A programmable neuro-electric stimulation system based on ultrasonic energy supply

Abstract

The application discloses a programmable nerve electric stimulation system based on ultrasonic energy supply, which comprises an ultrasonic transmitter, a piezoelectric receiver, a rectifier, a power management module, a data demodulation circuit, a control module, an H-bridge driving circuit, a current digital-analog converter and an H-bridge circuit; the external ultrasonic transmitter can emit ultrasonic waves to supply power to the system and transmit data, and the piezoelectric receiver receives the ultrasonic signals and converts them into alternating current signals; the rectifier and the power management module can convert the alternating current signals into direct current signals to provide power supply for the rest of the circuit of the system, the data demodulation circuit processes the alternating current signals to recover the data information in the ultrasonic waves, the control module controls the H-bridge driving circuit and the current digital-analog converter according to the data information, and finally realizes electric stimulation through the H-bridge.The system has the characteristics of wireless energy supply, high safety and programmable stimulation parameters, and can realize precise control of the output current parameters.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of medical devices, and particularly relates to a programmable nerve electric stimulation system based on ultrasonic energy supply. BACKGROUND

[0002] In recent years, with the continuous integration and development of electronic technology and the biomedical field, electric stimulators have developed rapidly and have great prospects in the field of biomedical engineering. Due to its wide application in the treatment of various diseases, it has gradually become an important research direction in the medical field. Electric stimulators are mainly used in the treatment of neurological diseases, rehabilitation of muscle atrophy, and treatment of heart disease, etc. Traditional implantable electric stimulators face problems such as large size, high power consumption, single function, poor adjustability, etc., which limits their application in miniaturization, long-term use and personalized treatment.

[0003] To realize a safer and controllable electric stimulator, a wireless energy supply and control method can be used, such as the technical solution provided in document [Chia-Chi Hsieh, Yi-Hui Wu, Ming-Dou Ker. Design of a dual-configurable dual-mode stimulator in low-voltage CMOS process for neuromodulation, IEEE Journal of Biomedical Circuits and Systems, April 2023, Vol. 17, No. 2, pp. 273-285] to support voltage and current stimulation mode, but still requires wired power supply; the technical solution provided in document [Chang-Chun Yang, Ming-Dou Ker. Miniaturized wireless-powered two-phase current stimulator for implantable neural stimulation, IEEE International Conference on Circuits and Systems, London, UK, May 2025] integrates a wireless energy supply module, but the stimulation frequency is fixed and cannot be adjusted, and the application range is relatively single. SUMMARY

[0004] In view of the above, the present application provides a programmable nerve electric stimulation system based on ultrasonic energy supply, which realizes wireless charging and data transmission through ultrasonic waves, and adopts an H-bridge circuit for output, enabling precise control of output current parameters.

[0005] A programmable nerve electric stimulation system based on ultrasonic energy supply, comprising an ultrasonic transmitter, a piezoelectric receiver, a rectifier, a power management module, a data demodulation circuit, an H-bridge circuit, an off-chip energy storage capacitor, a current source, an H-bridge drive circuit, a current digital-to-analog converter, and a control module, wherein:

[0006] The ultrasonic transmitter supplies energy to the system and transmits data by emitting ultrasonic waves;

[0007] The piezoelectric receiver is used to receive ultrasonic waves and convert them into alternating current signals;

[0008] The rectifier is used to convert the AC signal into a DC voltage V. REC ;

[0009] The power management module is based on DC voltage V. REC The conversion process charges the off-chip energy storage capacitor and simultaneously provides the system with operating voltage and reference current I. REF ;

[0010] The data demodulation circuit is used to demodulate the AC signal to recover the data information contained in the ultrasound.

[0011] The H-bridge circuit is used to output current stimulation through electrodes;

[0012] The H-bridge drive circuit is used to drive the switching devices in the H-bridge circuit to adjust the pulse width and frequency of the output current.

[0013] The control module converts the demodulated data information into control signals to control the H-bridge drive circuit and the current-to-analog converter.

[0014] The current-to-analog converter is based on a reference current I. REF In addition to the control signals provided by the control module, an adjustable current I is generated. DAC Used to control the magnitude of the current source in order to adjust the amplitude of the output current;

[0015] The input power supply terminal of the current source is connected to the H-bridge circuit, and the output terminal is grounded, used for copying I. DAC And amplified by a certain factor, it is used as the output current.

