ISFET-based single-chip integrated miniature wireless pH detection device and system

Abstract

This application discloses a single-chip integrated miniature wireless pH detection device and system based on ISFET, relating to the field of in vivo pH detection technology. The device includes: a housing; a wireless sensing chip integrating a pH sensing module, the sensing interface of which is exposed to the measured environment through the housing; a signal processing module connected to the pH sensing module for processing the pH sensing signal detected by the pH sensing module; and a wireless communication and power supply module connected to the signal processing module for transmitting the pH sensing signal processed by the signal processing module and supplying power to the modules on the wireless sensing chip. This application integrates the pH detection module, signal processing module, and wireless communication module into a single on-chip system, utilizing CMOS technology, wireless power transfer technology, and backscattered reverse communication technology, effectively reducing the size of the pH detection device and improving the accuracy of pH detection.

Description

Technical Field

[0001] This application relates to the field of in vivo pH detection technology, specifically to a single-chip integrated micro wireless pH detection device and system based on ISFET. Background Technology

[0002] Gastroesophageal reflux disease (GERD) is a condition in which stomach contents reflux into the esophagus or pharynx, causing a series of intraesophageal and extraesophageal symptoms and related complications. Currently, 24-hour pH monitoring is widely considered the gold standard for diagnosing GERD. The core step in the monitoring process involves placing a pH electrode approximately 5 cm above the esophageal sphincter. The collected data is then transmitted to an external analyzer for clinical analysis. Considering that this data acquisition process is performed in vivo and under strict medical hygiene standards, the ideal electrode for monitoring pH levels inside the esophagus should be miniature, reliable, and economical.

[0003] However, to date, the most widely used and technologically mature pH monitoring systems in the medical market are all based on catheter-based insertable electrodes, which have many limitations. For example, the position of the catheter electrode changes with changes in patient position and swallowing, leading to inaccurate measurement data; during long-term testing, the pH value of the catheter electrode slowly drifts over time due to oxidation of the electrode surface. Therefore, after a certain period of time, the accuracy of data obtained using catheter electrodes will decrease, affecting the diagnostic rate; and the catheter insertion method can be uncomfortable for the patient.

[0004] In addition, there is a wireless implantable pH monitoring capsule on the medical market, such as the BRAVO Capsule. This capsule's wireless detection system is implemented by a combination of multiple functional modules, requiring complex electrical connections between them. This results in a relatively large capsule size, making implantation and fixation difficult. Furthermore, prolonged monitoring can lead to oxidative damage to the electrodes, short battery life, and spontaneous detachment. Moreover, due to the low sampling frequency of the wireless monitoring system, the BRAVO system lacks sensitivity to short-term reflux events (<15s to 17s), potentially causing data loss. Summary of the Invention

[0005] In order to solve at least one of the above-mentioned problems in the prior art, embodiments of this application provide a single-chip integrated micro wireless pH detection device and system based on ISFET.

[0006] According to a first aspect of the embodiments of this application, this application provides a single-chip integrated miniature wireless pH detection device based on ISFET, the device comprising:

[0007] shell;

[0008] A wireless sensor chip, on which the following are integrated:

[0009] A pH sensing module, the sensing interface of which is exposed to the measured environment through the housing;

[0010] A signal processing module, connected to the pH sensing module, is used to process the pH sensing signal detected by the pH sensing module; and

[0011] A wireless communication and power supply module is connected to the signal processing module and is used to send the PH sensing signal processed by the signal processing module and to supply power to each module on the wireless sensing chip.

[0012] In one embodiment, the pH sensing module employs an ion-sensitive field-effect transistor;

[0013] The reference electrode of the ion-sensitive field-effect transistor is integrated onto the chip using CMOS technology.

[0014] In one embodiment, the reference electrode is formed on the chip using magnetron sputtering, electron evaporation, or electroplating techniques.

[0015] In one embodiment, the sensing interface includes an ion-sensitive medium layer;

[0016] The ion-sensitive dielectric layer includes one of silicon oxide, silicon nitride, high-K dielectric material, and hydrogen ion-sensitive metal oxide.

[0017] In one embodiment, the signal processing module includes:

[0018] The power amplifier unit is used to amplify the pH sensing signal;

[0019] The analog-to-digital conversion unit is used to perform analog-to-digital conversion on the pH sensing signal amplified by the power amplifier unit.

