KR102346476B1 - Apparatus for measuring bioimpedance and electrode-side board thereof - Google Patents

Abstract

A bioimpedance measuring device comprising an electrode-side board configured to connect a current electrode in contact with a body, wherein a current source configured to apply a current to the current electrode is included in the electrode-side board, and the electrode-side board is connected via a cable , a bioimpedance measuring device is provided, which is connected to the other board on which a processing circuit unit for processing a signal obtained through the electrode side board and/or a frequency signal generator for providing a predetermined frequency signal to the electrode side board is disposed.

Description

Bioimpedance measuring device and its electrode side board

Embodiments relate to a bioimpedance measuring device, and more particularly, to a configuration of an electrode-side board to which electrodes constituting bioimpedance are connected.

Recently, in order to analyze the state or characteristics of the body including body fat, a bioimpedance measuring device for measuring bioimpedance has been widely used. For example, since there is a difference in water distribution in the muscles and fats of the body, by measuring the body impedance, it is possible to analyze the body water content, muscle mass, and fat mass of a subject in a simple and reliable manner.

The bioimpedance measuring apparatus measures the bioimpedance by contacting an electrode to the body of a subject, applying a predetermined current through the electrode, and measuring the potential difference between the applied current and a path through which the current flows.

The current applied to the body of the subject for measurement of bioimpedance is generated through a current source in response to a multi-frequency signal, is applied to electrodes through a cable, and flows to the subject. A high-frequency component of the current generated by the current source can be radiated when passing through the cable, and further, the magnitude of the current actually applied to the current electrode can be reduced by the radiation and loss of the current through the cable.

That is, since the current actually delivered to the subject and the current generated by the current source are different, when the bioimpedance of the subject is measured by measuring the current generated by the current source, the measured bioimpedance of the subject is lost and radiated current error due to .

Accordingly, there is a need for development of a bioimpedance measuring device capable of accurately measuring a subject's bioimpedance without considering radiation and loss due to a cable of a current generated by a current source.

The information described above is for understanding only, and may include content that does not form a part of the prior art, and may not include what the prior art can present to a person skilled in the art.

KR 2003-0066709 A

Provided is a bioimpedance measuring device capable of minimizing radiation and loss of current applied to the current electrode to the outside by disposing a current source configured to apply a current to the current electrode in contact with the body on the electrode side board.

The other side board (analog board) are connected to each other through a shield cable, thereby providing a bioimpedance measuring device capable of minimizing signal radiation and loss in signal transmission between an electrode-side board and the other board.

A current source configured to apply a current to the current electrode and a current detection circuit unit for detecting a current generated in the current source are disposed on the electrode side board, so that there is no need to consider the radiation and loss of the current applied to the current electrode to the outside. A bioimpedance measuring device capable of measuring bioimpedance is provided.

In one aspect, in the bioimpedance measuring device, at least one electrode in contact with the body is connected, and an electrode side board including a current source configured to apply a current to a current electrode among the at least one electrode A bioimpedance measuring device is provided.

The bioimpedance measuring apparatus may further include a current detection circuit configured to detect a current generated by the current source.

The current detection circuit unit may be disposed on the electrode side board.

The current source may include a driver IC for applying a current.

The current source may generate a current applied to the current electrode in response to a received frequency signal.

The bioimpedance measuring apparatus may further include a relay connected between the current electrode and the current source.

The relay may be configured to open when no current is applied by the current source to the current electrode.

The electrode side board may be connected to the other board on which at least one of a processing circuit unit for processing a signal obtained through the electrode side board and a frequency signal generator for providing a predetermined frequency signal to the electrode side board is disposed. .

The bioimpedance measuring apparatus may further include a transceiver for electrically connecting the electrode-side board and the other board.

At least one of a connection between the processing circuit unit and the electrode-side board and a connection between the frequency signal generator and the electrode-side board may be made through the transceiver.

The bioimpedance measuring apparatus may further include a voltage electrode for contacting the body and measuring a voltage of the body.

