KR101782693B1

KR101782693B1 - Integrated Circuit for Renal Denervation using multi electrode

Info

Publication number: KR101782693B1
Application number: KR1020150125708A
Authority: KR
Inventors: 배현민; 양재혁; 김서현
Original assignee: 한국과학기술원
Priority date: 2015-09-04
Filing date: 2015-09-04
Publication date: 2017-09-28
Also published as: KR20170028724A

Abstract

An integrated circuit for multi-electrode nephrectomy is presented. The integrated circuit for multi-electrode neurotization according to the present invention includes a regulator for generating and supplying a plurality of voltages required by blocks in the integrated circuit using a supply voltage supplied from a power generator through a VDD line, A communication unit that receives control data from the power generator and transmits the measured information to the power generator using a temperature sensor and an impedance sensor, a temperature sensor that uses a current that increases in proportion to a temperature inside the bandgap reference circuit, An impedance sensor for measuring an impedance by sensing an absolute value of a voltage change, a temperature sensor and a shared ADC for digitizing information measured by the impedance sensor, Including heaters to control temperature by controlling power All.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an integrated circuit for multiple electrode nephrectomy,

The present invention relates to a method and system for multi-electrode neurotization using an integrated circuit.

Resistant hypertension, which accounts for 20% to 30% of all hypertensive patients, refers to a disease in which blood pressure is not controlled below the target level even if three or more blood pressure lowering drugs are used, including diuretics. Neural blockade, a representative treatment for resistant hypertension, blocks the renal nerve that signals the renin-angiotensin-aldosterone system (RAAS), one of the important mechanisms involved in blood pressure control, It is a lowering procedure. The renal sympathetic nerves are located in the sub dermis of the renal artery, and the only place where the afferent and efferent sympathetic nerves pass together is the renal artery.

FIG. 1 is a diagram illustrating an example of a device for the treatment of the kidneys according to the prior art.

The neuroprotective device consists largely of a power generator 110 for generating and controlling high frequency energy in vitro and a catheter 120 for introducing energy into the arterial wall into the kidney 140. The catheter 120 has a long and narrow structure to cut the crotch and enter the artery of the kidney 140 along the aorta 130. The end of the catheter 120 is connected to an electrode for transmitting high frequency energy and a temperature sensor, . AC high frequency waves (350 kHz to 500 kHz) generated by the power generator 110 are transmitted through the catheter 120 to the interior of the elongated artery 140 by the energy of several watts W, And then back out. The renal artery blood vessel wall contacting the electrode of the catheter 120 has a high current density so that energy is concentrated, and energy of the extracellular skin contacting the patch-shaped electrode is dispersed. Since cells in our body die within 6 minutes at temperatures of 50 to 60 degrees and immediately destroy at temperatures of 60 to 90 degrees, the concentrated high frequency energy raises the temperature of the renal artery wall and destroys sympathetic nerve cells. The temperature of the vessel wall is monitored in real time and feedback information is passed back to the power generator 110 to maintain approximately 65-70 degrees.

One procedure has a disadvantage in that it takes a long time to perform the procedure, and the risk of side effects and complications of the patient is increased because a single electrode system using one electrode, which is spiraled along the inner wall of the artery, spans 6-7 points. Also, if one electrode is used, it is required to maintain a proper position of the blood vessel wall at the time of the procedure because it depends on the direct control of the doctor.

Although the multi-electrode system using multiple electrodes and sensors can shorten the procedure time, the number of wires connected to the external control device increases in proportion to the number of electrodes. The multiple wires increase the diameter of the catheter 120 that must pass through the vessel, thereby hindering efficient procedures, as well as increasing the cost of equipment by reducing yield during equipment fabrication.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to overcome the disadvantages of the related art neuroretinal device requiring a longer operation time and increased risk of side effects and complications of the patient, Electrode nephronectomy method and system using an integrated circuit for improving the disadvantage that a professional technique is required because it is dependent on direct control by a physician to keep the neuron in a proper position. In addition, although the conventional multi-electrode system using a plurality of electrodes and sensors can shorten the procedure time, the number of wires connected to the external control device increases in proportion to the number of electrodes, so that the diameter of the catheter is increased It not only hinders efficient operation but also has a disadvantage of increasing the cost of the equipment by reducing the yield in the equipment manufacturing process. Accordingly, there is a need to provide a method and system for multi-electrode renal nerve ablation using an integrated circuit for solving such problems.

In one aspect, an integrated circuit for multi-electrode neurotization disclosed in the present invention uses a supply voltage supplied from a power generator via a VDD line to generate a plurality of voltages required by each block in the integrated circuit A communication section for receiving the control data from the power generator and for transmitting the measured information to the power generator using a temperature sensor and an impedance sensor; a current generator for generating a current in proportion to the temperature inside the band gap reference circuit An impedance sensor for measuring an impedance by sensing an absolute value of a voltage change, a temperature sensor, a shared ADC for digitizing information measured by the impedance sensor, a control signal received from the power generator, Data is used to control the temperature by controlling the power consumption It includes a heater.

