Memory device and method of operating the same

• US 7,457,181 B2
• Filed: 11/16/2006
• Issued: 11/25/2008
• Est. Priority Date: 11/17/2005
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Hoon, Kwon, Kee-Won
• Primary Examiner(s): Yoha; Connie C
• Application Number:
  US11/600,552
• Publication Number:
  US 20070109892A1
• Time in Patent Office: 740 Days
• Field of Search: 365/208, 365/185.25, 365/203, 365/230.06
• US Class Current: 365/208
• CPC Class Codes: G11C 11/4091 Sense or sense/refresh amplifiers, or associated sense circuitry, e.g. for coupled bit-line precharging, equalising or isolating
• CPC Class Codes: G11C 11/4096 Input/output [I/O] data management or control circuits, e.g. reading or writing circuits, I/O drivers or bit-line switches
• CPC Class Codes: G11C 2207/002 Isolation gates, i.e. gates coupling bit lines to the sense amplifier
• CPC Class Codes: G11C 2207/065 Sense amplifier drivers
• CPC Class Codes: G11C 7/065 Differential amplifiers of latching type
• CPC Class Codes: G11C 7/1048 Data bus control circuits, e.g. precharging, presetting, equalising
• CPC Class Codes: G11C 7/1051 Data output circuits, e.g. read-out amplifiers, data output buffers, data output registers, data output level conversion circuits
• CPC Class Codes: G11C 7/106 Data output latches

Abstract

A memory device has a global input/output line pair configured for data transfer. The memory device includes a sense amplifier, a detecting unit and a detect control signal generating unit. The sense amplifier is coupled to the global input/output line pair. The detecting unit detects a potential difference between the global input/output line pair. The detect control signal generating unit disables an operation of the sense amplifier and precharges the global input/output line pair to a predetermined voltage. A precharge operation of a memory device may be performed at a higher speed so that a high speed operation of the memory device may be achieved. In addition, the operating time of the sense amplifier may be decreased so that the power consumption of the memory device may be reduced.

Claims

1. A memory device having a memory cell, a local input/output line pair and a global input/output line pair configured for data transfer, the memory device comprising:

a sense amplifier configured to detect and amplify a potential difference between the global input/output line pair;

a detecting unit configured to generate a detect signal based on a detection of the potential difference between the global input/output line pair;

a precharge circuit configured to precharge the global input/output line pair to a predetermined voltage level; and

a detect control signal generating unit configured to generate a detection sense amplifier control signal for disabling the sense amplifier and a detection precharge control signal, separate and distinct from the detection sense amplifier control signal, for enabling the precharge circuit in response to the detect signal.

2. The memory device of claim 1, wherein the potential difference between the global input/output line pair corresponds to a potential difference between output signals of the sense amplifier.

3. The memory device of claim 1, further comprising a control signal generating unit configured to generate a precharge control signal for controlling the precharge circuit and a sense amplify control signal for controlling the sense amplifier in response to a read command,

wherein the control signal generating unit is coupled to the detect control signal generating unit.

4. The memory device of claim 3, wherein the detect control signal generating unit comprises:

a first SR latch configured to receive the precharge control signal on a set input terminal and the detect signal on a reset input terminal to generate the detection precharge control signal; and

a second SR latch configured to receive the sense amplifier control signal on a set input terminal and the detect signal on a reset input terminal to generate the detection sense amplifier control signal.

5. The memory device of claim 4, wherein the detection precharge control signal is inactivated in response to the detect signal that is activated, thereby enabling the precharge circuit.

6. The memory device of claim 4, wherein the sense amplifier generates an output signal pair respectively having complementary logic levels, and the detecting unit detects the complementary logic levels of the output signal pair of the sense amplifier to activate the detect signal.

7. The memory device of claim 4, wherein the sense amplifier generates an output signal pair, and when all of the output signal pair of the sense amplifier are inactivated, the detect signal transitions to an inactive state after a predetermined time delay.

8. The memory device of claim 3, further comprising:

a first switching circuit configured to couple the local input/output line pair and the global input/output pair,

wherein the control signal generating unit generates a first switching control signal in response to the read command, and

wherein the detect control signal generating unit generates a first detection switching control signal for controlling the first switching circuit based on the first switching control signal and the detect signal.

9. The memory device of claim 8, further comprising,

a second switching circuit configured to couple the local input/output line pair and a bit line pair,

wherein the control signal generating unit generates a second switching control signal for controlling the second switching circuit in response to the read command, and

wherein the detect control signal generating unit generates a second detection switching control signal for controlling the second switching circuit based on the second switching control signal and the detect signal.

10. A memory device comprising:

a local input/output line pair configured to be coupled to a memory cell and a bit line pair through a first switching circuit;

a global input/output line pair configured to be coupled to the local input/output line pair through a second switching circuit;

a precharge circuit configured to precharge the global input/output line pair to a predetermined voltage level;

a sense amplifier configured to detect and amplify a potential difference between the global input/output line pair;

a control signal generating unit configured to generate a first switching control signal, a second switching control signal, a precharge circuit control signal and a sense amplifier control signal in response to a read command; and

a detect control signal generating unit coupled to the control signal generating unit, configured to generate a detection precharge control signal for controlling an operation of the precharge circuit and a detection sense amplifier control signal, separate and distinct from the detection precharge control signal, for controlling an operation of the sense amplifier based on the detected potential difference between the global input/output line pair.

