Abstract:
A data transmitting and receiving apparatus includes a coil configured to transmit and receive data through inductive coupling, where a voltage drop across the coil constitutes a sensing signal. The apparatus further includes an input unit configured to generate transmission data and a replica signal in accordance with an input data signal, the transmission data being supplied to the coil. The apparatus still further includes a replica unit configured to generate a compensation signal in accordance with the replica signal, and an output unit configured to extract reception data from the sensing signal using the compensation signal.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    A claim of priority under 35 USC §119 is made to Korean Patent Application No. 10-2011-0127409, filed on Dec. 1, 2011, the entirety of which is hereby incorporated by reference. 
       BACKGROUND 
       [0002]    The present general inventive concept generally relates to the transmission and reception of data, and more particularly, the invention concept relates to the utilization inductive coupling to transmit and receive data. 
         [0003]    Inductive coupling is utilized as a type of near field contactless communication technology. When compared to other near field contactless communication technologies, such as radiofrequency identification (RFID), inductive coupling advantageously exhibits relatively high transmission rates and low power consumption. 
         [0004]    In addition to contactless communication between separate devices, inductive coupling may be utilized within a device, such as solid-state drive (SSD), where a plurality of integrated circuits (ICs) is stacked in a single package. Here, inductive coupling may be used to realize data communication between the stacked ICs. 
         [0005]    One drawback of conventional inductive coupling techniques is that there are not capable of simultaneously performing interactive communication over a single channel. This is primarily because echo noise generated by inductance is not effectively eliminated during the interactive communication. For example, an integrated circuit that is transmitting data must stop transmission in order to receive data. Accordingly, interactive communication utilizing conventional inductive coupling is performed through timing control, which can narrow the effective bandwidth. 
       SUMMARY 
       [0006]    In an aspect of embodiments of the inventive concept, a data transmitting and receiving apparatus includes a coil configured to transmit and receive data through inductive coupling, where a voltage drop across the coil constitutes a sensing signal. The apparatus further includes an input unit configured to generate transmission data and a replica signal in accordance with an input data signal, the transmission data being supplied to the coil. The apparatus still further includes a replica unit configured to generate a compensation signal in accordance with the replica signal, and an output unit configured to extract reception data from the sensing signal using the compensation signal. 
         [0007]    In another aspect of the inventive concept, a data transmitting and receiving method includes receiving an input data signal, generating a transmission data and a replica signal in accordance with the input data signal, and transmitting the transmission data inductively via an induction coil and receiving reception data inductively via the induction coil, where a voltage drop across the coil constitutes a sensing signal. The method further includes generating a compensation signal in accordance with the replica signal, and extracting the reception data from the sensing signal using the compensation signal. 
         [0008]    In yet another aspect of embodiments of the inventive concept, a solid state drive (SSD) includes a plurality of stacked semiconductor chips, at least one of which is memory chip, where each of the semiconductor chips includes a contactless communication terminal. The contactless communication terminal includes a coil configured to transmit and receive data through inductive coupling, where a voltage drop across the coil constitutes a sensing signal. The terminal further includes an input unit configured to generate transmission data and a replica signal in accordance with an input data signal, the transmission data being supplied to the coil. The terminal still further includes a replica unit configured to generate a compensation signal in accordance with the replica signal, and an output unit configured to extract reception data from the sensing signal using the compensation signal. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    The inventive concept will become more apparent in view of the accompanying drawings and detailed description that follows. The embodiments depicted therein are provided by way of example, not by way of limitation, wherein like reference numerals refer to the same or similar elements. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating aspects of the inventive concept. 
