Patent · US Expired

One-terminal type level control circuit

US4476426A · kind A · utility

4Cited by
1References
7Claims
0Family size

Assignees

Inventors

Key dates

Filing dateJun 3, 1982
Grant dateOct 9, 1984
Priority date
Expiry dateJun 3, 2002

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H9/046
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A constant-current source transistor, which exhibits a constant-current characteristic corresponding to the power source voltage of a sensor and is connected to an input signal terminal of an input circuit, such as a microprocessor. A first transistor is connected so that it may supply a current from the power source of the input circuit to the constant-current source transistor, and a second transistor is connected in parallel to the constant-current source transistor. When the signal level at the input signal terminal exceeds a predetermined value, the second transistor is turned ON to effect level control so the input signal level may not become excessively high and damage the input circuit.

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