[0016] Furthermore, the power management module includes a charge pump circuit, a bandgap reference circuit, and an LDO (low dropout linear regulator), wherein the charge pump circuit is used to regulate the DC voltage V. REC After amplification, the external energy storage capacitor is charged, and then the capacitor voltage V on the capacitor is utilized. DDH Power is supplied to the H-bridge circuit and the H-bridge drive circuit; the bandgap reference circuit is used to convert the DC voltage V REC Converted to reference voltage V REF This generates a reference current I. REF The LDO is based on V REC and V REF Generate a DC voltage V of 1.8V. LDO It is used to provide operating voltage for the control module and the current-to-analog converter.

[0017] Furthermore, the H-bridge circuit consists of four switching transistors M1 to M4, wherein the source of M1 is connected to the source of M2 and connected to the input power supply terminal of the current source, and the drain of M3 is connected to the drain of M4 and connected to the capacitor voltage V.DDH The drain of M1 is connected to the source of M3 and one end of the electrode, the drain of M2 is connected to the source of M4 and the other end of the electrode, and the gates of M1-M4 are connected to switching clock signals Φ1-Φ4 provided by the H-bridge driving circuit. The on or off of the switching tubes is realized by controlling the size of the gate voltage, thereby realizing four modes of forward stimulation, reverse stimulation, disconnection and grounding.

[0018] Further, the switching tubes M1-M4 are NLDMOS (N-type lateral diffusion metal oxide semiconductor field effect tubes).

[0019] Further, the H-bridge driving circuit comprises four PMOS tubes M 10 , M 11 , M 17 , M 18 , eight NMOS tubes M5-M8 and M 12 , M 15 , two NLDMOS tubes M9 and M 16 , two capacitors C1 and C2, two current sources I1 and I2, and four resistors R1-R4, wherein the source of M 17 is connected to the source of M 18 and the input power supply end of I1 and is connected to a direct current voltage V REC , the source of M 10 is connected to the source of M 11 and the input power supply end of I2 and is connected to a direct current voltage V REC , the drain of M 17 is connected to the gate of M 18 , the gate of M 17 and the drain of M 15 , the drain of M 10 is connected to the gate of M 11 , the gate of M 10 and the drain of M8, the gate of M8 and the gate of M 15 are connected to control signals V1 and V2 provided by the control module, the source of M8 is connected to the drain of M6, the source of M 15 is connected to the drain of M 13 , the output end of I1 is connected to the drain of M 12 , the gate of M 12 , the gate of M 13 and the gate of M 14 , the output end of I2 is connected to the drain of M5, the gate of M5, the gate of M6 and the gate of M7, the drain of M 18 is connected to one end of R3 and generates a switching clock signal Φ2, the drain of M 11 is connected to one end of R1 and generates a switching clock signal Φ1, one end of R2 is connected to one end of R4 and is connected to a capacitor voltage VDDH R2, the other end of R2 is connected with the drain of M9 and one end of C1 and generates a switching clock signal Φ3, the other end of R4 is connected with the drain of M9 and one end of C2 and generates a switching clock signal Φ4, the gate of M9 and the gate of M8 are connected with control signals V3 and V4 provided by the control module respectively, the source of M9 is connected with the drain of M7, the source of M8 is connected with the drain of M6, the source of M7 is connected with the drain of M5, the source of M6 is connected with the source of M5, the other end of R1 and the other end of C1 and are connected with the ground, the source of M5 is connected with the source of M6, the source of M7, the other end of R1 and the other end of C1 and are connected with the ground. 16 16 16 14 12 13 14 REF .

[0020] Further, when the amount of electricity on the off-chip energy storage capacitor is sufficient, the control module outputs a high-level stimulation enable signal, and the system starts electrical stimulation; after a single stimulation is completed, due to the release of a large amount of electric charge, the amount of electricity on the off-chip energy storage capacitor is greatly reduced, and the next electrical stimulation cannot be performed, the control module outputs a low-level stimulation enable signal, and at this time the off-chip energy storage capacitor is charged by the power management module; the entire process from the start of electrical stimulation to the completion of charging of the off-chip energy storage capacitor is a stimulation cycle.

