Patent Publication Number: US-2023146659-A1

Title: Memory device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to Korean Patent Application No. 10-2021-0152457 filed on Nov. 8, 2021 and Korean Patent Application No. 10-2022-0045198 filed on Apr. 12, 2022 in the Korean Intellectual Property Office, and all the benefits accruing therefrom under 35 U.S.C. 119, the contents of which in their entirety are herein incorporated by reference. 
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to a memory device. 
     2. Description of the Related Art 
     A semiconductor memory device is used to store data. Since a random access memory (RAM) is a volatile memory device, it is mainly used as a main memory device of a computer. Dynamic random access memory (DRAM) is a type of RAM that is volatile and made up of memory cells. In order to efficiently sense data stored in memory cells, a bit line and a complementary bit line are pre-charged with a pre-charging voltage, followed by a charge sharing operation, resulting in a difference between a voltage level of the bit line and a voltage level of the complementary bit line. A sense amplifier senses the data stored in memory cells by amplifying the input voltage difference described above, i.e., the voltage difference dVBL between the bit line and the complementary bit line. 
     Recently, with the development of the electronic industry, the demand for high functionality, high speed, and miniaturization of electronic components has been increasing. Accordingly, in order to improve the integration of a semiconductor memory device, there is a trend to reduce the memory cell region and region of a peripheral circuit for driving the memory cell disposed adjacent to the memory cell region, and to increase a data processing unit to achieve high speed formation of data processing. 
     The bit line sense amplifier may sense and amplify a voltage variation of the memory cell. In this case, an effective sensing margin of the bit line sense amplifier may be reduced due to bit line coupling noise or bit line sense amplifier offset noise. When a voltage variation is less than or equal to a predetermined (or alternatively, desired) level, the bit line sense amplifier may not sense the voltage variation of the bit line. In other words, the offset noise of the bit line sense amplifier may be a factor that reduces the effective sensing margin. 
     SUMMARY 
     One or more example embodiments of the present disclosure provide a memory device for compensating an offset of a bit line sense amplifier. 
     One or more example embodiments of the present disclosure also provide a memory device with improved operation performance. 
     One example embodiment of the present disclosure provides a memory device comprising a memory cell array connected to a first bit line and a complementary bit line, a first bit line sense amplifier configured to sense, amplify and output a first bit line signal and a complementary bit line signal , the first bit line signal output on the first bit line and the complimentary bit line signal output line signal output on the complementary bit line, a charge transfer transistor connected to the first bit line sense amplifier and configured to be gated by a charge transfer signal of a first node, an offset transistor configured to connect the first node and a second node based on an offset removal signal and a pre-charging transistor connected between the second node and a pre-charging voltage line and the pre-charging transistor configured to pre-charge the first bit line or the complementary bit line based on an equalizing signal. 
     Another example embodiment of the present disclosure provides a memory device comprising a memory cell array connected to a sensing bit line and a sensing complementary bit line, a local bit line sense amplifier configured to output a signal output on the sensing bit line to a first bit line and output a complementary signal output on the sensing complementary bit line to a complementary bit line, a first charge transfer transistor connected between the sensing bit line and the first bit line and the first charge transfer transistor configured to be turned on or off based on a charge transfer signal of a first node, and a second charge transfer transistor connected between the sensing complementary bit line and the complementary bit line and the second charge transfer transistor configured to be turned on or off based on the charge transfer signal , wherein the local bit line sense amplifier includes a first equalizing transistor which is connected between a second node and the sensing complementary bit line and gated by a signal of the second node and the local bit line sense amplifier is configured such that a pre-charging voltage is supplied to the second node during an offset removal operation and such that the first node is connected to the second node during the offset removal operation. 
     Another example embodiment of the present disclosure provides a memory device comprising a memory cell array in a memory bank region of a buffer die and including a plurality of memory cells, a plurality of local bit line sense amplifiers between the memory bank regions and the plurality of local bit line sense amplifiers being connected between the memory cell and a first bit line or between the memory cell and a complementary bit line, a global connection controller in a conjunction region of the buffer die and the global connection controller configured to control an operation of the local bit line sense amplifier and a charge transfer transistor configured to connect a sensing bit line of the local bit line sense amplifier to the first bit line and a sensing complementary bit line of the local bit line sense amplifier to and the complementary bit line, in response to a charge transfer signal supplied via a first node of the global connection controller being applied to a gate of the charge transfer transistor, and wherein the global connection controller connects the first node and a second node while supplying a pre-charging voltage to the second node, a gate of a first equalizing transistor of the local bit line sense amplifier being connected to the second node during an offset removal operation. 
     The example embodiments of the present disclosure are not restricted to those set forth herein, and other unmentioned technical aspects will be clearly understood by one of ordinary skill in the art to which the present disclosure pertains by referencing the detailed description of the present disclosure given below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects and features of the present disclosure will become more apparent by describing in detail example embodiments thereof with reference to the attached  FIGS.  1  to  16   , in which: 
         FIG.  1    is a view illustrating explaining a memory device according to some example embodiments; 
         FIG.  2    is a view illustrating the memory cell of  FIG.  1   ; 
         FIG.  3    is a view illustrating a memory cell array to which the sense amplifier according to some example embodiments is applied; 
         FIG.  4    is a circuit diagram illustrating a bit line sense amplifier according to some example embodiments; 
         FIG.  5    is a circuit diagram illustrating the local bit line sense amplifier according to some example embodiments; 
         FIG.  6    is an equivalent circuit diagram of the bit line sense amplifier according to some example embodiments; 
         FIG.  7    is a graph illustrating an equalizing voltage of the bit line sense amplifier according to some example embodiments; 
         FIG.  8    is a graph illustrating a bit line voltage of the bit line sense amplifier according to some example embodiments; 
         FIG.  9    is a timing diagram illustrating an operation of the bit line sense amplifier according to some example embodiments; 
         FIG.  10    is a timing diagram illustrating an operation of the bit line sense amplifier according to some example embodiments; 
         FIG.  11    is a circuit diagram illustrating the bit line sense amplifier according to some example embodiments; 
         FIG.  12    is a timing diagram illustrating an operation of the bit line sense amplifier according to some example embodiments; 
         FIG.  13    is a block diagram illustrating a stacked memory device according to some example embodiments; 
         FIG.  14    is a diagram illustrating a semiconductor package according to some example embodiments; 
         FIG.  15    is a diagram illustrating an implemented example of a semiconductor package according to some example embodiments of the present disclosure; and 
         FIG.  16    is a diagram illustrating the semiconductor package according to some example embodiments. 
     
    
    
     DETAILED DESCRIPTION OF THE EXAMPLE EMBODIMENTS 
     Hereinafter, various example embodiments of the present disclosure will be described with reference to the attached drawings: 
       FIG.  1    is a view illustrating explaining a memory device according to some example embodiments. 
     Referring to  FIG.  1   , a memory device  100  may be a storage device based on a semiconductor device. For example, the memory device  100  may be dynamic random access memory (DRAM) such as double data rate static DRAM (DDR DRAM), single data rate SDRAM (SDR SDRAM), low power DDR SDRAM (LPDDR SDRAM), low power SDR SDRAM (LPSDR SDRAM) or direct RDRAM (Rambus DRAM), or any other volatile memory device. In particular, the memory device may be a device to which a standard protocol such as DDR4 or DDR5 is applied. 