A signal obtained through the voltage electrode may be transferred to the other board for processing.

At least one of a connection by the transceiver and a connection between the voltage electrode and the other board may be made through a shield cable.

The bioimpedance measuring apparatus may further include an impedance matching circuit for the shielded cable.

The impedance matching circuit unit may include an active element, a resistor, and a capacitor.

The impedance matching circuit unit may be disposed at both ends of the shielded cable.

The current source configured to apply a current to the current electrode is disposed on the electrode side board rather than the analog board side, so that the current generated by the current source can be applied to the current electrode without loss, and the accuracy of bioimpedance determination through current measurement is improved. A bioimpedance measuring device capable of increasing may be provided.

In the connection between the electrode side board and the analog board, the shielded cable is used as a multi-frequency (multi-frequency) signal application cable, a current sensing signal cable, and a voltage sensing signal cable, so that the signal in the signal transmission between the electrode side board and the other board The radiation and loss of the bio-impedance can be minimized, and thus, a bio-impedance measuring device capable of increasing the accuracy of bio-impedance determination can be provided.

1 is a diagram illustrating a method between a bioimpedance measuring device according to an embodiment and a bioimpedance measuring device having a current source on an analog board when a current is applied to a subject through a current electrode connected to an electrode-side board to measure the bioimpedance; Comparison of current application methods.
2 schematically shows a bioimpedance measuring apparatus according to an exemplary embodiment.
3 illustrates an impedance matching circuit unit included in a bioimpedance measuring apparatus according to an example.
4 shows a cable structure including a shielded cable used in a bioimpedance measuring apparatus according to an example.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Like reference numerals in each figure indicate like elements.

1 is a diagram illustrating a method between a bioimpedance measuring device according to an embodiment and a bioimpedance measuring device having a current source on an analog board when a current is applied to a subject through a current electrode connected to an electrode-side board to measure the bioimpedance; Comparison of current application methods.

1 illustrates a method of applying a current to the body of a subject when measuring the bioimpedance of a subject using a bioimpedance measuring device.

The bioimpedance measuring apparatus may include a current electrode and a voltage electrode, and may include a current source for applying a current to the body through the current electrode. In addition, the bioimpedance measuring apparatus may include a current detecting circuit for detecting (measuring) the current applied by the current source. The bioimpedance measuring apparatus may measure a current applied to the subject's body through the current electrode and a voltage of the subject's body measured by the voltage electrode, and calculate bioimpedance based thereon. For example, the bioimpedance measuring device may apply a high-frequency current generated by a current source from one point on the subject's body to another, and the applied current (current flowing through the body) and two The bioimpedance of the subject may be measured based on measuring the potential difference between the points.

In FIG. 1, <a> shows a current application method of a bioimpedance measuring device in which a current source for applying a current to a subject exists on an analog board. The current generated by the current source was assumed to be _{I(I a} + I _{b ).} The current I is a current generated in response to a multi-frequency signal synthesized with a multi-frequency, and a relatively _{high-frequency current I a and a relatively} It may include a low-frequency current I _{b .} In <a>, the current I generated by the current source is applied to the subject via the cable and the electrode-side board, and the current electrode connected to the electrode-side board. When a current I passes through a cable, a high-frequency current I _a can radiate out of the cable. At this time, the actual current applied to the subject through the electrode-side board and the current electrode connected to the electrode-side board becomes I _b . In addition, by the current radiated and lost through the cable, the magnitude applied to the subject through the current electrode may be reduced. Accordingly, when the bioimpedance measuring apparatus detects the current I and measures the subject's bioimpedance based on this, the measured bioimpedance may include an error due to the radiated (lost) current.