[0021] Further, before electrical stimulation starts, the stimulation enable signal is low, and the switching clock signals Φ1-Φ4 are also low, and the switching tubes M1-M4 in the H-bridge circuit are all in the off state, and no current flows through the electrode;

[0022] When electrical stimulation starts, the stimulation enable signal is high, and enters the forward stimulation mode, Φ1 and Φ4 are high, M1 and M4 become conductive state, Φ2 and Φ3 are low, M2 and M3 are still in the off state, and the current flows from the off-chip energy storage capacitor output, through M4→electrode→M1→current source and then flows into the ground; after the forward stimulation ends, Φ1 and Φ4 become low, Φ2 and Φ3 remain low, and M1-M4 are all off, and no current flows through the electrode;

[0023] ​​​​​​​Then enter the reverse stimulation mode, Phi2 and Phi3 are high level, M2 and M3 become on state, Phi1 and Phi4 are low level, M1 and M4 are still off state, the current from the off-chip energy storage capacitor output is M3→electrode→M2→current source and then flows into the ground;After the reverse stimulation, Phi1 and Phi2 become high level, Phi3 and Phi4 become low level, M1 and M2 are on, M3 and M4 are off, the electrode is grounded for charge balance;At this point, a single stimulation is completed, the stimulation enable signal becomes low level, Phi1~Phi4 also become low level, M1~M4 are all off, the off-chip energy storage capacitor is charged by the power management module, and after the charging is completed, the next stimulation cycle is entered.

[0024] Further, the programmable neural electrical stimulation system transmits information by modulating ultrasonic waves, and then restores and utilizes the data information contained in the ultrasonic waves to control and adjust the output current stimulation parameters (amplitude, pulse width, frequency) by demodulation.

[0025] The programmable neural electrical stimulation system based on ultrasonic wave energy supply can rely on ultrasonic waves to cooperate with piezoelectric receivers and rectifiers for wireless power supply, and at the same time, data information is transmitted by ultrasonic waves to control and adjust stimulation parameters, and through the control of stimulation current amplitude, pulse width and frequency and the design of working mode, safe and reliable high-efficiency electrical stimulation is realized. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 It is a structure block diagram of the programmable neural electrical stimulation system of the application.

[0027] Figure 2 It is a circuit structure schematic diagram of the programmable neural electrical stimulation system in the embodiment of the application.

[0028] Figure 3 It is a driving circuit structure schematic diagram of M1 and M3 tubes in the embodiment of the application.

[0029] Figure 4 It is a structure schematic diagram of H bridge and its driving circuit in the embodiment of the application.

[0030] Figure 5 It is an H bridge circuit schematic diagram in the disconnect mode in the embodiment of the application.

[0031] Figure 6 It is an H bridge circuit schematic diagram in the forward stimulation mode in the embodiment of the application.

[0032] Figure 7 It is an H bridge circuit schematic diagram in the reverse stimulation mode in the embodiment of the application.

[0033] Figure 8 It is an H bridge circuit schematic diagram in the ground connection mode in the embodiment of the application.

[0034] Figure 9 Waveform diagram of system related signal under single stimulation in an embodiment of the present application.

[0035] Figure 10 Waveform diagram of current stimulation after adjusting amplitude and frequency to maximum in an embodiment of the present application.

[0036] Figure 11 Waveform diagram of current stimulation after adjusting pulse width to maximum in an embodiment of the present application. DETAILED DESCRIPTION

[0037] In order to describe the present application more specifically, the technical solutions of the present application are described in detail below in combination with the drawings and specific embodiments.

[0038] As shown in the drawings, Figure 1 the present application is based on an ultrasound-powered programmable neuro-electric stimulation system, which comprises an ultrasound transmitter, a piezoelectric receiver, a rectifier, a power management module, a data demodulation circuit, a control module, an H-bridge driving circuit, a current digital-to-analog converter, and an H-bridge circuit, wherein:

[0039] The external ultrasound transmitter can emit ultrasound to power the system and transmit data, and the piezoelectric receiver receives the ultrasound signal and converts it into an alternating current signal; the rectifier can convert the alternating current signal into a direct current signal to provide a direct current voltage source V REC for the system; the data demodulation circuit can process the alternating current signal to recover the data information in the ultrasound, and the control module can control the H-bridge driving circuit (including four groups of switches SW1-SW4) and the current digital-to-analog converter according to the data information; the power management module comprises a charge pump circuit and a bandgap reference circuit, the charge pump can amplify the direct current voltage V REC to generate a relatively large voltage V DDH and store it in an off-chip storage capacitor, and the bandgap reference circuit generates a reference current I REF ; the current digital-to-analog converter generates a current with adjustable amplitude based on the reference current I REF and the signal of the control module.