     In one example embodiment, the number of data pins to which the DDR 4  or DDRS standard protocol is applied may be four, eight, or sixteen, and the number of data pins of the semiconductor memory device  100  according to the present disclosure may be sixteen. Hereinafter, the description of the number of data pins of a memory system  50  used in the description of the present invention may be applied according to the standard protocol for the dynamic random access memory, but the present disclosure is not limited thereto. 
     The memory device  100  may output data via data lines DQ in response to a command CMD, an address ADDR, and control signals received from an external device, for example, a memory controller. For example, an external memory controller may transmit a command CM, address ADDR and control signals to the memory device  100  and in response, the memory device  100  may output data on the data lines DQ. The memory device  100  includes a memory cell array  110 , a command decoder  112 , a control logic  114 , an address buffer  120 , a row decoder  130 , a column decoder  140 , a sense amplifier array  150 , and a data input/output circuit  160 . 
     The memory cell array  110  includes a plurality of memory cells supplied in the form of a matrix disposed in rows and columns. The memory cell array  110  includes a plurality of word lines and a plurality of bit lines BL connected to memory cells. The plurality of word lines may be connected to rows of the memory cells, and the plurality of bit lines BL may be connected to columns of the memory cells. 
     According to some example embodiments, the memory cell may include a normal memory cell configured to store data and a redundant memory cell. The redundant memory cell is used to relieve a normal memory cell when the normal memory cell is defective. 
     The command decoder  112  decodes commands received from the memory controller, for example, a write enable signal (/WE), a low address strobe signal (/RAS), a column address strobe signal (/CAS), and a chip selection signal (/CS). The command CMD may include an active command, a read command, a write command, and a pre-charge command 
     In response to the decoded command, the control logic  114  may generate all kinds of control signals necessary (or alternatively, desired) for an access operation for the memory cell array  110 , for example, a write operation, a read operation, and a pre-charge operation. 
     The address buffer  120  receives the address ADDR from the memory controller that is an external device. The address ADDR includes a row address RA for addressing a row of the memory cell array  110  and a column address CA for addressing a column of the memory cell array  110 . The address buffer  120  may transmit the row address RA to the row decoder  130  and transmit the column address CA to the column decoder  140 . 
     The row decoder  130  may select any one of the plurality of word lines WL connected to the memory cell array  110 . The row decoder  130  may decode the row address RA received from the address buffer  120 , select any one of word lines corresponding to the row address RA and activate the selected word line. Upon the activation of a word line, i.e., an operation of enabling the word line, a high-power voltage VPP higher than a power voltage VDD may be applied to a gate of an access transistor of the memory cell. For example, the high-power voltage VPP may be applied to a gate of the access transistor of the memory cell in response to the activation of the word line. 
     The column decoder  140  may select a desired (or alternatively, predetermined) bit line from the plurality of bit lines BL of the memory cell array  110 . The column decoder  140  may decode the column address CA received from the address buffer  120  to select the desired bit line BL corresponding to the column address CA. 
     The sense amplifier arrays S/A  150  are connected to the bit lines BL of the memory cell array  110 . The sense amplifier array  150  senses a voltage change of the bit line selected from the plurality of bit lines BL and amplifies and outputs the voltage change. The data input/output circuit  160  may output data based on the sensed and amplified voltage from the sense amplifier array  150  to the outside via the data lines DQ. Any bit line sense amplifier BLSA may be connected to a bit line pair composed of a first bit line BL and a complementary bit line BLB to sense and amplify a potential represented in the bit line. The detailed connection between the bit line sense amplifier and the bit line pair will be described later in  FIGS.  3  and  4   . 
     The sense amplifier array  150  may receive an isolation signal ISO and an offset removal signal OC from the control logic  114 . The sense amplifier array  150  may perform an offset removal operation according to the isolation signal ISO and the offset removal signal OC. For example, the offset refers to characteristics such as, for example, a threshold voltage difference, between semiconductor elements constituting the sense amplifier array  150 . 
       FIG.  2    is a view illustrating the memory cell of  FIG.  1   . 
     Referring to  FIGS.  1  and  2   , a memory cell MC included in the memory cell array is connected to each of the word lines WL and the bit lines BL. 
     The memory cell MC is composed of a cell transistor MTR and a cell capacitor C. The memory device  100  may perform a read operation or a refresh operation based on a charge amount of the cell capacitor C included in the memory cell MC. In this case, a first bit line BL connected to the memory cell MC is pre-charged with a pre-charging voltage Vpre. Then, with the activation of the word line WL, the charge sharing operation occurs between a charge of the first bit line BL charged with the pre-charging voltage Vpre and a charge of the cell capacitor C of the memory cell MC. Through the charge sharing operation, a voltage of the first bit line BL may decrease or increase by a voltage variation V from the pre-charging voltage Vpre. Each of the sense amplifiers of the sense amplifier array  150  may sense and amplify the voltage variation V. 
       FIG.  3    is a view illustrating a memory cell array to which the sense amplifier according to some example embodiments is applied. 
     Referring to  FIG.  3   , the memory device  300  includes a plurality of memory cell arrays  110 _ 1  to  110 _ n  and a plurality of sense amplifiers  150 _ 1  to  150 _ n.    
     Each of the plurality of sense amplifiers  150 _ 1  to  150 _ n  may include a plurality of bit line sense amplifiers BLSA. The bit line sense amplifiers BLSA may be implemented with the sense amplifier array  150  described in  FIGS.  1  to  2   . 
     A plurality of bit line pairs BL and BLB connected to the plurality of memory cell arrays  110 _ 1  to  110 _ n  may be connected to each of the plurality of bit line sense amplifiers BLSA, respectively. Each of the bit line sense amplifiers BLSA may be cross-coupled differential sense amplifiers implemented as a P-type sense amplifier and an N-type sense amplifier. 
     Each of the bit line sense amplifiers BLSA is a circuit device that normally operates during operation of the semiconductor memory device, and is distinguished from dummy sense amplifiers  150 - 1  and  150 - n  implemented in a region except a region where the bit line sense amplifiers  150 _ 2  to  150 _ n - 1  are implemented. 
     According to some example embodiments, an odd bit line of the memory cell array  110 _ 1  may be connected to the first bit line BL, and an even bit line thereof may be connected to the complementary bit line BLB. The bit line sense amplifier  150 - 2  may be connected to each of the bit line pairs BL and BLB in both directions. For example, the bit line sense amplifier  150 - 2  may be connected to an odd-numbered bit line (e.g., BL 1 , BL 3 , BL 5 , . . . etc.) of the first memory cell array  110 _ 1  on the left, namely, the bit line BL, whereas the bit line sense amplifier  150 - 2  is an even-numbered bit line (e.g., BL 0 , BL 2 , BL 4 , . . . etc.) of the second memory cell array  110 _ 2  on the right, namely, the complementary bit line BLB. 
     In the sensing operation of the bit line sense amplifier, when the potential of the bit line BL is a high potential, the potential of the complementary bit line BLB becomes a low potential. Meanwhile, in the sensing operation of the bit line sense amplifier, when the potential of the bit line BL is a low potential, the potential of the complementary bit line BLB becomes a high potential. 
     Although not illustrated, an odd-numbered bit line of the second memory cell array  110 _ 2  may be connected to the bit line sense amplifier  150 - 3  by extending in a direction opposite to the bit line sense amplifier  150 - 2 . 
