Patent · US Expired

Power-On-Reset (POR) circuit

US4788462A · kind A · utility

21Cited by
5References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 12, 1987
Grant dateNov 29, 1988
Priority date
Expiry dateFeb 12, 2007

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K17/22
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A Power-On-Reset (POR) Circuit compares a logic supply voltage to a reference voltage and provides a logic voltage validity signal if the logic voltage is greater than the reference voltage; the circuit delays, on startup, the validity signal for a selected period and then provides a drive signal for driving a solid-state switch which provides an open circuit on the presence of the drive signal, indicating logic voltage validity, and a short circuit in its absence, indicating invalidity; and the circuit immediately disables the drive signal if the logic voltage falls below the reference voltage. The selected start-up delay period is independent of the supply voltage magnitude.

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