[0040] EMBODIMENT

[0041] As shown in the drawings, Figure 2 the H-bridge circuit in this embodiment is composed of four NLDMOS transistors M1-M4; the source of M1 and M2 is connected to a current source, the drain of M3 and M4 is connected to V DDH , the drain of M1 and the source of M3 are connected to the right end of the electrode, the drain of M2 and the source of M4 are connected to the left end of the electrode, and the gate voltage Φ1-Φ4 of M1-M4 is controlled by the H-bridge driving circuit.

[0042] As shown in the drawings, Figure 3As shown, in the embodiment, the H-bridge driving circuit, taking the driving circuit of M1 and M3 as an example, is composed of four NMOS tubes M5-M8, one NLDMOS tube M9, two PMOS tubes M10 and M11, one current source I, one capacitor C1 and two resistors R1 and R2. 10 11 REF REF 10 10 REC 10 11 11 REC 11 11 DDH

[0043] The driving circuit of M2 and M4 is the same as that of M1 and M3, and the whole H-bridge circuit and its driving circuit are as shown in FIG. 2. Figure 4

[0044] In the embodiment, the circuit charges the storage capacitor as soon as the piezoelectric receiver receives the ultrasonic wave, and the electric stimulation can be performed only when the electric quantity on the storage capacitor is sufficient.

[0045] The working mode of the H-bridge circuit is controlled by the H-bridge driving circuit, which controls the working state of the four tubes by controlling the gate voltages Φ1-Φ4 of the four NLDMOS tubes.

[0046] In the embodiment, each stimulation cycle process can be divided into five stages S0-S4, and the time of each stage can be flexibly adjusted, which is as follows.

[0047] Before the stimulation starts, Φ1-Φ4 are all low level, M1-M4 are all in the cutoff region, and no current flows through the electrodes, as shown in FIG. 3. Figure 5

[0048] ​​​​​​​​​​​​​​​​Phase S1: at the beginning of forward stimulation, Φ1, Φ4 become high level, M1, M4 become conducting state, Φ2, Φ3 remain low level, M2, M3 remain off, current flows from storage capacitor through M4, electrode, M1, current source and then flows into ground, current flows from left to right through electrode, completing forward stimulation, as shown in Figure 6 .

[0049] Phase S2: after forward stimulation, Φ1, Φ4 become low level, Φ2, Φ3 remain low level, M1-M4 are all off, no current flows through electrode, returning to Figure 5 .

[0050] Phase S3: at the beginning of reverse stimulation, Φ2, Φ3 become high level, M2, M3 become conducting state, Φ1, Φ4 remain low level, M1, M4 remain off, current flows from storage capacitor through M3, electrode, M2, current source and then flows into ground, current flows from right to left through electrode, completing reverse stimulation, as shown in Figure 7 .

[0051] Phase S4: after reverse stimulation, Φ1, Φ2 become high level, Φ3, Φ4 become low level, M1, M2 are on, M3, M4 are off, connecting electrode to ground for charge balance, preventing charge accumulation in human tissue causing harm, as shown in Figure 8 .

[0052] After stimulation, Φ1, Φ2, Φ3, Φ4 all become low level, M1, M2, M3, M4 are all off, returning to Figure 5 .

[0053] After a single stimulation, the amount of electricity on the load capacitor is greatly reduced due to the release of a large amount of charge, so the next stimulation cannot be performed immediately, the circuit will continue to charge the load capacitor, during which M1, M2, M3, M4 remain off, when the next stimulation period comes, the above process will be performed again.

[0054] In a single stimulation period of the embodiment, the stimulation enable signal ST, the input control signals V1-V4 of the H-bridge driving circuit, the gate signals Φ1-Φ4 of M1-M4 in the H-bridge and the output current stimulation I ST waveform are as shown in Figure 9 , S0 represents that stimulation has not started or has ended, S1-S4 correspond to the four phases of the above single stimulation period respectively.