       FIG.  4    is a circuit diagram illustrating a bit line sense amplifier according to some example embodiments. 
     Referring to  FIG.  4   , according to some example embodiments, the memory device  300  includes a global connection controller  310  and a plurality of local bit line sense amplifiers  150 _ k . Each of the local bit line sense amplifiers  150  is connected to the global connection controller  310  via a charge transfer transistor MCT. The charge transfer transistor MCT may be turned on according to the charge transfer signal CT (for example, logic high in the case of an N-type transistor), and the charge transfer signal CT may be logic high or logic low according to a voltage of a node N 1 . 
     The global connection control unit  310  may include CTPS transistors MP 1  and MN 1 , an isolation transistor MP 2 , an offset transistor MN 2 , an internal power supply transistor MN 3 , and a pre-charging transistor MN 4 . For convenience of explanation,  FIG.  4    illustrates the global connection control unit  310  corresponding to any one column of the charge transfer transistor MCT included in the local bit line sense amplifier  150 _ k , and according to various example embodiments, the global connection control unit  310  may be implemented to correspond to each column of the local bit line sense amplifier  150 _ k.    
     According to some example embodiments, transfer gate transistors MP 1  and MP 2  are connected in series between a transfer gate voltage VTG line and a ground line by using the node N 1  to which the charge transfer signal CT is applied, as a common node, and a charge transfer pre-sensing bar signal CTPSB is applied to a gate of a P-type transfer gate transistor MP 1 , and a charge transfer off signal CTOFF is applied to a gate of a N-type transfer gate transistor MN 1 . 
     The local bit line sense amplifier  150 _ k  is connected to the plurality of bit lines BL and the complementary bit line BLB, respectively, and is connected as a local bit line sense amplifier  150 _ k . The local bit line sense amplifiers  150 _ k  connect the sensing bit line SBL or the sensing complementary bit line SBL to the bit line BL or the complementary bit line BLB according to the isolation transistor MP 2  and charge transfer transistors MCT and MCTB connected to the memory cell. The charge transfer transistors MCT and MCTB may be implemented as N-type transistors according to some example embodiments, and one end of the charge transfer transistors is connected to the sensing bit line/sensing complementary bit line SBL/SBLB of the local bit line sense amplifier  150  and the other end thereof is connected to the bit line/complementary bit line BL/BLB. The charge transfer transistors MCT and MCTB are turned on/off according to the charge transfer signal CT supplied to the gate. For example, in the case of implementing the charge transfer transistor as the N-type transistor, the transistor transfer signal CT may be turned on when the charge transfer signal CT is logic high. In various example embodiments the isolation transistor MP 2 , the offset transistor MN 2 , the internal power supply transistor MN 3 , and the pre charge transistor MN 4  (as well as other transistors) may each be implemented as either a P-type or an N-type transistor. 
     According to some example embodiments, the isolation transistor MP 2  is connected between an isolation voltage line VISO and the node N 1 , and a restore bar signal RSTB is applied to the gate. According to some example embodiments, the isolation transistor MP 2  may be implemented as a P-type transistor, and the isolation transistor MP 2  is activated and turned on when the restore bar signal RSTB is logic low. According to another example embodiment, in the case of implementing the isolation transistor as the N-type transistor, the transistor may be activated and turned on when the restoration signal RST is logic high. 
     According to some example embodiments, the offset transistor MN 2  is connected between a node N 2  and the node N 1 , and the offset removal signal OC is applied to the gate. According to some example embodiments, the offset transistor MN 2  may be implemented as the N-type transistor, and the offset transistor MN 2  may be turned on when the offset removal signal OC is logic high. According to some example embodiments, the offset transistor may be implemented as the P-type transistor, and the offset transistor may be turned on when the offset removal signal OC is logic low. 
     According to some example embodiments, the internal power supply transistor MN 3  is connected between an internal power supply line Vinta 2  and the node N 2 , and an internal power enable signal is applied to the gate. The internal power supply transistor MN 3  supplies the internal power Vinta 2  to the node N 2  according to the internal power enable signal. According to some example embodiments, the internal power supply transistor MN 3  may be the N-type transistor, but the present disclosure is not limited thereto and the internal power supply transistor MN 3  may be implemented as the P-type transistor. 
     According to some example embodiments, the pre-charge transistor MN 4  is connected between the pre-charging voltage VBL line and the node N 2 , and the equalizing signal EQ is applied to the gate. According to some example embodiments, the pre-charge transistor MN 4  may be the N-type transistor, but the present disclosure is not limited thereto and the pre-charge transistor may be implemented as the P-type transistor. 
     According to the operation of the bit line sense amplifier, the transfer gate voltage VTG is applied to the node N 1 , a ground voltage GND may be applied to the node N 1 , the isolation voltage VISO may be applied to the node N 1 , or the node N 1  may be connected to the node N 2 . 
     The node N 2  may be connected to the node N 1  according to the offset removal signal OC, receive a cell data storage voltage Vinta 2  according to the memory cell enable signal, or receive an equalizer voltage VBL according to an equalizer enable signal PEQ. 
     In a memory device of a charge transfer pre-sensing manner, a sensing voltage Vsense of the memory cell is output from the cell transistor MTR and a signal Vcell stored in the sensing bit line SBL is output to a source terminal of the charge transfer transistors MCT and MCTB. Accordingly, the charge transfer transistor MCT may output a value obtained by subtracting a threshold voltage VTH from a gate-source voltage Vgs (Vout=Vgs-VTH). However, with an increase in the integration of the memory devices and a decrease in the size of memory cells, the charge transfer transistor MCT and the charge transfer transistor MCTB may result in a process mismatch. When the threshold voltage (or threshold voltage VTH) is changed due to the mismatch of the charge transfer transistor, the sensing voltage of the memory cell may also produce an error. However, in order to compensate for the threshold voltage offset of the charge transfer transistor caused by the mismatch, the internal power supply voltage Vinta 2  is additionally supplied to the node N 1  via the internal power supply transistor MN 3  during the offset removal operation, thereby strengthening the charge transfer signal CT supplied to the gate of the charge transfer transistor MCT and minimizing or reducing an offset effect of the threshold voltage VTH caused by the mismatch. 
       FIG.  5    is a circuit diagram illustrating the local bit line sense amplifier according to some example embodiments. 
     Referring to  FIGS.  4  and  5   , the local bit line sense amplifier t 150  is connected between a first control line LA to which a first control signal LA is supplied and a second control line LAB to which a second control signal LAB is supplied, and is connected between the bit line BA and the complementary bit line BLB. 
     The local bit line sense amplifier  150  includes P-type amplifiers MP 11  and MP 12  of which one end is connected to the first control line LA, and N-type amplifiers MN 11  and MN 12  of which one end is connected to the second control line LAB. The other ends of the P-type amplifiers MP 11  and MP 12  and the N-type amplifiers MN 11  and MN 12  may each be electrically connected to the sensing bit line SBL or the sensing complementary bit line SBLB to which the bit line BA and the complementary bit line BLB are connected, respectively. An amplification transistor MP 11  and an amplification transistor MP 12 , and an amplification transistor MN 11  and an amplification transistor MN 12  are connected to each other in a cross-coupling structure. 
