Sixteen-electrode biological impedance test circuit and body fat scale
By optimizing the measurement circuit through the sixteen-electrode bioimpedance test circuit, the signal attenuation and data fluctuation problems of the eight-electrode body fat scale are solved, accurate and stable testing of trunk impedance is achieved, and the measurement accuracy of the body fat scale is improved.
Patent Information
- Application Number
- CN202422081195.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-26
- Publication Date
- 2025-09-23
- Estimated Expiration
- 2034-08-26
AI Technical Summary
Existing eight-electrode body fat scales suffer from signal attenuation due to the long measurement circuit, which affects the accuracy and precision of the measurement data. They cannot directly measure trunk impedance, and the conversion of multiple measurement paths causes data fluctuations.
A sixteen-electrode bioimpedance test circuit is used, including a power supply circuit, a main control circuit, a current excitation circuit, a voltage sampling circuit, a channel switching circuit, and an electrode assembly. The measurement circuit is optimized to directly test the trunk impedance, reduce signal attenuation, and improve data accuracy and stability.
Through a new testing method, signal attenuation is reduced, the accuracy and stability of test data are improved, data fluctuations are avoided, and accurate and stable testing of torso impedance is achieved.
Smart Images
Figure CN223365537U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of body fat scales, in particular to a sixteen-electrode bioimpedance test circuit and a body fat scale. Background Art
[0002] An eight-electrode body fat scale uses eight electrodes to perform body impedance testing. The basic principle of the test is to perform impedance testing through left and right hand circuits, left and right foot circuits, left hand and left foot circuits, left hand and right foot circuits, right hand and right foot circuits, and right hand and left foot circuits. However, this circuit test results in attenuation of the test signal due to the long measurement circuit, which affects the accuracy and precision of the measurement data. At the same time, due to measurement path problems, TR (trunk impedance) cannot be directly measured. Therefore, the TR (trunk impedance) in existing body fat scales is usually obtained by converting multiple sets of measurement paths, further affecting the measurement accuracy. Therefore, a sixteen-electrode bioimpedance test circuit and a body fat scale are urgently needed to solve the above problems. Utility Model Content
[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model provides a sixteen-electrode bioimpedance test circuit and a body fat scale.
[0004] An embodiment of the present invention solves the technical problem by adopting a technical solution: a sixteen-electrode bioimpedance test circuit, comprising a power supply circuit and a main control circuit connected to the power supply circuit, a current excitation circuit, a voltage sampling circuit, a channel switching circuit, and an electrode assembly;
[0005] The power circuit is connected to an external power supply;
[0006] The main control circuit is connected to the input end of the current excitation circuit, the input end of the voltage sampling circuit and the input end of the channel switching circuit respectively. The current excitation circuit is used to apply an excitation current to the measurement object, and the voltage sampling circuit is used to collect the excitation voltage on the measurement object.
[0007] The output end of the channel switching circuit is respectively connected to the output end of the current excitation circuit, the output end of the voltage sampling circuit and the electrode assembly;
[0008] The electrode assembly includes a left hand voltage sampling electrode, a right hand voltage sampling electrode, a left foot voltage sampling electrode, a right foot voltage sampling electrode, a left hand current excitation electrode, a right hand current excitation electrode, a left foot current excitation electrode, a right foot current excitation electrode, a left chest voltage sampling electrode, a right chest voltage sampling electrode, a left abdomen voltage sampling electrode, a right abdomen voltage sampling electrode, a left chest current excitation electrode, a right chest current excitation electrode, a left abdomen current excitation electrode, and a right abdomen current excitation electrode.
[0009] As one of the preferred embodiments of the present invention, the channel switching circuit includes a first analog switch chip U12, a second analog switch chip U13, a third analog switch chip U14 and a fourth analog switch chip U15;
[0010] The first analog switch chip U12 is respectively connected to the main control circuit, the output end of the current excitation circuit, the left hand current excitation electrode, the right hand current excitation electrode, the left foot current excitation electrode, the right foot current excitation electrode, the left chest current excitation electrode, the right chest current excitation electrode, the left abdomen current excitation electrode, and the right abdomen current excitation electrode;
[0011] The second analog switch chip U13 is respectively connected to the main control circuit, the output end of the current excitation circuit, the left chest current excitation electrode, the right chest current excitation electrode, the left abdomen current excitation electrode, and the right abdomen current excitation electrode;
[0012] The third analog switch chip U14 is respectively connected to the main control circuit, the output end of the voltage sampling circuit, the left hand voltage sampling electrode, the right hand voltage sampling electrode, the left foot voltage sampling electrode, the right foot voltage sampling electrode, the left chest voltage sampling electrode, the right chest voltage sampling electrode, the left abdomen voltage sampling electrode, and the right abdomen voltage sampling electrode;
[0013] The fourth analog switch chip U15 is respectively connected to the main control circuit, the output end of the voltage sampling circuit, the left chest voltage sampling electrode, the right chest voltage sampling electrode, the left abdomen voltage sampling electrode, and the right abdomen voltage sampling electrode.
