Gatekeeper circuit, processing system, electronic device and anomaly detection method

Abstract

The application provides a watchdog circuit, a processing system, an electronic device and an abnormality detection method, wherein the watchdog circuit comprises: a push-pull circuit, an energy storage integration circuit and a hysteresis comparator; the push-pull circuit is connected with a target to be monitored and the energy storage integration circuit respectively, is configured to amplify a signal input by the target to be monitored, and outputs the amplified signal to the energy storage integration circuit; the energy storage integration circuit is connected with a non-inverting input terminal of the hysteresis comparator, is configured to perform energy storage integration processing on the signal output by the push-pull circuit, and outputs a corresponding integration voltage signal to the hysteresis comparator; and the hysteresis comparator is configured to output a corresponding detection signal according to the integration voltage signal input by the energy storage integration circuit. The technical scheme of the present application can realize the watchdog circuit based on a simple circuit structure, so as to perform abnormality monitoring on the target to be monitored, and can greatly simplify the circuit structure and reduce the cost.

Description

Technical Field

[0001] This invention relates to the field of electronic and electrical technology, and in particular to a watchdog circuit, processing system, electronic device, and anomaly detection method. Background Technology

[0002] In modern electronic devices, chips (such as MCUs, microcontroller units) serve as core components, undertaking critical tasks such as control and computation. However, due to external interference (such as electromagnetic interference, power fluctuations, etc.) or vulnerabilities in the program itself, chip programs may experience "runaway" phenomena, meaning that the program counter value deviates from the normal execution path, causing the chip to fail to function normally according to the predetermined logic.

[0003] Currently, there are two main types of traditional watchdog circuits. One type is software-based watchdogs, which periodically reset the watchdog timer in the program to indicate that the program is running normally. However, this method has limitations; if the program crashes precisely during the code segment resetting the watchdog timer, the watchdog will fail to detect the program anomaly in time, causing it to malfunction. The other type is based on hardware watchdog chips. While these can reliably detect whether the chip is working properly to a certain extent, these dedicated watchdog chips are usually highly integrated, relatively expensive, and less flexible. In cost-sensitive applications, this increases the cost pressure on the product; furthermore, for some specific application requirements, dedicated watchdog chips may not fully meet customized functional requirements.

[0004] Furthermore, whether it's a software watchdog or a hardware watchdog chip, in practical applications, it's often difficult for users to intuitively obtain information about whether the chip has malfunctioned. Often, even if the watchdog detects a chip anomaly, it simply resets the chip, leaving the user unaware that the chip had ever malfunctioned. This fails to meet the user's need for comprehensive control over the system's operational status in applications with extremely high requirements for system stability and reliability, such as industrial control and medical equipment. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art, and proposes a watchdog circuit, a processing system, an electronic device, and an anomaly detection method.

[0006] In a first aspect, this disclosure provides a watchdog circuit, including: a push-pull circuit, an energy storage integrator circuit, and a hysteresis comparator;

[0007] The push-pull circuit is connected to the target to be monitored and the energy storage integration circuit respectively, and is configured to amplify the signal input from the target to be monitored and output the amplified signal to the energy storage integration circuit.

[0008] The energy storage integration circuit is connected to the non-inverting input of the hysteresis comparator and is configured to perform energy storage integration processing on the signal output by the push-pull circuit and output a corresponding integrated voltage signal to the hysteresis comparator.

[0009] The hysteresis comparator is configured to output a corresponding detection signal based on the integrated voltage signal input to the energy storage integrator circuit.

[0010] In some embodiments, the energy storage integration circuit includes: a second resistor and a first capacitor;

[0011] The first end of the second resistor is connected to the push-pull circuit, and the second end of the second resistor is connected to the non-inverting input of the hysteresis comparator and the first end of the first capacitor.

[0012] The second terminal of the first capacitor is connected to the third voltage supply terminal.