     Specifically, the amplification transistor MP 11  is connected between the first control line LA and the sensing bit line SBL, and the gate is connected to the sensing complementary bit line SBLB. The amplification transistor MP 12  is connected between the first control line LA and the sensing complementary bit line SBLB, and the gate is connected to the sensing bit line SBL. The amplification transistor MN 11  is connected between the second control line LAB and the sensing bit line SBL, and the gate is connected to the sensing complementary bit line SBLB. The amplification transistor MN 12  is connected between the second control line LAB and the sensing complementary bit line SBLB, and the gate is connected to the sensing bit line SBL. 
     According to some example embodiments, the local bit line sense amplifier  150  includes a first equalizing transistor MP 13  and a second equalizing transistor MN 13 . The second equalizing transistor MN 13  is connected between the sensing bit line SBL and a node SBLB, and electrically connects the bit line BL and the complementary bit line BLB when a second equalizing signal EQ is applied to the gate (e.g., EQ enable). The first equalizing transistor MP 13  is connected to a node N 2 , namely, a VPEQ node and a sensing complementary bit line SBLB node, and pre-charges the electrically connected bit line BL and complementary bit line BLB with the pre-charging voltage, when a first equalizing signal PEQ is applied to a gate. According to some example embodiments, the first equalizing transistor MP 13  may be the P-type transistor, and the second equalizing transistor MN 13  may be the N-type transistor. 
     According to some example embodiments, the local bit line sense amplifier  150  further includes charge transfer transistors MCT and MCTB. A first charge transfer transistor MCT makes or interrupts a connection between the bit line BL and the sensing bit line SBL according to the charge transfer signal CT. A second charge transfer transistor MCTB makes or interrupts a connection between the complementary bit line BLB and the sensing complementary bit line SBLB according to the charge transfer signal CT. According to some example embodiments, the charge transfer transistor may be implemented as the N-type transistor as illustrated in the drawings, but the present invention is not limited thereto and the charge transfer transistor may be implemented as the P-type transistor according to various example embodiments. 
     According to some example embodiments, the gate of the charge transfer transistors MCT and MCTB is connected to the node N 1  in  FIG.  4   , and thus the charge transfer signal CT may be applied to the gate. The offset transistor MN 2  may make or interrupt a connection between the node N 2  and the node N 1  according to the offset removal signal OC. 
       FIG.  6    is an equivalent circuit diagram of the bit line sense amplifier according to some example embodiments, and  FIG.  7    is a graph illustrating an equalizing voltage of the bit line sense amplifier according to some example embodiments.  FIG.  8    is a graph illustrating a bit line voltage of the bit line sense amplifier according to some example embodiments. 
     Referring to  FIGS.  4  and  6   , when enabling the offset removal signal OC, that is, during an offset removal operation, the offset transistor MN 13  electrically connects the node N 1  and the node N 2 . The gate of the charge transistor MCT and MCTB may be connected to the node N 1 , and the node N 2  may be connected to the node N 1  according to the offset removal signal OC according to various example embodiments as described above, or the node N 2  may receive the internal power voltage Vinta 2  or receive the pre-charging voltage VBL. 
     When the node N 1  and the node N 2  are electrically connected to each other, the gate of the cell transistor (e.g., MTR 1 ) is connected to a drain terminal of the cell transistor MTR 1  to receive the pre-charging voltage (supplying VBL to the VPEQ node). A charge stored in a capacitor C 1  of the memory cell is shared with the VPEQ node (N 2  in  FIG.  4   ) due to a gate-drain connection of the cell transistor MTR 1 . Another memory cell MTR 2  connected to the same VPEQ node (N 2  in  FIG.  4   ) is also shared with a drain of the cell transistor MTR 2  stored in the capacitor C 2  in the same manner According to the equivalent circuit, a voltage of the VPEQ node (N 2  of  FIG.  4   ) increases over time as illustrated in  FIG.  7   , and a voltage Vb 1  of the bit line BL or a voltage Vblb of the complementary bit line BL is represented as a threshold voltage VTH offset as illustrated in  FIG.  8   . 
       FIG.  9    is a timing diagram illustrating an operation of the bit line sense amplifier according to some example embodiments.  FIG.  10    is a timing diagram illustrating an operation of the bit line sense amplifier according to some example embodiments. An X-axis indicates time and a Y-axis indicates a signal level in  FIGS.  9  and  10   . 
     The bit line sense amplifier  150  sequentially performs a pre-charging operation, the offset removal operation, the charge sharing operation, a charge transfer operation, a sensing operation, and a restoring operation. In the illustrated example, it is assumed that the memory cell stores data “ 1 ”. 
     Referring to  FIGS.  4 ,  5 ,  9 , and  10   , the bit line sense amplifier  300  first performs the pre-charge operation in a first section (pre-charge section, section  0 -t 1 ). An equalizing signal EQ is applied to a gate of a logic high pre-charge transistor MN 4 , and the pre-charge transistor MN 4  is turned on to supply a pre-charging voltage VBL via the node N 2 . The pre-charging voltage VBL of the node N 2  pre-charges the bit line BL and the complementary bit line BLB. In this case, the restore bar signal RSTB is logic low, and the isolation transistor MP 2  that has a P type, is turned on to supply a voltage corresponding to the isolation voltage to the node N 2 . 
     As illustrated in  FIG.  10   , the charge transfer signal CT connected to the node N 2  becomes logic high to turn on the charge transfer transistor MCT, and when a CTPSB signal is logic high and a CTOFF signal is logic low, the transfer gate transistors MP 1  and MN 1  are turned off, respectively. Meanwhile, the offset removal signal OC is logic low to turn off the offset transistor MN 2 , and thus, the node N 1  and the node N 2  are not connected to each other. Accordingly, the sensing bit line SBL, and the sensing complementary bit line SBLB, and the bit line BL and the complementary bit line BLB are uniformly pre-charged with the pre-charging voltage VBL. 
     Upon reviewing a second section (offset removal section, section t 1 -t 2 ), the offset removal signal CO becomes logic high to turn on the offset transistor MN 2 , and the restore bar signal RSTB becomes logic high to turn off the isolation transistor MP 2 . Each of the transfer gate transistors MP 1  and MN 1  are kept turned off when the CTPSB signal is logic high and the CTOFF signal is logic low, respectively. An internal power enable signal Vinta 2  becomes logic high to turn on the internal power supply transistor MN 3 . The first equalizing signal EQ is logic high to turn on the first pre-charging transistor MN 4 . The second equalizer signal PEQ is logic high to turn off the second equalizer transistor MP 13 . 
     The pre-charging voltage VBL supplied to the node N 2  according to the transistor connection in the second section is distributed to the node N 1  via the turned-on offset transistor MN 2 . The node N 1  may become lower than the isolation voltage VISO, as may be seen from the voltage level of the charge transfer signal CT. However, the charge transfer transistors MCT and MCTB at both ends of the bit line sense amplifier  150  are turned on, and the internal power supply transistor MN 3  and the pre-charge transistor MN 4  are turned on, thus supplying the internal power voltage Vinta 2  as well as the pre-charging voltage VBL to the node N 2 . In other words, even if there is a threshold voltage difference VTH_MCT and VTH_MCTB between the charge transfer transistors MCT and MCTB, even the internal power voltage Vinta 2  may be supplied to the charge transfer signal by the offset transistor MN 2 , thus reducing an influence of the threshold voltage offset. 