           [0010]      FIG. 1  is a schematic view a data transmitting and receiving apparatus for use in describing the concept of inductive coupling. 
           [0011]      FIG. 2  is a circuit diagram for use in describing data transmission based on inductive coupling. 
           [0012]      FIG. 3  is a block diagram of a data transmitting and receiving apparatus according to an embodiment of the inventive concept. 
           [0013]      FIG. 4  is a block diagram of a first input unit shown in  FIG. 3  according to an embodiment of the inventive concept. 
           [0014]      FIG. 5  is a block diagram of a first replica unit shown in  FIG. 3  according to an embodiment of the inventive concept. 
           [0015]      FIG. 6  is a block diagram of a first output unit shown in  FIG. 3  according to an embodiment of the inventive concept. 
           [0016]      FIG. 7  is a circuit diagram of a data transmitting and receiving apparatus according to another embodiment of the inventive concept. 
           [0017]      FIG. 8  is a circuit diagram of a data transmitting and receiving apparatus according to yet another embodiment of the inventive concept. 
           [0018]      FIG. 9  is a timing diagram of a data transmitting and receiving apparatus according to an embodiment of the inventive concept. 
           [0019]      FIG. 10  is a schematic view of a solid state drive (SSD) according to an embodiment of the inventive concept. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    The advantages and features of the inventive concept and methods of achieving them will be apparent from the following exemplary embodiments that will be described in more detail with reference to the accompanying drawings. It should be noted, however, that the inventive concept is not limited to the following exemplary embodiments, and may be implemented in various forms. Accordingly, the exemplary embodiments are provided only to disclose the inventive concept and let those skilled in the art know the category of the inventive concept. 
         [0021]    In the present specification, the terms “comprise” and/or “comprising” specify existence of shapes, numbers, steps, operations, members, elements, and/or groups thereof, which are referred to, and do not exclude existence or addition of one or more different shapes, numbers, operations, members, elements, and/or groups thereof. Hereinafter, embodiments of the inventive concept will now be described more fully with reference to accompanying drawings. 
         [0022]    Reference is initially made to  FIGS. 1 and 3  for a discussion of transmission by inductive couple generally. 
         [0023]      FIG. 1  illustrates a data transmitting and receiving apparatus  10 . As shown, the apparatus  10  generally includes a first circuit unit  11  and a second circuit unit  12 . 
         [0024]    The first circuit unit  11  and the second circuit unit  12  include a first coil  11   a  and a second coil  12   a , respectively. In  FIG. 1 , the first circuit unit  11  functions as a transmitting circuit and the second circuit  12  functions as a receiving circuit. When transmission data is provided to the first coil  11   a  of the first circuit unit  11 , voltage fluctuation of the first coil  11   a  is transferred to the second coil  12  as an electrical signal by magnetic coupling of the first coil  11   a  and the second coil  12   a . The electrical signal transferred to the second coil  12   a  is output through an output terminal connected to the second coil  12   a . Near field contactless communication performed in this manner is referred to herein as inductive coupling communication. 
         [0025]      FIG. 2  is a circuit diagram generally corresponding to the apparatus shown in  FIG. 1 . Here, the transmission coil  11   a  is connected to a transmission terminal. The receiving coil  12   a  and its parasitic resistors Ra and Rb are connected in series to a receiving terminal. 
         [0026]    In operation, a data transmission current I T  is provided to the transmission coil  11   a . When the transmission current I T  flows through the transmission coil  11   a , a magnetic field around the transmission coil  11   a  is altered. This variation in the magnetic field leads to voltage (or current) fluctuation at the receiving terminal connected to the receiving coil  12   a . A receiving terminal voltage V R  has a close relationship to change over time of the transmission current I T . Accordingly, the transmission current I T  may be detected from the receiving terminal voltage V R . A relationship between the receiving terminal voltage VR and the transmission current IT is shown below. 
         [0000]    
       