Meanwhile, <b> in FIG. 1 shows a method of applying a current of a bioimpedance measuring apparatus according to an embodiment in which a current source for applying a current to a subject is disposed on an electrode-side board rather than an analog board. The current applied by the current source is I, which can be assumed to be the same as that in <a>. In <b>, the current I generated by the current source is applied to the subject through the current electrode connected to the electrode side board, without passing through the cable. _{Accordingly, loss of the current I a} by the cable as in <a> may not occur, nor may a decrease in the magnitude of the current occur, so that accurate bioimpedance measurement can be achieved. In addition, in the embodiment, by connecting the electrode-side board and the other board through a shielded cable rather than a general cable, the loss of multi-frequency signals input from the analog board to the current source through the shielded cable can also be minimized.

For a bioimpedance measuring device according to an embodiment in which a current source for applying a current to a subject (that is, a current source for applying a current to a current electrode) is disposed on an electrode side board rather than an analog board, see FIGS. 2 to 4 to be described later. It is described in more detail with reference.

2 schematically shows a bioimpedance measuring apparatus according to an exemplary embodiment.

The illustrated bioimpedance measuring apparatus 100 may correspond to the bioimpedance measuring apparatus in which a current source for applying a current to a subject described above with reference to FIG. 1 is disposed on an electrode-side board.

The bioimpedance measuring apparatus 100 includes an electrode-side board 110 configured to connect at least one electrode that is in contact with the body of a subject, and an electrode-side board 110 electrically connected to the electrode-side board 110 (eg, an analog board) ( 120) may be included. The electrode side board 110 and the other side board 120 may be spaced apart from each other as separate devices (that is, the other side board 120 may exist as an external device with respect to the electrode side board 110), and a transceiver device can be electrically connected to each other through

The transmitting/receiving device is a configuration disposed on the electrode electrode side board 110 and/or the other side board 120, and communication (eg, data and transmission/reception of signals). For example, the transmitting/receiving device may be configured to include an antenna for transmitting/receiving a signal as a wireless communication unit. The wireless communication unit of the transceiver may include, for example, a module for implementing wireless communication using a network such as the Internet or a module for implementing wireless communication using a Bluetooth technology, but is not limited thereto. and may be configured to include a module for implementing any type of wireless communication.

Alternatively, the transceiver may be configured to include a cable as a wired communication unit.

1, 2 and 3 to be described later show only an exemplary embodiment in which the transceiver device includes a cable, but as described above, the transceiver device performs wireless communication between the pole electrode side board 110 and the other side board 120. It may include a wireless communication unit that enables it. That is, the cable or shield cable indicating the transceiver in this document may be replaced with a wireless communication unit.

In the case where the transceiver includes a wired communication unit, the electrode side board 110 and the other side board 120 may communicate with each other by being connected through, for example, a cable. The cable may be, for example, a shielded cable or a shielded cable.

In the case where the voltage electrode 150-2 is disposed on the outside of the electrode side board 110, unlike the illustration, the transceiver device connects the voltage electrode 150-2 and the other board 120 with a configuration. can be covered

The bioimpedance measuring apparatus 100 may also include a power supply unit 130 for supplying power to the electrode side board 110 and the other side board 120 . As shown, the power supply unit 130 may be present on both sides of the electrode side board 110 and the other side board 120 , and unlike the illustration, it is present only on either side of the electrode side board 110 or the other side board 120 . Alternatively, the electrode side board 110 and the other side board 120 may be separately present on the outside.

The electrode side board 110 and the other side board 120 may be electronic devices in which electronic circuit elements, modules, and devices may be mounted.

The electrode side board 110 includes at least one current electrode 150-1 and/or at least one voltage electrode 150-2, or the current electrode 150-1 and the voltage electrode 150-2 Connection units 140-1 and 140-2 configured to be connectable may be included. Unlike the illustration, the voltage electrode 150 - 2 and the connection part 140 - 2 for the voltage electrode may be disposed in a board or device other than the electrode side board 110 .

The other side board 120 may include a processing circuit unit 240 for processing a signal obtained through the electrode side board 110 and a frequency signal generating unit 210 for providing a predetermined frequency signal to the electrode side board 110 . can Contrary to the illustration, only one of the processing circuit unit 240 and the frequency signal generating unit 210 to be provided may be disposed on the other board 120 .

