Patent · US Active

Impedance calibration circuit and method

US8581619B2 · kind B2 · utility

6Cited by
6References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 25, 2011
Grant dateNov 12, 2013
Priority date
Expiry dateAug 25, 2031

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L25/0298
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

An embodiment includes an impedance calibration circuit having a calibrator configured to compare voltage levels at an external node and an internal node of the impedance calibration circuit and to generate an output based on the comparison. The calibrator further includes respective filters coupled between the external node and a first input of the comparator, and between the internal node and a second input of the comparator. The filters are configured for symmetric noise injection into the comparator from a chip ground line to which a programmable resistor at the internal node is coupled.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.