[0014] As one of the preferred embodiments of the present invention, a sixteen-electrode bioimpedance test circuit further includes a weight detection circuit connected to the power supply circuit and the main control circuit respectively, for detecting the weight of the measured object.
[0015] As one of the preferred embodiments of the present utility model, a sixteen-electrode bioimpedance testing circuit further includes a calibration circuit connected to the channel switching circuit for calibrating impedance parameters.
[0016] As one of the preferred embodiments of the present invention, the calibration circuit includes resistors R125-R127, one end of the resistor R125 is connected to the channel switching circuit, the other end of the resistor R125 is respectively connected to one end of the resistor R126 and the channel switching circuit, the other end of the resistor R126 is connected to the channel switching circuit and one end of the resistor R127, and the other end of the resistor R127 is connected to the channel switching circuit.
[0017] As one of the preferred embodiments of the present invention, a sixteen-electrode bioimpedance testing circuit further includes a filter circuit connected between the electrode assembly and the channel switching circuit.
[0018] As one of the preferred embodiments of the present invention, a sixteen-electrode bioimpedance testing circuit also includes a signal amplification circuit connected between the left hand voltage sampling electrode, the right hand voltage sampling electrode, the left foot voltage sampling electrode, the right foot voltage sampling electrode, the left chest voltage sampling electrode, the right chest voltage sampling electrode, the left abdomen voltage sampling electrode, and the right abdomen voltage sampling electrode and the channel switching circuit.
[0019] A body fat scale comprises the bioimpedance testing circuit.
[0020] The beneficial effects of the present invention are as follows: a sixteen-electrode bio-impedance test circuit and a body fat scale, the impedance test circuit including a power supply circuit and a main control circuit, a current excitation circuit, a voltage sampling circuit, a channel switching circuit and an electrode assembly connected to the power supply circuit; the power supply circuit is connected to an external power supply; the main control circuit is respectively connected to the input end of the current excitation circuit, the input end of the voltage sampling circuit and the input end of the channel switching circuit, the current excitation circuit is used to apply an excitation current to the measurement object, and the voltage sampling circuit is used to collect the excitation voltage on the measurement object; the output end of the channel switching circuit is respectively connected to the output end of the current excitation circuit, the output end of the voltage sampling circuit and the electrode assembly, and the electrode assembly includes sixteen electrode assemblies; through a new testing method and optimized measurement loop, the signal attenuation problem is reduced, the accuracy and stability of the test data are improved, and at the same time, the trunk impedance can be directly tested accurately and stably, avoiding the data fluctuation problem caused by the conversion of multiple groups of measurement paths. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments in conjunction with the following drawings, in which:
[0022] Figure 1 This is a principle block diagram of a sixteen-electrode bioimpedance test circuit;
[0023] Figure 2 A circuit diagram of the main control circuit;
[0024] Figure 3 is the circuit diagram of the current excitation circuit;
[0025] Figure 4 is a circuit diagram of a voltage sampling circuit;
[0026] Figure 5 This is the circuit diagram of the first part of the voltage sampling circuit;
[0027] Figure 6 This is the circuit diagram of the second part of the voltage sampling circuit;
[0028] Figure 7 This is the circuit diagram of the third part of the voltage sampling circuit;
[0029] Figure 8 A circuit diagram for a switching circuit;
[0030] Figure 9 A circuit diagram of the calibration circuit;
[0031] Figure 10 The first part of a circuit diagram of a sixteen-electrode bioimpedance test circuit is shown;
[0032] Figure 11 The second part of the circuit diagram of a sixteen-electrode bioimpedance test circuit is shown;
[0033] Figure 12 is a circuit diagram of a signal amplifying circuit;
[0034] Figure 13 This is the distribution diagram of sixteen electrodes. DETAILED DESCRIPTION
[0035] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.
[0036] In the description of this utility model, "above," "below," and "within" are understood to be exclusive of the number indicated, while "above," "below," and "within" are understood to be inclusive of the number indicated. The use of "first" and "second" is solely for the purpose of distinguishing technical features and is not to be construed as indicating or implying relative importance, or implicitly specifying the number or order of the technical features indicated.
