Chip-level positioning method for orthopedic surgery navigation based on UWB

Abstract

The application provides a kind of chip-level positioning method of orthopedic surgery navigation based on UWB, installs UWB chip-level wireless positioning module on surgical instrument, the biggest advantage of UWB wireless positioning module is that its bandwidth is wider, so it has good anti-interference, only need to communicate with base station and module in the positioning tracking stage to obtain the spatial position of surgical instrument relative to patient, the wireless positioning technology based on UWB is very mature at present, there are diversities in intraoperative visualization means, can be through mobile phone, tablet computer and other equipment to pay attention to the operation state.Compared with the existing optical positioning system, the application has good robustness, high cost performance, strong real-time performance and other advantages.The large bandwidth of UWB ensures low transmission power.In short-range wireless communication applications, the UWB signal power transmitted by the transmitter is less than 1mW, which greatly prolongs the battery life, ensures a longer system working time, and also has less radiation hazard to the human body.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of surgical navigation positioning, in particular to a chip-level positioning method for orthopedic surgical navigation based on UWB. BACKGROUND

[0002] The spatial positioning technology of surgical navigation is responsible for calculating the spatial positions and postures of patient entities and surgical instruments, and through the positioning device at the end of the surgical instrument and the introduction of the spatial conversion relationship, real-time monitoring and control of the surgical process are realized. In the surgical navigation system, the conversion relationship between the surgical instrument coordinate system, the patient coordinate system and the robot coordinate system can be established through the spatial positioning technology. At present, according to different positioning principles, it can be divided into electromagnetic positioning, ultrasonic positioning and optical positioning.

[0003] The hardware of the electromagnetic positioning mode includes a magnetic field detector and a transmitter, generally including three transmitters and one detector. The transmitter is placed under the operating table, and the position of the detector can be determined by the signals received by the transmitter and the relative position between them. The position of the target is calculated by detecting the direction and intensity of the magnetic field in the operating area, and the positioning error is 1-3 mm.

[0004] The ultrasonic positioning mode is to fix the receiver on the surgical instrument, calculate the distance from the receiver to the transmitter through the propagation time and speed of sound, and then determine the position of the receiver through the method of expanding the search radius, and the error is generally 4-5 mm.

[0005] Optical positioning is divided into infrared optical positioning and visible light optical positioning, and the former can be divided into target active optical positioning and camera active optical positioning. The optical positioning system requires that a positioning support is installed on the body surface mapping of the lesion site and the surgical instrument, and some feature points are arranged on the support, such as infrared light-emitting diodes, fluorescent balls reflecting infrared light and black and white chessboard patterns. The spatial information of any rigid body can be determined by three non-collinear spatial points on it in theory. The optical positioning is to position the feature points on the support, so as to calculate the distance and angle information of the surgical instrument and the lesion site.

[0006] The defects of electromagnetic positioning are very sensitive to metal objects and are easily disturbed, especially the ferromagnetic instruments such as high-frequency surgical knives, which can greatly affect the accuracy of electromagnetic positioning.

[0007] The initial setting of ultrasonic positioning is set according to the ideal sound speed, but when the environment changes, a large error will be generated, which will affect the positioning accuracy of the operation.

[0008] Optical positioning will affect the positioning accuracy when the light is blocked, and the number of cameras needs to be increased to improve the reliability of this positioning method. Moreover, the current mainstream optical positioning system is very cumbersome in preoperative configuration of the operating environment, and the system operation is complex. There is a big deviation between the doctor's proficiency in mastering the equipment and the current usage rate. The device is expensive and has low cost performance. SUMMARY

[0009] The application provides a real-time positioning and tracking of surgical instruments based on UWB chip-level positioning technology. UWB positioning has the advantages of high resolution, wide spectrum, low power consumption and strong penetration. When positioning and tracking surgical instruments, it has the advantages of convenient system operation, high cost performance, high accuracy, strong real-time performance and high robustness.

