04415992 is referenced by 65 patents and cites 3 patents.

A memory system having a plurality of memory cells each capable of storing more than two states also has a reference voltage generator which is used to determine the state stored in a selected memory cell. The plurality of memory cells are arranged in groups of columns, and in a preferred embodiment, the reference voltage generator is arranged in columns which are located between two of the groups of columns. The memory system uses voltage sensing as opposed to current sensing and therefore the only current used is to charge line capacitances. The voltage reference generator is only enabled during the period of time that a cell is being read from.

Title
Memory system having memory cells capable of storing more than two states
Application Number
6/238177
Publication Number
4415992
Application Date
February 25, 1981
Publication Date
November 15, 1983
Inventor
Richard H Adlhoch
Tempe
AZ, US
Agent
Joe E Barbee
Assignee
Motorola
IL, US
IPC
G11C 11/40
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