阅读说明：本技术 半导体存储器设备和半导体存储器设备的操作方法 (Semiconductor memory device and method of operating semiconductor memory device ) 是由 崔训对 金和平 于 2019-07-16 设计创作，主要内容包括：本发明构思涉及一种半导体存储器设备。该半导体存储器设备可以包括：第一缓冲器,被配置为接收第一信号；第二缓冲器,被配置为接收第二信号；检测器,被配置为将由第一缓冲器接收的第一信号的第一相位与由第二缓冲器接收的第二信号的第二相位进行比较并生成检测信号；以及校正器,响应于检测信号被激活或去激活。当校正器响应于检测信号被激活时,校正器可以被配置为校正由第一缓冲器接收的第一信号和由第二缓冲器接收的第二信号。(The present inventive concept relates to a semiconductor memory device. The semiconductor memory device may include: a first buffer configured to receive a first signal; a second buffer configured to receive a second signal; a detector configured to compare a first phase of a first signal received by the first buffer with a second phase of a second signal received by the second buffer and generate a detection signal; and a corrector activated or deactivated in response to the detection signal. When the corrector is activated in response to the detection signal, the corrector may be configured to correct the first signal received by the first buffer and the second signal received by the second buffer.)

1. A semiconductor memory device, comprising:

a memory cell array including memory cells;

an address buffer configured to receive address information on the memory unit from an external device;

a command buffer configured to receive a command for accessing the memory unit from an external device;

a first strobe buffer configured to receive a first signal and a second signal from an external device; and

a first data buffer configured to receive data from an external device in synchronization with the first signal and the second signal,

wherein the first strobe buffer comprises:

a first buffer configured to receive a first signal,

a second buffer configured to receive a second signal,

a detector configured to compare a first phase of the first signal received by the first buffer with a second phase of the second signal received by the second buffer and generate a detection signal, an

A corrector configured to be activated or deactivated in response to the detection signal, and correct the first signal received by the first buffer and the second signal received by the second buffer when activated in response to the detection signal.

2. The semiconductor memory device according to claim 1, wherein the corrector is activated in response to a first phase of the first signal and a second phase of the second signal being different from each other.

3. The semiconductor memory device of claim 1, wherein the corrector is deactivated in response to the first phase of the first signal being the same as the second phase of the second signal.

4. The semiconductor memory device according to claim 1, wherein the detector comprises:

a first logic operator configured to deactivate the corrector in response to both the first phase and the second phase being in a logic high state; and

a second logic operator configured to deactivate the corrector in response to both the first phase and the second phase being in a logic low state.

5. The semiconductor memory device of claim 1, wherein the detector is configured to detect a first phase of the first signal at a first node in the first buffer and a second phase of the second signal at a second node in the second buffer, and

the corrector is configured to: (i) correcting the first phase of the first signal at a third node, the third node being in the first buffer and distinct from the first node; and (ii) correcting the second phase of the second signal at a fourth node, the fourth node being in the second buffer and different from the second node.

6. The semiconductor memory device according to claim 5, wherein the first buffer includes at least one inverter between the first node and the third node, and the second buffer includes at least another inverter between the second node and the fourth node.

7. The semiconductor memory device according to claim 5, wherein the corrector comprises:

a first inverter having a first input connected to the third node in the first buffer and a first output connected to the fourth node in the second buffer; and

a second inverter having a second input connected to the fourth node in the second buffer and a second output connected to the third node in the first buffer.

8. The semiconductor memory device according to claim 5, further comprising:

another corrector connected to the fifth node in the first buffer and the sixth node in the second buffer, the another corrector configured to correct the first signal and the second signal.

9. The semiconductor memory device according to claim 1, further comprising:

a second strobe buffer configured to output the third signal and the fourth signal to an external device; and

a second data buffer configured to output second data to the external device in synchronization with the third signal and the fourth signal.

10. The semiconductor memory device according to claim 1, further comprising:

control logic circuitry configured to activate the first data buffer, the first buffer, and the second buffer in response to the command being a write command.

11. The semiconductor memory device of claim 10, wherein the control logic circuit is further configured to deactivate the first data buffer, the first buffer, the second buffer, and the detector in response to the command not being a write command.

12. The semiconductor memory device according to claim 1, further comprising:

a row decoder configured to select some memory cells from the memory cell array in response to address information; and

a write driver/sense amplifier configured to perform a write or read operation on the memory cell selected by the row decoder.

13. A semiconductor memory device, comprising:

a memory cell array including memory cells;

an address buffer configured to receive address information on the memory unit from an external device;

a command buffer configured to receive a command for accessing the memory unit from an external device;

a control logic circuit configured to activate a first signal in response to receiving a write command for the memory cell array from an external device;

a first gate buffer configured to receive a first gate signal and a second gate signal from an external device, compare a first phase of the first gate signal with a second phase of the second gate signal in response to the first signal being activated, correct the first gate signal and the second gate signal in response to the first phase and the second phase being different from each other, and output the corrected first gate signal and the second gate signal as a third gate signal and a fourth gate signal;

a first data buffer configured to latch a first data signal received from an external device in synchronization with a third strobe signal and a fourth strobe signal in response to a first signal being activated;

a second strobe buffer configured to output a third signal and a fourth signal to an external device in response to receiving a read command for the memory cell array from the external device; and

a second data buffer configured to output the second data signal to the external device in synchronization with the third signal and the fourth signal.

14. The semiconductor memory device according to claim 13, wherein the control logic circuit is further configured to deactivate the first signal in response to receiving another command different from the write command from the external device.

15. The semiconductor memory device of claim 13, wherein the first strobe buffer is further configured to block a current for correcting the first strobe signal and the second strobe signal in response to the first signal being deactivated.

16. The semiconductor memory device of claim 13, wherein the first strobe buffer is further configured to block current for correcting the first strobe signal and the second strobe signal in response to the first signal being activated and the first phase being the same as the second phase.