The heater converts control data received from the power generator into PWM pulses through a PWM pulse generation circuit and controls a plurality of MOSFET switches in parallel using the PWM pulses through a driver circuit to reduce power consumption of the heater And controls the consumed electric power of the resistor of the heater so that heat is directly transmitted to the blood vessel wall through the electrode to cut off the nerve.

The temperature sensor is utilized to increase the supply current amount of the heater when the measured temperature is lower than the target temperature and decrease the supply current amount of the heater when the measured temperature is higher than the target temperature.

The impedance sensor includes a digital sine wave generator for generating a sine wave voltage using a DDS scheme, an alternating current applying circuit for converting a voltage of the generated sine wave into a current and applying an alternating current to the electrode, And a peak detector for detecting peak-to-peak information of the amplified AC voltage.

The shared ADC uses one shared ADC to convert two pieces of measured information through the temperature sensor and the impedance sensor in real time.

Wherein the integrated circuit is embedded in a plurality of electrodes and receives control data for controlling the temperature of a plurality of electrodes sequentially through a single electric wire from the power generator sequentially at predetermined time intervals, And transmits the digitized information to the power generator through a single wire.

The integrated circuit is connected to the power generator using a VDD line, a GND line, and a data line for data communication for supplying a supply voltage, and supplies a supply voltage supplied through the VDD line to a regulator inside the integrated circuit And generates and supplies a plurality of voltages required by the respective blocks in the integrated circuit.

According to another aspect of the present invention, there is provided a method for driving an integrated circuit for multi-electrode renal nerve ablation using a supply voltage supplied from a power generator via a VDD line, Sensing the temperature proportional current in the bandgap reference circuit to measure the temperature; applying a predetermined current through the impedance sensor and sensing the absolute value of the voltage change to generate an impedance Digitizing information measured by the temperature sensor and the impedance sensor via a shared ADC, digitizing the measured information using the temperature sensor and the impedance sensor, and transmitting the digitized information to the power generator, Based on the information measured using the temperature sensor and the impedance sensor Using the received control data received from the power generator includes the step of adjusting the temperature by controlling the power consumption of the heater.

The step of measuring the temperature using the bandgap reference circuit of the temperature sensor detects the temperature information by sensing a current that increases in proportion to the temperature through the resistor.

The step of applying the predetermined current through the impedance sensor and measuring the impedance by sensing the absolute value of the voltage change generates a voltage of the sine wave using the DDS method and converts the voltage of the generated sine wave into the current, Peak information of the amplified AC voltage is detected by amplifying the AC voltage by the AC current applied to the electrode to measure the impedance.

The step of digitizing the information measured by the temperature sensor and the impedance sensor via the shared ADC uses one shared ADC to convert two pieces of information measured through the temperature sensor and the impedance sensor in real time.

Wherein the step of controlling the temperature by controlling the power consumption of the heater using the control data received from the power generator according to the measured information using the temperature sensor and the impedance sensor comprises: And controlling a consumption power of the resistor of the heater by controlling a plurality of MOSFET switches in parallel by using the PWM pulse through a driver circuit to control the consumption power of the resistor, The nerve is resected by direct heat to the vessel wall.

The method for driving an integrated circuit for multi-electrode neurotization comprises sequentially receiving control data for controlling the temperature of a plurality of electrodes from a single power line at a predetermined time interval from the power generator, The measured information is digitized and transmitted to the power generator via the single wire.

According to embodiments of the present invention, there is provided a method and system for multi-electrode renal nerve ablation using an integrated circuit in which a system based on a micro integrated circuit (IC) is placed at the end of a catheter and electrodes are wrapped around the system. A temperature sensor and an impedance sensor are mounted in an integrated circuit (IC) to convert the temperature and impedance information from the inside of the chip into a digital signal and transmit it to a display device outside the body. Therefore, the reliability of the conventional analog signal is higher than that of the analog signal delivered directly through the long wire, so that it is possible to perform more accurate and safe procedures. By using multiple electrodes, the procedure time can be shortened.

FIG. 1 is a diagram illustrating an example of a device for the treatment of the kidneys according to the prior art.
2 is a view showing a six-electrode catheter incorporating an integrated circuit (IC) according to an embodiment of the present invention.
3 is a block diagram of an RDN integrated circuit (IC) system according to an embodiment of the present invention.
4 is a flowchart illustrating a method of multi-electrode renal nerve ablation using an integrated circuit according to an embodiment of the present invention.
5 is a view for explaining a time division communication method according to an embodiment of the present invention.
6 is a diagram for explaining a data transmitting / receiving process according to an embodiment of the present invention.
7 is a diagram for explaining a frequency and phase synchronization check process according to an embodiment of the present invention.
8 is a diagram showing a result of a data communication simulation according to an embodiment of the present invention.
9 is a diagram illustrating a clock and data restoring circuit structure according to an embodiment of the present invention.
10 is a view for explaining the principle of a counter based frequency detector according to an embodiment of the present invention.
FIG. 11 is a diagram showing simulation results of a 3D finite element solver according to an embodiment of the present invention.
12 is a diagram showing the structure of a heater circuit according to an embodiment of the present invention.
13 is a diagram showing a simulation result of a PWM control circuit according to an embodiment of the present invention.
14 is a diagram illustrating a bandgap reference circuit according to an embodiment of the present invention.
15 is a view showing a result of a temperature sensor simulation according to an embodiment of the present invention.
16 is a diagram illustrating an impedance sensing process according to an embodiment of the present invention.
17 is a view showing an alternating current application circuit according to an embodiment of the present invention.
18 is a diagram showing a simulation result of an AC current applying circuit according to an embodiment of the present invention.
19 is a diagram illustrating a PGA circuit according to an embodiment of the present invention.
20 is a block diagram of a peak detector according to an embodiment of the present invention.
FIG. 21 is a diagram showing a simulation result of a peak detector according to an embodiment of the present invention. FIG.
22 is a diagram illustrating a shared analog-to-digital converter (ADC) according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a view showing a six-electrode catheter incorporating an integrated circuit (IC) according to an embodiment of the present invention.