[0020] In one embodiment, the wireless communication and power supply module includes:

[0021] A load modulation keying circuit, connected to the signal processing module, is used to transmit the PH sensing signal processed by the signal processing module;

[0022] An on-chip coil, connected to the load modulation keying circuit, is used to change the load according to the regulation of the load modulation keying circuit, so as to send the PH sensing signal or receive an external power signal.

[0023] An on-chip power management module is connected to the signal processing module and the pH sensing module respectively, and is used to convert the power signal into a DC power supply voltage for power supply.

[0024] In one embodiment, the load modulation keying circuit is further configured to:

[0025] Upon receiving the pH sensing signal sent by the signal processing module, the load change of the on-chip coil is controlled according to the pH sensing signal, so that the on-chip coil sends the pH sensing signal.

[0026] When no PH sensing signal is received from the signal processing module, the load change of the on-chip coil is controlled according to the power signal so that the on-chip coil receives the power signal.

[0027] In one embodiment, the on-chip power management module includes:

[0028] The on-chip rectifier circuit and on-chip voltage regulator circuit are used to convert the power signal into a stable DC power supply voltage.

[0029] In one embodiment, the housing is made of a material that is resistant to corrosion from substances in the tested environment.

[0030] According to a second aspect of the embodiments of this application, this application provides a single-chip integrated miniature wireless pH detection system based on ISFET, the system comprising:

[0031] The ISFET-based single-chip integrated miniature wireless pH detection device provided in any embodiment of this application is placed in the environment to be tested;

[0032] The wireless transceiver is placed in a signal receiving environment that is different from the environment under test.

[0033] The ISFET-based single-chip integrated miniature wireless pH detection device detects the pH signal in the tested environment and sends the pH signal to the wireless transceiver; it also receives the power signal transmitted by the wireless transceiver and converts the power signal into a DC power supply voltage.

[0034] This application discloses a single-chip integrated miniature wireless pH detection device and system based on ISFET. Utilizing an ISFET-based pH sensing circuit, the system integrates a sensor and on-chip reference electrode through microfabrication, reducing the gastric acid monitoring chip system size to the millimeter level. This enables seamless implantation and facilitates efficient, accurate, reliable, and rapid diagnostic processes. Furthermore, the implantable system, powered by a wireless power transmission system, further reduces power consumption and enhances safety and reliability through a mid-to-far field power transmission system, a low-power power management system, and a backscattered reverse communication system. Moreover, the inherent semiconductor properties of the ISFET biochip allow for easy integration of core functions and signal processing onto a single on-chip system, resulting in a novel, miniaturized, highly accurate, and reliable medical diagnostic system. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0036] Figure 1 A side cross-sectional view of the ISFET-based single-chip integrated micro wireless pH detection device provided in this application.

[0037] Figure 2 A system structure block diagram of the wireless sensor chip provided in this application.

[0038] Figure 3 Another system architecture block diagram of the wireless sensing chip provided in this application.

[0039] Figure 4 Another system architecture block diagram of the wireless sensing chip provided in this application.

[0040] Figure 5 A schematic diagram of the ISFET-based single-chip integrated micro wireless pH detection system provided in this application. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0042] According to a first aspect of the embodiments of this application, this application provides a single-chip integrated miniature wireless pH detection device based on ISFET. Figure 1 This is a side cross-sectional view of the ISFET-based single-chip integrated miniature wireless pH detection device. Figure 2 This is a system architecture block diagram for a wireless sensor chip. (Example:) Figure 1 As shown, the device includes: a housing 1 and a wireless sensor chip 2. Figure 2 As shown, the wireless sensor chip 2 integrates a pH sensor module 3, a signal processing module 4, and a wireless communication and power supply module 5.

[0043] The pH sensor module 3 includes a sensing interface and a sensing circuit. For example... Figure 1 As shown, the sensing interface 31 is exposed to the measured environment through the opening 11 of the housing 1, and is in direct contact with the liquid in the measured environment to obtain the pH signal of the measured environment. Except for the sensing interface 31, the rest of the wireless sensing chip 2 is sealed inside the housing 1 and does not come into contact with the substances in the measured environment.

[0044] When using the ISFET-based single-chip integrated miniature wireless pH detection device of this application, it is fixed in the test environment 6, such as the human esophagus. The housing 1 and sensing interface 31 of the ISFET-based single-chip integrated miniature wireless pH detection device are exposed to the test environment, while the rest of the wireless sensing chip 2 is protected by the housing 1 and will not be corroded by substances in the test environment. The housing 1 is made of a material resistant to corrosion by substances in the test environment. For example, if the test environment is the human esophagus, the housing 1 should be made of a material resistant to gastric acid corrosion and non-toxic to the human body.

