Impedance control circuit
US6573746B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 1, 2001 |
| Grant date | Jun 3, 2003 |
| Priority date | — |
| Expiry date | Jun 1, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05F1/46
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An impedance control circuit that reduces the impedance variance when an external impedance generated from an external resistor is matched to internal impedance. In one aspect, an impedance control circuit comprises an external resistor for establishing a first reference voltage; a comparator for comparing the first reference voltage with a second reference voltage and outputting an impedance corresponding to the result of the comparison; and a PMOS current source connected to a constant-voltage source and to the output of the comparator, wherein the PMOS current source generates a current that corresponds to the impedance of the comparator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.