Patent · US Expired

Differential comparator powered from signal input terminals for use in power switching applications

US5187396A · kind A · utility

90Cited by
6References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 22, 1991
Grant dateFeb 16, 1993
Priority date
Expiry dateMay 22, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K17/693
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A differential comparator is provided for controlling two switches (40) and (42) to switch two supplies (10) and (12), respectively, to a common output node (22). The decision/control circuit (44) outputs two control signals (46) and (48), the logic state thereof being a function of whether supply (10) is higher than supply (12) or supply (12) is higher than supply (10). The operating power for the decision/control circuit (44) is derived from the supplies (10) and (12), and not from the common output node (22), such that when the switches (40) and (42) are closed and no power is being supplied by either of the supplies (10) and (12), the decision/control circuit (44) has sufficient power to make a decision.

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