Patent · US Expired

Current generator circuit having a wide frequency response

US5874852A · kind A · utility

7Cited by
5References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 30, 1996
Grant dateFeb 23, 1999
Priority date
Expiry dateAug 30, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05F3/267
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A current generator circuit with controllable frequency response has at least one current mirror formed of MOS transistors, being powered through a terminal held at a constant voltage, having an input leg through which a reference current (I1) is driven by a first current generator (G1), and having an output leg for generating, on an output terminal (OUT) of the mirror, a mirrored current (I.sub.out) which is proportional to the reference current (I1). The input leg includes at least a first transistor (M1) which is diode-connected and has a control terminal (Ga1) coupled to a corresponding terminal (Ga2) of a second transistor (M2) included in the output leg by an impedance matching circuit configured to hold the same voltage value at both terminals (Ga1 and Ga2). The impedance matching circuit has an adjustable output impedance, specifically lower in value than the value to be had without this circuit. It functions to regulate the impedance on the control node (Ga2) of the second transistor (M2). The invention is equally applicable to N-channel and P-channel MOS transistors. Advantageously, the reference current can be varied by an external signal which is a function of the outpu…

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