[0055] In the embodiment, the amplitude of the final output current can be controlled by controlling the current size generated by the current digital-to-analog converter, and the pulse width t pw and frequency f of the output current can be controlled by controlling the duration of S1, S3 and the state of the four switching tubes M1-M4 through V1-V4 of the H-bridge driving circuit, so that the output current is controlled.Figure 10 As shown, by adjusting the electrode output current stimulus I ST to 4.53 mA (maximum) and the frequency to 125 Hz (maximum); as shown, by adjusting the electrode output current stimulus I Figure 11 As shown, by adjusting the electrode output current stimulus I ST to 1 ms (maximum). pw to 1 ms (maximum).

[0056] The above description of the embodiments is for the purpose of enabling one of ordinary skill in the art to make and use the application and is not intended to limit the application as construed in the broadest scope of the claims appended hereto. Those skilled in the art will readily understand that the above-described embodiments are merely illustrative of the principles of the application and that various modifications can be made in the embodiments without departing from the scope of the application. Accordingly, the application is not limited to the above-described embodiments, but is intended to cover all modifications falling within the scope of the claims.

Claims

1. A programmable neural electrical stimulation system based on ultrasound power supply, characterized in that, It includes an ultrasonic transmitter, a piezoelectric receiver, a rectifier, a power management module, a data demodulation circuit, an H-bridge circuit, an off-chip energy storage capacitor, a current source, an H-bridge drive circuit, a current-to-analog converter, and a control module, among which: The ultrasonic transmitter powers the system and transmits data by emitting ultrasonic waves. The piezoelectric receiver is used to receive ultrasonic waves and convert them into alternating current signals. The rectifier is used to convert the AC signal into a DC voltage V. REC ; The power management module is based on DC voltage V. REC The conversion process charges the off-chip energy storage capacitor and simultaneously provides the system with operating voltage and reference current I. REF ; The data demodulation circuit is used to demodulate the AC signal to recover the data information contained in the ultrasound. The H-bridge circuit is used to output current stimulation through electrodes; The H-bridge drive circuit is used to drive the switching devices in the H-bridge circuit to adjust the pulse width and frequency of the output current. The control module converts the demodulated data information into control signals to control the H-bridge drive circuit and the current-to-analog converter. The current-to-analog converter is based on a reference current I. REF In addition to the control signals provided by the control module, an adjustable current I is generated. DAC Used to control the magnitude of the current source in order to adjust the amplitude of the output current; The input power supply terminal of the current source is connected to the H-bridge circuit, and the output terminal is grounded, used for copying I. DAC And amplify it by a certain factor to use as the output current; The H-bridge drive circuit includes four PMOS transistors M 10 M 11 M 17 M 18 Eight NMOS transistors M5~M8 and M 12 ~M 15 Two NLDMOS transistors, M9 and M 16 Two capacitors C1 and C2, two current sources I1 and I2, and four resistors R1 to R4, where M 17 The source and M 18 The source of I1 is connected to the input power supply terminal of I1 and connected to a DC voltage V. REC M 10 The source and M 11 The source of I2 is connected to the input power supply terminal of I2 and connected to a DC voltage V. REC M 17 The drain and M 18 gate, M 17 The gate and M 15 The drains are connected, M 10 The drain and M 11 gate, M 10 The gate of M8 is connected to the drain of M8, and the gate of M8 is connected to the drain of M8. 15 The gates of M8 and M6 are respectively connected to control signals V1 and V2 provided by the control module. The source of M8 is connected to the drain of M6. 15 The source and M 13 The drain of I1 is connected to M. 12 Drain, M 12 gate, M 13 The gate and M 14 The gates of M5, M6, and M7 are connected together. The output of I2 is connected to the drain of M5, the gate of M5, the gate of M6, and the gate of M7. 18 The drain of M is connected to one end of R3 and generates the switching clock signal Φ2. 11 The drain of R1 is connected to one end of R1 to generate the switching clock signal Φ1. One end of R2 is connected to one end of R4 and connected to the capacitor voltage V. DDH The other end of R2 is connected to the drain of M9 and one end of C1 to generate the switching clock signal Φ3. The other end of R4 is connected to M9. 16 The drain of M1 and one end of C2 are connected to generate the switching clock signal Φ4. The gate of M9 and M2 are connected to the gate of M1. 16 The gates of M9 and M7 are respectively connected to control signals V3 and V4 provided by the control module. The source of M9 is connected to the drain of M7. 16 The source and M 14 The drains are connected, M 12 The source and M 13 The source, M 14 The source of M5, the other end of R3, and the other end of C2 are connected to ground. The source of M5 is connected to the source of M6, the source of M7, the other end of R1, and the other end of C1, and grounded. The magnitudes of I1 and I2 are the reference current I. REF .