In the present invention, the end of the catheter 210 is replaced by a system based on a micro-integrated circuit (IC) 211 instead of a conventional electrode and a thermocouple for a temperature sensor. As shown in FIG. 2, the IC 211 is mounted on a flexible PCB so as to be able to move smoothly even inside a blood vessel wall, and the electrode 211 is wrapped around the IC 211. The IC 211 includes a switch circuit for controlling the energy from the power generator, an on-chip temperature sensor and an impedance measuring circuit for monitoring the degree of nerve block. The temperature and impedance information is converted to digital in the chip of the IC 211 and sent to an external display device, so that the reliability of the conventional analog signal is higher than that of a conventional analog signal transmitted directly through a long wire. Therefore, more accurate and safe procedures are possible.

For example, in order to shorten the procedure time, the catheter 210 may have six electrodes, each of which houses the IC 211, arranged in a circle with an interval of 60 degrees. In order to solve the problem of increasing the number of wires in proportion to the number of electrodes, the number of wires can be minimized by using a multiplexing technique. Multiplexing is a circuit technique used to maximize utility in a limited physical channel. One power generator sequentially controls a plurality of electrodes with a single wire at regular time intervals. In addition, a basket-type catheter can stably contact the electrode with the blood vessel wall in the blood vessel, so that the catheter can be easily controlled during the procedure.

The proposed IC-based multi-electrode nephronectomy system includes a power generator 110 and a catheter 120 as illustrated in the prior art neuronal blocker device of FIG.

However, unlike the prior art, the power generator of the proposed multi-electrode neurotization system sequentially transmits control data for controlling the temperature of a plurality of electrodes through a single wire at predetermined time intervals, A plurality of electrodes in which an IC controlled by the control data received from the power generator is disposed, digitizes the measured information using the IC, and transmits the digitized information to the power generator through a single wire.

The IC is connected to the power generator using a VDD line, a GND line, and a data line for data communication to supply the supply voltage. The supply voltage supplied through the VDD line is generated and supplied to a plurality of voltages required by the respective blocks inside the IC by using a regulator inside the IC.

Here, a data line for data communication is a single wire that enables bi-directional communication between a power generator and a plurality of ICs using a time division communication method.

The control data is in the form of a packet transmitted from the MCU in the power generator. The packet has predetermined ID data, and the ID indicates that the control data is data transmitted to a specific IC corresponding to a predetermined ID among the ICs built in the plurality of electrodes.

Before transferring such control data, frequency and phase synchronization between the MCU in the power generator and ICs built in the plurality of electrodes is performed. After receiving the control data, the specific IC receiving the control data can transmit the measured information using the IC to the power generator in the next section.

3 is a block diagram of an RDN integrated circuit (IC) system according to an embodiment of the present invention.

The proposed IC 320 includes a regulator 321, a communication unit 322, a temperature sensor 323, an impedance sensor 324, a shared ADC (Shared Analog to Digital Conveter) A heater 326, a clock and data recovery (CDR) circuit 327, and a PWM pulse generation circuit 328.

The regulator 321 generates and supplies a plurality of voltages required by the respective blocks in the IC 320 using the supply voltage supplied from the power generator 310 via the VDD line.

The communication unit 322 including the receiver RX and the transmitter TX receives control data from the power generator 310 and uses a temperature sensor 323 and an impedance sensor 324 And transmits the measured information to the power generator through a single wire. ;

A temperature sensor 323 measures the temperature using a temperature proportional current inside the bandgap reference circuit. The temperature sensor 323 is utilized to increase the supply current amount of the heater when the measured temperature is lower than the target temperature and decrease the supply current amount of the heater when the measured temperature is higher than the target temperature.

An impedance sensor 324 applies a predetermined current and senses the absolute value of the voltage change to measure the impedance. An impedance sensor 324 is a digital sine wave generator for generating a sine wave voltage using the DDS method, an alternating current applying circuit for converting the voltage of the generated sine wave into a current to apply an alternating current to the electrode, A PGA for amplifying an AC voltage generated by an alternating current applied to an electrode to generate an AC voltage, and a peak detector for detecting peak-to-peak information of the amplified AC voltage.

