Integrated circuit current reference
US6448811B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 2, 2001 |
| Grant date | Sep 10, 2002 |
| Priority date | — |
| Expiry date | Apr 2, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/0005
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A current reference with reduced sensitivity to process variations includes a variable resistor and a control transistor. The control transistor has a generated current from source-to-drain that first passes through the variable resistor. The control transistor has a reference voltage applied to the gate, and the source-to-gate voltage is a function of the reference voltage and the voltage drop across the variable resistor. A control loop circuit measures the generated current and modifies the resistance value of the variable resistor in response. An external precision resistor is used to measure the generated current, and current variations as a result of process variations are reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.