[0037] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.
[0038] In this utility model, unless otherwise expressly defined, terms such as "disposed," "installed," and "connected" should be interpreted broadly. For example, they may refer to direct connection or indirect connection through an intermediate medium; fixed connection or detachable connection or integral molding; mechanical connection; internal communication between two components or interaction between two components. Those skilled in the art can reasonably determine the specific meanings of these terms in this utility model based on the specific content of the technical solution.
[0039] Reference Figures 1 to 13 A sixteen-electrode bioimpedance test circuit includes a power supply circuit and a main control circuit 100 connected to the power supply circuit, a current excitation circuit 200, a voltage sampling circuit 300, a channel switching circuit 400, and an electrode assembly 500;
[0040] The power circuit is connected to an external power supply;
[0041] The main control circuit 100 is connected to the input end of the current excitation circuit 200, the input end of the voltage sampling circuit 300, and the input end of the channel switching circuit 400 respectively. The current excitation circuit 200 is used to apply an excitation current to the measurement object, and the voltage sampling circuit 300 is used to collect the excitation voltage on the measurement object;
[0042] The output end of the channel switching circuit 400 is connected to the output end of the current excitation circuit 200 , the output end of the voltage sampling circuit 300 , and the electrode assembly 500 , respectively.
[0043] In this utility model, the working principle is as follows:
[0044] 1) Reference Figure 13 , is a schematic diagram of the distribution of the electrode assembly 500 on the measurement object. Specifically, the electrode assembly 500 includes a left-hand voltage sampling electrode 501 (HVL), a right-hand voltage sampling electrode 502 (HVR), a left-foot voltage sampling electrode 503 (FVL), a right-foot voltage sampling electrode 504 (FVR), a left-hand current excitation electrode 505 (HIL), a right-hand current excitation electrode 506 (HIR), a left-foot current excitation electrode 507 (FIL), a right-foot current excitation electrode 508 (FIR), a left-chest voltage sampling electrode 509 (CVL), a right-chest voltage sampling electrode 510 (CVR), a left-abdomen voltage sampling electrode 511 (AVL), a right-abdomen voltage sampling electrode 512 (AVR), a left-chest current excitation electrode 513 (CIL), a right-chest current excitation electrode 514 (CIR), a left-abdomen current excitation electrode 515 (AIL), and a right-abdomen current excitation electrode 516 (AIR).
[0045] 2) The power supply circuit is connected to an external power supply to provide operating voltage and operating current for the subsequent circuits. The main control circuit 100 sends 20kHz and 100kHz square wave signals to the current excitation circuit 200 to generate corresponding 20kHz and 100kHz sine wave signals. The main control circuit 100 realizes the body circuit test by controlling the on and off of each channel in the channel switching circuit 400, and performs LA (left hand impedance), RA (right hand impedance), TR (trunk impedance), LF (left foot impedance), and RF (right foot impedance) impedance tests; the voltage sampling circuit 300 sends the impedance ADC collected by the test to the main control circuit 100 for calculation and processing. Combined with the weight parameters of the measured object collected by the weight detection circuit 600, the body fat parameters of the measured object can be calculated.