         
           
             
               Time 
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                
               domain 
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                 : 
               
                
               
                   
               
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                   V 
                   R 
                 
                  
                 
                   ( 
                   t 
                   ) 
                 
               
             
             = 
             
               M 
                
               
                 
                    
                   
                     
                       I 
                       T 
                     
                      
                     
                       ( 
                       t 
                       ) 
                     
                   
                 
                 
                    
                   t 
                 
               
             
           
         
       
       
         
           
             
               Frequency 
                
               
                   
               
                
               domain 
                
               
                 : 
               
                
               
                   
               
                
               
                 
                   V 
                   R 
                 
                  
                 
                   ( 
                   ω 
                   ) 
                 
               
             
             = 
             
               j 
                
               
                   
               
                
               ω 
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                
               
                 
                   MI 
                   T 
                 
                  
                 
                   ( 
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         [0027]    In these equations, t represents time, ω represents a frequency, and M represents a mutual inductance the transmission coil  11   a  and the receiving coil  12   a . The mathematical relationships represented by these equations are well known in the art and are thus not explained in further detail here. 
         [0028]    Reference is now made to  FIG. 3 , which is a block diagram of a data transmitting and receiving apparatus  100  according to the inventive concept. The data transmitting and receiving apparatus  100  of this example includes a first circuit unit  110  and a second circuit unit  120 . The first and second circuit units  110  and  120  may each function as a transmitting unit and/or a receiving unit. Indeed, as explained below, the first and second circuit units  110  and  120  transmit and receive data at the same time. 
         [0029]    The first circuit unit  110  includes a first input unit  111 , a first replica unit  112 , a first coil  113 , and a first output unit  114 . 
         [0030]    The first input unit  111  provides transmission data I 1  with reference to an input signal Din 1 . In an exemplary embodiment, the transmission data I 1  is a current signal. The first input unit  111  provides a replica signal Rep 1  with reference to the input signal Din 1 . 
         [0031]    The first coil  113  transfers the transmission data I 1  to the second circuit unit  120  through inductive coupling Likewise, the first coil  113  receives a signal I 2  transmitted from the second circuit unit  120 . The transmission data I 1  and the transmitted signal I 2  lead to fluctuation of a voltage at both ends of the first coil  113 , respectively. The voltage at both ends of the first coil  113  is transferred to the first output unit  114  as a sensing signal V 1 . 
         [0032]    The first replica unit  112  generates a compensation signal echo 1  with reference to the replica signal Rep 1 . As will be described later, the replica signal Rep 1  has waveform corresponding to the input signal Din 1 . The compensation signal echo 1  may have another waveform depending on the configuration of the replica unit  112 . 
         [0033]    The output unit  114  removes noise from the sensing signal V 1  with reference to the sensing signal V 1  and the compensation signal echo 1 . Specifically, the first output unit  114  detects a signal I 2  transferred from the sensing signal V 1 . The detected signal I 2  is provided as an output Dout 1 . 
         [0034]    Similar to the first circuit unit  110 , the second circuit unit  120  transmits and receives data through inductive coupling. The configuration and operation of the second circuit unit  120  are substantially identical to those of the first circuit unit  110  and are thus not described in further detail here. 
         [0035]    According to the above-described configuration, transmission and reception of data may be carried out at the same time through one channel formed by magnetic coupling of the first coil  113  and the second coil  123 . Thus, the data transmitting and receiving apparatus  100  exhibits a relatively high data transfer rate and effective bandwidth. 
         [0036]    Reference is made to  FIG. 4 , which is a block diagram showing an embodiment of the first input unit  111  shown in  FIG. 3 . As shown, the first input unit  111  of this example includes a flip-flop  111   a  and a driver  111   b.    