[0045] The sensing interface 31 of the pH sensing module 3 comes into contact with the substance in the measured environment, and the sensing circuit detects the pH sensing signal. The signal processing module 4 is connected to the pH sensing module 3 and is used to process the pH sensing signal detected by the pH sensing module 3. The wireless communication and power supply module 5 is connected to the signal processing module 4 and is used to send the pH sensing signal processed by the signal processing module 4 to an external device, and to receive the power signal sent by the external device and convert the power signal into DC power to power the various modules of the wireless sensing chip 2. The external device that receives the pH sensing signal and the external device that sends the power signal can be the same device or different devices; this application does not limit this.

[0046] In this application, the integration of the pH sensing module 3, signal processing module 4, and wireless communication and power supply module 5 onto the wireless sensing chip 2 can be achieved using CMOS technology. Since all modules are integrated onto the same chip, the size of the ISFET-based single-chip integrated miniature wireless pH detection device can be effectively reduced. When implanted in the human body, this helps alleviate discomfort and provides a more comfortable medical experience. Simultaneously, the wireless communication and power supply module 5 employs wireless power transfer technology and backscattering technology for communication and power supply. Because communication and power supply share the same channel, the number of communication coils is reduced, further improving the device's integration and lowering data transmission power consumption.

[0047] In one embodiment, the pH sensing module 2 uses an ion-sensitive field-effect transistor (ISFET); and the reference electrode of the ISFET is integrated onto the wireless sensing chip 2 using CMOS technology.

[0048] Traditional ISFETs require an external reference electrode to provide a stable potential for the measured environment. External reference electrodes are relatively large, typically on the order of millimeters (mm) or centimeters (cm). This application achieves on-chip integration of the ISFET reference electrode using CMOS technology, integrating the reference electrode onto the wireless sensor chip 2. Since an external reference electrode is unnecessary, this application significantly reduces the overall size of the single-chip integrated miniature wireless pH detection device based on ISFETs.

[0049] This structure allows for the simultaneous design of the reference electrode as part of the wireless sensor chip 2 using CMOS technology. The reference electrode is then formed on the wireless sensor chip using techniques such as magnetron sputtering, electron evaporation, or electroplating. This enables on-chip control of the reference electrode area and fixation of the distance between the reference electrode and the sensing front end, significantly improving the sensitivity and accuracy of the detection system. Simultaneously, the size of the reference electrode is significantly reduced, and since the reference electrode and sensing circuit are on the same plane, the overall size of the ISFET-based single-chip integrated miniature wireless pH detection device can be effectively reduced.

[0050] Taking the Ag / AgCl reference electrode as an example, when fabricating an on-chip reference electrode, a designated area of ​​the reference electrode on the chip can be designed using CMOS technology. Then, silver (Ag) material is sputtered onto the designated area on the chip using magnetron sputtering, electronic evaporation, or electroplating techniques. The thickness of the silver material can be adjusted as needed, generally at the μm level. Subsequently, AgCl is generated on the Ag surface through an electrode reaction with HCl, thereby realizing the fabrication of the on-chip reference electrode.

[0051] In one embodiment, the sensing interface includes an ion-sensitive medium layer;

[0052] The ion-sensitive dielectric layer includes, but is not limited to, one of silicon oxide, silicon nitride, tantalum oxide, aluminum oxide, high-K dielectric materials, and hydrogen ion-sensitive metal oxides. In practical applications, the appropriate type of ion-sensitive dielectric layer material can be selected according to the operating frequency requirements of the application scenario.

[0053] This application does not limit the process or technology used to form the ion-sensitive dielectric layer. The process or technology used in growing the ion-sensitive dielectric layer at the sensing interface can vary depending on the material of the ion-sensitive dielectric layer. For example, for silicon oxide and silicon nitride, growth can be achieved using CMOS processes; for high-K dielectrics and hydrogen ion-sensitive metal oxides, deposition or other processes can be used. In practical applications, any suitable process or technology can be selected, and this application does not impose any restrictions on it.

[0054] In one embodiment, such as Figure 3 As shown, signal processing module 4 includes:

[0055] Power amplifier unit 41 is used to amplify the pH sensing signal;

[0056] The analog-to-digital conversion unit 42 is used to perform analog-to-digital conversion on the PH sensing signal amplified by the power amplifier unit.

