Non-volatile memory implemented with low-voltages transistors and related system and method

• US 20080018380A1
• Filed: 11/27/2006
• Published: 01/24/2008
• Est. Priority Date: 11/25/2005
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: STMicroelectronics SRL (STMicroelectronics NV)
• Inventors: Sangalli, Miram, Ragone, Giancarlo, Micheloni, Rino, Crippa, Luca, Campardo, Giovanni
• Granted Patent: US 7,499,345 B2
• Time in Patent Office: Days
• US Class Current: 327/536
• CPC Class Codes: H02M 3/07 using capacitors charged and discharged alternately by semiconductor devices with control electrode , e.g. charge pumps

Abstract

An embodiment of an electronic apparatus is provided. The electronic apparatus includes a supplying block for supplying a plurality of operative voltages, one or more operative circuits and a distribution bus for distributing at least part of the operative voltages to each operative circuit. Each operative circuit includes a set of devices for generating a set of output voltages from a set of input ones of the distributed operative voltages. The input and output voltages span an effective range. Each device is capable of sustaining at most a safe voltage between each pair of terminals thereof not higher than the effective range. The devices are controlled by a set of auxiliary ones of the distributed operative voltages spanning an auxiliary range within the effective range, so that a difference between the voltage applied to each pair of terminals thereof is not higher than the safe voltage.

Claims

1. An electronic apparatus including:

a supplying block for supplying a plurality of operative voltages;

at least one operative circuit; and

a distribution bus for distributing at least part of the operative voltages to each operative circuit,

wherein each operative circuit includes a set of devices for generating a set of output voltages from a set of input voltages of the distributed operative voltages, the input and output voltages spanning an effective range, each device being capable of sustaining at most a safe voltage between each pair of terminals thereof not higher than the effective range, and wherein the devices are controlled by a set of auxiliary voltages of the distributed operative voltages spanning an auxiliary range within the effective range so that a difference between the voltages applied to each pair of terminals thereof is not higher than the safe voltage.

2. The electronic apparatus of claim 1, wherein each device is an insulated gate field effect transistor including a drain terminal, a gate terminal and a source terminal.

3. The electronic apparatus of claim 1, wherein the operative voltages are logically ordered in a sequence with increasing values, the difference between each pair of adjacent operative voltages in the sequence being equal to a common pitch value.

4. The electronic apparatus of claim 3, wherein said pitch value is at most equal to a difference between a supply voltage and a reference voltage of the electronic apparatus.

5. The electronic apparatus of claim 1, wherein the operative voltages include a supply voltage and a reference voltage of the electronic apparatus, and wherein the supplying block includes at least one charge pump for generating the other operative voltages from the supply voltage and the reference voltage.

6. The electronic apparatus of claim 5, wherein the at least one operative circuit includes the at least one charge pump, the input voltages of the at least one charge pump including the supplying voltage and the reference voltage, and the output voltages of the at least one charge pump including the other operative voltages.

7. The electronic apparatus of claim 1, wherein the at least one operative circuit includes a voltage regulator for regulating at least part of the operative voltages.

8. The electronic apparatus of claim 1, wherein the at least one operative circuit includes a voltage switch having a first input terminal for receiving a first one of the input voltages, a second input terminal for receiving a second one of the input voltages, an output terminal, and a transfer block for selectively transferring the first input voltage or the second input voltage to the output terminal.

9. The electronic apparatus of claim 1, wherein the electronic apparatus is a non-volatile memory device including an array of memory cells arranged in rows and columns, the non-volatile memory device further including a plurality of word lines each one associated with a corresponding row and a plurality of bit lines each one associated with a corresponding column.

10. The electronic apparatus of claim 9, wherein the at least one operative circuit includes a row selector for selectively applying at least part of the input voltages to a set of selected ones of the word lines.

11. The electronic apparatus of claim 9, wherein the at least one operative circuit includes a column selector for selectively applying at least part of the input voltages to a set of selected ones of the bit lines.

12. The electronic apparatus of claim 9, wherein the electronic apparatus comprising a NAND memory device.

13. The electronic apparatus of claim 9, wherein the electronic apparatus comprises a NOR memory device.

14. The electronic apparatus of claim 1, wherein the electronic apparatus is integrated in a chip of semiconductor material.

15. A method for controlling an electronic apparatus including at least one operative circuit, the method including the steps of:

supplying a plurality of operative voltages;

distributing at least part of the operative voltages to each operative circuit; and

in each operative circuit, generating a set of output voltages from a set of input voltages of the distributed operative voltages by means of a set of devices, the input and output voltages spanning an effective range, each device being capable of sustaining at most a safe voltage between each pair of terminals thereof not higher than the effective range, and controlling the devices with a set of auxiliary voltages of the distributed operative voltages spanning an auxiliary range within the effective range so that a difference between the voltages applied to each pair of terminals thereof is not higher than the safe voltage.

16. A circuit, comprising:

input nodes each operable to receive a respective one of a plurality of input voltages including a lowest voltage, a highest voltage, and at least one intermediate voltage in between the lowest and highest voltages, each difference between respective pairs of sequential ones of the input voltages being no greater than a predetermined safe voltage; and

a set of interconnected electronic devices coupled to the input nodes, each device having a respective pair of device nodes, the set of electronic devices operable such that each voltage across each respective pair of the device nodes is no greater than the predetermined safe voltage.

