Title:
CIRCUIT FOR DETECTING DISTRIBUTION OF CELL THRESHOLD VALUE AND METHOD THEREFOR
Document Type and Number:
Japanese Patent JP3563452
Kind Code:
B2
Abstract:
PURPOSE: To measuring distribution of a threshold value of a transistor through only one time of measurement of an I-V characteristic by connecting a first current node to a second external voltage supplying terminal and connecting a second current node to a third external voltage supplying terminal respectively.
CONSTITUTION: Voltage of a word line WL of a selecting row of a memory cell array 10 is raised up from voltage by which all memory cells M21 are made an OFF state to voltage by which they are turned on, a potential of a bit line is lowered in the order from a bit line BL connected to a cell M21 having a low threshold value to a bit line BL connected to a cell M21 having a high threshold value, voltage comparing circuits connected to each bit line BL are successively inversed, a current of a second pad 12 is decreased, and a current of a third pad 13 is increased. And each voltage distribution of threshold values of plural cells M21 connected to the same word line can be detected by differentiating a current of the pad 12 or the pad 13 by voltage variation of a selecting row word line WL. This, an address of the array 10 may only be selected in the unit of one row.
Inventors:
Toshihiko Himeno
Application Number:
JP18855894A
Publication Date:
September 08, 2004
Filing Date:
August 10, 1994
Export Citation:
Assignee:
Toshiba Corporation
International Classes:
G11C17/00; G11C16/02; G11C29/00; G11C29/12; G11C29/38; G11C29/50; G11C29/56; (IPC1-7): G11C16/02; G11C29/00
Domestic Patent References:
| JP3214497A | ||||
| JP5266700A | ||||
| JP61172300A | ||||
| JP6096600A |
Attorney, Agent or Firm:
Takehiko Suzue