1. A nonvolatile semiconductor memory device comprising:
a plurality of memory cells which are arranged at the intersections of a plurality of word lines and a plurality of bit lines and each of which includes a variable-resistance element and a diode;
a sense amplifier which compares a voltage corresponding to current in a memory cell selected from said plurality of memory cells with a reference voltage to detect data read from the selected memory cell; and
a controller which generates the reference voltage according to the logical value of a signal output from the sense amplifier and which, before detecting data in the memory cell, adjusts the reference voltage on the basis of current flowing in one of said plurality of bit lines connected to said plurality of memory cells in a half-selected state detected by the sense amplifier.
2. The device according to claim 1, further comprising:
a voltage application module which applies half a read voltage to the word lines and the bit lines when the controller adjusts the reference voltage.
3. The device according to claim 2,
wherein the voltage application module, when reading a memory cell, applies the read voltage to the selected bit line and a voltage lower than half the read voltage to the selected word line.
4. The device according to claim 1,
wherein the reference voltage is set to a third voltage between a first voltage corresponding to data on a high resistance stored in the memory cell and a second voltage corresponding to data on a low resistance.
5. The device according to claim 1,
wherein the controller comprises:
a digital signal generator circuit which generates a digital signal according to the logical value of a signal output from the sense amplifier; and
a digital-to-analog converter which converts a digital signal generated by the digital signal generator circuit into the reference voltage.
6. The device according to claim 5,
wherein the digital signal generator circuit includes a counter which counts up or down the digital signal according to the logical value of a signal output from the sense amplifier.
7. The device according to claim 6,
wherein the controller causes the counter to count down from when the output signal of the sense amplifier has gone to \u201c0\u201d until a certain period of time has elapsed.
8. A nonvolatile semiconductor memory device comprising:
a plurality of memory cells which are arranged at the intersections of a plurality of word lines and a plurality of bit lines and each of which includes a variable-resistance element and a diode;
a sense amplifier which is connected to the selected bit line and which compares a voltage corresponding to current flowing in the selected memory cell with a reference voltage to detect data read from the memory cell; and
a controller which, before reading the memory cell, adjusts the reference voltage according to the logical value of a signal output from the sense amplifier and which adjust the reference voltage in a state where half a read voltage is applied to said plurality of bit lines and said plurality of word lines.
9. The device according to claim 8, further comprising:
a voltage application module which applies half the read voltage to the word lines and the bit lines when the controller adjusts the reference voltage.
10. The device according to claim 9,
wherein the voltage application module, when reading a memory cell, applies the read voltage to the selected bit line and a voltage lower than half the read voltage to the selected word line.
11. The device according to claim 10,
wherein the reference voltage is set to a third voltage between a first voltage corresponding to data on a high resistance stored in the memory cell and a second voltage corresponding to data on a low resistance.
12. The device according to claim 8,
wherein the controller includes a counter which counts up or down according to the logical value of a signal output from the sense amplifier.
13. The device according to claim 12,
wherein the controller causes the counter to count down from when the output signal of the sense amplifier has gone to \u201c0\u201d until a certain period of time has elapsed.
14. A method of reading a nonvolatile semiconductor memory device, the method comprising:
applying half a read voltage to a plurality of bit lines and a plurality of word lines to set a plurality of memory cells in a half-selected state before reading, each of said plurality of memory cells including a variable-resistance element and a diode;
comparing a voltage corresponding to current flowing in a bit line connected to a memory cell in the half-selected state with a reference voltage to generate the reference voltage; and
comparing a voltage corresponding to current flowing in the selected memory cell with the adjusted reference voltage to read the selected memory cell.
15. The method according to claim 14, wherein the adjusted reference voltage is set to a third voltage between a first voltage corresponding to data on a high resistance stored in the memory cell and a second voltage corresponding to data on a low resistance.
16. The method according to claim 14, further comprising:
applying the read voltage to the selected bit line and a voltage lower than half the read voltage to the selected word line when reading a memory cell.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A visualization design system, comprising:
a metadata component to describe characteristics of data;
an analyzer to determine attributes of a peer group, the attributes related to prior visualization design experiences; and
a wizard component to determine a subset of potential visualization types based in part on the characteristics of data and the attributes of the peer group.
2. The system of claim 1, the metadata component provides tags that indicate what type of users or peers have operated on similar types of data (or data sets) in the past, tags that indicate suitable visualization forms or subsets given a respective data type, tags that indicate a relationship between a designer and one or more other members of a peer group, or tags that represent an annotation that describes how a particular visualization was created in the past or how a particular data set was visualized.
3. The system of claim 1, the analyzer includes a data mining component or a learning component.
4. The system of claim 1, the peer group associated with local or remote databases.
5. The system of claim 1, further comprising a profile component to facilitate determining a user’s intent.
6. The system of claim 5, the profile component includes a status field, an organizational chart, a correspondence field, a learning component, a policy component, or a statistical component.
7. The system of claim 1, the wizard component further comprising an attribute processor.
8. The system of claim 1, the wizard component further comprising an intent filter.
9. The system of claim 1, the wizard component further comprising a debugging component.
10. The system of claim 1, the wizard component further comprising a collaborative analyzer.
11. The system of claim 1, the wizard component further comprising a template generator.
12. The system of claim 1, the wizard component further comprising one or more controls to facilitate visualization design.
13. The system of claim 1, the wizard component further comprising a component to determine derivations for visualizations.
14. The system of claim 1, the wizard component further comprising an annotation component to analyze prior visualizations or to allow users to add annotations to a current visualization.
15. The system of claim 1, the wizard component further comprising spreadsheet component that is mined for visualization design information.
16. A visualization design method, comprising:
analyzing peer groups, metadata, or a profile to determine knowledge data relating to a user’s design intentions;
processing the knowledge data to determine a subset of potential visualization options; and
presenting the visualization options to the user in order to select a suitable visualization format given a current data set.
17. The method of claim 16, further comprising analyzing annotations to determine design alternatives.
18. The method of claim 17, further comprising generating help assistance to aid in design of visualizations.
19. The method of claim 16, further comprising analyzing prior visualizations or data sets via data mining or learning components.
20. A visualization design system, comprising:
means for analyzing visualization information associated with one or more peer groups;
means for tagging data that relates to the potential design of a visualization; and
means for generating at least one visualization from a current data set in view of the peer groups or the tagged data.