17. The semiconductor memory device of claim 13, wherein the first strobe buffer comprises:

a first operator configured to output a result of a nor logic between the first strobe signal and the second strobe signal as a first intermediate signal;

a second operator configured to output a result of the nand logic between the first strobe signal and the second strobe signal as a second intermediate signal;

a third operator configured to output a result of the nand logic between the inverted signal of the first intermediate signal and the second intermediate signal as a third intermediate signal; and

a fourth operator configured to output a result of NOR logic between the third intermediate signal and the first signal as the second signal,

the first signal is a low level activation signal, and

the first strobe buffer is configured to activate correction of the first strobe signal and the second strobe signal in response to the second signal being high.

18. The semiconductor memory device of claim 13, wherein the control logic circuit is further configured to activate or deactivate a second signal,

the first strobe buffer is configured to correct the first strobe signal and the second strobe signal depending on the first signal, the first phase and the second phase in response to the second signal being activated, an

The first strobe buffer is further configured to correct the first strobe signal and the second strobe signal independently of the first phase and the second phase using the first signal in response to the second signal being activated.

19. A method of operating a semiconductor memory device, comprising:

receiving a write command at a command buffer of a semiconductor memory device;

receiving address information associated with a write command at an address buffer of a semiconductor memory device;

receiving a first strobe signal and a second strobe signal;

correcting the first strobe signal and the second strobe signal in response to a first phase of the first strobe signal being different from a second phase of the second strobe signal after receiving the write command;

receiving data at a data buffer of the semiconductor memory device in synchronization with the first strobe signal and the second strobe signal; and

the received data is written in the memory cells of the semiconductor memory device corresponding to the address information.

20. The method of claim 19, further comprising:

stopping correction of the first and second strobe signals in response to the first phase being the same as the second phase after receiving the write command; and

in response to receiving another command different from the write command, the correction of the first strobe signal and the second strobe signal is stopped regardless of whether the first phase is different from the second phase.

Technical Field

The present inventive concept relates to a semiconductor circuit, and in particular, to a semiconductor memory device configured to correct a strobe signal (strobe), and/or a method of operating the same.

Background

A semiconductor device (e.g., a semiconductor memory device) is configured to perform data communication with an external device. The semiconductor memory device may store data received from an external device and may transmit the stored data to the external device. A strobe signal (e.g., a data strobe signal) may be used for data communication between a semiconductor device (e.g., a semiconductor memory device) and an external device.

When data is transferred from an external device to the semiconductor memory device, the data strobe signal may be transferred to the semiconductor memory device together with the data. The data strobe signal may transition between a high logic level and a low logic level, and the transition of the data strobe signal may be used to inform the semiconductor memory device of the timing of latching each bit of data.

When data is transferred from the semiconductor memory device to an external device, the data strobe signal may be transferred to the external device together with the data. The data strobe signal may transition between a high logic level and a low logic level, and the transition of the data strobe signal may be used to inform an external device of the timing at which each bit of data is latched.

As the transmission speed of data increases, a data strobe signal is applied to a variety of semiconductor devices or semiconductor memory devices, for example, to improve the accuracy of data transmission. In order to further improve the accuracy of data transmission, many studies have been made to improve the transmission accuracy of the data strobe signal. In addition, methods for reducing power consumed to improve transmission accuracy of the data strobe signal are being studied.

Disclosure of Invention

Some example embodiments of the inventive concepts provide a semiconductor memory device configured to correct a data strobe signal at a reduced power, thereby improving accuracy of data transmission at the reduced power, and a method of operating the semiconductor memory device.

According to some example embodiments of the inventive concepts, a semiconductor memory device may include: a memory cell array including memory cells; an address buffer configured to receive address information on the memory unit from an external device; a command buffer configured to receive a command for accessing the memory unit from an external device; a first strobe buffer configured to receive a first signal and a second signal from an external device; and a first data buffer configured to receive data from the external device in synchronization with the first signal and the second signal. The strobe buffer includes: a first buffer configured to receive a first signal; a second buffer configured to receive a second signal; a detector configured to compare a first phase of the first signal received by the first buffer with a second phase of the second signal received by the second buffer and generate a detection signal; and a corrector configured to be activated or deactivated in response to the detection signal, and correct the first signal received by the first buffer and the second signal received by the second buffer when activated in response to the detection signal.

According to some example embodiments of the inventive concepts, a semiconductor memory device may include: a memory cell array including memory cells; an address buffer configured to receive address information on the memory unit from an external device; a command buffer configured to receive a command for accessing the memory unit from an external device; a control logic circuit configured to activate a first signal in response to receiving a write command for the memory cell array from an external device; a first gate buffer configured to receive the first gate signal and the second gate signal from the external device, compare a first phase of the first gate signal with a second phase of the second gate signal in response to the first signal being activated, correct the first gate signal and the second gate signal in response to the first phase and the second phase being different from each other, and output the corrected first gate signal and the second gate signal as a third gate signal and a fourth gate signal. The memory device further includes: a first data buffer configured to latch a first data signal received from an external device in synchronization with a third strobe signal and a fourth strobe signal in response to a first signal being activated; a second strobe buffer configured to output a third signal and a fourth signal to an external device in response to receiving a read command for the memory cell array from the external device; and a second data buffer configured to output the second data signal to the external device in synchronization with the third signal and the fourth signal.

According to some example embodiments of the inventive concepts, a method of operating a semiconductor memory device may include: receiving a write command at a command buffer of a semiconductor memory device; receiving address information associated with a write command at an address buffer of a semiconductor memory device; receiving a first strobe signal and a second strobe signal; correcting the first strobe signal and the second strobe signal in response to a first phase of the first strobe signal being different from a second phase of the second strobe signal after receiving the write command; receiving data at a data buffer of the semiconductor memory device in synchronization with the first strobe signal and the second strobe signal; and writing the received data in a memory cell of the semiconductor memory device corresponding to the address information.