A shared analog to digital converter (ADC) 325 digitizes information measured by a temperature sensor 323 and an impedance sensor 324. A shared analog to digital converter (ADC) 325 is used to convert two pieces of information specified through a temperature sensor 323 and an impedance sensor 324 in real time.

A heater 326 regulates the temperature by controlling power consumption using control data received from a power generator 310. The heater 326 converts the control data received from the power generator 310 into PWM pulses through a PWM pulse generation circuit and drives the plurality of MOSFET switches in parallel So that the power consumption of the resistance of the heater is controlled. Then, by controlling the power consumption of the resistance of the heater 326, heat is directly transmitted to the blood vessel wall through the electrode to excise the nerve.

In other words, the external power generator 310 and the IC 320 embedded in the electrode are connected by a total of three wires for VDD line, GND line, and DATA line for data communication. In order to drive the IC 320, a plurality of power domains are required, but in order to minimize the number of wires, an internal regulator is used to generate necessary supply voltages and supply them to each block. Data communication can also be a one-to-many bi-directional communication with TDMA method using one wire.

The power generator 310 sends control data to adjust the electrode temperature, which is recovered using a clock and data recovery (CDR) circuit operating without an external reference clock. The interpreted data is converted into a PWM pulse to control the heater 326. The temperature of the electrode is always monitored by a temperature sensor 323 inside the IC 320 and digitized by a shared analog to digital converter 325 together with the impedance information and transmitted to the outside . Since the temperature and impedance information sensed by each IC 320 are sequentially transmitted in time according to the TDMA scheme, they can be transmitted to the power generator 310 without interference or collision with each other.

4 is a flowchart illustrating a method of multi-electrode renal nerve ablation using an integrated circuit according to an embodiment of the present invention.

In the proposed multi-electrode neurotization method, a power generator sequentially transmits control data for controlling temperature of a plurality of electrodes through a single wire at predetermined time intervals (step 410) (420) digitizing the measured information using the integrated circuit in the catheter having a plurality of electrodes in which the integrated circuit controlled by the control data received from the control data is disposed, and transmitting the digitized information to the power generator through a single wire.

In step 410, synchronization of frequency and phase between the MCU internal to the power generator and the integrated circuits built in the plurality of electrodes is performed before transferring the control data. Then, the specific integrated circuit receiving the control data receives the control data, and then transmits the measured information to the power generator using the integrated circuit in the next section.

Step 420 includes generating 421 a plurality of voltages required by each block in the integrated circuit through the regulator using the supply voltage supplied from the power generator via the VDD line, A step 422 of measuring a temperature-proportional current inside the sensor, a step 422 of measuring the impedance by applying a predetermined current through the impedance sensor and sensing the absolute value of the voltage change, (424) digitizing the information measured by the impedance sensor, digitizing the measured information using the temperature sensor and the impedance sensor and transmitting the measured information to the power generator through a single wire (425), measuring the temperature sensor and the impedance sensor And the power consumption of the heater is controlled by using the control data received from the power generator according to the measured information, The step of slitting includes step 426.

In step 422, when the measured temperature is lower than the target temperature, the supply current amount of the heater is increased and when the measured temperature is higher than the target temperature, the supply current amount of the heater is decreased.

In step 423, a voltage of a sinusoidal wave is generated using the DDS method, a voltage of the generated sinusoidal wave is converted into a current to apply an alternating current to the electrode, and an alternating current voltage To-peak information of the amplified AC voltage.

In step 424, one shared ADC is used to convert the two pieces of information measured through the temperature sensor and the impedance sensor in real time.

The control data received from the power generator in step 426 is converted into PWM pulses through the PWM pulse generation circuit and the power consumption of the resistor of the heater is controlled by controlling the plurality of MOSFET switches in parallel using the PWM pulse through the driver circuit . By controlling the dissipation power of the resistor, heat is transferred directly to the blood vessel wall through the electrode to excise the nerve. Hereinafter, a method and system for multi-electrode renal nerve ablation using the integrated circuit proposed with reference to FIGS. 5 to 22 will be described in detail.

5 is a view for explaining a time division communication method according to an embodiment of the present invention.

5 (a) shows an example of a multi-electrode system using a plurality of electrodes and sensors according to the prior art. A multi-electrode system using a plurality of electrodes and sensors according to the related art can shorten a procedure time. However, a wire connected to an external control device, that is, a micro controller unit (MCU) (master (TX) The number increases in proportion to the number of electrodes. Multi-wire increases the diameter of the catheter that must pass through the vessel, which interferes with efficient procedures and increases the cost of equipment by reducing yield during equipment manufacturing.

FIG. 5 (b) is a view showing a time division communication method of the multi-electrode neurotization system using the integrated circuit of the proposed method. The external control device, that is, the micro controller unit (Master (TX)) of the power generator is connected to the heater (s) of a plurality of ICs (chip1, chip2, chip3) embedded in the electrode And data communication is required to transmit temperature and impedance information measured in the body to the outside. When a plurality of electrodes are used, the number of wires for communication also increases in proportion to the number of electrodes. However, in the proposed invention, it is possible to perform bi-directional communication with one wire by using the time division method.