         [0037]    The flip-flop  111   a  buffers an input signal Din 1  and provides the buffered signal as an output. The buffered signal is provided to a first coil  113  through the driver  111   b . The flip-flop  111   a  operates in synchronization with a clock signal CLK 1 . In an exemplary embodiment, the flip-flop  111   a  holds the input signal Din 1  at the rising edge of the clock signal CLK 1 . The flip-flop  111   a  provides the held input signal Din 1  to the next rising edge of the clock signal CLK 1  as an output. An output of the flip-flop  111   a  is provided as a replica signal Rep 1 . 
         [0038]    The driver  111   b  receives the output of the flip-flop  111   a  to provide transmission data I 1  to a first coil  113 . Since current flowing through the first coil  113  cannot change discretely, transmission data I 1  has a slope near the rising or falling edge of the output of the flip-flop  111   a.    
         [0039]    According to the above-described configuration, the first input unit  111  provides the transmission data I 1  to the first coil  113  with reference to the input signal Din 1  and provides the replica signal Rep 1  having a waveform corresponding to the transmission data I 1 . 
         [0040]    Reference is made to  FIG. 5  which is a block diagram of an embodiment of the first replica unit  112  shown in  FIG. 3 . The first replica unit  112  of this example includes a replica driver  112   a  and a compensator  112   b.    
         [0041]    The replica driver  112   a  provides a current signal to the comparator  112   b  with reference to a replica signal Rep 1 . In an exemplary embodiment, the replica driver  112   a  may function as a buffer. Also in an exemplary embodiment, the replica driver  112   a  may amplify or attenuate the replica signal Rep 1  and provide the amplified or attenuated signal to the compensator  112   b.    
         [0042]    The compensator  112   b  receives a current signal from the replica driver  112   a  to provide a compensation signal echo 1 . As will be described later, the compensation signal echo 1  is a signal for removing echo noise included in a sensing signal V 1 . That is, the compensation signal echo 1  is a signal for detecting a signal I 2  transferred from the sensing signal V 1 . Specifically, the sensing signal V 1  indicates a voltage at both ends of a first coil  113 . However, the voltage at both ends of the first coil  113  is changed by a transmission signal (I 1  in  FIG. 1 ) as well as a signal transferred from a second circuit unit  120 . Accordingly, noise caused by the transmission signal I 1  must be removed to detect a signal (I 2  in  FIG. 1 ) transferred from the sensing signal V 2 . As will be described later, the compensation signal echo 1  has a waveform corresponding to the transmission signal I 1 . Thus, the noise caused by the transmission signal I 1  may be removed by subtracting the compensation signal echo 1  from the sensing signal V 1 . The compensation echo 1  and removal of the noise will also be described later 
         [0043]    Reference is made to  FIG. 6 , which is a block diagram of an embodiment of the first output unit  114  shown in  FIG. 3 . The first output unit  114  of this example includes a subtractor  114   a  and a hysteresis comparator  114   b.    
         [0044]    The subtractor  114   a  subtracts a compensation signal echo 1  from a sensing signal V 1  and outputs a result of the subtraction. 
         [0045]    The hysteresis comparator  114   b  provides an output signal with reference to an output of the subtractor  114   a . Specifically, the hysteresis comparator  114   b  removes noise that is not removed by the subtractor  114   a . For achieving this, the hysteresis comparator  114   b  operates in synchronization with an enable signal enable 1 . In an exemplary embodiment, the hysteresis comparator  114   b  holds an output of the subtractor  114   a  at the rising edge of the enable signal enable 1 . In addition, the hysteresis comparator  114   b  provides the held output to the next rising edge of the enable signal enable 1  as an output. 
         [0046]    In an exemplary embodiment, the hysteresis comparator  114   b  does not hold an output of the subtractor  114   a  when the output of the subtractor  114   a  is lower than a first reference value and higher than a second reference value. In this case, the hysteresis comparator  114   b  maintains the previously held output to a new rising edge of the enable signal enable 1 . 
         [0047]    In an exemplary embodiment, the hysteresis comparator  114   b  outputs a logic level HIGH when the output of the subtractor  114   a  is higher than a first reference value. On the other hand, the hysteresis comparator  114   b  outputs a logic level LOW when the output of the subtractor  114   a  is lower than a second reference value. 
         [0048]    According to the above-described configuration, noise may be removed from the sensing signal V 1  and a transferred signal I 2  may be detected. 
         [0049]    Reference is made to  FIG. 7 , which is a circuit diagram of a data transmitting and receiving apparatus  200  according to another embodiment of the inventive concept. The data transmitting and receiving apparatus  200  includes a first terminal and a second terminal. 
         [0050]    The first terminal of this example includes a first coil L 1 , a first flip-flop  210   a , a first driver  220   a , a first replica driver  230   a , a first compensator  240   a , a first subtractor  250   a , and a first hysteresis comparator  260   a.    
         [0051]    Similarly, the second terminal of this example includes a second coil L 2 , a second flip-flop  210   b , a second driver  220   b , a second replica driver  230   b , a second compensator  240   b , a second subtractor  250   b , and a second hysteresis comparator  260   b.    