[0046] 3) Reference Figure 8 、 10 -12. In one embodiment, the channel switching circuit 400 includes a first analog switch chip U12, a second analog switch chip U13, a third analog switch chip U14, and a fourth analog switch chip U15; the first analog switch chip U12 is respectively connected to the main control circuit 100, the output end of the current excitation circuit 200, the left hand current excitation electrode 505, the right hand current excitation electrode 506, the left foot current excitation electrode 507, the right foot current excitation electrode 508, the left chest current excitation electrode 513, the right chest current excitation electrode 514, the left abdomen current excitation electrode 515, and the right abdomen current excitation electrode 516; the second analog switch chip U13 is respectively connected to the main control circuit 100, the output end of the current excitation circuit 200, the left chest current excitation electrode 513, the right chest current excitation electrode The third analog switch chip U14 is respectively connected to the main control circuit 100, the output end of the voltage sampling circuit 300, the left hand voltage sampling electrode 501, the right hand voltage sampling electrode 502, the left foot voltage sampling electrode 503, the right foot voltage sampling electrode 504, the left chest voltage sampling electrode 509, the right chest voltage sampling electrode 510, the left abdomen voltage sampling electrode 511 and the right abdomen voltage sampling electrode 512; the fourth analog switch chip U15 is respectively connected to the main control circuit 100, the output end of the voltage sampling circuit 300, the left chest voltage sampling electrode 509, the right chest voltage sampling electrode 510, the left abdomen voltage sampling electrode 511 and the right abdomen voltage sampling electrode 512. 4)
[0048] Table 1
[0049]
[0050] ① Refer to Table 1, LA impedance loop test is as follows:
[0051] Analog switch logic control: U12-000, U14-000
[0052] Current test path: HIL--CIL
[0053] Voltage detection point: HVL1--CVL1
[0054] ② Refer to Table 1, RA impedance loop test is as follows:
[0055] Analog switch logic control: U12-001, U14-001
[0056] Current test path: HIR--CIR
[0057] Voltage detection point: HVR1--CVR1
[0058] ③ Refer to Table 1, LF impedance loop test is as follows:
[0059] Analog switch logic control: U12--010, U14--010
[0060] Current test path: AIL--FIL
[0061] Voltage detection point: AVL1--FVL1
[0062] ④ Refer to Table 1, and the RF impedance loop test is as follows:
[0063] Analog switch logic control: U12--011, U14--011
[0064] Current test path: AIR--FIR
[0065] Voltage detection point: AVR1--FVR1 5)
[0067] Table 2
[0068]
[0069] Referring to Table 2, the TR impedance loop test is as follows:
[0070] Analog switch logic control: U13--000, U15--000
[0071] Current test path 1: AIL1--CIR
[0072] Voltage detection point 1: AVL1--CVR1
[0073] Current test path 2: AIR1--CIL
[0074] Voltage detection point 2: AVR1--CVL1
[0075] 6) In one embodiment, a sixteen-electrode bioimpedance test circuit further includes a calibration circuit 700 connected to the channel switching circuit 400 for calibrating impedance parameters. As a preferred embodiment of the calibration circuit 700, the calibration circuit 700 includes resistors R125-R127. One end of the resistor R125 is connected to the channel switching circuit 400. The other end of the resistor R125 is respectively connected to one end of the resistor R126 and the channel switching circuit 400. The other end of the resistor R126 is connected to the channel switching circuit 400 and one end of the resistor R127. The other end of the resistor R127 is connected to the channel switching circuit 400. Specifically, referring to Table 2, the BIA calibration loop test is as follows:
[0076] Analog switch logic control: U13--011, U15--011
[0077] Current test path: U13-11--U13-4
[0078] Voltage detection point: U15-11--U15-4
[0079] 7) The impedance of each circuit can be calculated by measuring the voltage and applied current obtained from each circuit. The TR impedance is composed of the average of two cross-sectional data sets, namely path 1 and path 2, to obtain the complete human body impedance parameters. Combined with the body weight parameters, the human body fat parameters can be obtained. The advantages of this utility model are: through a new testing method and optimized measurement circuits, signal attenuation is reduced, the accuracy and stability of the test data are improved, and the torso impedance can be directly and accurately and stably measured, avoiding the data fluctuation caused by the conversion of multiple measurement paths.
[0080] In one embodiment, the sixteen-electrode bioimpedance test circuit further includes a weight detection circuit 600 connected to the power supply circuit and the main control circuit 100 respectively, for detecting the weight of the measured object.
[0081] In one embodiment, the sixteen-electrode bioimpedance testing circuit further includes a filter circuit 800 connected between the electrode assembly 500 and the channel switching circuit 400 .
[0082] In one embodiment, a sixteen-electrode bioimpedance testing circuit further includes a signal amplification circuit 900 connected between the left hand voltage sampling electrode 501, the right hand voltage sampling electrode 502, the left foot voltage sampling electrode 503, the right foot voltage sampling electrode 504, the left chest voltage sampling electrode 509, the right chest voltage sampling electrode 510, the left abdomen voltage sampling electrode 511, the right abdomen voltage sampling electrode 512 and the channel switching circuit 400; the signal amplification circuit 900 is used to amplify the collected weak voltage parameters and transmit them back to the main control circuit 100.
[0083] A body fat scale comprises the bioimpedance testing circuit.
[0084] Of course, the present invention is not limited to the above-mentioned embodiments. Those skilled in the art may make equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications and substitutions are all within the scope defined by the claims of this application.
