Patent · US Expired

Output driver with level shifting and voltage protection

US5736869A · kind A · utility

62Cited by
11References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 16, 1996
Grant dateApr 7, 1998
Priority date
Expiry dateMay 16, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K19/00315
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An output driver circuit according to the present invention provides level shifting and self-biased voltage protection. The output driver circuit includes first and second complementary data terminals, an output terminal. A pull-up and a pull-down transistor are coupled to the output terminal and have first and second control terminals, respectively. The second control terminal is coupled to the second data terminal. A differential transistor pair has control terminals coupled to the first and second data terminals, respectively, and defines first and second current paths. A cross coupled transistor pair is coupled in the first and second current paths and has a control output terminal coupled to the control terminal of the pull-up transistor. A self-biased voltage protection transistor is coupled between the pull-up transistor and the output terminal and has a control terminal coupled to the second current path, between the differential transistor pair and the cross coupled transistor pair. The output driver circuit can be adapted to provide 3.3V drive capability in a 2.5V fabrication process or 5.0V drive capability in a 3.3V fabrication process, for example.

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