The electrode side board 110 may include a current source 220 configured to apply a current to the current electrode 150 - 1 . The current source 220, as a current driver, may be configured to generate a current to be applied to the subject's body through the current electrode 150 - 1 . The current applied to the current electrode 150 - 1 by the current source 220 may be detected and used to determine the subject's bioimpedance. The current source 220 may include a driver integrated circuit (IC) for applying a current. The driver IC for applying a current may be a high output impedance driver.

The current source 220 and the frequency signal generator 210 may be connected to each other through a cable, for example, a shielded cable. For example, as shown, the frequency signal generator 210 may include a frequency signal generator 212 and a multi-frequency synthesizer 214 , and the current source 220 is connected to the multi-frequency synthesizer 214 through a shielded cable. ) can be connected to The frequency signal generator 210 may provide (generate) a predetermined frequency signal.

The current source 220 may generate a current to be applied to the current electrode 150 - 1 in response to a predetermined frequency signal received from the frequency signal generator 210 through the shielded cable. For example, the signal generated by the frequency signal generator 212 may be synthesized as a multi-frequency signal by the multi-frequency synthesizer 214 . The synthesized multi-frequency signal may be input to the current source 220 through a shielded cable as a predetermined frequency signal, and the current source may generate a current to be applied to the current electrode 150-1 in response to the input multi-frequency signal. have.

A current generated by the current source 220 in response to a predetermined frequency signal from the frequency signal generator 210 may have a frequency characteristic of the predetermined frequency signal. For example, the generated current may have multi-frequency characteristics like a predetermined frequency signal.

The electrode-side board 110 may further include a current detection circuit unit 230 configured to detect a current generated by the current source 220 . The current detection circuit unit 230 may generate a signal related to the current based on the detected current from the current source 220 . The current detection circuit unit 230 may be connected to the other board 120 through a cable, for example, a shielded cable, and outputs a result of detecting a current generated by the current source 220 through the shielded cable as a signal associated with the current. It can be transmitted to the other side board (120).

For example, the current detection circuit unit 230 may be connected to the processing circuit unit 240 of the other board 120 through a shielded cable. The processing circuit unit 240 may process a signal related to the current detected by the current detection circuit unit 230, received through the shielded cable. The processing circuit unit 240 may include an analog/digital (A/D) conversion unit 242 . The A/D converter 242 may convert an analog signal associated with the received current detected by the current detection circuit unit 230 into a digital signal. In other words, the processing of the signal associated with the current may include conversion of an analog signal to a digital signal.

The operation of the current detection circuit unit 230 will be described in more detail below. As illustrated, a current sensing resistor 225 may be connected between the current source 220 (driver IC for applying a current) and the current electrode 150 - 1 . For example, the current detection circuit unit 230 may include a differential amplifier, which may be connected to both ends of the current sensing resistor 225 . The current (current signal) flowing through both ends of the current sensing resistor may be amplified by the differential amplifier, and the amplified signal is a signal related to the current applied by the current source 220 and is transmitted to the processing circuit unit 240 for processing can be A high input impedance buffer may be connected to each input terminal of the differential amplifier. The leakage of the current signal to the differential amplifier may be minimized by the high input impedance buffer connected to each input terminal of the differential amplifier.

In addition, the electrode-side board 110 may further include an ESD (Electro Static Discharge) protection circuit 260-1 connected between the current electrode 150-1 and the current source 220. As shown in FIG. The ESD protection circuit 260-1 is an electrostatic protection circuit, and may be designed to have a predetermined capacitance, for example, a capacitance of 1 pF or less. The ESD protection circuit 260-1 may prevent leakage of the current applied by the current source 220 .

In addition, the electrode-side board 110 may further include a relay 270 connected between the current electrode 150 - 1 and the current source 220 . The relay 270 may be disposed between the ESD protection circuit 260-1 and the current electrode 150-1, as shown. The relay 270 may be disposed as close to the current electrode 150 - 1 as possible.