     Since the charge transfer transistors MCT and MCTB are turned on, the sensing bit line and the sensing complementary bit line SBL/SBLB output the stored charge to the bit line and the complementary bit line BL/BLB. However, since a control signal LA/LAB is at a desired (or alternatively, predetermined) intermediate level voltage, P-type amplifiers MP 11  and MP 12  and N-type amplifiers NN 11  and NN 12  fail to perform amplification. 
     In a third section (charge sharing section, section t 2 -t 3 ), when the CTOFF signal becomes logic high, the transfer gate transistor MN 1  is turned off. The CTPSB signal is logic high, the transfer gate transistor MP 1  is turned off, and the isolation transistor MP 2  is turned off, and the offset transistor MN 2  is also turned off. However, the internal power supply transistor MN 2  and the pre-charging transistor MN 4  are kept turned on from the second section. According to such connection, in the third section, the internal power voltage Vinta 2  and the pre-charging voltage VBL supplied to the node N 2  are added together to generate an equalizing voltage VPEQ and stored in the node N 2 . The node N 1 , namely, CT, becomes lower than the voltage level in the second section by the turned-on transfer gate transistor MN 1 . 
     When the charge transfer signal CT is logic low by lowering the voltage level of the node N 1 , the charge transfer transistors MCT and MCTB are turned off, and the transistor MN 13  is turned on by the logic high equalizing signal EQ to generate the charge sharing operation between a charge stored in a cell capacitor of the memory cell and a charge stored in the sensing bit line SBL or the sensing complementary bit line BLB. For example, when data “ 1 ” is stored in the memory cell, the sensing bit line SBL increases by a desired (or alternatively, predetermined) level due to the charge sharing operation, and when data “ 0 ” is stored in the memory cell, the sensing bit line SBL decreases by a desired (or alternatively, predetermined) level due to the charge sharing operation. In this case, since the charge transfer transistors MCT and MCTB are turned off in the bit line and the complementary bit line BLB, their logic states are kept similar to each other in the second section. 
     In a fourth section (charge transfer section, section t 3 -t 4 ), when the CTOFF signal becomes logic low and the CTPSB signal becomes logic low, the transfer gate transistor MP 1  is turned on, and the transfer gate transistor MN 1  is turned off. The equalizing signals EQ and PEQ become logic low to turn off the transistor MN 4  and the transistor MN 13  in  FIG.  5   , and to turn on the transistor MP 13 . In addition, the offset transistor MN 2  and the internal power supply transistor MN 3  are turned off. 
     According to the transistor connection of the fourth section, the transfer gate voltage VTG is supplied to the node N 1  via the transistor MP 1 . As the charge transfer signal CT becomes logic high according to the voltage level of the node N 1 , the charge transfer transistors MCT and MCTB are turned on such that the charge stored in the sensing bit line and the sensing complementary bit line SBL/SBLB are output to the bit line and the complementary bit line BL/BLB via the charge transfer transistors MCT and MCTB. In this case, since the control signals LA and LAB have a desired (or alternatively, predetermined) intermediate level voltage, the P-type amplifiers MP 11  and MP 12  in  FIG.  5    and the N-type amplifiers MN 11  and MN 12  in  FIG.  5    fail to amplify the amount of charge stored in the sensing bit line and the sensing complementary bit line SBL/SBLB, and irrevocably outputs the amount of charge stored in the sensing bit line and the sensing complementary bit line SBL/SBLB, to the bit line and the complementary bit line BL/BLB, after the charge sharing operation. 
     In a fifth section (sensing section, section t 4 -t 5 ), the turn-on/turn-off states of the transfer gate transistor MP 1 , the transfer gate transistor MN 1 , the equalizing transistors MN 4  and the equalizing transistor MN 13  in  FIG.  5   , the offset transistor MN 2  and the internal power supply transistor MN 3  are kept identical to those in the fourth section. However, as the control signals LA/LAB transition to logic high and logic low, the P-type amplifiers MP 11  and MP 12  in  FIG.  5    and the N-type amplifiers MN 11  and MN 12  in  FIG.  5    are activated to amplify the amount of charge stored in the sensing bit line and the sensing complementary bit line SBL/SBLB, and a voltage according to the amplified amount of charge is output to the bit line and the complementary bit line BL/BLB. 
     In a sixth section (restore section, section t 5 -t 6 ), when the CTOFF signal maintains logic low and the CTPSB signal changes from logic low to logic high, the transfer gate transistor MP 1  is turned off again, and the transfer gate transistor MN 1  is kept turned off. As the restore bar signal RSTB transitions to logic low, the isolation transistor MP 2  is turned on. The control signals LA/LAB are maintained like the fourth section, and thus the P-type amplifiers MP 11  and MP 12  in  FIG.  5    and the N-type amplifiers MN 11  and MN 12  in  FIG.  5    perform the amplification. As the isolation voltage VISO is supplied to the node N 1 , the charge transfer signal CT becomes logic high, and the charge transfer transistors MCT and MCTB are turned on. 
     The bit line and the complementary bit line BL/BLB may be sensed with the sensing bit line and the sensing complementary bit line SBL/SBLB by the charge transfer transistors MCT and MCTB and may thus be charged or discharged with the amplified charge. 
     Hereinafter, the pre-charging operation is performed again in the section of t 6  to t 8  in  FIG.  9   , and the offset removal operation, the charge sharing operation, the charge transfer operation, the sensing operation, and the restoring operation are sequentially performed again in the section after t 8 . 
       FIG.  11    is a circuit diagram illustrating the bit line sense amplifier according to some example embodiments. 
     Referring to  FIG.  11   , according to some example embodiments, the global bit line sense amplifier  300  includes a global connection controller  310 ′ and a plurality of local bit line sense amplifiers  150 _ k . Each of the local bit line sense amplifiers  150  is connected to the global connection controller  310  via the charge transfer transistor MCT. The charge transfer transistor MCT may be turned on according to the charge transfer signal CT (for example, logic high in the case of the N-type transistor), and the charge transfer signal CT may be logic high or logic low according to the voltage of the node N 1 . 
     The global connection controller  310 ′ may include CTPS transistors MP 1  and MN 1 , the isolation transistor MP 2 , an offset transistor MN 2 , a first internal power supply transistor MN 3 , a second internal power supply transistor MNS, and the pre-charging transistor MN 4 . For convenience of explanation,  FIG.  11    illustrates the global connection controller  310  corresponding to any one column of the charge transfer transistor MCT included in the local bit line sense amplifier  150 _ k , and according to various example embodiments, the global connection controller  310  may be implemented to correspond to each column of the local bit line sense amplifier  150 _ k.    
     According to some example embodiments, the transfer gate transistors MP 1  and MP 2  are connected in series between the transfer gate voltage VTG line and the ground line by using the node N 1  to which the charge transfer signal CT is applied, as a common node, and a charge transfer pre-sensing bar signal CTPSB is applied to a gate of a first P-type transistor MP 1 , and a charge transfer off signal CTOFF is applied to a gate of a first N-type transistor MN 1 . 
