Patent · US Expired

Fram, fram card, and card system using the same

US5892706A · kind A · utility

38Cited by
6References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 4, 1998
Grant dateApr 6, 1999
Priority date
Expiry dateFeb 4, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C11/22
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Circuitry within a ferroelectric memory prevents inversion of the polarization of ferroelectric memory cells caused by a power on reset signal to avoid corruption of data stored therein. A ferroelectric memory includes a memory cell array, a plurality of word lines commonly connected to the gates of the cell transistors in the same row, a plurality of plate lines commonly connected to the plates of the cell capacitors in the same row, a plurality of bit lines commonly connected to one end of the cell transistors in the same row, and a power on reset circuit for generating a power on reset signal of a predetermined level for a predetermined period of time after the power supply is turned on. An erroneous programming prevention circuit within the memory includes a plurality of switching transistors connected between all of the bit lines and plate lines and a plurality of nodes at a predetermined potential. The switching transistors are controlled by the power on reset signal so that they are on for a predetermined period of time.

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