6 is a diagram for explaining a data transmitting / receiving process according to an embodiment of the present invention.

6A is a diagram showing a heater of a plurality of ICs (chip1, chip2, chip3) incorporated in an electrode (Electrode) (Slave (RX)) in an MCU (Master Controller Control data is transmitted.

6 (b) is a graph showing the relationship between the measured values of a microcontroller unit (Master (TX)) of a power generator from a plurality of ICs (chip1, chip2, chip3) embedded in an electrode (Slave Temperature and impedance information.

Control data sent from a micro controller unit (Master (TX)) of a power generator to a plurality of ICs (chip1, chip2, chip3) of each electrode is a packet type 610, and each of the packets 611, 612, 613, 614, 615, 616) have ID data of a specific IC. Therefore, it is indicated that the data is sent to a specific IC among a plurality of electrodes. As shown in FIG. 6, all the ICs receive the same data through one wire, but only one IC having the same ID among them processes the data. The IC that receives the data outputs the measured temperature and impedance information through the packet 614 to the outside in the next section. Therefore, the data that the MCU sends to each IC and the data that each IC sends to the MCU are sequentially transmitted through one wire without overlap or blank.

7 is a diagram for explaining a frequency and phase synchronization check process according to an embodiment of the present invention.

In order to perform data communication, clock and data recovery (CDR) circuits are required because the frequency and phase information of the data to be transmitted and received must match. The CDR circuit requires a certain amount of time for frequency and phase synchronization, and the loss of lock detector (LOL) block included therein monitors the synchronization status in real time. Therefore, it is necessary to check the synchronization information from the LOL before starting data communication Is required. The MCU sequentially sends data to each IC to see if it has been synchronized, and the IC extracts the frequency and phase information from the data. When synchronization is complete, each IC informs the MCU that synchronization is complete. The synchronization completion timing may be different for each IC, and the MCU starts data communication for the operation after confirming that all ICs are synchronized.

8 is a diagram showing a result of a data communication simulation according to an embodiment of the present invention.

The data sent from the transmitter (TX) of the MCU is transmitted to the receiver (RX) of IC1 and IC2 in common. However, each IC first analyzes the ID data and processes only the data sent to it. The data sent from the TX of each IC is sequentially transmitted to the RX of the MCU, and one-to-many bi-directional communication is possible through one data line.

9 is a diagram illustrating a clock and data restoring circuit structure according to an embodiment of the present invention.

In general, the CDR circuit requires an external reference clock. However, in the present invention, a structure for synchronizing the frequency and the phase without using the reference clock is used to minimize the number of externally connected wires. The update information of a phase detector (BBPD) and a frequency detector (FD) controls a voltage controlled oscillator (VCO) through a digital loop filter (DLF) . For example, a VCO may have three control paths. The finest control path is converted to a thermometer code to minimize the glitch (DSM: Delta-sigma modulation) and then to an analog voltage .

10 is a view for explaining the principle of a counter based frequency detector according to an embodiment of the present invention.

Generally, in order to extract frequency information from data without reference clock, data must be input continuously. Therefore, it is difficult to use the conventional method as it is in the present invention in which bidirectional communication is performed using one wire. On the other hand, since the present invention performs data communication using the time division method, the period for receiving input data and the period for outputting output data are always constant. Therefore, if the start bit and the end bit of the input data are set to 1 and the output interval is set to 0 by using a pull down resistor, a continuous interval that is always constant as shown in FIG. 10 can be formed. This continuous interval is counted using the frequency divided VCO clock and compared with the ideal value to determine whether the current VCO frequency is faster or slower than the frequency of the input data.

FIG. 11 is a diagram showing simulation results of a 3D finite element solver according to an embodiment of the present invention.

In RF (Radio Frequency) ablation method in which AC high frequency energy is passed through the body to remove the nerve, current density and energy concentration are determined according to the area of the electrode. Therefore, depending on the contact state of the patch-shaped electrode attached to the outside of the body, a skin image may be applied, and an AC signal flowing into the body may interfere with other monitoring equipment. In addition, in order to use a multiplexing scheme in which multiple electrodes are controlled by one electric wire, an AC control switch must be implemented inside the IC. However, high-voltage AC switches are inefficient to implement in ICs because they have many areas. Therefore, in the present invention, a direct heating method is used in which heat is directly transmitted to the IC. The temperature of the IC increases in proportion to the power consumed. Therefore, the power consumption of the heater circuit built in the IC is controlled according to the input.

11 is a simulation result of a temperature change according to the IC power consumption through a 3D finite element solver. When the heater circuit inside the IC consumes a certain amount of electric power, the temperature of the electrode gradually increases at a temperature of 36.5 ° C., but it does not increase any more due to the cooling action of the flowing blood. Simulation can be used to predict the amount of power that must be consumed to heat the vessel wall to the desired temperature.

12 is a diagram showing the structure of a heater circuit according to an embodiment of the present invention.