     The local bit line sense amplifier  150 _ k  is connected to the plurality of bit lines BL and the complementary bit line BLB, respectively, and is connected as a local bit line sense amplifier  150 _ k . The local bit line sense amplifiers  150 _ k  connect the sensing bit line SBL or the sensing complementary bit line SBL to the bit line BL or the complementary bit line BLB according to the isolation transistor MP 2  connected to the memory cell. According to some example embodiments, the isolation transistor MP 2  is connected between the isolation voltage line VISO and the node N 1 , and the restore bar signal RSTB is applied to the gate. The isolation transistor MP 2  isolates the bit line BL and the complementary bit line BLB from a sensing bit line SBL and a sensing complementary bit line SBLB according to the restore bar signal RSTB. According to some example embodiments, the isolation transistor MP 2  may be implemented as the P-type transistor and is activated and turned on when the restore bar signal RSTB is logic low. According to another example embodiment, when the isolation transistor is implemented as the N-type transistor, the transistor may be activated and turned on when the restoration signal RST is logic high. 
     According to some example embodiments, the offset transistor MN 2  is connected between the VPEQ node and the node N 1 , and the offset removal signal OC is applied to the gate. According to some example embodiments, a first internal power transistor MN 5  is connected between a first internal power voltage Vinta line and a LA node, and a first memory cell enable signal is applied to the gate. According to some example embodiments, the second internal power transistor MN 3  is connected between a second internal power voltage Vinta 2  line and the LA node, and a second memory cell enable signal is applied to the gate. In accordance with some example embodiments, the pre-charging transistor MN 4  is connected between the pre-charging voltage VBL line and a VPEQ node, and the equalizing signal EQ is applied to the gate. 
       FIG.  12    is a timing diagram illustrating an operation of the bit line sense amplifier according to some example embodiments. The X-axis of  FIG.  12    indicates time and the Y-axis indicates a signal level. 
     The bit line sense amplifier  150  sequentially performs the pre-charging operation, the offset removal operation, the charge sharing operation, the charge transfer operation, the sensing operation, and the restoring operation. In the illustrated example, it is assumed that the memory cell has stored data “ 1 ”. The difference from  FIG.  10    will be mainly described, and redundant descriptions will be omitted herein. 
     Referring to the graphs of  FIGS.  9  and  12    based on the bit line sense amplifier of  FIGS.  5  and  11   , the bit line sense amplifier  300 ′ first performs the pre-charging operation in the first section (pre-charge section, section  041 ). In the first section, the offset removal signal OC is logic low to turn off the offset transistor MN 2 , and thus, the node N 1  and the VPEQ node are not connected to each other. Accordingly, the sensing bit line SBL and the sensing complementary bit line SBLB, and the bit line BL and the complementary bit line BLB are uniformly pre-charged with the pre-charging voltage VBL. 
     Upon reviewing the second section (offset removal section, section t 1 -t 2 ), the offset removal signal OC becomes logic high to turn on the offset transistor MN 2 , and the isolation transistor MP 2  is turned off according to the restore bar signal RSTB. Each of the transfer gate transistors MP 1  and MN 1  is kept turned off. The internal power enable signal Vinta 2  becomes logic high to turn on a first internal power supply transistor MN 5  and a second internal power supply transistor MN 3 , and the first equalizing signal EQ becomes logic high to turn on the first pre-charging transistor MN 4 . The second equalizer signal PEQ becomes logic high to turn off the second equalizer transistor MP 13 . 
     The voltage of the VPEQ node connected via the offset transistor MN 2  is distributed to the node Ni. The node N 1  is lower than the voltage level in the first section, as seen in the voltage level of the charge transfer signal CT. However, since the voltage level of the node N 1  is not logic low, the charge transistors MCT and MCTB at both ends of the bit line sense amplifier  150  are turned on, and the first internal power supply transistor MN 5  and the second internal power supply transistor MN 3  are turned on to supply the first internal power voltage Vinta and the internal power voltage Vint to the LA node. Then, the pre-charging transistor MN 4  is turned on to supply the pre-charging voltage VBL to the VPEQ node. The voltage of the LA node is increased by the first and second internal power voltages, and the sensing bit line and the sensing complementary bit line SBL/SBLB receive the voltage of the VPEQ node supplied via the equalizing transistor MP 13 , thus gradually increasing the voltage level. 
     Since the charge transfer transistors MCT and MCTB are turned on, the sensing bit line and the sensing bit complementary line SBL/SBLB output the stored charge to the bit line and complementary bit line BL/BLB, but since the control signals LA/LAB are at the same voltage level, the P-type amplifiers MP 11  and MP 12  and the N-type amplifiers NN 11  and NN 12  fail to perform the amplification. 
     In the third section (charge sharing section, section t 2 -t 3 ), the transfer gate transistor MN 1  is turned on, the transfer gate transistor MP 1  is turned off, and the isolation transistor MP 2  and the offset transistor MN 2  are turned off. However, the first and second internal power supply transistors MN 3  and MN 5  and the pre-charging transistor MN 4  are kept turned off from the second section. In the third section according to such connection, in the VPEQ node, the pre-charging voltage VBL is supplied to the bit line sense amplifier  150  as the equalizing voltage VPEQ. The node N 1 , namely, CT, is lower than the voltage level of the second section by the turned-on transfer gate transistor MN 1 . Since the charge transfer transistors MCT and MCTB are turned off according to the voltage level of the node N 1 , and the equalizing transistor MN 13  is turned on by the equalizing signal EQ that is logic high, the charge sharing operation occurs between the charge stored in the cell capacitor of the memory cell and the charge stored in the sensing bit line SBL or the sensing complementary bit line BLB. For example, when data “ 1 ” is stored in the memory cell, the sensing bit line SBL increases by the predetermined (or alternatively, desired) level due to the charge sharing operation. Since the charge transfer transistors MCT and MCTB are turned off in the bit line and the complementary bit line BLB, their logic states are kept similar to each other in the second section. 
     In the fourth section (charge transfer section, section t 3 -t 4 ), the transfer gate transistor MP 1  is turned on and the transfer gate transistor MN 1  is turned off. The equalizing signals EQ and PEQ become logic low to turn off the transistors MN 4  and MN 13  in  FIG.  5    and turn on the equalizing transistor MP 13 . In addition, the offset transistor MN 2  and the internal power supply transistor MN 3  are turned off. 
     According to the transistor connection of the fourth section, a transfer gate voltage VTG is supplied to the node N 1  via the transistor MP 1 , and the charge transfer signal CT become logic high according to the voltage level of the node N 1 , thus turning on the charge transistors MCT and MCTB. The charge stored in the sensing bit line and the sensing complementary bit line SBL/SBLB are output to the bit line and the complementary bit line BL/BLB via the charge transfer transistors MCT and MCTB. According to the internal power enable signal Vinta in  FIG.  9   , the first internal power Vinta or the second internal power Vinta 2  is continuously supplied to the LA node. The amount of charge stored in the sensing bit line and the sensing complementary bit line SBL/SBLB is output to the bit line and the complementary bit line BL/BLB after the charge sharing operation. 
     In the fifth section (sensing section, section t 4 -t 5 ), the turn-on/turn-off state of the transfer gate transistor MP 1 , the transfer gate transistor MN 1 , the equalizing transistor MN 4  and the equalizing transistor MN 13  in  FIG.  5   , the offset transistor MN 2  and the internal power supply transistor MN 3  are kept identical to those in the fourth section. However, as the control signals LA/LAB transitions to logic high and logic low, respectively, the P-type amplifiers MP 11  and MP 12  in  FIG.  5    and the N-type amplifiers MN 11  and MN 12  in  FIG.  5    are activated to amplify the amount of charge stored in the sensing bit line and the sensing complementary bit line SBL/SBLB, and the voltage according to the amplified amount of charge is output to the bit line and the complementary bit line BL/BLB. 
