Patent · US Expired

Common bus driver complementary protect circuit

US3938008A · kind A · utility

4Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 18, 1974
Grant dateFeb 10, 1976
Priority date
Expiry dateSep 18, 1994

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K19/01855
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

An over current protect circuit for a common bus driver having a complementary pair FET output includes a pair of AND circuits responsive to the gate-source and drain-source voltages for charging separate time integrating capacitors. If a threshold charge is reached a latch is triggered, which in turn disables the driver via a NAND gate and Inverter, and discharges the active capacitor. The latch is reset by dropping the driver enable line. As an alternative, high driver current may be sensed by placing a resistor in series with each output FET and charging the associated capacitor in response to a high current through the resistor.

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