Patent · US Expired

Programmable read only memory with output indicating programming state

US5392418A · kind A · utility

0Cited by
7References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 14, 1992
Grant dateFeb 21, 1995
Priority date
Expiry dateFeb 14, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C17/18
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A non-volatile memory cell including a pn diode and a circuit for sensing the logic state of the pn diode such that a logic one state indicates that the diode is in its normal state, while the other logic state is created by fusing the diode for creating a short circuit. The circuit for sensing the logic state of the diode includes a circuit for developing a sense voltage across the diode, a first comparator for comparing the sense voltage with a first reference voltage greater than the normal junction voltage, a second comparator for comparing the sense voltage with a second reference voltage less than the normal junction voltage but greater than the fused junction voltage and a circuit responsive to the outputs of the first and second comparators to provide an output signal which has a first value if the sense voltage is between the first and second reference voltages and a second value if the sense voltage is not between the first and second reference voltages.

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