[0010] To achieve the above object, the application provides the following technical scheme: a chip-level positioning method for orthopedic surgery navigation based on UWB, comprising the following steps:

[0011] S1, laying a positioning base station and arranging a UWB wireless positioning module on the surgical instrument. The positioning base station and the UWB wireless positioning module arranged on the surgical instrument use the same UWB module unit;

[0012] S2, real-time positioning. First, substitute the original TDOA value into the Chan algorithm to calculate the preliminary positioning coordinates of the UWB positioning tag. Then calculate the residual sum of squares and set a threshold. Remove the TDOA measurement values with errors higher than the threshold. Re-substitute the filtered TDOA measurement values meeting the requirements into the standard EKF filtering algorithm to obtain the final position coordinates of the surgical instrument.

[0013] Preferably, the specific steps in step S2 are:

[0014] S21, TDOA positioning;

[0015] TDOA time difference of arrival algorithm. This algorithm measures the time difference between the time when two reference base stations receive the broadcast signal sent by the target node. The distance difference between the target node and the two reference base stations is calculated by multiplying the wave speed by the time. Two reference base stations are used as the focal points of the curve, and the distance difference between the two base stations is 2a to obtain the hyperbolic equation. One hyperbolic equation cannot solve the target node, so at least three base stations are used to obtain two hyperbolic equations. The intersection point of the hyperbolic curve is the target node;

[0016] S22, Chan algorithm based on TDOA technology positioning;

[0017] The position of the target is located by using two-step weighted least square (WLS). The positioning system is applicable to both small and large ranges. In the solving process, the nonlinear TDOA equation set is first converted into a linear equation, and then the initial solution is estimated by WLS; and the result is calculated again by WLS under the condition of correlation, so as to further estimate the coordinates of the positioning tag;

[0018] S23, EKF algorithm based on TDOA positioning technology;

[0019] In the UWB positioning system based on TDOA technology, the TDOA equation set is a nonlinear equation, so the extended Kalman filter is used to solve the nonlinear problem. The idea of the extended Kalman filter is that for a nonlinear system, the system can be discretized by numerical analysis means, the Taylor expansion is performed in the neighborhood of the calculation point, the terms higher than the second order are deleted, and only the first order term is retained, so that the Kalman filter is applied to the nonlinear system.

[0020] S24, estimation of the position coordinates of the positioning tag;

[0021] The TDOA measurement value with smaller error selected is brought into the standard EKF filtering algorithm again, so as to obtain the position coordinates of the surgical instrument;

[0022] Preferably, the specific linear equation of the TDOA positioning in the step S21 is:

[0023] The coordinates of the base stations are clockwise set as (x1, y1), (x2, y2), and (x3, y3) from BS1, so the tag coordinates to be solved are (x, y), and the arrival time of the measured node signal at BS1 is t i (i=2, 3), and BS i is the focus, and D i,1 =d i -d1=2a draw a hyperbolic equation, and the distance relationship between the measured node and the base station i is obtained by using the distance formula between two points:

[0024]

[0025] The distance relationship between the distance between the measured node and the main positioning base station BS1 and the distance D i between the distance and the time difference is as follows:

[0026]

[0027] c represents the propagation speed of the electromagnetic wave emitted by the target in the medium. In addition to the main base station, more than two base stations are required to complete the determination of the target node, so the following hyperbolic nonlinear equation set is obtained:

[0028]

[0029] Solve x, y by Chan algorithm, and get the tag coordinates;

[0030] Preferably, the step S23 is based on the specific linear equation of the EKF algorithm for positioning based on TDOA technology:

[0031] Suppose the nonlinear system is:

[0032]

[0033] Time update equation:

[0034]

[0035] Update measurement equation:

[0036]

[0037]

[0038]

[0039] In the above process, φ is the state transition matrix; H is the Jacobian matrix of h function with respect to the state.

[0040] T is the sampling time, and has

[0041] φ = I + F × T

[0042] In the formula, f is the state equation; h is the observation equation; x is the state quantity; u is the input quantity; w and v are process noise and observation noise; P is the error covariance matrix; and K is the Kalman gain.