[0057] Among them, the power amplifier unit 41 and the analog-to-digital conversion unit 42 can adopt an extremely low power consumption design. For example, the power consumption requirements of the signal processing module can be reduced from the perspective of architecture and working mode. At the same time, ultra-low power digital units can also be used in the design to further meet the power supply scheme and low power consumption requirements of the entire device.

[0058] In one embodiment, such as Figure 4 As shown, the wireless communication and power supply module 5 includes;

[0059] The load shift keying (LSK) circuit 51 is connected to the signal processing module 4 and is used to transmit the PH sensing signal processed by the signal processing module 4.

[0060] An on-chip coil 52 is connected to a load modulation keying circuit 51 and is used to change the load according to the regulation of the load modulation keying circuit 51 in order to send a pH sensing signal or receive an external power signal.

[0061] The on-chip power management module 53 is connected to the signal processing module 4 and the pH sensing module 3 respectively, and is used to convert the power signal received by the on-chip coil 52 into a DC power supply voltage for power supply.

[0062] When the load modulation keying circuit 51 receives the PH sensing signal sent by the signal processing module, it controls the load change of the on-chip coil 52 according to the PH sensing signal, so that the on-chip coil 52 sends the PH sensing signal and realizes the wireless communication function.

[0063] When the load modulation keying circuit 51 does not receive the PH sensing signal sent by the signal processing module, it controls the load change of the on-chip coil 52 according to the power signal so that the on-chip coil receives the power signal sent by the external device. The on-chip power management module 53 then converts the power signal into a DC power supply voltage for power supply, thereby realizing the wireless power supply function.

[0064] Taking the on-chip coil 52 transmitting and receiving binary signals as an example, assume that the load of the on-chip coil 52 can vary between 0 and R according to the control of the load modulation keying circuit 51. Simultaneously, it is preset that when the load of the on-chip coil 52 is a first load value, it is equivalent to transmitting the digital signal "1", and when the load of the on-chip coil 52 is a second load value b, it is equivalent to transmitting the digital signal "0". The first load value a and the second load value b satisfy: 0 ≤ a ≤ R, 0 ≤ b ≤ R, a ≠ b, and the difference between the first load value a and the second load value b is greater than a preset threshold x, where 0 ≤ x ≤ R. In practical applications, the setting of x should ensure that a and b can be clearly distinguished.

[0065] When the pH sensor module 3 detects a pH sensor signal, the wireless communication implementation process is as follows:

[0066] (1) The pH sensing module 3 detects the pH sensing signal and sends it to the signal processing module 4; at this time, the pH sensing signal is an analog signal, so it can also be called the pH sensing analog signal.

[0067] (2) The signal processing module 4 amplifies and converts the PH sensing analog signal to digital and sends it to the load modulation keying circuit 51. The PH sensing signal processed by the signal processing module 4 is a digital signal, so it can also be called the PH sensing digital signal.

[0068] (3) After receiving the PH sensing digital signal, the load modulation keying circuit 51 transmits it to the on-chip coil 52. At the same time, the load modulation keying circuit 51 adjusts the load of the on-chip coil 52 according to the PH sensing digital signal, and controls the load value of the load to continuously change to the first load value a corresponding to the binary number "1" or the second load value b corresponding to the binary number "0".

[0069] At this point, whether the load changes to the first load value 'a' or the second load value 'b' is determined based on the pH sensor digital signal. For example, assuming a detected pH sensor digital signal is 0111001..., the load modulation keying circuit 51 controls the load value to change sequentially to b, a, a, a, b, b, a... It can be understood that as the measured environment changes or the contents within the measured environment change, the pH sensor signal detected by the pH sensor module 3 will also change; that is, the pH sensor signal detected by the pH sensor module each time may be the same or different. The load modulation keying circuit 51 controls the load value differently when it receives different pH sensor signals.

[0070] The load modulation keying circuit 51 controls the load to switch back and forth between the first load value a and the second load value b according to the PH sensing digital signal, thereby enabling the on-chip coil 53 to send the PH sensing digital signal to an external device (such as an external signal receiving device) outside the measured environment, so that the device outside the measured environment can receive, record, store and analyze the PH environment in the measured environment, thus realizing the wireless communication function of the PH sensing signal.