The proposed heater circuit includes a plurality of resistors capable of generating heat, MOSFET switches for controlling the same, and a PWM pulse generating circuit (Heater_PWM Controller). For example, four heater circuits consuming up to 1.25W of power can be evenly distributed inside the IC to consume up to 5W of power. The 9-bit data received from the MCU is converted into PWM pulses and the MOSFET switches are controlled in parallel through the driver circuit (DRV). The relationship between the consumed power and the duty cycle of the PWM pulse is as follows.

13 is a diagram showing a simulation result of a PWM control circuit according to an embodiment of the present invention.

According to an embodiment of the present invention, a PWM pulse is formed based on a falling edge of the last bit of the received data, and the period of the pulse is data / (8 x 62.5 kHz).

14 is a diagram illustrating a bandgap reference circuit according to an embodiment of the present invention.

The entire heating mechanism consists of a feedback system using temperature information. In order to block the nerve of the renal artery wall, a proper temperature should be maintained for a certain period of time. Generally, about 60 to 70 degrees for about 1 minute can be heated to create the desired degree of lesion. Too high a temperature causes carbonization of the arterial lining layer, and too little temperature can lead to nerve resection. To maintain a constant temperature, the feedback system compares the constant reference temperature with the temperature information obtained through the temperature sensor to increase the power if the temperature of the vessel wall is lower and, if higher, to reduce it to the desired reference temperature. For such a voice feedback system, a temperature sensor for sensing temperature information is required.

The on-chip temperature sensor of the present invention mainly uses characteristics of various parameters of the MOSFET or BJT depending on the temperature. Among the various methods for sensing the temperature information, there is a method using the voltage generated in the bandgap so that the absolute value thereof can be predicted in advance. 14 is a circuit for generating a bandgap reference voltage. For example, if the slope of the constant proportional to absolute temperature (IAT) current and the constantly decreasing CTAT (complementary to absolute temperature) (I4) current are constant, It is flowed into a resistor to make a voltage (I5) with no change according to the temperature. In the case of a temperature sensor based on such a bandgap circuit, the temperature is sensed by using a characteristic that varies depending on the temperature of PTAT or CTAT.

15 is a view showing a result of a temperature sensor simulation according to an embodiment of the present invention.

It can be seen that the band gap voltage according to an embodiment of the present invention exhibits a minute voltage change of about 0.7 mV according to the temperature change and the output voltage of the temperature sensor is constantly decreased between 30 and 120 degrees.

16 is a diagram illustrating an impedance sensing process according to an embodiment of the present invention.

Impedance information is used as a criterion for determining whether contact between the electrode and the blood vessel wall tissue has been effectively performed. As the vessel wall tissue is heated normally, a temperature-dependent decrease in the electrical impedance occurs and an abrupt increase in impedance becomes a sign of tissue carbonation or clot formation. Observing the impedance of the tissue surface is therefore necessary as it is the process of obtaining information about the state of the procedure between the electrode and the surface. Impedance can be measured by applying a voltage to a current loop consisting of a patch attached to the thigh, an electrode in contact with the blood vessel wall, and a human body, reading the current, applying current, and reading the voltage change. In the embodiment of the present invention, any known current is applied and the absolute value of the voltage change is sensed to measure the impedance.

The maximum permissible current that can be applied to the human body for measurement purposes is 100uAp-p, and the frequency is limited to 1MHz by the medical regulations (IEC60601-1). Therefore, in order to measure the voltage by flowing a sinusoidal current of 100 uAp-p at 500 kHz to the human body, the sinusoidal voltage is converted into a current after generation in the embodiment of the present invention. A sine voltage with a low frequency of 500 kHz generates a sine wave using a digital logic (Digital Logic), a direct digital synthesizer (DDS) method using a DAC and an LPF, since the sine voltage having a low frequency of 500 kHz occupies a large area when it is generated as a passive element. Since the DDS method uses a lookup table, it can be seen that the digitally filtered value is input to the DAC. Therefore, only low-pass filtering of the quantization noise when changing from a digital value to an analog value results in a neat sine wave with no noise removed. In the embodiment of the present invention, sampling was performed using a clock of 16 MHz, and a 5-bit lookup table and a 5-bit DAC were used. To reduce glitches in the transition of each bit, the DAC uses a thermometer code rather than a binary code.

17 is a view showing an alternating current application circuit according to an embodiment of the present invention.

According to one embodiment of the present invention, a voltage-current converter is used to convert the sine voltage of 500 KHz generated in the DDS into a current. The maximum allowable DC current to be applied to the human body is determined by the medical regulations (IEC60601-1), which is 10uA. To meet this requirement, a negative supply and a DC servo loop are used to generate an alternating current Respectively. To prevent DC current from flowing into the human body, the patch voltage corresponding to the ground and the output voltage of the voltage-current converter should be the same. Therefore, the circuit is driven using 0.9V and -0.9V, and the intermediate value of 0V is designed as a common voltage of the output voltage. In addition, a DC servo loop is required for the output node to follow the patch voltage because the DC current can flow to the human body due to a miss match, a change in the supply voltage, and a change in the patch voltage. The DC servo loop is an audio feedback loop with an Op-amp with a high DC gain and a relatively low frequency gain. The DC current is filtered and only the sine current of 500 kHz flows into the human body.