17. The circuit of claim 16 wherein the input voltages have a same polarity.

18. The circuit of claim 16 wherein the input voltages have different polarities.

19. The circuit of claim 16 wherein the input voltages include multiple intermediate voltages.

20. The circuit of claim 16 wherein the differences between respective pairs of sequential ones of the input voltages are equal to a same value.

21. The circuit of claim 16, further comprising:

a first supply node operable to receive a first supply voltage;

a second supply node operable to receive a second supply voltage; and

wherein the predetermined safe voltage is no greater than a difference between the first and second supply voltages.

22. The circuit of claim 16 wherein at least one of the electronic devices comprises a transistor.

23. A circuit, comprising:

output nodes each operable to provide a respective one of a plurality of output voltages including a lowest voltage, a highest voltage, and at least one intermediate voltage in between the lowest and highest voltages, each difference between respective pairs of sequential ones of the output voltages being no greater than a predetermined safe voltage;

input nodes each coupled to a respective one of the output nodes; and

a set of interconnected electronic devices coupled to the input nodes, each device having a respective pair of device nodes, the set of electronic devices operable such that each voltage across each respective pair of the device nodes is no greater than the predetermined safe voltage.

24. The circuit of claim 23 wherein the number of input nodes is less than the number of output nodes.

25. The circuit of claim 23 wherein the number of input nodes is equal to the number of output nodes.

26. The circuit of claim 23 wherein the set of interconnected electronic devices is coupled to the output nodes and is operable to generate the output voltages.

27. A nonvolatile memory, comprising:

floating-gate memory cells;

insulated-gate transistors coupled to the floating-gate memory cells and each including a respective gate insulator substantially having a thickness; and

no insulated-gate transistor including a gate insulator having other than substantially the thickness.

28. The nonvolatile memory of claim 27 wherein the insulated-gate transistors each comprise a respective MOS-type transistor.

29. The nonvolatile memory of claim 27, further comprising:

a first supply node operable to receive a first supply voltage;

a second supply node operable to receive a second supply voltage; and

wherein each of the insulated-gate transistors has a gate-insulator breakdown voltage that is substantially equal to or greater than a difference between the first and second supply voltages.

30. An integrated circuit, comprising:

a first circuit comprising a plurality of output nodes and operable to respectively generate on the output nodes a plurality of output voltages including a lowest voltage, a highest voltage, and at least one intermediate voltage in between the lowest and highest voltages, each difference between respective pairs of sequential ones of the output voltages being no greater than a predetermined safe voltage; and

a second circuit having first input nodes coupled to receive the output voltages from the first integrated circuit, the second integrated circuit comprising a first set of interconnected electronic devices coupled to the first input nodes, each device having a respective pair of device nodes, the set of electronic devices operable such that each voltage across each respective pair of the device nodes is no greater than the predetermined safe voltage.

31. The integrated circuit of claim 30 wherein the first circuit further comprises:

second input nodes each coupled to a respective one of the output nodes; and

a second set of interconnected electronic devices coupled to the second input nodes, each device having a respective pair of device nodes, the second set of electronic devices operable such that each voltage across each respective pair of the device nodes is no greater than the predetermined safe voltage.

32. The integrated circuit of claim 30 wherein the number of second input nodes is less than the number of output nodes.

33. The integrated circuit of claim 30 wherein the number of second input nodes is equal to the number of output nodes.

34. The integrated circuit of claim 30 wherein the second set of interconnected electronic devices is coupled to the output nodes and is operable to generate the output voltages.

35. An electronic system, comprising:

a controller; and

an integrated circuit coupled to the controller and comprising,

a first circuit comprising a plurality of output nodes and operable to respectively generate on the output nodes a plurality of output voltages including a lowest voltage, a highest voltage, and at least one intermediate voltage in between the lowest and highest voltages, each difference between respective pairs of sequential ones of the output voltages being no greater than a predetermined safe voltage, and

a second circuit having first input nodes coupled to receive the output voltages from the first integrated circuit, the second integrated circuit comprising a first set of interconnected electronic devices coupled to the first input nodes, each device having a respective pair of device nodes, the set of electronic devices operable such that each voltage across each respective pair of the device nodes is no greater than the predetermined safe voltage.

36. The electronic system of claim 35 wherein the integrated circuit comprises a nonvolatile memory.

37. A method, comprising:

receiving a plurality of input voltages including a lowest voltage, a highest voltage, and at least one intermediate voltage in between the lowest and highest voltages, each difference between respective pairs of sequential ones of the input voltages being no greater than a predetermined safe voltage; and

operating a set of interconnected electronic devices each having a respective pair of device nodes such that each voltage across each respective pair of the device nodes is no greater than the predetermined safe voltage.

38. The method of claim 37 wherein operating the set of interconnected electronic devices comprises generating the input voltages with the set of electronic devices.

39. The method of claim 37 wherein operating the set of interconnected electronic devices comprises generating the input voltages and at least one other voltage, each difference between respective pairs of sequential ones of the input and other voltages being no greater than the predetermined safe voltage.