         [0052]    The first terminal and the second terminal are substantially identical in configuration and operation. Therefore, this embodiment will be described with respect to the first terminal only. 
         [0053]    In this embodiment, a compensation coil L R1  is used as the first compensator  240   a . In an exemplary embodiment, inductances of the compensation coil L R1  and the first coil L 1  may be equal to each other. 
         [0054]    When an input signal Din 1  is received to the first flip-flop  210   a , the first flip-flop  210   a  buffers the input signal Din 1  and outputs the buffered signal. The first flip-flop  210   a  operates in synchronization with a clock signal CLK 1 . The output of the first flip-flop  210   a  is provided to the first driver  220   a  and the first replica driver  230   a.    
         [0055]    The first driver  220   a  outputs transmission data I 1  with reference to the first flip-flop  210   a . The transmission data I 1  may be a current signal. When the transmission data I 1  flows through a coil, the transmission data I 1  is transferred to the second terminal by inductance coupling. 
         [0056]    The first replica driver  230   a  outputs replica current I R1  with reference to the first flip-flop  210   a . The replica current I R1  is provided to the first compensator  240   a . When the replica current I R1  flows through the compensation coil L R1 , a voltage is induced at both ends of the compensation coil L R1  by electromagnetic effect. 
         [0057]    The first subtractor  250   a  receives a voltage at both ends of the first coil L 1  as a sensing signal V 1 . In addition, the first subtractor  250   a  receives the voltage at both ends of the compensation coil L R1  as a compensation signal echo 1 . 
         [0058]    Hereinafter, an operation principle of the first subtractor  250   a  will now be described. First, components of the sensing signal V 1  are analyzed. At this point, the transmission data I 1  flows through the first coil L 1 . Accordingly, the sensing signal V 1  includes a voltage drop caused by the transmission data I 1  and parasitic resistance, and a voltage drop caused by the transmission data I 1  and magnetic inductance of the first coil L 1 . 
         [0059]    The first coil L 1  is coupled with the second coil L 2  by mutual inductance M. Accordingly, the sensing signal V 1  includes voltage drop caused by the current I 2  flowing through the second coil L 2  and the mutual inductance M. 
         [0060]    Next, components of a compensation signal echo 1  are analyzed. The replica current I RI  flows through the compensation coil L RI . Accordingly, the compensation signal echo 1  includes a voltage drop caused by the replica current I R1  and parasitic resistance, and a voltage drop caused by the replica current I R1  and magnetic inductance of the compensation coil L RI . 
         [0061]    Since the compensation coil L RI  is not coupled with the second coil L 2 , the compensation signal echo 1  is not affected by mutual inductance. 
         [0062]    In the meantime, since outputs of the driver  220   a  and the first replica driver  230   a  are identical to each other, their output waveforms are also identical to each other. In an exemplary embodiment, the intensity of the replica current I R1  may be made equal to that of the transmission data I 1  through appropriate scaling. Further, the inductance of the compensation coil L RI  may be set to be equal to that of the first coil L 1 . 
         [0063]    In this case, the compensation signal echo 1  is made identical to a signal except for a component based on the mutual inductance M among the components of the sensing signal V 1 . 
         [0064]    The first subtractor  250   a  subtracts the compensation signal echo 1  from the sensing signal V 1  and outputs a result of the subtraction. According to the above description, the output of the first subtractor  250   a  includes only a voltage drop caused by the current I 2  flowing through the second coil L 2  and the mutual inductance M between the first and second coils L 1  and L 2 . That is, a noise component caused by the transmission data I 1  is removed from the sensing signal V 1 . 
         [0065]    The output of the first subtractor  250   a  is provided to the hysteresis comparator  260   a  to fully restore a signal transferred from the second terminal. 
         [0066]    The first hysteresis comparator  260   a  operates in synchronization with an enable signal enable 1 . The operation of the first hysteresis comparator  260   a  is the same as that of the previously described hysteresis comparator  114   b  of  FIG. 6 ). 
         [0067]    The first hysteresis comparator  260   a  holds an input at the rising edge of the enable signal enable 1 . Thus, the signal transferred from the second terminal may be fully restored. The restored signal is provided as an output signal Dout 1 . 
         [0068]    According to the above-describe configuration, the data transmitting and receiving apparatus  200  may perform interactive data communication through one channel. Thus, the data transmitting and receiving apparatus  200  may realize a relatively high data transfer rate and effective bandwidth. 
         [0069]    Next, there is provided a data transmitting and receiving apparatus in which an inductor of  FIG. 7  is replaced with a lower-cost resistor. 