11. The memory device of claim 10, wherein the detect control signal generating unit generates a first detection switching control signal such that the first switching circuit is turned on based on the first switching control signal and such that the first switching circuit is turned off based on the detect signal.

12. The memory device of claim 11, wherein the detect control signal generating unit generates a second detection switching control signal such that the second switching circuit is turned on based on the second switching control signal and such that the second switching circuit is turned off based on the detect signal.

13. The memory device of claim 12, wherein the detect control signal generating unit includes a plurality of SR latches respectively one of which receives a corresponding control signal on a set input terminal and the detect signal on a reset input terminal to generate the detection precharge control signal, the detection sense amplifier control signal and the first and second switching control signals.

14. The memory device of claim 10, wherein the detect signal is activated when output signals of the sense amplifier respectively has complementary voltage levels.

15. The memory device of claim 14, wherein the sense amplifier is disabled and the precharge circuit is enabled after the detect signal is activated.

16. A method of operating a memory device having a memory cell, a local input/output line pair and a global input/output line pair configured for data transfer, the method comprising:

generating a plurality of control signals based on a read command;

enabling a sense amplifier coupled to the global input/output line pair in response to at least one of the control signals;

generating a detect signal based upon detecting a potential difference between the global input/output line pair; and

generating a detection sense amplifier control signal and disabling the sense amplifier in response to the detect signal, and generating a detection precharge control signal, which is separate and distinct from the detection sense amplifier control signal, and precharging the global input/output line pair to a predetermined voltage level in response to the detect signal.

17. The method of claim 16, wherein the potential difference between the global input/output line pair corresponds to a potential difference between output signals of the sense amplifier.

18. The method of claim 16, further comprising,

disconnecting the local input/output line pair from the global input/output line pair in response to the detect signal.

19. The method of claim 18, further comprising,

disconnecting the local input/output line pair from a bit line pair in response to the detect signal.

20. The method of claim 17, further comprising,

inactivating all of the output signals of the sense amplifier in response to the detect signal.

21. A memory device having a memory cell, a local input/output line pair and a global input/output line pair configured for data transfer, the memory device comprising:

a sense amplifier configured to detect and amplify a potential difference between the global input/output line pair;

a detecting unit configured to generate a detect signal based on a detection of the potential difference between the global input/output line pair;

a precharge circuit configured to precharge the global input/output line pair to a predetermined voltage level;

a detect control signal generating unit configured to generate a detection sense amplifier control signal for disabling the sense amplifier and a detection precharge control signal for enabling the precharge circuit in response to the detect signal; and

a control signal generating unit configured to generate a precharge control signal for controlling the precharge circuit and a sense amplify control signal for controlling the sense amplifier in response to a read command,

wherein the control signal generating unit is coupled to the detect control signal generating unit, and

wherein the detect control signal generating unit comprises;

a first SR latch configured to receive the precharge control signal on a set input terminal and the detect signal on a reset input terminal to generate the detection precharge control signal; and

a second SR latch configured to receive the sense amplifier control signal on a set input terminal and the detect signal on a reset input terminal to generate the detection sense amplifier control signal.

22. The memory device of claim 21, wherein the detection precharge control signal is inactivated in response to the detect signal that is activated, thereby enabling the precharge circuit.

23. The memory device of claim 21, wherein the sense amplifier generates an output signal pair respectively having complementary logic levels, and the detecting unit detects the complementary logic levels of the output signal pair of the sense amplifier to activate the detect signal.

24. The memory device of claim 21, wherein the sense amplifier generates an output signal pair, and when all of the output signal pair of the sense amplifier are inactivated, the detect signal transitions to an inactive state after a predetermined time delay.

25. A memory device comprising:

a local input/output line pair configured to be coupled to a memory cell and a bit line pair through a first switching circuit;

a global input/output line pair configured to be coupled to the local input/output line pair through a second switching circuit;

a precharge circuit configured to precharge the global input/output line pair to a predetermined voltage level;

a sense amplifier configured to detect and amplify a potential difference between the global input/output line pair;

a control signal generating unit configured to generate a first switching control signal, a second switching control signal, a precharge circuit control signal and a sense amplifier control signal in response to a read command; and

a detect control signal generating unit coupled to the control signal generating unit, configured to generate a detection precharge control signal for controlling an operation of the precharge circuit and a detection sense amplifier control signal for controlling an operation of the sense amplifier based on the detected potential difference between the global input/output line pair,

wherein the detect control signal generating unit generates a first detection switching control signal such that the first switching circuit is turned on based on the first switching control signal and such that the first switching circuit is turned off based on the detect signal,

wherein the detect control signal generating unit generates a second detection switching control signal such that the second switching circuit is turned on based on the second switching control signal and such that the second switching circuit is turned off based on the detect signal, and

wherein the detect control signal generating unit includes a plurality of SR latches respectively one of which receives a corresponding control signal on a set input terminal and the detect signal on a reset input terminal to generate the detection precharge control signal, the detection sense amplifier control signal and the first and second switching control signals.