18 is a diagram showing a simulation result of an AC current applying circuit according to an embodiment of the present invention.

18 (a) shows an open loop AC response of a DC servo loop, and FIG. 18 (b) shows a closed loop AC response of a DC servo loop. AC response).

19 is a diagram illustrating a PGA circuit according to an embodiment of the present invention.

According to one embodiment of the present invention, a voltage value that allows current to flow through an electrode contacting the arterial wall to read impedance is read. At this time, the approximate contact impedance value decreases from 100Ω to 200Ω as it is heated at 300Ω. According to medical regulations, the alternating current that can be applied to the human body is 100uAp-p, so a contact voltage of 30mVp-p appears at the contact due to the known contact impedance. This voltage value is very small to be processed by an ADC with full range of 1V, so amplification is required. Therefore, the C2C PGA (Cap to Cap Programmable Gain Amplifier) is designed with a maximum gain of 29dB and digital control with 6bit. Since the input signal does not have a bandwidth and is a tone of 500 kHz, only the gain at 500 kHz is guaranteed, so it is not necessary to set the low 3dB corner low. Therefore, it is set at about 23 kHz. In addition, the high 3 dB corner does not receive high frequency noise, and the PVT variation is set to 1.23 MHz with a margin to ensure a designed gain at 500 kHz.

20 is a block diagram of a peak detector according to an embodiment of the present invention.

FIG. 20A is a diagram showing the structure of a peak-to-peak detector, and FIG. 20B is a diagram showing an operation principle of a peak-to-peak detector.

Impedance consists of magnitude and phase. In renal artery nerve excision, only magnitude information of impedance is needed. Therefore, only peak to peak information of AC voltage is needed to measure impedance magnitude. Therefore, a Peak to Peak Detector is needed to read the peak-to-peak information of the AC voltage amplified at the output of the C2C PGA in the ADC. 20 shows the structure and operation principle of a peak-to-peak detector. The input S / H (Sample and Hold) circuit holds the input every clock cycle and the comparator compares the input to the held input. The result of the comparator is inverted at the peak and the maximum value of the input, that is, the value at that time is sampled to obtain a peak value.

FIG. 21 is a diagram showing a simulation result of a peak detector according to an embodiment of the present invention. FIG.

According to an embodiment of the present invention, since a peak value with a small error can be obtained as the sampling clock speed becomes high, 16 MHz, which is the fastest clock in the chip, is used. The clock is also synchronized with the input signal to reduce the gain error.

22 is a diagram illustrating a shared analog-to-digital converter (ADC) according to an embodiment of the present invention.

In order to transmit the temperature and impedance information sensed by the IC to an external power generator using noise-resistant digital communication, an analog-to-digital converter for converting analog information to digital is needed. For example, since the ADC must be as small as possible for the IC design to enter into the kidney artery having a diameter of approximately 5 mm, the present invention proposes a circuit for sharing two ADCs in real time by sharing one ADC as shown in FIG. . The reason for this sharing of ADCs is that the temperature and impedance changes are very slow compared to the ADC's operating speed, so there is less information to lose even if the data sampling rate is slower.

The apparatus described above may be implemented as a hardware component, a software component, and / or a combination of hardware components and software components. For example, the apparatus and components described in the embodiments may be implemented within a computer system, such as, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable array (FPA) A programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. The processing device may also access, store, manipulate, process, and generate data in response to execution of the software. For ease of understanding, the processing apparatus may be described as being used singly, but those skilled in the art will recognize that the processing apparatus may have a plurality of processing elements and / As shown in FIG. For example, the processing unit may comprise a plurality of processors or one processor and one controller. Other processing configurations are also possible, such as a parallel processor.

The software may include a computer program, code, instructions, or a combination of one or more of the foregoing, and may be configured to configure the processing device to operate as desired or to process it collectively or collectively Device can be commanded. The software and / or data may be in the form of any type of machine, component, physical device, virtual equipment, computer storage media, or device , Or may be permanently or temporarily embodied in a transmitted signal wave. The software may be distributed over a networked computer system and stored or executed in a distributed manner. The software and data may be stored on one or more computer readable recording media.