[0071] When the pH sensing module 3 does not detect a pH sensing signal, that is, when the load modulation keying circuit 51 does not receive a pH sensing signal, the wireless power supply implementation process is as follows:

[0072] (1) A power signal transmitted by an external device (e.g., an external signal transmitting device) outside the measured environment, the power signal being, for example, a sinusoidal signal of a specific frequency.

[0073] (2) The load modulation keying circuit 51 adjusts the load of the on-chip coil 52 according to the preset control mode corresponding to the power signal, and controls the load value of the load to continuously change to the first load value a corresponding to the binary number "1" or the second load value b corresponding to the binary number "0".

[0074] At this time, the control mode of the load modulation keying circuit 51 corresponds to the power signal. For example, assuming the power signal is 01010101…, the load modulation keying circuit 51 controls the load to change sequentially to b, a, b, a, b, a, b, a… It can be understood that, in order to ensure the realization of the wireless power supply function, the power signal in this application is a pre-set fixed signal. At the same time, the control mode of the load modulation keying circuit 51 on the load when it does not receive the PH sensor signal is set to a fixed control mode corresponding to the fixed signal. Alternatively, the power signal in this application can be changed, but while changing the power signal, the control mode of the load modulation keying circuit 51 on the load when it does not receive the PH sensor signal must be changed accordingly.

[0075] The load modulation keying circuit 51 controls the load to switch back and forth between the first load value a and the second load value b according to the control mode corresponding to the power signal sent by the external device (e.g., the external signal transmitting device) outside the test environment, which is preset. This enables the on-chip coil 53 to receive the power signal, and the on-chip power management module 53 converts the power signal into a DC power supply voltage for power supply, thus realizing the wireless power supply function based on the power signal.

[0076] In this application, the wireless communication and power supply module 5 uses wireless power transfer technology for power supply and backscattering technology for reverse communication. Since the power supply and communication processes share the same channel, only one coil is needed, thereby further improving the integration of the device and reducing data transmission power consumption. This application uses mid-to-far field wireless power transfer technology to design the wireless communication and power supply module 5. Compared with near-field inductive coupling, the mid-field electromagnetic radiation energy transfer method includes both near-field inductive coupling and part of far-field electromagnetic radiation, resulting in a greater distance between the transmitting and receiving coils and a smaller coil size.

[0077] In one embodiment, the on-chip power management module 53 includes an on-chip rectifier circuit and an on-chip voltage regulator circuit for converting the power signal into a stable DC power supply voltage.

[0078] The on-chip rectifier and on-chip voltage regulator circuits utilize subthreshold operating characteristics and body drive design to operate at lower power supply voltages to match wireless power transfer systems. At the same time, the design without external capacitors and the diode rectifier circuit can improve integration and reduce the size of implantable devices.

[0079] According to a second aspect of the embodiments of this application, this application provides a single-chip integrated miniature wireless pH detection system based on ISFET. Figure 5 This is a schematic diagram of a single-chip integrated miniature wireless pH detection system based on ISFET provided in this application. Figure 5 As shown, the system 100 includes:

[0080] A single-chip integrated miniature wireless pH detection device 101 based on ISFET is placed in the environment to be measured.

[0081] The wireless transceiver 102 is located in a signal receiving environment that is different from the measured environment;

[0082] The ISFET-based single-chip integrated miniature wireless pH detection device 101 detects the pH signal in the tested environment and transmits the pH signal to the wireless transceiver 102. The ISFET-based single-chip integrated miniature wireless pH detection device 101 also receives the power signal transmitted by the wireless transceiver 102 and converts the power signal into a DC power supply voltage. The ISFET-based single-chip integrated miniature wireless pH detection device 101 of this system 100 can be any of the ISFET-based single-chip integrated miniature wireless pH detection devices provided in any embodiment of this application; specific details can be found in the relevant embodiments of this application, which will not be repeated here.

[0083] In practical applications, a tube containing the ISFET-based single-chip integrated miniature wireless pH detection device is inserted into the patient's esophagus, and the device is then secured to the esophagus using a feasible method. The pH sensing module of the ISFET-based single-chip integrated miniature wireless pH detection device monitors the pH value of the surrounding environment in real time, and the signal processing module amplifies and converts the signal to digital. Subsequently, the wireless communication module within the ISFET-based single-chip integrated miniature wireless pH detection device communicates wirelessly with the externally worn communication module of the patient to transmit and record monitoring data, including the amount of gastric acid reflux within the patient's esophagus. After a period of time, the ISFET-based single-chip integrated miniature wireless pH detection device will detach from the esophageal wall tissue and be excreted through the digestive system, completing the monitoring function.