[0043] Preferably, the specific linear equation for positioning the tag position coordinate estimation in the S24 is:

[0044] First, the original TDOA value is substituted into the Chan algorithm to calculate the preliminary positioning coordinates of the UWB positioning tag, and then the residual sum of squares is calculated, and the calculation formula is:

[0045]

[0046] Then, the error is removed. The role of the residual is to measure the closeness between a group of TDOA values and the corresponding positioning results. In the case that the main source of error in the UWB positioning system is NLOS error, the greater the influence of NLOS error on a group of measured values, the greater the residual value calculated;

[0047] Therefore, the threshold value is set as R ws≤ Δ, compare with the residual value, eliminate the TDOA measurement value containing larger NLOS error;

[0048] When the residual value is greater than the threshold value, it indicates that the distance difference of the estimated coordinates calculated by the Chan algorithm to the base station and the TDOA measurement value between the tag and the base station obtained by the sensor measurement has larger deviation, when the NLOS error is the main error of the positioning system, it indicates that the TDOA measurement value contains larger NLOS error, and then the corresponding group of TDOA measurement values are eliminated;

[0049] If the residual value is less than or equal to the threshold value, the measurement error is considered to be smaller;

[0050] Finally, the position coordinate estimation of the positioning tag is obtained by re-entering the selected TDOA measurement value with smaller error into the standard EKF filtering algorithm, so that the position coordinate of the surgical instrument can be obtained.

[0051] Preferably, the UWB module unit comprises a main control chip, a signal processing chip, a radio frequency power amplifier circuit and a power supply unit which are electrically connected in sequence, and the radio frequency power amplifier circuit is further electrically connected with a three-state power buffer.

[0052] Preferably, the electrical connection between the main control chip and the signal processing chip is bidirectional electrical connection.

[0053] Preferably, the model of the main control chip is STM32F407, the model of the signal processing chip is DW100, the model of the power supply unit is TPS61240, and the model of the three-state power buffer is SN74LV1T125.

[0054] Compared with the prior art, the present application has the following advantages:

[0055] The present application has the advantages that a UWB chip-level wireless positioning module is installed on a surgical instrument, the biggest advantage of the UWB wireless positioning module is that it has a wide bandwidth, so it has good anti-interference performance, only the communication between the base station and the module is needed in the positioning and tracking stage to obtain the spatial position of the surgical instrument relative to the patient, the wireless positioning technology based on UWB is very mature at present, and the intraoperative visualization means has diversity, so the surgical state can be concerned through a mobile phone, a tablet computer and the like. Compared with the existing optical positioning system, the present application has the advantages of good robustness, high cost performance, strong real-time performance and the like. BRIEF DESCRIPTION OF DRAWINGS

[0056] Figure 1 It is a structure block diagram of the UWB module unit in the present application;

[0057] Figure 2 It is a TDOA three-base station positioning schematic diagram in the present application;

[0058] Figure 3 The schematic diagram of the whole algorithm of the application is shown in the figure;

[0059] Figure 4 The bandwidth comparison chart in the application is shown in the figure;

[0060] Figure 5 The spectrum comparison chart in the application is shown in the figure. DETAILED DESCRIPTION

[0061] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative efforts belong to the protection scope of the application.

[0062] Please refer to Figures 1-5 The application provides a technical solution: a chip-level positioning method for orthopedic surgery navigation based on UWB, comprising the following steps:

[0063] S1, laying a positioning base station and arranging a UWB wireless positioning module on a surgical instrument, the positioning base station and the UWB wireless positioning module arranged on the surgical instrument adopt the same UWB module unit;

[0064] S2, real-time positioning, first, substituting the original TDOA value into the Chan algorithm to calculate and obtain the preliminary positioning coordinates of the UWB positioning tag, then calculating the residual sum of squares and setting a threshold value, eliminating the TDOA measurement value with an error higher than the threshold value, and re-substituting the filtered TDOA measurement value meeting the requirements into the standard EKF filtering algorithm, so as to obtain the final position coordinates of the surgical instrument.

[0065] The application needs to arrange a UWB wireless positioning module on the surgical instrument, and the specific scene arrangement is arranged according to actual needs. The scheme design mainly consists of two parts of software design and hardware design, and the specific implementation modes of the software and hardware are shown in Figure 1 and Figure 3

[0066] In the hardware design part, the positioning base station and the positioning tag adopt the same UWB module unit, the UWB module unit comprises a main control chip, a signal processing chip, a radio frequency power amplifier circuit and a power supply unit which are electrically connected in sequence, and the radio frequency power amplifier circuit is further electrically connected with a three-state power buffer.

