Patent · US Expired

Device for sensing data in a multi-bit memory cell using a multistep current source

US6069821A · kind A · utility

39Cited by
4References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 26, 1999
Grant dateMay 30, 2000
Priority date
Expiry dateOct 26, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C16/30
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A device and method for sensing data in a multi-bit memory cell of a memory cell array unit is provided where each memory cell has at least two threshold voltage levels. The device can include a multistep current source unit to provide quantized voltages, each having a width smaller than a threshold voltage distribution in a selected memory cell, according to a current flowing through the selected memory cell. An analog-to-digital converter compares the quantized voltages from the multistep current source unit with a plurality of reference voltages to provide a state of the memory cell in binary form. The device and method for sensing data in the multi-bit memory cell uses the quantized voltages to increase sensing reliability, increases sensing speed and increases a gap between the quantized voltages relative to the threshold voltage distribution.

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