Patent · US Expired

Method and apparatus for detecting faults in differential current switching logic circuits

US4967151A · kind A · utility

14Cited by
13References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 11, 1989
Grant dateOct 30, 1990
Priority date
Expiry dateOct 11, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/3004
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A circuit for testing a differential current switching logic circuit of the type including: a bias potential, two resistors connected to the bias potential, and apparatus responsive to an input signal for sinking a first current through a selected one of the resistors so as to generate first and second differential output signals at the resistors. The circuit includes first, second, and third transistors, each having first and second terminals for conducting a current responsive to a signal applied to a control terminal. Apparatus are provided for supplying a current. The first transistor has its first terminal connected to the current supplying means, and its second terminal connected to a circuit node. The second transistor has its first terminal connected to the circuit node, its second terminal connected to the bias potential, and its control terminal connected to sense the potential at a selected one of the resistors. The third transistor has its first terminal connected to the circuit node, its second terminal connected to the selected resistor, and its control terminal connected to sense the potential at the other of the resistors. The circuit functions to sense the potentia…

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