Patent · US Expired

BiCMOS transconductor stage for high-frequency filters

US5912582A · kind A · utility

4Cited by
9References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 30, 1997
Grant dateJun 15, 1999
Priority date
Expiry dateMay 30, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03F2203/45506
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A BiCMOS transconductor differential stage for high frequency filters includes an input circuit portion having signal inputs and a pair of MOS transistors having their respective gate terminals corresponding to the signal inputs. The differential stage has an output circuit portion having signal outputs and a pair of bipolar transistors connected together with a common base inserted between the inputs and the outputs in a cascode configuration. The differential stage includes a switching device associated with at least one of the bipolar transistors to change the connections between parasitic capacitors present in the differential stage. The switching device also has at least one added bipolar transistor connected in a removable manner in parallel with the corresponding bipolar cascode transistor. In a variant differential stage, there are also provided respective added MOS transistors connected in parallel with the MOS transistors of the input circuit portion to change the ratio W:L of each of the MOS transistors.

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