The relay 270 may be configured to open when no current is applied to the current electrode 150 - 1 by the current source 220 . The relay 270 may include a switch that can be controlled in an open state, or may be replaced with such a switch.

For example, when a plurality of current electrodes 150-1 are connected to the electrode-side board 110, a relay 270 may be connected to each of the current electrode 150-1 sides of the electrode-side board 110, A relay disposed on the side of the current electrode 150 - 1 to which no current is applied by the current source 220 among the plurality of current electrodes 150 - 1 may be opened. Accordingly, leakage of current to the current electrode 150 - 1 to which no current is applied by the current source 220 can be prevented.

The relay 270 may be designed to have a predetermined capacitance, for example, a capacitance of 1 pF or less.

As described above, the electrode-side board 110 may be configured such that not only the current electrode 150-1, but also the voltage electrode 150-2 for contacting the body and measuring the voltage of the body is connected. Similarly to the side of the electrode-side board 110 to which the current electrode 150-1 is connected, the ESD protection circuit 260-2 is also disposed on the side of the electrode-side board 110 to which the voltage electrode 150-2 is connected. can As for the ESD protection circuit 260 - 2 , the above-described description of the ESD protection circuit 260-1 may be applied as it is, and a detailed description thereof will be omitted.

A signal acquired (measured) through the voltage electrode 150 - 2 may be transferred to the other board 120 and processed. For example, the signal obtained through the voltage electrode 150 - 2 is connected to the voltage electrode 150 - 2 side of the electrode side board 110 through a shield cable, the circuit processing unit 240 of the other board 120 . can be processed by In addition, the processing circuit unit 240 may include a differential amplifier 246 and an A/D conversion unit 244 , and the signal input from the voltage electrode 150 - 2 to the processing circuit unit 240 through the shielded cable is After being amplified by the differential amplifier 246 , it may be converted into a digital signal by the A/D converter 244 . The A/D conversion unit 244 may have an integrated configuration with the aforementioned A/D conversion unit 242 or may exist as a separate component.

Although not shown, the bioimpedance measuring apparatus 100 may further include a processor that performs an operation to determine the subject's bioimpedance based on the processed signals obtained from the electrode side board 110 . For example, the processor may determine the bioimpedance of the subject based on a current signal and a voltage signal converted into a digital signal by the AD converters 242 and 244 .

In addition, the processor may control components of the bioimpedance measuring apparatus 100 included in the electrode side board 110 and components of the bioimpedance measuring apparatus 100 included in the other board 120 (eg, a relay). behavior, etc.).

The processor, for example, may be disposed on the other side board 120 side, in this case, the control signal for controlling the components of the bioimpedance measuring device 100 included in the electrode side board 110 is a control line not shown. It can be transmitted from the other side board 120 to the components of the electrode side board 110 through.

In addition, the bioimpedance measuring apparatus 100 may further include impedance matching circuit units 250-1 to 250-3 for the shield cable connecting the above-described other side board 120 and the electrode side board 110. . The impedance matching circuit units 250 - 1 to 250 - 3 may include at least one of an active element, a resistor, and a capacitor. The impedance matching circuit units 250-1 to 250-3 may be disposed at at least one end of the shielded cable. The impedance matching circuit units 250-1 to 250-3 may configure a 6:1 impedance matching circuit for a cable (shielded cable) as shown. Each of the impedance matching circuit units 250-1 to 250-3 is made of different elements (or different device value) can be configured. For convenience, it is illustrated in FIG. 2 that the shielded cable is included in the impedance matching circuit units 250-1 to 250-3, but the impedance matching circuit units 250-1 to 250-3 are configured for impedance matching with respect to the shielded cable. Shielded cables are not included.

The impedance matching circuit units 250-1 to 250-3 will be described in more detail with reference to FIG. 3 to be described later.

Since the technical contents described above with reference to FIG. 1 may be applied as they are, a more detailed description will be omitted below.

3 illustrates an impedance matching circuit unit included in a bioimpedance measuring apparatus according to an example.

