Patent · US Expired

Circuitry for reading phase change memory cells having a clamping circuit

US7570524B2 · kind B2 · utility

30Cited by
3References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 30, 2005
Grant dateAug 4, 2009
Priority date
Expiry dateApr 28, 2026

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C2213/79
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A read circuit for reading at least one memory cell adapted to storing a logic value, the at least one memory cell including: a storage element made of a phase-change material; and an access element for coupling the storage element to the read circuit in response to a selection of the memory cell, the read circuit including: a sense current supply arrangement for supplying a sense current to the at least one memory cell; and at least one sense amplifier for determining the logic value stored in the memory cell on the basis of a voltage developing thereacross, the at least one sense amplifier comprising a voltage limiting circuit for limiting the voltage across the memory cell for preserving the stored logic value, wherein the voltage limiting circuit includes a current sinker for sinking a clamping current, which is subtracted from the sense current and depends on the stored logic value.

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