     In a sixth section (restore section, section t 5 -t 6 ), when the CTOFF signal maintains logic low and the CTPSB signal changes from logic low to logic high, the transfer gate transistor MP 1  is turned off again, and the transfer gate transistor MN 1  is kept turned off. As the restore bar signal RSTB transitions to logic low, the isolation transistor MP 2  is turned on. The control signals LA/LAB are maintained like the fourth section, and thus the P-type amplifiers MP 11  and MP 12  in  FIG.  5    and the N-type amplifiers MN 11  and MN 12  in  FIG.  5    perform the amplification. As the isolation voltage VISO is supplied to the node N 1 , the charge transfer signal CT becomes logic high, and the charge transfer transistors MCT and MCTB are turned on. 
     The bit line and the complementary bit line BL/BLB may be sensed with the sensing bit line and the sensing complementary bit line SBL/SBLB by the charge transfer transistors MCT and MCTB and may thus be charged with the amplified charge or discharged. 
     Hereinafter, the pre-charging operation is performed again in the section of t 6  to t 8  in  FIG.  9   , and the offset removal operation, the charge sharing operation, the charge transfer operation, the sensing operation, and the restoring operation are sequentially performed again in the section after t 8 . 
       FIG.  13    is a block diagram illustrating a stacked memory device according to some example embodiments. 
     Referring to  FIG.  13   , the stacked memory device  400  may include a buffer die  410  and a plurality of core dies  420  to  450 . For example, the buffer die  410  may be referred to as an interface die, a base die, a logic die or a master die, and each of the core dies  420  to  450  may be referred to as a memory die or a slave die. Even though  FIG.  13    illustrates that four core dies  420  to  450  are included in the stacked memory device  400 , the number of core dies may be variously changed. For example, the stacked memory device  400  may include eight core dies, 12 core dies, or 16 core dies. 
     The buffer die  410  and the core die  420  to  450  may be stacked via silicon penetration electrodes (TSV) and connected electrically to each other. Accordingly, the stacked memory device  400  may have a 3D memory structure in which a plurality of dies  410  to  450  are stacked. For example, the stacked memory device  400  may be implemented based on an HBM or an HMC standard. 
     The stacked memory device  400  may support a plurality of functionally independent channels (or vaults). For example, the stacked memory device  400  may support eight channels CH 0  to CH 7 . When each of the channels CH 0  to CH 7  supports  128  data DQ transfer paths I/O, the stacked memory device  400  may support 1024 data transfer paths. However, the present disclosure is not limited thereto, and the stacked memory device  400  may support 1024 or more data transfer paths and may support eight or more channels (for example, 16 channels). When the stacked memory device  400  supports 16 channels, each of the channels may support 64 data transfer paths. 
     Each of the core dies  420  to  450  may support at least one channel. For example, as illustrated in  FIG.  13   , each of the core dies  420  to  450  may support two channels (CH 0 -CH 2 , CH 1 -CH 3 , CH 4 -CH 6 , and CH 5 -CH 7 ). In this case, the core dies  420  to  450  may support different channels. However, the present disclosure is not limited thereto, and at least two of the core dies  420  to  450  may support the same channel. For example, each of the core dies  420  to  450  may support a first channel CH 0 . 
     Each of the channels may constitute an independent command and a data interface. For example, each channel may be independently clocked based on an independent timing requirement and may not be synchronized with each other. For example, each channel may change a power state or perform a refreshing operation based on the independent command 
     Each of the channels may include a plurality of memory banks  401 . Each of the memory banks  401  may include the memory cells connected to the word lines and the bit lines, a row decoder, a column decoder, and a sense amplifier. For example, each of the channels CH 0  to CH 7  may include eight memory banks  401 . However, the present disclosure is not limited thereto, and each of the channels CH 0  to CH 7  may include eight or more memory banks  401 . Even though  FIG.  13    illustrates that the memory banks included in one channel are included in one core die, the memory banks included in the one channel may be distributed in a plurality of core dies. For example, when each of the core dies  420  to  450  supports the first channel CH 0 , the memory banks included in the first channel CH 0  may be distributed in the core dies  420  to  450 . 
     In some example embodiments, one channel may be divided into two pseudo-channels that operate independently. For example, the pseudo-channels may share commands and clock inputs (e.g., clock signal CK and clock enable signal CK) of a channel but may independently decode and execute the commands For example, when one channel supports 128 data transfer paths, each of the pseudo-channels may support 64 data transfer paths. For example, when one channel supports  64  data transfer paths, each of the pseudo-channels may support 32 data transfer paths. 
     The buffer die  410  and the core dies  420  to  450  may include a TSV region  402 . TSVs configured to penetrate the dies  410  to  450  may be disposed in the TSV region  402 . The buffer die  410  may transmit or receive signals and/or data to or from the core dies  420  to  450  through the TSVs. Each of the core dies  420  to  450  may transmit or receive signals and/or data to or from the buffer die  410  and other core dies through the TSVs. In this case, the signals and/or data may be independently transmitted and received through the TSVs corresponding to each channel For example, when an external host device transmits a command and an address to the first channel CH 0  to access the memory cell of the first core die  420 , the buffer die  410  may transmit control signals to the first core die  420  via the TSVs corresponding to the first channel CH 0  and access the memory cell of the first channel CH 0 . 
     The buffer die  410  and the core dies  420  to  450  may further include a control logic. The control logic may control access to the memory banks  401  based on the command and the address signal supplied from the memory controller ( FIG.  1   ) and may generate control signals for accessing the memory banks  401 . 
     The buffer die  410  and the core die  420  to  450  may include global connection controllers  310  and  310 ′ according to some example embodiments of  FIG.  4  or  11   . The global connection controllers  310  and  310 ′ may be disposed in a peripheral circuit region of a first semiconductor layer  410  according to some example embodiments or may be disposed in a junction region of the first semiconductor layer  410  according to other example embodiments. For example, the internal power supply transistor MN 3  and/or MN 5  may be disposed in a junction region in which the bit line sense amplifier is not disposed, according to some example embodiments. 
     The buffer die  410  may include a physical layer PHY  411 . The physical layer  411  may include interface circuits for communication with the external host device. For example, the physical layer  411  may include interface circuits corresponding to the memory device interface described in  FIG.  1   . The signals and/or data received via the physical layer  411  may be transmitted to the core dies  420  to  450  via the TSVs. 
     In some example embodiments, the buffer die  410  may include a channel controller corresponding to each of the channels. The channel controller may manage memory reference operations of a corresponding channel, and may determine timing requirements of the corresponding channel 
     In some example embodiments, the buffer die  410  may include a plurality of pins for receiving signals from the external host device. The buffer die  410  may receive a clock signal CK, a command/address signal C/A, a write data strobe signal WDQS, and a data signal DQ via the plurality of pins, and may transmit a read data strobe signal RDQS and a data signal DQ. For example, the buffer die  410  may include two pins for receiving the clock signal CK per channel,  14  pins for receiving the command/address signal C/A, eight pins for receiving the write data strobe signal WDQS, eight pins for transmitting the read data strobe signal RDQS, and  128  pins for transmitting or receiving the data signal DQ. 
       FIG.  14    is a diagram illustrating a semiconductor package according to some example embodiments. 
