Integrated circuit current reference
US6737909B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 26, 2001 |
| Grant date | May 18, 2004 |
| Priority date | — |
| Expiry date | Nov 26, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R35/007
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A current reference with reduced sensitivity to process variations includes a variable resistor and a control transistor. The control transistor has a current from source-to-drain that is provided by a current mirror. The current mirror also provides a current to a variable resistor that is coupled gate-to-source to the control transistor. A control loop circuit measures the reference current provided by the current mirror and modifies the resistance value of the variable resistor in response. An external precision resistor is used to measure the reference current, and current variations as a result of process variations are reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.