[0067] Preferably, the electrical connection mode between the main control chip and the signal processing chip is bidirectional electrical connection.

[0068] ​Preferably, the model of the main control chip is STM32F407, the model of the signal processing chip is DW100, the model of the power supply unit is TPS61240, and the model of the tri-state power buffer is SN74LV1T125.

[0069] The DW100 chip of Decawave Company is used as the UWB signal processing chip, which conforms to the wireless standard; in order to enhance the anti-interference capability, the wireless radio frequency signal is amplified, the TPS61240 chip is used to supply power for the radio frequency power amplifier circuit, and the tri-state power buffer SN74LV1T125 is used to enhance the anti-vibration capability of the power supply circuit and improve the robustness.

[0070] Preferably, the specific steps in the step S2 are:

[0071] S21, TDOA positioning;

[0072] TDOA time difference of arrival algorithm, which is to measure the time difference between the time when two reference base stations receive the broadcast signal sent by the target node, to obtain the distance difference between the target node and the two reference base stations by multiplying the wave speed by the time, to obtain the hyperbolic equation by taking the two reference base stations as the foci and the distance difference between the signals reaching the two base stations as 2a, and to obtain the target node by using at least three base stations to obtain two hyperbolic equations and the intersection point of the hyperbolic equations is the target node;

[0073] S22, Chan algorithm based on TDOA technology positioning;

[0074] Two-step weighted least squares (WLS) is used to position and solve the position of the target. It is applicable in small and large range positioning systems. In the solving process, the nonlinear TDOA equation set is first processed and converted into a linear equation, and then the initial solution is estimated by WLS; the result is calculated again using WLS under the related conditions, and the coordinates of the positioning tag are further estimated;

[0075] S23, EKF algorithm based on TDOA technology positioning;

[0076] In the UWB positioning system based on TDOA technology, the TDOA equation set is a nonlinear equation, so the extended Kalman filter is used to solve the nonlinear problem. The idea of extended Kalman filter is that for a nonlinear system, the system can be discretized by numerical analysis means, the Taylor expansion is performed in the neighborhood of the calculation point, the terms exceeding the second order are deleted, and only the first order term is retained, so that the Kalman filter can be applied to the nonlinear system.

[0077] S24, positioning tag position coordinate estimation;

[0078] By substituting the selected TDOA measurements with smaller errors back into the standard EKF filtering algorithm, the final position coordinates of the surgical instruments can be obtained.

[0079] Preferably, in step S21, the specific linear equation for TDOA positioning is:

[0080] The coordinates of each base station are assigned clockwise from BS1 as (x1, y1), (x2, y2), and (x3, y3), respectively. Therefore, the tag coordinates to be solved are (x, y), and the arrival time of the measured signal from the node under test at BS1 is t. i (i = 2, 3), with BS1 and BS i With D as the focus i,1 =d i Draw the hyperbola equation for -d1 = 2a. The distance relationship from the node to be measured to base station i can be obtained using the distance formula between two points:

[0081]

[0082] The distance D from the node under test to the main positioning base station BS1 and the distance D to other base stations. i The relationship between the distance and the time difference is shown below:

[0083]

[0084] c represents the propagation speed of the electromagnetic wave emitted by the target in the medium. In addition to the main base station, two or more base stations are needed to complete the determination of the target node. From this, the following hyperbolic nonlinear equation system can be obtained:

[0085]

[0086] The label coordinates are obtained by solving for x and y using the Chan algorithm.

[0087] Preferably, in step S23, the specific linear equation of the EKF algorithm based on TDOA technology localization is as follows:

[0088] Let the nonlinear system be:

[0089]

[0090] Time update equation:

[0091]

[0092]

[0093] Update the measurement equation:

[0094]

[0095]

[0096]

[0097] In the above flow, φ is a state transition matrix; H is a Jacobian matrix of h function on state.

[0098] T is a sampling time, and has

[0099] φ = I + F × T

[0100] In the formula, f is a state equation; h is an observation equation; x is a state quantity; u is an input quantity; w and v are process noise and observation noise; P is an error covariance matrix; and K is a Kalman gain.