         [0070]    Reference is made to  FIG. 8 , which is a circuit diagram of a data transmitting and receiving apparatus  300  according to still another embodiment of the inventive concept. The data transmitting and receiving apparatus  300  includes a first terminal and a second terminal. 
         [0071]    The first terminal of this example includes a first coil L 1 , a first flip-flop  310   a , a first driver  320   a , a first replica driver  330   a , a first compensator  340   a , a first subtractor  350   a , and a first hysteresis comparator  360   a.    
         [0072]    Similarly, the second terminal of this example includes a second coil L 2 , a second flip-flop  310   b , a second driver  320   b , a second replica driver  330   b , a second compensator  340   b , a second subtractor  350   b , and a second hysteresis comparator  360   b.    
         [0073]    The first terminal and the second terminal are substantially identical in configuration and operation. Therefore, this embodiment will be described with respect to the first terminal only. 
         [0074]    In this embodiment, a compensator resistor R 1  is used as the first compensator  340   a.    
         [0075]    When the input signal Din 1  is received to the first flip-flop  310   a , the first flip-flop  310   a  buffers the input signal Din 1  and outputs the buffered signal. The first flip-flop  310   a  operates in synchronization with a clock signal CLK 1 . The output of the first flip-flop  310   a  is provided to the first driver  320   a  and the first replica driver  330   a.    
         [0076]    The first driver  320   a  outputs transmission data I 1  with reference to the first flip-flop  310   a . The transmission data I 1  may be a current signal. When the transmission data I 1  flows through a coil, the transmission data I 1  is transmitted to the second terminal by inductance coupling. 
         [0077]    The first replica driver  330   a  outputs replica current I R1  with reference to the first flip-flop  310   a . The replica current I R1  is provided to the first compensator  340   a . When the replica current I R1  flows through the compensation resistor R 1 , a voltage drop occurs at both ends of the compensation resistor R 1 . 
         [0078]    The subtractor  350   a  receives a voltage at both ends of the first coil L 1  as a sensing signal V 1 . In addition, the first subtractor  350   a  receives a voltage at both ends of the compensation resistor R 1  as a compensation signal echo 1 . 
         [0079]    Hereinafter, an operation principle of the first subtractor  350   a  will now be described. First, components of the sensing signal V 1  are analyzed. At this point, the transmission data I 1  flows through the first coil L 1 . Accordingly, the sensing signal V 1  includes a voltage drop caused by the transmission data I 1  and parasitic resistance, and a voltage drop caused by the transmission data I 1  and magnetic inductance of the first coil L 1 . 
         [0080]    The first coil L 1  is coupled with the second coil L 2  by mutual inductance M. Accordingly, the sensing signal V 1  includes a voltage drop caused by the current I 2  flowing through the second coil L 2  and the mutual inductance M. 
         [0081]    Next, components of a compensation signal echo  1  are analyzed. The replica current I RI  flows through the compensation coil L RI . Accordingly, the compensation signal echo 1  includes voltage drop (I R1 ×R 1 ) caused by the replica current I R1  and the compensation resistor R 1 . 
         [0082]    A waveform of the compensation signal echo 1  may be identical to that of a voltage drop caused by a parasitic resistor of the first coil L 1  through appropriate scaling. The compensation signal echo 1  is subtracted from the sensing signal V 1 . Accordingly, among the components of the sensing signal V 1 , a component of voltage drop caused by the transmission data I 1  and the parasitic resistor may be removed. 
         [0083]    However, although the above procedure is carried out, the sensing signal V 1  includes noise caused by the magnetic inductance of the first coil L 1 . The transmission data I 1  of the first terminal and data I 2  transmitted from the second terminal have a phase difference of 180 degrees to remove the nose caused by the magnetic inductance of the first coil L 1 . 
         [0084]    This may be achieved through phase shift of clocks of the first flip-flop  310   a  and the second flip-flop  310   b . That is, through the clock phase shift, an output of the first flip-flop  310   a  is phase-shifted by +90 degrees and an output of the second flip-flop  310   b  is phase-shifted by −90 degrees. As a result, the transmitted data I 1  and I 2  have a relative phase shift of 180 degrees. 
         [0085]    When the transmitted data I 1  and I 2  have the relative phase shift of 180 degrees, noise caused by magnetic inductance may be removed. This is because the noise caused by magnetic inductance appears only at the rising edge of the first flip-flop  310   a . In contrast, the data I 2  transmitted from the second terminal appears only at the falling edge of the first flip-flop  310   a.    
         [0086]    Accordingly, among the components of the sensing signal V 1 , if only a component appearing at the falling edge of the first flip-flop  310   a  is output, the noise caused by magnetic inductance is removed. A more detailed description associated with this will be presented later with reference to  FIG. 9 . 
         [0087]    The first subtractor  350   a  subtracts the compensation signal echo 1  from the sensing signal V 1  and outputs a result of the subtraction. According to the above description, the output of the first subtractor  350   a  includes only a voltage drop caused by magnetic inductance L 1  of the first coil L 1  and mutual inductance M of the first and second coils. That is, a component of the noise caused by a parasitic resistor of the first coil is removed from the sensing signal V 1 . 