     Referring to  FIG.  14   , the semiconductor package  1000  may include a stacked memory device  1100 , a system-on-chip  1200 , an interposer  1300 , and a package substrate  1400 . The stacked memory device  1100  may include a buffer die  1110  and core dies  1120  to  1150 . The buffer die  1110  may correspond to the buffer die  410  in  FIG.  13   , and each of the core dies  1120  to  1150  may correspond to each of the core dies  420  to  450  in  FIG.  13   . 
     Each of the core dies  1120  to  1150  may include a memory cell array. The buffer die  1110  may include physical layers PHY  1111 , and direct access region DAB  1112 . The physical layer  1111  may be electrically connected to a physical layer  1210  of the system-on-chip  1200  via the interposer  1300 . The stacked memory device  1100  may receive signals from the system-on-chip  1200  via the physical layer  1111  or may transmit signals to the system-on-chip  1200 . The physical layer  1111  may include interface circuits of the buffer die  410  described with reference to  FIG.  13   . 
     The direct access region  1112  may supply an access path capable of testing the stacked memory device  1100  without passing through the system-on-chip  1200 . The direct access region  1112  may include a conductive means (e.g., a port or a pin) capable of directly communicating with the external test device. The test signal and data received via the direct access region  1112  may be transmitted to the core dies  1120  to  1150  via the TSVs. Data read from the core dies  1120  to  1150  for testing of the core dies  1120  to  1150  may be transmitted to the test device via the TSVs and the direct access region  1112 . Accordingly, a direct access test may be performed for the core dies  1120  to  1150 . 
     The buffer die  1110  and the core dies  1120  to  1150  may be electrically connected to each other via TSVs  1101  and bumps  1102 . The buffer die  1110  may receive signals supplied to each channel from the system-on-chip  1200  via bumps  1102  allocated for each channel. For example, the bumps  1102  may be micro bumps. 
     The system-on-chip  1200  may execute applications supported by the semiconductor package  1000  using the stacked memory device  1100 . For example, the system-on-chip  1200  may operate specialized arithmetic operations by including at least one of the processors, including a central processing unit (CPU), an application processor (AP), a graphical processing unit (GPU), a natural processing unit (NPU), a vision processing unit (VPU), an image processor (ISP), and a digital processor (DSP). 
     The system-on-chip  1200  may include the physical layer  1210  and a memory controller  1220 . The physical layer  1210  may include input/output circuits for transmitting or receiving signals to or from the physical layer  1111  of the stacked memory device  1100 . The system-on-chip  1200  may supply various signals to the physical layer  1111  via the physical layer  1210 . The signals supplied to the physical layer  1111  may be transmitted to the core dies  1120  to  1150  via interface circuits and the TSVs  1101  of the physical layer  1111 . 
     The memory controller  1220  may control an overall operation of the stacked memory device  1100 . The memory controller  1220  may transmit signals for controlling the stacked memory device  1100  to the stacked memory device  1100  via the physical layer  1210 . 
     The interposer  1300  may connect the stacked memory device  1100  and the system-on-chip  1200 . The interposer  1300  may make a connection between the physical layer  1111  of the stacked memory device  1100  and the physical layer  1210  of the system-on-chip  1200 , and may supply physical paths formed using conductive materials. Accordingly, the stacked memory device  1100  and the system-on-chip  1200  may be stacked on the interposer  1300  so that they transmit or receive signals to or from each other. 
     Bumps  1103  may be attached to an upper portion of the package substrate  1400 , and solder balls  1104  may be attached to a lower portion thereof. For example, the bumps  1103  may be flip-chip bumps. The interposer  1300  may be stacked on the package substrate  1400  via the bumps  1103 . The semiconductor package  1000  may transmit or receive the signals to or from other external packages or semiconductor devices via the solder balls  1104 . For example, the package substrate  1400  may be a printed circuit board (PCB). 
       FIG.  15    is a diagram illustrating an implemented example of a semiconductor package according to some example embodiments of the present disclosure. 
     Referring to  FIG.  15   , the semiconductor package  2000  may include a plurality of stacked memory devices  2100  and a system-on-chip  2200 . The stacked memory devices  2100  and the system-on-chip  2200  may be stacked on an interposer  2300 , and the interposer  2300  may be stacked on a package substrate  8400 . A semiconductor package  800  may transmit or receive signals to or from other external packages or semiconductor devices via solder balls  2001  attached to a lower portion of the package substrate  8400 . 
     Each of the stacked memory devices  2100  may be implemented based on an HBM standard. However, the present disclosure is not limited thereto, and each of the stacked memory devices  2100  may be implemented based on GDDR, HMC, or a Wide I/O standard. Each of the stacked memory devices  2100  may correspond to the stacked memory device  1000  of  FIG.  14   . 
     The system-on-chip  2200  may include at least one processor such as a CPU, an AP and an NPU, and a plurality of memory controllers for controlling the plurality of stacked memory devices  2100 . The system-on-chip  2200  may transmit or receive the signals to or from a corresponding stacked memory device via the memory controller. The system-on-chip  2200  may correspond to the system-on-chip  1200  in  FIG.  14   . 
       FIG.  16    is a diagram illustrating the semiconductor package according to some example embodiments. 
     Referring to  FIG.  16   , the semiconductor package  3000  may include a stacked memory device  3100 , a host die  3200 , and a package substrate  3300 . The stacked memory device  3100  may include a buffer die  3110  and core dies  3120  to  3150 . The buffer die  3110  may include a physical layer  3111  for communicating with the host die  3200 , and each of the core dies  3120  to  3150  may include a memory cell array. The stacked memory device  3100  may correspond to the stacked memory device  400  in  FIG.  13   . 
     The host die  3200  may include a physical layer  3210  for communicating with the stacked memory device  3100  and a memory controller  3220  for controlling an overall operation of the stacked memory device  3100 . In addition, the host die  3200  may include a processor for controlling the overall operation of the semiconductor package  3000  and executing an application supported by the semiconductor package  3000 . For example, the host die  3200  may include at least one processor such as a CPU, an AP and an NPU. 
     The stacked memory device  3100  may be disposed on the host die  3200  based on TSVs  3001  and may be vertically stacked on the host die  3200 . Accordingly, the buffer die  3110 , the core dies  3120  to  3150 , and the host die  3200  may be electrically connected to each other via the TSVs  3001  and bumps  3002  without the interposer. For example, the bumps  3002  may be micro bumps. 
     Bumps  3003  may be attached to an upper portion of the package substrate  3300 , and solder balls  3004  may be attached to a lower portion thereof. For example, the bumps  3003  may be flip-chip bumps. The host die  3200  may be stacked on the package substrate  3300  via the bumps  3003 . The semiconductor package  3000  may transmit or receive signals to or from other external packages or semiconductor devices via the solder ball  3004 . 
     In another example embodiment, the stacked memory device  3100  may be implemented only with the core dies  3120  to  3150  without the buffer die  3110 . In this case, each of the core dies  3120  to  3250  may include interface circuits for communicating with the host die  3200 . Each of the core dies  3120  to  3250  may transmit or receive signals to or from the host die  3200  via the TSVs  3001 . 
     Although the example embodiments of the present disclosure have been described above with reference to the accompanying drawings, the present disclosure may be embodied in many different forms without changing technical subject matters and essential features as will be understood by those skilled in the art. Therefore, example embodiments set forth herein are examples only and not to be construed as a limitation.