[0084] This application presents a single-chip integrated micro-wireless pH detection system based on ISFET. Employing an ISFET-based pH sensing circuit, the system integrates a sensor and on-chip reference electrode through microfabrication, reducing the gastric acid monitoring chip system size to the millimeter level. This enables seamless implantation and facilitates efficient, accurate, reliable, and rapid diagnostic processes. Furthermore, the implantable system, powered by a wireless power transmission system, utilizes a mid-to-far field power transmission system, a low-power power management system, and a backscattered reverse communication system to further reduce power consumption and enhance safety and reliability. Moreover, the inherent semiconductor properties of the ISFET biochip allow for easy integration of core functions and signal processing onto a single on-chip system, resulting in a novel, miniaturized, highly accurate, and reliable medical diagnostic system.

[0085] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A single-chip integrated miniature wireless pH detection device based on ISFET, characterized in that, The device includes: shell; A wireless sensor chip, on which the following are integrated: A pH sensing module, the sensing interface of which is exposed to the measured environment through the housing; A signal processing module, connected to the pH sensing module, is used to process the pH sensing signal detected by the pH sensing module; and A wireless communication and power supply module, connected to the signal processing module, is used to transmit the pH sensing signal processed by the signal processing module and to supply power to the various modules on the wireless sensing chip. The wireless communication and power supply module includes: A load modulation keying circuit, connected to the signal processing module, is used to transmit the PH sensing signal processed by the signal processing module; An on-chip coil, connected to the load modulation keying circuit, is used to change the load according to the regulation of the load modulation keying circuit, so as to send the PH sensing signal to an external device or receive a power signal sent by an external device. An on-chip power management module is connected to the signal processing module and the pH sensing module respectively, and is used to convert the power signal into a DC power supply voltage for power supply.

2. The ISFET-based single-chip integrated miniature wireless pH detection device according to claim 1, characterized in that, The pH sensing module uses an ion-sensitive field-effect transistor. The reference electrode of the ion-sensitive field-effect transistor is integrated onto the chip using CMOS technology.

3. The ISFET-based single-chip integrated miniature wireless pH detection device according to claim 2, characterized in that, The reference electrode is formed on the chip using magnetron sputtering, electron evaporation, or electroplating techniques.

4. The ISFET-based single-chip integrated miniature wireless pH detection device according to claim 1, characterized in that, The sensing interface includes an ion-sensitive medium layer; The ion-sensitive dielectric layer includes one of silicon oxide, silicon nitride, high-K dielectric material, and hydrogen ion-sensitive metal oxide.

5. The ISFET-based single-chip integrated miniature wireless pH detection device according to claim 1, characterized in that, The signal processing module includes: The power amplifier unit is used to amplify the pH sensing signal; The analog-to-digital conversion unit is used to perform analog-to-digital conversion on the pH sensing signal amplified by the power amplifier unit.

6. The ISFET-based single-chip integrated miniature wireless pH detection device according to claim 1, characterized in that, The load modulation keying circuit is also used for: Upon receiving the pH sensing signal sent by the signal processing module, the load change of the on-chip coil is controlled according to the pH sensing signal, so that the on-chip coil sends the pH sensing signal. When no PH sensing signal is received from the signal processing module, the load change of the on-chip coil is controlled according to the power signal so that the on-chip coil receives the power signal.

7. The ISFET-based single-chip integrated miniature wireless pH detection device according to claim 1, characterized in that, The on-chip power management module includes: The on-chip rectifier circuit and on-chip voltage regulator circuit are used to convert the power signal into a stable DC power supply voltage.

8. The ISFET-based single-chip integrated miniature wireless pH detection device according to claim 1, characterized in that, The outer shell is made of a material that is resistant to corrosion from substances in the tested environment.

9. A single-chip integrated miniature wireless pH detection system based on ISFET, characterized in that, The system includes: The single-chip integrated micro wireless pH detection device based on ISFET according to any one of claims 1 to 8, is placed in the environment to be measured; The wireless transceiver is placed in a signal receiving environment that is different from the environment under test. The ISFET-based single-chip integrated miniature wireless pH detection device detects the pH signal in the tested environment and sends the pH signal to the wireless transceiver; it also receives the power signal transmitted by the wireless transceiver and converts the power signal into a DC power supply voltage.

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