Priority date | — |
| Expiry date | Mar 7, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C2207/063
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A current sensing amplifier for detecting a small current difference between a pair of variable resistance loads comprises a first amplifier and a second amplifier. The first amplifier comprises a voltage clamp including first and second outputs, the voltage clamp being coupled to the pair of variable resistance loads and substantially fixing a predetermined voltage across the variable resistance loads, the voltage clamp transferring the measured current difference to the first and second outputs. The first amplifier further includes a differential current source coupled to the first and second outputs. The second amplifier includes first and second inputs and an output, the first and second inputs being coupled to the first and second outputs, respectively, of the first amplifier. The current sensing amplifier detects small positive and/or negative differences in current developed between two variable resistance loads and converts the current difference into an output signal commensurate with standard CMOS logic levels. Sensing speeds are improved further by equalizing predetermined internal nodes of the sensing amplifier prior to sensing a new signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.