[0101] Preferably, the specific linear equation for estimating the position coordinate of the positioning tag S24 is:

[0102] First, the original TDOA value is substituted into the Chan algorithm to calculate the preliminary positioning coordinate of the UWB positioning tag, and then the residual sum of squares is calculated, and the calculation formula is:

[0103]

[0104] Then, the error is removed. The role of the residual is to measure the closeness between a group of TDOA values and the corresponding positioning results. In the case that the main source of error in the UWB positioning system is NLOS error, the greater the NLOS error affecting a group of measured values, the greater the residual value calculated by it;

[0105] Therefore, the threshold value R is set to be ws ≤ Δ, and compared with the residual value, the TDOA measurement value containing a large NLOS error is removed;

[0106] When the residual value is greater than the threshold value, it means that the distance difference between the estimated coordinate calculated by the Chan algorithm and the TDOA measurement value between the tag and the base station measured by the sensor is large. When NLOS error is the main error of the positioning system, it means that the TDOA measurement value contains a large NLOS error, and then the corresponding group of TDOA measurement values is removed.

[0107] If the residual value is less than or equal to the threshold value, it is considered that the error of the measurement value is small.

[0108] Finally, the positioning tag position coordinate estimation re-enters the standard EKF filtering algorithm with the TDOA measurement value with small error screened out, and the final position coordinate of the surgical instrument can be obtained.

[0109] The wireless positioning technology based on UWB has the advantages of large system capacity, fast transmission rate, low transmission power and strong real-time.

[0110] As shown in the drawings, Figure 4 The wider the bandwidth is, the greater the maximum transmission rate of the system is, and the bandwidth of UWB communication is above 500MHz, and the transmission rate can be above 1Gbps.

[0111] As shown in the drawings, Figure 5 The great bandwidth of UWB ensures low transmission power. In short-distance wireless communication application, the UWB signal power transmitted by the transmitter is lower than 1mW, which greatly prolongs the battery life, ensures a long system working time, and also reduces the radiation hazard to the human body.

[0112] The real-time and accuracy of UWB measurement means that the system supporting UWB can highly determine the accurate position of the device and whether the device is stationary or mobile.

[0113] The advantage of the present application is that the UWB chip-level wireless positioning module is installed on the surgical instrument, the biggest advantage of the UWB wireless positioning module is that the bandwidth is wide, so it has good anti-interference performance, only the communication between the base station and the module is needed in the positioning and tracking stage to obtain the spatial position of the surgical instrument relative to the patient, the wireless positioning technology based on UWB is very mature at present, and the intraoperative visualization means has diversity, the surgical state can be concerned through mobile phones, tablets and other devices. Compared with the existing optical positioning system, the present application has the advantages of good robustness, high cost performance, strong real-time performance and the like.

