Calibration methods and circuits for optimized on-die termination
US6924660B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 8, 2003 |
| Grant date | Aug 2, 2005 |
| Priority date | — |
| Expiry date | Sep 8, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/0298
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Described are on-die termination (ODT) systems and methods that facilitate high-speed communication between a driver die and a receiver die interconnected via one or more signal transmission lines. An ODT control system in accordance with one embodiment calibrates and maintains termination resistances and drive currents to produce optimal output swing voltages. Comparison circuitry employed to calibrate the reference resistance is also used to calibrate the drive current. Termination elements in some embodiments are divided into two adjustable resistive portions, both of which are designed to minimize capacitive loading. One portion is optimized to produce a relatively high range of adjustment, while the other is optimized for fine-tuning and glitch-free switching.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.