Binary weighted thermometer code for PVT controlled output drivers
US6509757B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 2, 2001 |
| Grant date | Jan 21, 2003 |
| Priority date | — |
| Expiry date | Aug 2, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M7/02
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A binary weighted thermometer code is employed to adjust the output impedance of a variable impedance output driver circuit. The driver circuit includes an impedance network comprising a plurality of resistive devices each programmably electrically connectable in parallel between a first voltage source and the signal pad. The resistive devices are partitioned into a plurality of sets. A first set of the resistive devices may be programmed in a binary incremental manner to electrically connect one or more of the resistive devices in the first set between the first voltage source and the signal pad. Only if all of the resistive devices in the first set are activated may a second set of the resistive devices be programmed in a binary incremental manner. Additional sets of the resistive devices may be likewise programmed only after all of the resistive devices in the previously programmed sets are activated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.