The method according to an embodiment may be implemented in the form of a program command that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions to be recorded on the medium may be those specially designed and configured for the embodiments or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. For example, it is to be understood that the techniques described may be performed in a different order than the described methods, and / or that components of the described systems, structures, devices, circuits, Lt; / RTI > or equivalents, even if it is replaced or replaced.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

Claims

An integrated circuit for a multi-electrode nephronectomy system,
A regulator for generating and supplying a plurality of voltages required by each block inside the integrated circuit using a supply voltage supplied from a power generator through a VDD line;
A communication unit that receives control data for controlling the temperature of a plurality of electrodes from the power generator, and transmits temperature information and impedance information to the power generator sequentially in time according to a TDMA scheme;
A temperature sensor for measuring the temperature using a current that increases in proportion to the temperature inside the bandgap reference circuit; And
An impedance sensor for measuring an impedance by applying a predetermined current and sensing an absolute value of a voltage change;
A shared ADC for digitizing the temperature information measured by the temperature sensor and the impedance information measured by the impedance sensor; And
A heater for adjusting the temperature by controlling the consumed electric power by using the control data received from the power generator
Lt; / RTI >
The shared ADC,
A shared ADC is used to convert the temperature information and the impedance information together in real time,
The integrated circuit comprising:
And a control unit for controlling the temperature of the plurality of electrodes through a single wire from the power generator, the control data being sequentially received at predetermined time intervals,
Digitizing the measured information using the integrated circuit and transmitting it to the power generator via the single wire
Wherein the integrated circuit comprises a plurality of electrodes.

The method according to claim 1,
The heater
The control data received from the power generator is converted into a PWM pulse through a PWM pulse generation circuit and a plurality of MOSFET switches are controlled in parallel using the PWM pulse through a driver circuit to control the power consumption of the resistance of the heater To do
Wherein the integrated circuit comprises a plurality of electrodes.

3. The method of claim 2,
And controlling the consumption power of the resistor of the heater to transfer heat directly to the blood vessel wall through the electrode
Wherein the integrated circuit comprises a plurality of electrodes.

The method according to claim 1,
Wherein the temperature sensor comprises:
The heater is used to increase the supply current amount of the heater when the measured temperature is lower than the target temperature and to reduce the supply current amount of the heater when the measured temperature is higher than the target temperature
Wherein the integrated circuit comprises a plurality of electrodes.

The method according to claim 1,
The impedance sensor includes:
A digital sine wave generator for generating a voltage of a sine wave using the DDS scheme;
An AC current applying circuit for converting the voltage of the generated sinusoidal wave into a current and applying an AC current to the electrode;
A PGA for amplifying an AC voltage by an AC current applied to the electrode to measure an impedance; And
A peak detector for detecting peak-to-peak information of the amplified AC voltage;
Gt; a < / RTI > multiple electrode nephronectomy system.

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The method according to claim 1,
The integrated circuit comprising:
Connected to the power generator using a VDD line, a GND line, and a data line for data communication for supplying the supply voltage
Wherein the integrated circuit comprises a plurality of electrodes.

A method of driving an integrated circuit for a multi-electrode neurotization system,
Generating and supplying a plurality of voltages required by each block inside the integrated circuit through a regulator using a supply voltage supplied from a power generator through a VDD line;
Sensing a temperature proportional current in a bandgap reference circuit of the temperature sensor and measuring the temperature;
Measuring an impedance by applying a predetermined current through an impedance sensor and sensing an absolute value of a voltage change;
Digitizing the temperature information measured by the temperature sensor and the impedance information measured by the impedance sensor through a shared ADC;
Transmitting the temperature information and the impedance information to the power generator sequentially in time according to a TDMA scheme; And
Adjusting the temperature by controlling the power consumption of the heater using control data for adjusting the temperature of the plurality of electrodes received from the power generator according to the temperature information and the impedance information
Lt; / RTI >
The step of digitizing the temperature information measured by the temperature sensor through the shared ADC and the impedance information measured by the impedance sensor,
A shared ADC is used to convert the temperature information and the impedance information together in real time,
A method of driving an integrated circuit for a multi-electrode neurotization system,
The control data for adjusting the temperature of the plurality of electrodes through a single wire from the power generator sequentially at predetermined time intervals,
Digitizing the measured information using the integrated circuit and transmitting it to the power generator via the single wire
Wherein the method comprises the steps of:

10. The method of claim 9,
Sensing the temperature proportional current in the band gap reference circuit of the temperature sensor and measuring the temperature,
Increasing the supply current amount of the heater when the measured temperature is lower than the target temperature and decreasing the supply current amount of the heater when the measured temperature is higher than the target temperature
Wherein the method comprises the steps of:

10. The method of claim 9,
The step of measuring the impedance by applying a predetermined current through the impedance sensor and sensing the absolute value of the voltage change,
A voltage of a sinusoidal wave is generated by using the DDS method, a voltage of the generated sinusoidal wave is converted into a current to apply an alternating current to the electrode, and an alternating voltage by the alternating current applied to the electrode is amplified To detect peak-to-peak information of the amplified AC voltage
Wherein the method comprises the steps of:

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10. The method of claim 9,
Wherein the step of controlling the temperature by controlling the power consumption of the heater using the control data for adjusting the temperature of the plurality of electrodes received from the power generator according to the temperature information and the impedance information,
The control data received from the power generator is converted into a PWM pulse through a PWM pulse generation circuit and a plurality of MOSFET switches are controlled in parallel using the PWM pulse through a driver circuit to control the power consumption of the resistance of the heater To do
Wherein the method comprises the steps of:

14. The method of claim 13,
And controlling the consumption power of the resistor to transfer heat directly to the blood vessel wall through the electrode
Wherein the method comprises the steps of:

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