Drawings

Example embodiments will be more clearly understood from the following brief description taken in conjunction with the accompanying drawings. The drawings represent non-limiting example embodiments as described herein.

Fig. 1 is a block diagram illustrating a semiconductor memory device according to some example embodiments of the inventive concepts.

Fig. 2 is a flowchart illustrating a method of operating a semiconductor memory apparatus according to some example embodiments of the inventive concepts.

Fig. 3 is a block diagram illustrating a first strobe buffer according to some example embodiments of the inventive concepts.

Fig. 4 illustrates a detector according to some example embodiments of the inventive concept.

Fig. 5 shows a first example of the operation of the detector of fig. 4.

Fig. 6 shows a second example of the operation of the detector of fig. 4.

Fig. 7 shows a third example of the operation of the detector of fig. 4.

Fig. 8 shows a fourth example of the operation of the detector of fig. 4.

Fig. 9 illustrates a detector according to some example embodiments of the inventive concepts.

Fig. 10 illustrates a corrector according to some example embodiments of the inventive concept.

Fig. 11 illustrates a first strobe buffer according to some example embodiments of the inventive concepts.

It should be noted that these drawings are intended to illustrate the general features of methods, structures and/or materials used in certain example embodiments, and to supplement the written description provided below. However, the drawings are not to scale and may not accurately reflect the precise structural or performance characteristics of any given embodiment, and should not be construed as limiting or restricting the scope of values or properties encompassed by example embodiments. For example, the relative thicknesses and positioning of particles, layers, regions and/or structural elements may be reduced or exaggerated for clarity. The use of similar or identical reference numbers in the various figures is intended to indicate the presence of similar or identical elements or features.

Detailed Description

Example embodiments of the present inventive concept will now be described more fully with reference to the accompanying drawings, in which example embodiments are shown.

Fig. 1 is a block diagram illustrating a semiconductor memory device 10 according to some example embodiments of the inventive concepts. Referring to fig. 1, a semiconductor memory device 10 may include a memory cell array 11, a row decoder 12, a write driver/sense amplifier 13, a control logic circuit 14, an address buffer 15, a command buffer 16, a first gate buffer 17, a first data buffer 18, a second gate buffer 19, and/or a second data buffer 20.

The memory cell array 11 may include a plurality of memory cells. The memory cells may include various memory cells such as Dynamic Random Access Memory (DRAM) cells, Static Random Access Memory (SRAM) cells, phase change memory cells, magnetic memory cells, resistive memory cells, and/or FLASH memory (FLASH) memory cells. The memory cells may be connected to the row decoder 12 through word lines WL and may be connected to write drivers/sense amplifiers 13 through bit lines BL.

The row decoder 12 may receive a row address RA from an address buffer 15. The row decoder 12 may decode the row address RA and may select the word line WL based on the result of the decoding. The row decoder 12 may apply a first voltage to selected ones of the word lines WL, and may apply a second voltage different from the first voltage to unselected word lines.

The write driver/sense amplifier 13 may receive a column address CA from the address buffer 15. The write driver/sense amplifier 13 may decode the column address CA, and may select the bit line BL based on the result of the decoding. The write driver/sense amplifier 13 may apply a third voltage to selected ones of the bit lines BL, and may apply a fourth voltage different from the third voltage to unselected bit lines. Although fig. 1 shows the write driver/sense amplifier 13 as one circuit, the inventive concept is not so limited. For example, the write driver/sense amplifier 13 may be included in one circuit, or may be a separate circuit, e.g., the write driver is separate from the sense amplifier.

Control logic circuit 14 may receive commands CMD from command buffer 16. The control logic circuit 14 may control the row decoder 12 and the write driver/sense amplifier 13 according to the command CMD. For example, the control logic circuit 14 may control the row decoder 12 and the write driver/sense amplifier 13 to perform a write operation or a read operation on a selected memory cell of the memory cells of the memory cell array 11. The control logic circuit 14 may control the row decoder 12 and the write driver/sense amplifier 13 to perform an erase operation on the selected memory cell.

The control logic circuit 14 may control the first signal/EN 1 and the second signal/EN 2. For example, when the command CMD is a write command, the control logic circuit 14 may activate (activate) the first signal/EN 1 (e.g., the signal may be set to a low level, such as a low logic value with a low voltage). When the command CMD is another command (i.e., not a write command), the control logic circuit 14 may deactivate (activate) the first signal/EN 1 (e.g., may set the signal to a high level, such as a high logic value having a high voltage greater than a low voltage).

When the command CMD is a read command, the control logic circuit 14 may activate the second signal/EN 2 (e.g., the signal may be set to a low level). When command CMD is another command (i.e., not a read command), control logic circuit 14 may deactivate second signal/EN 2 (e.g., may set the signal to a high level).

The control logic circuit 14 may control the detection control signal DET _ ON. For example, when the correction operations ON the first and second data strobe signals DQS1 and DQS2 are activated, the control logic circuit 14 may activate the detection control signal DET _ ON (e.g., to a high level). When the correction operation is deactivated, the control logic circuit 14 may deactivate the detection control signal DET _ ON (e.g., to a low level).

The control logic circuit 14 can control the detection control signal DET _ ON at various timings. For example, when power is supplied to the semiconductor memory device 10, a decision may be made whether to activate the correction operation. When power is supplied, a decision whether to activate the correction operation may be made based on the setting of a mode register (not shown). The mode register may be included as part of the semiconductor memory device 10, or alternatively may not be part of the semiconductor device 10, and may be external to the semiconductor device 10. While maintaining the power supply, the semiconductor memory device 10 may maintain the detection control signal DET _ ON in an activated or deactivated state (active or inactive state).