[0013] In some embodiments, the energy storage integration circuit further includes: a freewheeling diode;

[0014] The cathode of the freewheeling diode is connected to the first terminal of the second resistor, and the anode of the freewheeling diode is connected to the second terminal of the second resistor.

[0015] In some embodiments, the push-pull circuit includes: a first resistor, an N-type transistor, and a P-type transistor;

[0016] The first end of the first resistor is connected to the target to be monitored, and the second end of the first resistor is connected to the control electrode of both the N-type transistor and the P-type transistor.

[0017] The first terminal of the N-type transistor is connected to the first voltage supply terminal, and the second terminal of the N-type transistor is connected to the energy storage integration circuit.

[0018] The first terminal of the P-type transistor is connected to the second voltage supply terminal, and the second terminal of the P-type transistor is connected to the energy storage integration circuit.

[0019] In some embodiments, the hysteresis comparator includes: a third resistor, a fourth resistor, a fifth resistor, and an operational amplifier;

[0020] The first end of the third resistor is connected to the non-inverting input terminal of the operational amplifier, and the second end of the third resistor is connected to the output terminal of the operational amplifier.

[0021] The first end of the fourth resistor is connected to the first voltage supply terminal, and the second end of the fourth resistor is connected to the inverting input terminal of the operational amplifier.

[0022] The first end of the fifth resistor is connected to the second voltage supply terminal, and the second end of the fifth resistor is connected to the inverting input terminal of the operational amplifier.

[0023] The non-inverting input of the operational amplifier serves as the non-inverting input of the hysteresis comparator, and the output of the operational amplifier serves as the output of the hysteresis comparator.

[0024] In some embodiments, the watchdog circuit further includes: a light-emitting circuit;

[0025] The light-emitting circuit is configured to emit light when the detection signal output by the hysteresis comparator is high, and not emit light when the detection signal output by the hysteresis comparator is low.

[0026] In some embodiments, the light-emitting circuit includes: a light-emitting diode;

[0027] The anode of the light-emitting diode is connected to the output terminal of the hysteresis comparator, and the cathode of the light-emitting diode is connected to the third voltage supply terminal.

[0028] In a second aspect, this disclosure also provides a processing system, including: a processing chip and the watchdog circuit as provided in the first aspect, wherein the target to be monitored is the processing chip.

[0029] Thirdly, this disclosure also provides an electronic device, including: the processing system as described in the second aspect.

[0030] Fourthly, this disclosure also provides an anomaly detection method for a target to be monitored, the anomaly detection method being based on the watchdog circuit provided in the first aspect, the anomaly detection method comprising:

[0031] The push-pull circuit amplifies the signal input from the target to be monitored and outputs the amplified signal to the energy storage integration circuit.

[0032] The energy storage integration circuit performs energy storage integration processing on the signal output by the push-pull circuit and outputs a corresponding integrated voltage signal to the hysteresis comparator.

[0033] The hysteresis comparator outputs a corresponding detection signal based on the integrated voltage signal input to the energy storage integrator circuit. The detection signal can characterize whether the target under monitoring has any operational abnormalities.

[0034] This invention provides a watchdog circuit that amplifies the signal input from the target to be monitored via a push-pull circuit and outputs the amplified signal to an energy storage integrator circuit. The energy storage integrator circuit integrates the signal output from the push-pull circuit and outputs a corresponding integrated voltage signal to a hysteresis comparator. The hysteresis comparator outputs a corresponding detection signal based on the integrated voltage signal input from the energy storage integrator circuit. This detection signal can characterize whether the target to be monitored is malfunctioning. The technical solution of this disclosure can implement a watchdog circuit based on a simple circuit structure for anomaly monitoring of the target, greatly simplifying the circuit structure and reducing costs. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the circuit structure of a watchdog circuit according to an embodiment of the present disclosure;

[0036] Figure 2 This is a timing diagram of the integrated voltage signal and the detection signal when the target to be monitored is working normally in an embodiment of this disclosure;