[0114] Although the embodiments of the present application have been shown and described, it can be understood by those skilled in the art that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and spirits of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A chip-level positioning method for UWB-based orthopedic surgery navigation, characterized in that, Comprise the following steps: S1, laying the positioning base station, and arranging the UWB wireless positioning module on the surgical instrument, the positioning base station and the UWB wireless positioning module arranged on the surgical instrument adopt the same UWB module unit; S2, real-time positioning, first, the original TDOA value is substituted into Chan algorithm, the preliminary positioning coordinates of UWB positioning tag are calculated, then the residual sum of squares is calculated, and the threshold value is set, the TDOA measurement value with error higher than the threshold value is removed, the TDOA measurement value meeting the requirement is brought into the standard EKF filtering algorithm again, and the final position coordinates of the surgical instrument can be obtained; The specific steps in the step S2 are: S21 ， TDOA positioning; TDOA time difference algorithm, the algorithm is to measure the time difference of the broadcast signal sent by the target node received by two reference base stations, the distance difference of the target node to the two reference base stations is obtained by multiplying the wave speed by the time, the two reference base stations are taken as the focal points of the curve, and the hyperbolic equation is obtained by taking the distance difference of the signal to the two base stations as 2a, one hyperbolic equation cannot solve the target node, so at least three base stations are used to obtain two hyperbolic equations, and the intersection point of the hyperbolic equations is the target node; S22, Chan algorithm based on TDOA technology positioning; The two-step weighted least squares method is used to position and solve the position of the target, which is applicable in small-range and large-range positioning systems, in the solving process, the nonlinear TDOA equation set is first processed and converted into a linear equation, and then the initial solution is estimated by WLS; the result is calculated again using WLS, and the coordinates of the positioning tag are further estimated; S23, EKF algorithm based on TDOA technology positioning; In the UWB positioning system based on TDOA technology, the TDOA equation set is a nonlinear equation, so the extended Kalman filter is used to solve the nonlinear problem, the idea of extended Kalman filter is that for a nonlinear system, the system can be discretized by numerical analysis means, the Taylor expansion in the calculation point neighborhood is carried out, the terms exceeding the second order are deleted, and only the first order term is retained, so that the Kalman filter is applied to the nonlinear system; S24, positioning tag position coordinate estimation; The TDOA measurement value with smaller error is brought into the standard EKF filtering algorithm again, and the final position coordinates of the surgical instrument can be obtained; The specific linear equation of TDOA positioning in the step S21 is: The base station coordinates are set as (x1, y1), (x2, y2), (x3, y3) in clockwise direction from BS1, so the label coordinates to be solved are (x, y), and the time of arrival of the measured node signal at BS1 is t i (i = 2, 3), with BS1, BS i as foci, and D i,1 = d i -d1 = 2a draw hyperbolic equation, the distance relationship between the measured node and the base station i is obtained by the distance formula between two points: The distance between the to-be-measured node and the main positioning base station BSl and the distance D between the to-be-measured node and other base stations i The relationship between the distance and the time difference is as follows: C represents the propagation speed of the electromagnetic wave emitted by the target in the medium, more than two base stations are needed in addition to the main base station to complete the determination of the target node, and the following hyperbolic nonlinear equation set is obtained: The label coordinates are obtained by solving x and y through Chan algorithm; The specific linear equation of EKF algorithm based on TDOA technology positioning in the step S23 is: The nonlinear system is: Time update equation: Update measurement equation: In the above process, φ is the state transition matrix; H is the Jacobian matrix of h function with respect to the state; T is the sampling time, and has φ=I+F×T In the formula, f is the state equation; h is the observation equation; x is the state quantity; u is the input quantity; w and v are process noise and observation noise; P is the error covariance matrix; and K is the Kalman gain.

2. The chip-level positioning method for orthopedic surgery navigation based on UWB according to claim 1, characterized in that: The specific linear equation of the step S24 of positioning the label position coordinate estimation is: Firstly, the original TDOA value is substituted into the Chan algorithm to obtain the preliminary positioning coordinate of the UWB positioning label, and then the residual sum of squares is calculated, and the calculation formula is: Then, the error is removed, the residual is used to measure the closeness between a group of TDOA values and the corresponding positioning results, and in the case that the main source of error of the UWB positioning system is NLOS error, the greater the NLOS error affecting a group of measured values, the greater the residual value calculated by the NLOS error; Therefore, the threshold value is set as R ws ≤ Δ, and the TDOA measurement value containing a larger NLOS error is eliminated by comparing with the residual value. When the residual value is greater than the threshold value, it is indicated that the distance difference between the estimated coordinate calculated by the Chan algorithm and the TDOA measurement value between the label and the base station measured by the sensor is large, and in the case that the NLOS error is the main error of the positioning system, it is indicated that the TDOA measurement value contains a large NLOS error, so the corresponding group of TDOA measurement values is removed; If the residual value is less than or equal to the threshold value, it is considered that the error of the measurement value is small. Finally, the positioning label position coordinate estimation is obtained by re-substituting the TDOA measurement value with small error screened out into the standard EKF filtering algorithm, so that the position coordinate of the surgical instrument is obtained.

3. The chip-level positioning method for orthopedic surgery navigation based on UWB according to claim 2, characterized in that: The UWB module unit comprises a main control chip, a signal processing chip, a radio frequency power amplifier circuit and a power supply unit which are electrically connected in sequence.

4. The chip-level positioning method for orthopedic surgery navigation based on UWB according to claim 3, characterized in that: The electrical connection mode between the main control chip and the signal processing chip is bidirectional electrical connection.

5. The chip-level positioning method for orthopedic surgery navigation based on UWB according to claim 4, characterized in that: The model of the main control chip is STM32F407, the model of the signal processing chip is DW100, the model of the power supply unit is TPS61240, and the model of the three-state power buffer is SN74LV1T125.

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