As another example, the control logic circuit 14 may activate the detection control signal DET _ ON when a write operation is performed. For example, the detection control signal DET _ ON may have an activation period (activationperiod) similar to the first signal/EN 1. The detection control signal DET _ ON may be activated in response to receiving the write command as a command CMD or in response to the first signal/EN 1 being activated. The detection control signal DET _ ON may be deactivated in response to receiving other commands than the write command as the command CMD or in response to the first signal/EN 1 being deactivated.

The address buffer 15 may receive an address ADDR from an external device (e.g., a controller of the semiconductor memory device 10). The address buffer 15 may transfer a row address RA of the received address ADDR to the row decoder 12, and may transfer a column address CA to the write driver/sense amplifier 13. The command buffer 16 may transfer a command CMD received from an external device (e.g., a controller) to the control logic circuit 14.

The first strobe buffer 17 may receive the first data strobe signal DQS1 and the second data strobe signal DQS2 from an external device (e.g., a controller). For example, after receiving a write command as the command CMD, each of the first and second data strobe signals DQS1 and DQS2 may be toggled between a high level and a low level (toggle). The first data strobe signal DQS1 and the second data strobe signal DQS2 may be complementary signals, such as signals that are "180 degrees out of phase" with respect to each other.

The first strobe buffer 17 may rearrange the switching timings of the first and second data strobe signals DQS1 and DQS2, and may output the rearranged signals as the third and fourth data strobe signals DQS3 and DQS 4. The first strobe buffer 17 may include a detector 130 and a corrector 140.

The detector 130 may operate during a write operation (e.g., when the first signal/EN 1 is activated) and when the detection control signal DET _ ON is activated. The detector 130 may compare the phase of the first data strobe signal DQS1 with the phase of the second data strobe signal DQS 2.

When the phase of the first data strobe signal DQS1 is the same as the phase of the second data strobe signal DQS2 (e.g., the first data strobe signal DQS1 and the second data strobe signal DQS2 do not toggle), the detector 130 may deactivate the corrector 140. The detector 130 may activate the corrector 140 when the phase of the first data strobe signal DQS1 is different from the phase of the second data strobe signal DQS2 (e.g., the first data strobe signal DQS1 and the second data strobe signal DQS2 toggle).

The corrector 140 may correct the first data strobe signal DQS1 and the second data strobe signal DQS 2. For example, when the duty ratio of one of the first data strobe signal DQS1 and the second data strobe signal DQS2 is changed, the corrector 140 may restore the changed duty ratio to the original value.

If the switching timings of the first and second data strobe signals DQS1 and DQS2 are not consistent with each other, skew may occur, and in this case, the corrector 140 may reduce the difference in switching timing between the first and second data strobe signals DQS1 and DQS 2. The corrector 140 may output the corrected signals as the third data strobe signal DQS3 and the fourth data strobe signal DQS 4.

In some example embodiments, the first strobe buffer 17 may perform the correction operation only when the first and second data strobe signals DQS1 and DQS2 toggle, and may stop the correction operation when the first and second data strobe signals DQS1 and DQS2 do not toggle. When the correction operation is stopped, the current flowing in the corrector 140 may be reduced, for example, blocked (block). Therefore, the power consumption of the semiconductor memory device 10 can be reduced.

When the first signal/EN 1 is activated, the first data buffer 18 may be activated. The first data buffer 18 may receive the third data strobe signal DQS3 and the fourth data strobe signal DQS4 from the first strobe buffer 17. The first data buffer 18 may latch the first data signal DQ1 received from an external device (e.g., a controller) in synchronization with the third data strobe signal DQS3 and the fourth data strobe signal DQS 4.

For example, the first data buffer 18 may store the level of the first data signal DQ1 at the timing at which the third data strobe signal DQS3 and the fourth data strobe signal DQS4 toggle. The first data buffer 18 may deserialize (deserialize) the level DQ1L of the stored first data signal DQ1, and may transfer the deserialized result to the write driver/sense amplifier 13.

When the second signal/EN 2 is activated, the second strobe buffer 19 may be activated. The second strobe buffer 19 may output the fifth data strobe signal DQS5 and the sixth data strobe signal DQS6 to an external device (e.g., a controller). For example, the second strobe buffer 19 may receive a clock signal from an external device and may generate the fifth data strobe signal DQS5 and the sixth data strobe signal DQS6 from the clock signal.

When the second signal/EN 2 is activated, the second data buffer 20 may be activated. The second data buffer 20 may receive a level DQ2L of a second data signal DQ2 from the write driver/sense amplifier 13. The second data buffer 20 may serialize (serialize) the level of the second data signal DQ2 and output the second data signal DQ2 in synchronization with the fifth data strobe signal DQs5 and the sixth data strobe signal DQs 6.

For example, the first data strobe signal DQS1 and the fifth data strobe signal DQS5 may communicate with an external device (e.g., a controller) through the same signal line. The second data strobe signal DQS2 and the sixth data strobe signal DQS6 may communicate with an external device (e.g., a controller) through the same signal line. The first data signal DQ1 and the second data signal DQ2 may communicate with an external device (e.g., a controller) through the same signal line.

Fig. 2 is a flowchart illustrating a method of operating the semiconductor memory apparatus 10 according to some example embodiments of the inventive concepts. Referring to fig. 1 and 2, in step S110, the detector 130 may detect a difference of the first data strobe signal DQS1 and the second data strobe signal DQS 2.

Upon detecting a difference between the first data strobe signal DQS1 and the second data strobe signal DQS2, the detector 130 may activate the corrector 140 to activate the correction of the first data strobe signal DQS1 and the second data strobe signal DQS2 in step S120.