In FIG. 3 , the impedance matching circuit unit 250-1 for the shielding cable for applying the multi-frequency signal described above with reference to FIG. 2 will be described in more detail.

As shown, the impedance matching circuit unit 250-1 may include, for example, an active element such as an OPAMP, a resistor, and a capacitor, and the impedance matching circuit unit (ie, an active element, a resistor, and a capacitor) is provided at both ends of the shielded cable. can be placed.

An active element constituting the impedance matching circuit unit 250 - 1 may be an OPAMP. In the impedance matching circuit unit 250-1, a resistor and a capacitor may be connected in parallel to each other.

For example, as illustrated, the impedance matching circuit unit 250 - 1 may be configured as a circuit that attenuates the signal amplitude at a ratio of N:1 in order to obtain the same gain with respect to a predetermined frequency signal. Here, N may be 1 or more real numbers.

As shown, the capacitance value of the shielded cable may be assumed to be _{C b .} The signal generated by the frequency signal generator 210 is input to the first OPAMP and output, _{passes through the first impedance matching circuit unit (N*R a} //C _a ), passes through the shield cable (C _b ), and the second It may be input to and output from the second OPAMP through the impedance matching circuit unit R _b //C _{c , and then input to the current source 220 .} In the illustrated example, the first OPAMP and the first impedance matching circuit are disposed at the end of the frequency signal generator 210 side of the shielded cable, and the second OPAMP and the second impedance matching circuit are the current source 220 side end of the shielded cable was placed on The symbol “//” may indicate a parallel connection between devices.

Values of the elements of the first impedance matching circuit and the second impedance matching circuit and the capacitance of the shielded cable may be configured such that _{C b satisfies Equation 1 below.}

For example, the first impedance matching circuit and the second impedance matching circuit may include a circuit in which a capacitor having a relatively large resistance such as 1 MΩ and a relatively small capacitance of 10 pF unit is connected in parallel.

The shielded cable may be a braided cable having a predetermined length.

In general, the capacitance value (C _b ) of the shielded cable is about 70 pF to 100 pF, so it is impossible to transmit a signal of 10 MHz or higher without leakage and attenuation. However, as shown in FIG. 3 , by configuring the impedance matching circuit unit 250 - 1 for the shielding cable, the capacitance of the shielded cable at the signal output terminal can be designed to be less than 20pF. In other words, by arranging a parallel connection circuit of an active element (OPAMP), hundreds of KΩ to several MΩ resistors and a capacitor of less than 20 pF at the input and output terminals of the shield cable, it is possible to output an input signal up to 100 MHz with a 1/6 signal size, , so that the same gain of 1/6 ratio can be obtained in all frequency domains. In addition, since the output load of the OPAMP can be reduced by the device arrangement as described above, the heat generation problem of the OPAMP can be improved.

The description of the above-described impedance matching circuit unit 250-1 is, the impedance matching circuit unit 250-2 for a shielding cable for applying a current sensing signal and an impedance matching circuit unit 250- for a shielding cable for applying a voltage sensing signal 3) can also be applied, so a redundant description will be omitted.

Since the technical contents described above with reference to FIGS. 1 and 2 may be applied as they are, a more detailed description will be omitted below.

4 shows a cable structure including a shielded cable used in a bioimpedance measuring device according to an example.

The illustrated cable structure 400 may correspond to a cable structure including a cable (eg, a shielded cable) used in the bioimpedance measuring apparatus 100 described above with reference to FIGS. 1 to 3 .

As described above, in the bioimpedance measuring apparatus 100 , a shielded cable may be used as a cable for applying a multi-frequency signal, a cable for a current sensing signal, and a cable for a voltage sensing signal. By using the shielded cable, it is possible to prevent EMI (Electro Magnetic Interference) noise (electromagnetic interference noise) from entering the cable side.

In the embodiment, by using a shielded cable not only for cables for current sensing and voltage sensing signals, but also for cables for applying multi-frequency signals, EMI noise from the outside in the application of multi-frequency signals can be blocked, and multi-frequency signals are Radiation out of the cable can also be prevented. In addition, even when a cable spans or crosses a human body or a metal object, a multi-frequency signal may not be radiated or leaked through the cable sheath to the outside.