2. The programmable neural electrical stimulation system based on ultrasound power supply according to claim 1, characterized in that: The power management module includes a charge pump circuit, a bandgap reference circuit, and an LDO, wherein the charge pump circuit is used to regulate the DC voltage V. REC After amplification, the external energy storage capacitor is charged, and then the capacitor voltage V on the capacitor is utilized. DDH Power is supplied to the H-bridge circuit and the H-bridge drive circuit; the bandgap reference circuit is used to convert the DC voltage V REC Converted to reference voltage V REF This generates a reference current I. REF The LDO is based on V REC and V REF Generate a DC voltage V of 1.8V. LDO It is used to provide operating voltage for the control module and the current-to-analog converter.

3. The programmable neural electrical stimulation system based on ultrasound power supply according to claim 2, characterized in that: The H-bridge circuit consists of four switching transistors M1 to M4. The source of M1 is connected to the source of M2 and then to the input power supply of the current source. The drain of M3 is connected to the drain of M4 and then to the capacitor voltage V. DDH The drain of M1 is connected to the source of M3 and connected to one end of the electrode. The drain of M2 is connected to the source of M4 and connected to the other end of the electrode. The gates of M1 to M4 are respectively connected to the switching clock signals Φ1 to Φ4 provided by the H-bridge drive circuit.

4. The programmable neural electrical stimulation system based on ultrasound power supply according to claim 3, characterized in that: The switching transistors M1 to M4 are NLDMOS.

5. The programmable neural electrical stimulation system based on ultrasound power supply according to claim 3, characterized in that: When the external energy storage capacitor has sufficient charge, the control module outputs a high-level stimulation enable signal, and the system begins electrical stimulation. After a single stimulation is completed, due to the release of a large amount of charge, the charge on the external energy storage capacitor is greatly reduced, making it impossible to perform the next electrical stimulation. At this time, the control module outputs a low-level stimulation enable signal, and the power management module charges the external energy storage capacitor. The entire process from the start of electrical stimulation to the completion of charging of the external energy storage capacitor is one stimulation cycle.

6. The programmable neural electrical stimulation system based on ultrasound power supply according to claim 5, characterized in that: Before the electrical stimulation begins, the stimulation enable signal is at a low level, and the switching clock signals Φ1 to Φ4 are also at a low level. The switching transistors M1 to M4 in the H-bridge circuit are all in the off state, and no current flows through the electrodes. When electrical stimulation begins, the stimulation enable signal is high, entering the positive stimulation mode. Φ1 and Φ4 are high, M1 and M4 are turned on, Φ2 and Φ3 are low, and M2 and M3 remain off. Current flows from the external energy storage capacitor through M4 → electrode → M1 → current source to ground. After positive stimulation ends, Φ1 and Φ4 become low, Φ2 and Φ3 remain low, M1 to M4 are all turned off, and no current flows through the electrodes. Then, the reverse stimulation mode is entered. Φ2 and Φ3 are at high level, M2 and M3 are turned on, Φ1 and Φ4 are at low level, and M1 and M4 remain off. The current flows from the external energy storage capacitor through M3 → electrode → M2 → current source and then into the ground. After the reverse stimulation ends, Φ1 and Φ2 become high level, Φ3 and Φ4 become low level, M1 and M2 are turned on, and M3 and M4 are turned off. The electrodes are grounded for charge balance. At this point, a single stimulation is completed. The stimulation enable signal becomes low level, Φ1 to Φ4 also become low level, and M1 to M4 are all turned off. The power management module charges the external energy storage capacitor. After charging is completed, the next stimulation cycle begins.

7. The programmable neural electrical stimulation system based on ultrasound power supply according to claim 1, characterized in that: This system transmits information by modulating ultrasound waves, and then modulates and restores the data information contained in the ultrasound waves to regulate the output current stimulation parameters.

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