In step S130, the detector 130 may detect that the first data strobe signal DQS1 and the second data strobe signal DQS2 are unified (uniform) to the same level, e.g., the same voltage level and/or the same logic level. Upon detecting unification (unification) of the first data strobe signal DQS1 and the second data strobe signal DQS2, the detector 130 may deactivate correction of the first data strobe signal DQS1 and the second data strobe signal DQS2 in step S140.

Fig. 3 is a block diagram illustrating a first strobe buffer 100 according to some example embodiments of the inventive concepts. The first strobe buffer 100 of fig. 3 shows the internal structure of the first strobe buffer 17 shown in fig. 1 in more detail.

Referring to fig. 1 and 3, the first strobe buffer 100 may include a first buffer 110, a second buffer 120, a detector 130, and a corrector 140. The first and second buffers 110 and 120 may be activated or deactivated in response to the first signal/EN 1. The first buffer 110 may generate the third data strobe signal DQS3 from the first data strobe signal DQS1 and the second data strobe signal DQS 2. The first buffer 110 may include a first comparator 111 and first inverters 112 to 117.

The first comparator 111 may have a first positive input to which the first data strobe signal DQS1 is transferred and a second negative input to which the second data strobe signal DQS2 is transferred. The output of the first comparator 111 may be transmitted through the first inverters 112 to 117 connected in series. The number of first inverters included in the first buffer 110 may not be limited. The number of first inverters included in the first buffer 110 may be an even number. In the case where the length of the transmission path of the third data strobe signal DQS3 is increased, the number of first inverters may be increased.

The output of a specific one (e.g., 117) of the first inverters 112 to 117 is shown as the third data strobe signal DQS3, but the output of any one of the first inverters placed after the corrector 140 may be used as the third data strobe signal DQS 3. The first inverters 112 to 117 may serve as a repeater (repeater) that transmits the third data strobe signal DQS 3.

The second buffer 120 may generate the fourth data strobe signal DQS4 from the first data strobe signal DQS1 and the second data strobe signal DQS 2. The second buffer 120 may include a second comparator 121 and second inverters 122 to 127.

The second comparator 121 may have a first negative input to which the first data strobe signal DQS1 is transferred and a second positive input to which the second data strobe signal DQS2 is transferred. The output of the second comparator 121 may be transmitted through the second inverters 122 to 127. The number of second inverters included in the second buffer 120 may not be limited. The number of the second inverters included in the second buffer 120 may be an even number; however, the inventive concept is not limited thereto. In the case where the length of the transmission path of the fourth data strobe signal DQS4 is increased, the number of second inverters may be increased.

The output of a specific one (e.g., 127) of the second inverters 122 to 127 is shown as the fourth data strobe signal DQS4, but the output of any one of the second inverters placed after the corrector 140 may be used as the fourth data strobe signal DQS 4. The second inverters 122 to 127 may serve as relays for transmitting the fourth data strobe signal DQS 4.

The detector 130 may receive the first intermediate signal SI1 output from the first inverter 113 and the second intermediate signal SI2 output from the second inverter 123. The detector 130 may also receive the first signal/EN 1 and the detection control signal DET _ ON. Depending ON the first signal/EN 1, the detection control signal DET _ ON, the first intermediate signal SI1 and the second intermediate signal SI2, the detector 130 may activate or deactivate the third signal EN 3.

For example, the detector 130 may activate the third signal EN3 (e.g., to a high level) only when the first signal/EN 1 is in an active state (e.g., a logic low level), the detection control signal DET _ ON is in an active state (e.g., a logic high level), and the phase of the first intermediate signal SI1 is different from the phase of the second intermediate signal SI 2.

When the first signal/EN 1 is in a deactivated state (e.g., high level), the detection control signal DET _ ON is in a deactivated state (e.g., low level), or the phase of the first intermediate signal SI1 is the same as the phase of the second intermediate signal SI2, the detector 130 may deactivate the third signal EN3 (e.g., to low level).

As shown in fig. 3, the detector 130 may obtain an output of the first inverter 113 as a first intermediate signal SI1, and may obtain an output of the second inverter 123 as a second intermediate signal SI 2. However, in some example embodiments, the detector 130 may obtain the output of any one of the first inverters 112 to 117 or the output of the first comparator 111 as the first intermediate signal SI 1. In addition, the detector 130 may obtain the output of any one of the second inverters 122 to 127 or the output of the second comparator 121 as the second intermediate signal SI 2.

The corrector 140 may receive the output of the first inverter 115 as the third intermediate signal SI3 and may receive the output of the second inverter 125 as the fourth intermediate signal SI 4. The corrector 140 may also receive a third signal EN 3. When the third signal EN3 is activated (e.g., to a high level), the corrector 140 may correct the third and fourth intermediate signals SI3 and SI4 using the third and fourth intermediate signals SI3 and SI 4.

For example, the corrector 140 may correct the duty ratios of the third and fourth intermediate signals SI3 and SI4 to target values (e.g., 50%). In addition, the corrector 140 may rearrange the switching timings of the third intermediate signal SI3 and the fourth intermediate signal SI4 to eliminate or reduce skew.

As shown in fig. 3, the corrector 140 may obtain the output of the first inverter 115 as the third intermediate signal SI3, and may obtain the output of the second inverter 125 as the fourth intermediate signal SI 4. However, in some example embodiments, the corrector 140 may obtain the output of any one of the first inverters 112 to 117 or the output of the first comparator 111 as the third intermediate signal SI 3. Further, the corrector 140 may obtain the output of any one of the second inverters 122 to 127 or the output of the second comparator 121 as the fourth intermediate signal SI 4.

Fig. 4 illustrates a detector 130 according to some example embodiments of the inventive concepts. Referring to fig. 3 and 4, the detector 130 may include first to eighth logic gates, for example, first to eighth operators 131 to 138. The first operator 131 may perform a NOR-logic (e.g., NOR) operation on the first intermediate signal SI1 and the second intermediate signal SI 2.