         [0088]    The output of the first subtractor  350   a  is provided to the first hysteresis comparator  360   a  to fully restore a signal transferred from the second terminal. 
         [0089]    The first hysteresis comparator  360   a  operates in synchronization with the enable signal enable 1 . The operation of the first hysteresis comparator  360   a  is the same as that of the previously described hysteresis comparator  114   b  shown in  FIG. 6 . 
         [0090]    The enable signal enable 1  has a phase difference of 180 degrees with respect to a clock CLK 1  of the first flip-flop  310   a . The first hysteresis comparator  360   a  holds an input at the rising edge of the enable signal enable 1 . Thus, the noise caused by the magnetic inductance L 1  may be removed and the signal transferred from the second terminal may be fully restored. The restored signal is provided as an output signal Dout 1 . 
         [0091]    According to the above configuration, the data transmitting and receiving apparatus  300  may simultaneously perform interactive data communication through one channel. Thus, the data transmitting and receiving apparatus  300  may realize a relatively high data transfer rate and effective bandwidth. 
         [0092]    Reference is made to  FIG. 9 , which is an exemplary operational timing diagram of the data transmitting and receiving apparatus shown in  FIG. 8 . Hereinafter, the operation of the apparatus of  FIG. 8  will be further described with reference to  FIGS. 8 and 9 . 
         [0093]    In this embodiment, a clock CLK 1  of a first flip-flop  310   a  and a clock CLK 2  of a second flip-flop  310   b  have a phase difference of 180 degrees with respect to each other. As a result, a signal I 2  received to a first coil L 1  from a second terminal (hereinafter referred to as “receiving data I 2 ”) and transmitted data I 1  have a phase difference of 180 degrees with respect to each other. 
         [0094]    A component based on a parasitic resistor of a first coil (I 1 *Rx), a component based on magnetic inductance of the first coil (L 1 *(dI 1 /dt)), and a component based on mutual inductance (M*(dI 2 /dt)) are all added to the sensing signal V 1 . The component based on mutual inductance (L 1 *(dI 1 /dt)) appears at the rising edge of the clock CLK 1 . To the contrary, the component based on mutual inductance (M*(dI 2 /dt)) appears at the falling edge of the clock CLK 1  because the transmission data I 2  has a phase difference of 180 degrees. 
         [0095]    Since the compensation signal echo 1  includes only a component of voltage drop caused by a resistor, the compensation signal echo 1  has the same waveform as the component based on a parasitic resistor of a first coil (I 1 *Rx). Through appropriate scaling, the compensation signal echo 1  may be set to the intensity equivalent to the component (I 1 *Rx). 
         [0096]    A signal data 1  is an output of the first subtractor  350   a . The signal data 1  appears as a result of subtracting the compensation signal echo 1  from the sensing signal V 1 . The signal data 1  is provided to the first hysteresis comparator  360   a.    
         [0097]    The first hysteresis comparator  360   a  removes the component based on magnetic inductance of the first coil (L 1 *(dI 1 /dt)) among components included in the signal data 1 . The component removal may be achieved by making the enable signal enable 1  have a phase difference of 180 degrees with respect to the clock CLK 1 . This is because the transmission data I 1  appears at the rising edge of the clock CLK 1  and the receiving data I 2  appears at the falling edge of the clock CLK 2 . 
         [0098]    An output of the first hysteresis comparator  360   a  is provided as an output signal Dout 1 . It may be confirmed that the output signal Dout 1  is a noise-removed signal and a fully restored version of the second terminal input signal Din 2 . 
         [0099]    According to the above configuration, the data transmitting and receiving apparatus  300  may simultaneously perform interactive data communication through one channel. Thus, the data transmitting and receiving apparatus  300  may realize a relatively high data transfer rate and effective bandwidth. 
         [0100]    Reference is now made to  FIG. 10 , which illustrates a solid state drive (SSD) according to an embodiment of the inventive concept. 
         [0101]    The SSD  1000  of this example includes a plurality of stacked semiconductor chips  1010 . The semiconductor chips  1010  may include multiple NAND flash memory chips or the like, and one or more semiconductor chips  1010  may be a memory controller. In this embodiment each of the semiconductor memory chips includes a contactless communication terminal circuit  1010   a  which is in accordance with one or more of the embodiments described above in connection with  FIGS. 3-9 , thereby allowing interactive data communication among the semiconductor chips  1010 . Also shown in  FIG. 10  are wirings for supplying power to the semiconductor chips  1010 , although it is well understood that other known techniques for supplying power may be adopted. 
         [0102]    While the inventive concept has been particularly shown and described with reference to exemplary embodiments thereof, it will be apparent to those of ordinary skill in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the inventive concept as defined by the following claims.