Claims
1. A sixteen-electrode bioimpedance test circuit, characterized in that: It comprises a power supply circuit, a main control circuit (100) connected to the power supply circuit, a current excitation circuit (200), a voltage sampling circuit (300), a channel switching circuit (400), and an electrode assembly (500); The power supply circuit is connected to an external power supply; The main control circuit (100) is respectively connected to an input end of the current excitation circuit (200), an input end of the voltage sampling circuit (300), and an input end of the channel switching circuit (400); the current excitation circuit (200) is used to apply an excitation current to a measurement object; and the voltage sampling circuit (300) is used to collect an excitation voltage on the measurement object. The output end of the channel switching circuit (400) is respectively connected to the output end of the current excitation circuit (200), the output end of the voltage sampling circuit (300), and the electrode assembly (500); The electrode assembly (500) includes a left-hand voltage sampling electrode (501), a right-hand voltage sampling electrode (502), a left-foot voltage sampling electrode (503), a right-foot voltage sampling electrode (504), a left-hand current excitation electrode (505), a right-hand current excitation electrode (506), a left-foot current excitation electrode (507), a right-foot current excitation electrode (508), a left-chest voltage sampling electrode (509), a right-chest voltage sampling electrode (510), a left-abdomen voltage sampling electrode (511), a right-abdomen voltage sampling electrode (512), a left-chest current excitation electrode (513), a right-chest current excitation electrode (514), a left-abdomen current excitation electrode (515), and a right-abdomen current excitation electrode (516).
2. The sixteen-electrode bioimpedance test circuit according to claim 1, characterized in that: The channel switching circuit (400) comprises a first analog switch chip U12, a second analog switch chip U13, a third analog switch chip U14 and a fourth analog switch chip U15; The first analog switch chip U12 is respectively connected to the main control circuit (100), the output end of the current excitation circuit (200), the left-hand current excitation electrode (505), the right-hand current excitation electrode (506), the left-foot current excitation electrode (507), the right-foot current excitation electrode (508), the left-chest current excitation electrode (513), the right-chest current excitation electrode (514), the left-abdomen current excitation electrode (515), and the right-abdomen current excitation electrode (516); The second analog switch chip U13 is respectively connected to the main control circuit (100), the output end of the current excitation circuit (200), the left chest current excitation electrode (513), the right chest current excitation electrode (514), the left abdomen current excitation electrode (515), and the right abdomen current excitation electrode (516); The third analog switch chip U14 is respectively connected to the main control circuit (100), the output end of the voltage sampling circuit (300), the left hand voltage sampling electrode (501), the right hand voltage sampling electrode (502), the left foot voltage sampling electrode (503), the right foot voltage sampling electrode (504), the left chest voltage sampling electrode (509), the right chest voltage sampling electrode (510), the left abdomen voltage sampling electrode (511), and the right abdomen voltage sampling electrode (512); The fourth analog switch chip U15 is respectively connected to the main control circuit (100), the output end of the voltage sampling circuit (300), the left chest voltage sampling electrode (509), the right chest voltage sampling electrode (510), the left abdomen voltage sampling electrode (511), and the right abdomen voltage sampling electrode (512).
3. The sixteen-electrode bioimpedance test circuit according to claim 1, wherein: It also includes a weight detection circuit (600) connected to the power supply circuit and the main control circuit (100) respectively, and is used to detect the weight of the measured object.
4. The sixteen-electrode bioimpedance test circuit according to claim 1, wherein: It also includes a calibration circuit (700) connected to the channel switching circuit (400) and used for calibrating impedance parameters.
5. The sixteen-electrode bioimpedance test circuit according to claim 4, characterized in that: The calibration circuit (700) includes resistors R125-R127, one end of the resistor R125 is connected to the channel switching circuit (400), the other end of the resistor R125 is connected to one end of the resistor R126 and the channel switching circuit (400), the other end of the resistor R126 is connected to the channel switching circuit (400) and one end of the resistor R127, and the other end of the resistor R127 is connected to the channel switching circuit (400).
6. The sixteen-electrode bioimpedance test circuit according to claim 1, characterized in that: It also includes a filter circuit (800) connected between the electrode assembly (500) and the channel switching circuit (400).
7. The sixteen-electrode bioimpedance test circuit according to claim 1, characterized in that: It also includes a signal amplifying circuit (900) connected between the left hand voltage sampling electrode (501), the right hand voltage sampling electrode (502), the left foot voltage sampling electrode (503), the right foot voltage sampling electrode (504), the left chest voltage sampling electrode (509), the right chest voltage sampling electrode (510), the left abdomen voltage sampling electrode (511), the right abdomen voltage sampling electrode (512) and the channel switching circuit (400).
8. A body fat scale, characterized by: The bioimpedance testing circuit comprises the bioimpedance testing circuit according to any one of claims 1 to 7.