The second operator 132 may perform an operation ON the output of the first operator 131 and the detection control signal DET _ ON. When the detection control signal DET _ ON is activated (e.g., to a high level), the second operator 132 may invert and output the output of the first operator 131. When the detection control signal DET _ ON is deactivated (e.g., to a low level), the second operator 132 may output a high level.

The second operator 132 may include first to fifth logic gates, for example, first to fifth sub-operators 132_1 to 132_ 5. The first sub-operator 132_1 may perform a NAND logic (e.g., NAND) operation ON the output of the first operator 131 and the detection control signal DET _ ON. The second to fourth sub-operators 132_2 to 132_4 may be or include inverters connected in series.

The fifth sub operator 132_5 may perform a NAND logic (NAND) operation on the output of the first operator 131 and the output of the fourth sub operator 132_ 4. The number of inverters between the first sub-operator 132_1 and the fifth sub-operator 132_5 may be changed without limitation as long as the phase of the signal output to the fifth sub-operator 132_5 is not changed.

The third operator 133 may perform a NAND logic (NAND) operation on the first intermediate signal SI1 and the second intermediate signal SI 2. The fourth operator 134 may invert the output of the third operator 133. The fifth operator 135 may perform an operation ON the output of the fourth operator 134 and the detection control signal DET _ ON.

When the detection control signal DET _ ON is activated (e.g., to a high level), the fifth operator 135 may invert and output the output of the fourth operator 134. For example, the fifth operator 135 may output the output of the third operator 134 without any change. When the detection control signal DET _ ON is deactivated (e.g., to a low level), the fifth operator 135 may output a high level.

The fifth operator 135 may include sixth to tenth logic gates, for example, sixth to tenth sub-operators 135_1 to 135_ 5. The sixth sub-operator 135_1 may perform a NAND logic (NAND) operation ON the output of the fourth operator 134 and the detection control signal DET _ ON. The seventh to ninth sub-operators 135_2 to 135_4 may be inverters connected in series.

The tenth sub-operator 135_5 may perform a NAND logic (NAND) operation on the output of the fourth operator 134 and the output of the ninth sub-operator 135_ 4. The number of inverters between the sixth sub-operator 135_1 and the tenth sub-operator 135_5 may be changed without limitation as long as the phase of the signal output to the tenth sub-operator 135_5 is not changed.

The sixth operator 136 may perform a NAND logic (NAND) operation on the output of the second operator 132 and the output of the fifth operator 135. The seventh operator 137 may perform a NOR logic (NOR) operation on the output of the sixth operator 136 and the first signal/EN 1. The output of the seventh operator 137 may be output as the third signal EN 3.

If the first signal/EN 1 is deactivated (e.g., to a high level), the third signal EN3 may be deactivated (e.g., to a low level), regardless of the output of the sixth operator 136. In other words, when no write operation is performed, the corrector 140 may be deactivated.

Fig. 5 shows a first example of the operation of the detector 130 of fig. 4. Referring to fig. 1, 4 and 5, when an external device (e.g., a controller) does not toggle the first and second data strobe signals DQS1 and DQS2, the external device may fix the first and second data strobe signals DQS1 and DQS2 to a low level.

The detection control signal DET _ ON may be fixed to an active state (e.g., a high level). However, as described above, the detection control signal DET _ ON may be activated depending ON the write command. If a write command WR is received as the command CMD, the first signal/EN 1 may be activated (e.g., to a low level).

Even if the first signal/EN 1 is activated, the first operator 131 may output a high level when the first data strobe signal DQS1 and the second data strobe signal DQS2 have a low level. The second operator 132 may invert the output of the first operator 131 and may output a low level.

The third operator 133 may output a high level when the first data strobe signal DQS1 and the second data strobe signal DQS2 have a low level. The fifth operator 135 may output the same high level as the output of the third operator 133.

When the output of the second operator 132 is low level and the output of the fifth operator 135 is high level, the sixth operator 136 may output high level. If the output of the sixth operator 136 is high level, the seventh operator 137 may deactivate the third signal EN3 (e.g., to low level) even when the first signal/EN 1 is in an active state (e.g., low level).

The first operator 131 may output a low level when the first signal/EN 1 is activated and the first data strobe signal DQS1 and the second data strobe signal DQS2 have different phases (e.g., a high level and a low level, respectively). The second operator 132 may invert the output of the first operator 131 and may output a high level.

The third operator 133 may output a high level when the first signal/EN 1 is activated and the first data strobe signal DQS1 and the second data strobe signal DQS2 have different phases (e.g., a high level and a low level, respectively). The fifth operator 135 may output the same high level as the output of the third operator 133.

When the output of the second operator 132 is at a high level and the output of the fifth operator 135 is at a high level, the sixth operator 136 may output a low level. When the output of the sixth operator 136 is low level and the first signal/EN 1 is in an active state (e.g., low level), the seventh operator 137 may activate the third signal EN3 (e.g., to high level).

As shown in fig. 5, the first and second operators 131 and 132 may sense toggling of the first and second data strobe signals DQS1 and DQS2 when the first and second data strobe signals DQS1 and DQS2 are fixed to a low level in a standby state. If toggling of the first data strobe signal DQS1 and the second data strobe signal DQS2 is sensed, the third signal EN3 may be activated and the corrector 140 may be activated.

Fig. 6 shows a second example of the operation of the detector 130 of fig. 4. Referring to fig. 1, 4 and 6, when an external device (e.g., a controller) does not toggle the first and second data strobe signals DQS1 and DQS2, the external device may fix the first and second data strobe signals DQS1 and DQS2 to a high level.

The detection control signal DET _ ON may be fixed to an active state (e.g., a high level). However, as described above, the detection control signal DET _ ON may be activated depending ON the write command. If a write command WR is received as the command CMD, the first signal/EN 1 may be activated (e.g., to a low level).