In one embodiment, a shield cable for a voltage sensing signal, a shield cable for a current sensing signal, a power supply and a control line (a cable that supplies power to the components of the electrode side board 110 and the other side board 120, and transmits a control signal), And the shielded cable for applying a multi-frequency signal may be integrated into one cable 400 as shown in the illustrated structure.

Since the technical contents described above with reference to FIGS. 1 to 3 can be applied as they are, a more detailed description will be omitted below.

The device described above (particularly, the processor of the bioimpedance measuring device) may be implemented as a hardware component, a software component, and/or a combination of the hardware component and the software component. For example, devices and components described in the embodiments may include, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable array (FPA), It may be implemented using one or more general purpose or special purpose computers, such as a programmable logic unit (PLU), microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. A processing device may also access, store, manipulate, process, and generate data in response to execution of the software. For convenience of understanding, although one processing device is sometimes described as being used, one of ordinary skill in the art will recognize that the processing device includes a plurality of processing elements and/or a plurality of types of processing elements. It can be seen that can include For example, the processing device may include a plurality of processors or one processor and one controller. Other processing configurations are also possible, such as parallel processors.

The software executed by the processor to control the operation and/or function of the bioimpedance measuring device of the embodiment may include a computer program, code, instruction, or a combination of one or more thereof. and may configure the processing device to operate as desired, or independently or collectively instruct the processing device to operate as desired. The software and/or data may be any kind of machine, component, physical device, virtual equipment, computer storage medium or apparatus, to be interpreted by or to provide instructions or data to the processing device. can be Software and data may be stored in one or more computer-readable recording media.

As described above, although the embodiments have been described with reference to the limited embodiments and drawings, various modifications and variations are possible from the above description by those skilled in the art. For example, the described techniques are performed in an order different from the described method, and/or the described components of the system, structure, apparatus, circuit, etc. are combined or combined in a different form than the described method, or other components Or substituted or substituted by equivalents may achieve an appropriate result.

Claims (9)

In the bioimpedance measuring device,
At least one electrode in contact with the body is connected, the electrode side comprising a current source configured to apply a current to a current electrode among the at least one electrode, and a current detection circuit unit configured to detect a current between the current source and the current electrode board; and
The other board including a frequency signal generator for providing a multi-frequency signal to the current source through a first shield cable and a processing circuit for processing a signal obtained through the electrode-side board
including,
The processing circuit unit processes a signal that is detected by the current detection circuit unit and associated with a current received through a second shielded cable and a signal obtained through a voltage electrode and received through a third shielded cable,
Bioimpedance measuring device. According to claim 1,
The current source generates a current having a multi-frequency characteristic applied to the current electrode in response to the multi-frequency signal,
Bioimpedance measuring device. According to claim 1,
The current source includes a driver IC for applying a current, a bioimpedance measuring device. According to claim 1,
a relay connected between the current electrode and the current source
further comprising,
The relay is configured to open when no current is applied by the current source to the current electrode. According to claim 1,
The bioimpedance of the body is determined using a result processed by the processing circuit unit,
Bioimpedance measuring device. According to claim 1,
A transceiver for electrically connecting the electrode-side board and the other board
further comprising,
At least one of a connection between the processing circuit unit and the electrode side board and a connection between the frequency signal generator and the electrode side board is made through the transceiver device. According to claim 1,
Further comprising a voltage electrode for contacting the body and measuring the voltage of the body,
The signal obtained through the voltage electrode is transferred to the other board and processed, a bioimpedance measuring device. 8. The method according to claim 6 or 7,
At least one of a connection by the transceiver and a connection between the voltage electrode and the other board is made through a shielded cable. 9. The method of claim 8,
Further comprising an impedance matching circuit for the shielded cable,
The impedance matching circuit unit is disposed at both ends of the shield cable, a bioimpedance measuring device.

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