Even if the first signal/EN 1 is activated, the first operator 131 may output a low level when the first data strobe signal DQS1 and the second data strobe signal DQS2 have a high level. The second operator 132 may invert the output of the first operator 131 and may output a high level.

The third operator 133 may output a low level when the first data strobe signal DQS1 and the second data strobe signal DQS2 have a high level. The fifth operator 135 may output the same low level as the output of the third operator 133.

When the output of the second operator 132 is at a high level and the output of the fifth operator 135 is at a low level, the sixth operator 136 may output a high level. If the output of the sixth operator 136 is high level, the seventh operator 137 may deactivate the third signal EN3 (e.g., to low level) even when the first signal/EN 1 is in an active state (e.g., low level).

The first operator 131 may output a low level when the first signal/EN 1 is activated and the first data strobe signal DQS1 and the second data strobe signal DQS2 have different phases (e.g., a high level and a low level, respectively). The second operator 132 may invert the output of the first operator 131 and may output a high level.

The third operator 133 may output a high level when the first signal/EN 1 is activated and the first data strobe signal DQS1 and the second data strobe signal DQS2 have different phases (e.g., a high level and a low level, respectively). The fifth operator 135 may output the same high level as the output of the third operator 133.

When the output of the second operator 132 is at a high level and the output of the fifth operator 135 is at a high level, the sixth operator 136 may output a low level. When the output of the sixth operator 136 is low level and the first signal/EN 1 is in an active state (e.g., low level), the seventh operator 137 may activate the third signal EN3 (e.g., to high level).

As shown in fig. 6, the third, fourth, and fifth operators 133, 134, and 135 may sense toggling of the first and second data strobe signals DQS1 and DQS2 when the first and second data strobe signals DQS1 and DQS2 are fixed to a high level in a standby state. If toggling of the first data strobe signal DQS1 and the second data strobe signal DQS2 is sensed, the third signal EN3 may be activated and the corrector 140 may be activated.

As described with reference to fig. 5 and 6, if no other command is received after the write command WR is received, the first signal/EN 1 may remain in an active state (e.g., low level). The detector 130 according to some example embodiments of the inventive concept may deactivate the corrector 140 if the first data strobe signal DQS1 and the second data strobe signal DQS2 do not toggle.

Therefore, even if the first signal/EN 1 is kept in the active state because no other command is received after the write command WR is received, it is possible to inhibit, for example, prevent, the corrector 140 from being activated, thereby consuming power consumption.

Fig. 7 shows a third example of the operation of the detector 130 of fig. 4. Referring to fig. 1, 4 and 7, when an external device (e.g., a controller) does not toggle the first and second data strobe signals DQS1 and DQS2, the external device may fix the first and second data strobe signals DQS1 and DQS2 to a low level.

Unlike as described with reference to fig. 4, the detection control signal DET _ ON may be fixed to a deactivated state (e.g., a low level). If the detection control signal DET _ ON is in a deactivated state, the second operator 132 may always output a high level, and the fifth operator 135 may always output a high level.

Therefore, the sixth operator 136 may always output a low level. If the sixth operator 136 outputs a low level, the third signal EN3 may be controlled only by the first signal/EN 1. For example, when the first signal/EN 1 is activated (e.g., to a low level), the third signal EN3 may be activated (e.g., to a high level).

When the first signal/EN 1 is deactivated (e.g., to a high level), the third signal EN3 may be deactivated (e.g., to a low level). For example, upon receiving a write command WR, the detector 130 may activate the corrector 140 during the performance of the write operation.

Fig. 8 illustrates a fourth example of the operation of the detector 130 of fig. 4. Referring to fig. 1, 4 and 8, when an external device (e.g., a controller) does not toggle the first and second data strobe signals DQS1 and DQS2, the external device may fix the first and second data strobe signals DQS1 and DQS2 to a high level.

Unlike as described with reference to fig. 6, the detection control signal DET _ ON may be fixed to a deactivated state (e.g., a low level). If the detection control signal DET _ ON is in a deactivated state, the second operator 132 may always output a high level, and the fifth operator 135 may always output a high level.

Therefore, the sixth operator 136 may always output a low level. If the sixth operator 136 outputs a low level, the third signal EN3 may be controlled only by the first signal/EN 1. For example, when the first signal/EN 1 is activated (e.g., to a low level), the third signal EN3 may be activated (e.g., to a high level).

When the first signal/EN 1 is deactivated (e.g., to a high level), the third signal EN3 may be deactivated (e.g., to a low level). In other words, upon receiving the write command WR, the detector 130 may activate the corrector 140 during the performance of the write operation.

Fig. 9 illustrates a detector 130a according to some example embodiments of the inventive concepts. Referring to fig. 9, the detector 130a may include a first operator 131, a second operator 132a, a third operator 133, a fourth operator 134, a fifth operator 135a, a sixth operator 136, and a seventh operator 137. Each operator may be or correspond to a logic gate, such as a logic gate implemented in Complementary Metal Oxide Semiconductor (CMOS) technology.

When compared to the detector 130 of fig. 4, each of the second operator 132a and the fifth operator 135a may be implemented with an inverter. The detector 130a may not have a function of stopping detection in response to the detection control signal DET _ ON. The detector 130a may have a reduced footprint as compared to the detector 130 of fig. 4.

Fig. 10 illustrates a corrector 140 according to some example embodiments of the inventive concepts. Referring to fig. 10, the corrector 140 may include a first correcting inverter 141 and a second correcting inverter 142. The first correcting inverter 141 may include first to fourth transistors T1 to T4. The first to fourth transistors T1 to T4 may be connected in series between a power supply node and a ground node to which the power supply voltage VDD and the ground voltage VSS are supplied, respectively.

The first transistor T1 and the second transistor T2 may be PMOS transistors. An inverted signal/EN 3 of the third signal EN3 may be transmitted to the gate of the first transistor T1. The third intermediate signal SI3 may be transmitted to the gate of the second transistor T2. The third transistor T3 and the fourth transistor T4 may be NMOS transistors. The third intermediate signal SI3 may be transmitted to the gate of the third transistor T3. The third signal EN3 may be transmitted to the gate of the fourth transistor T4.

The second correcting inverter 142 may include fifth to eighth transistors T5 to T8. The fifth to eighth transistors T5 to T8 may be connected in series between a power supply node to which the power supply voltage VDD and the ground voltage VSS are supplied and a ground node.

The fifth transistor T5 and the sixth transistor T6 may be PMOS transistors. An inverted signal/EN 3 of the third signal EN3 may be transmitted to the gate of the fifth transistor T5. The fourth intermediate signal SI4 may be transmitted to the gate of the sixth transistor T6. The seventh transistor T7 and the eighth transistor T8 may be NMOS transistors. The fourth intermediate signal SI4 may be transmitted to the gate of the seventh transistor T7. The third signal EN3 may be transmitted to the gate of the eighth transistor T8.

The third intermediate signal SI3 may be transmitted to the first correcting inverter 141, and the output of the first correcting inverter 141 may be mixed with the fourth intermediate signal SI 4. The fourth intermediate signal SI4 may be transmitted to the second correction phaser 142, and the output of the second correction phaser 142 may be mixed with the third intermediate signal SI 3. The first and second correction inverters 141 and 142 may implement a cross-coupled latch.

When the duty ratio of the third intermediate signal SI3 does not coincide with the duty ratio of the fourth intermediate signal SI4, there may be a period in which both the third intermediate signal SI3 and the fourth intermediate signal SI4 have a high level or a low level. The corrector 140 may adjust the third intermediate signal SI3 and the fourth intermediate signal SI4 such that, in these periods, the third intermediate signal SI3 and the fourth intermediate signal SI4 change with a slope less than a typical slope.

Likewise, when skew occurs in the third intermediate signal SI3 and the fourth intermediate signal SI4, there may be a period in which both the third intermediate signal SI3 and the fourth intermediate signal SI4 have a high level or a low level. The corrector 140 may adjust the third intermediate signal SI3 and the fourth intermediate signal SI4 such that, in these periods, the third intermediate signal SI3 and the fourth intermediate signal SI4 change with a slope less than a typical slope.

If the third intermediate signal SI3 and the fourth intermediate signal SI4 pass through subsequent inverters (e.g., 116 and 126) (e.g., see fig. 3), the timing at which the third intermediate signal SI3 and the fourth intermediate signal SI4 switch may change. Accordingly, the corrector 140 may improve or restore the duty ratios of the third intermediate signal SI3 and the fourth intermediate signal SI4, and may eliminate or reduce skew.

As shown in fig. 10, if the third signal EN3 is deactivated (e.g., to a low level), it is possible to inhibit, e.g., prevent, a current from flowing through the first correction inverter 141 and the second correction inverter 142. Therefore, no power consumption is generated in the corrector 140.

Fig. 11 illustrates a first strobe buffer 100a according to another embodiment of the inventive concept. Referring to fig. 1 and 11, the first strobe buffer 100a may include a first buffer 110, a second buffer 120, a detector 130, a first corrector 140, and a second corrector 150. When compared to the first strobe buffer 100 of fig. 3, the first strobe buffer 100a may further include a second corrector 150.

The second corrector 150 may receive the output of the first inverter 117 as the fifth intermediate signal SI5 and may receive the output of the second inverter 127 as the sixth intermediate signal SI 6. The second corrector 150 may also receive a third signal EN 3. When the third signal EN3 is activated (e.g., to a high level), the second corrector 150 may correct the fifth and sixth intermediate signals SI5 and SI6 using the fifth and sixth intermediate signals SI5 and SI 6.

For example, the second corrector 150 may correct the duty ratios of the fifth intermediate signal SI5 and the sixth intermediate signal SI6 to target values (e.g., 50%). Further, the second corrector 150 may arrange switching timings of the fifth intermediate signal SI5 and the sixth intermediate signal SI6 to eliminate or reduce skew.

The second corrector 150 is shown to obtain the output of the first inverter 117 as the fifth intermediate signal SI5 and the output of the second inverter 127 as the sixth intermediate signal SI 6. However, the second corrector 150 may be configured to obtain the output of any one of the first inverters 112 to 117 or the output of the first comparator 111 as the fifth intermediate signal SI 5. In addition, the second corrector 150 may be configured to obtain the output of any one of the second inverters 122 to 127 or the output of the second comparator 121 as the fourth intermediate signal SI 4.

As described with reference to fig. 11, one detector may be used to activate or deactivate two or more correctors. As the number of correctors increases, power consumption in the first strobe buffer 100a can be more effectively reduced.

In the foregoing embodiments, the inventive concept has been described with reference to the example of the semiconductor memory device 10. However, the inventive concept can be applied to any semiconductor device that receives a signal (particularly, a strobe signal).

In the above embodiments, some components are referred to by using the term "block". The block may be implemented in hardware configured to execute machine-readable instructions comprising software, such as Integrated Circuits (ICs), application specific ICs (asics), Field Programmable Gate Arrays (FPGAs), and Complex Programmable Logic Devices (CPLDs). Further, the block may include a circuit or Intellectual Property (IP) implemented with semiconductor devices in the IC.

According to some example embodiments of the inventive concepts, the data strobe signal may be corrected only when the data strobe signal transitions to phases different from each other. When the data strobe signals are fixed to the same phase, correction of the data strobe signals is deactivated, and thus, a semiconductor memory device correcting the data strobe signals with reduced power and a method of operating the semiconductor memory device can be provided.

Although exemplary embodiments of the inventive concept have been particularly shown and described, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the appended claims.