[0037] Figure 3 This is a timing diagram of the integrated voltage signal and the detection signal when the target to be monitored is malfunctioning in an embodiment of this disclosure;

[0038] Figure 4 This is another timing diagram of the integrated voltage signal and the detection signal when the target to be monitored is malfunctioning in this disclosure;

[0039] Figure 5 This is a schematic diagram of the circuit structure of another watchdog circuit in an embodiment of this disclosure;

[0040] Figure 6 This is a flowchart of an anomaly detection method for a target to be monitored, provided as an embodiment of this disclosure. Detailed Implementation

[0041] To enable those skilled in the art to better understand the technical solutions of this disclosure, the disclosure will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0042] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an,” “a,” or “the,” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “including,” “comprising,” or “containing,” and similar terms mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. The terms “connected,” “linked,” or similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” and “right,” etc., are used only to indicate relative positional relationships, and these relative positional relationships may change accordingly when the absolute position of the described object changes.

[0043] In the various figures, the same elements are represented by similar reference numerals. For clarity, not all parts in the figures are drawn to scale. Furthermore, some well-known parts may not be shown in the figures.

[0044] Many specific details of this disclosure, such as the structure, materials, dimensions, processing methods, and techniques of the components, are described below to provide a clearer understanding of the disclosure. However, as those skilled in the art will understand, this disclosure may be implemented without following these specific details.

[0045] The transistors used in the embodiments of this disclosure can be thin-film transistors, field-effect transistors, or other devices with the same or similar characteristics. Since the source and drain of the transistors used are symmetrical, there is no difference between the source and drain. In this disclosure, one of the two poles (i.e., the source and drain) of the transistor is referred to as the first pole and the other as the second pole, only to distinguish the two poles of the transistor other than the control pole (i.e., the gate).

[0046] For an N-type transistor, it conducts when its gate voltage is high and is cut off when its gate voltage is low; for a P-type transistor, it conducts when its gate voltage is low and is cut off when its gate voltage is high; specific details will not be elaborated here.

[0047] Figure 1 This is a schematic diagram of the circuit structure of a watchdog circuit according to an embodiment of this disclosure. Figure 1 As shown, the watchdog circuit includes: a push-pull circuit 1, an energy storage integrator circuit 2, and a hysteresis comparator 3.

[0048] The push-pull circuit 1 is connected to the target to be monitored and the energy storage integration circuit 2 respectively. The push-pull circuit 1 is configured to amplify the signal input from the target to be monitored and output the amplified signal to the energy storage integration circuit 2.

[0049] The energy storage integrator circuit 2 is connected to the non-inverting input of the hysteresis comparator 3. The energy storage integrator circuit 2 is configured to perform energy storage integration processing on the signal output by the push-pull circuit 1 and output the corresponding integrated voltage signal to the hysteresis comparator 3.

[0050] The hysteresis comparator 3 is configured to output a corresponding detection signal based on the integrated voltage signal input to the energy storage integrator circuit 2. This detection signal can characterize whether the target under monitoring has any operational abnormalities.

[0051] In this disclosure, the target to be monitored (e.g., a chip, MCU) serves as the trigger source for the entire watchdog circuit. When the target to be monitored is working normally, it will continuously output a square wave signal (with a duty cycle of 50% and a frequency range that can be preset according to actual conditions, ranging from hundreds of hertz to thousands of hertz). When the target to be monitored malfunctions (e.g., the program crashes), it will continuously output a high-level signal or a low-level signal (generally the same level as the output level of the target to be monitored just before the malfunction occurs).

[0052] Figure 2 This is a timing diagram illustrating the integrated voltage signal and detection signal of the target under monitoring during normal operation in an embodiment of this disclosure. Figure 2As shown, when the target under monitoring is working normally, it continuously outputs a square wave signal to the push-pull circuit 1. The push-pull circuit 1 amplifies the signal input from the target and outputs the amplified signal (also a square wave signal) to the energy storage integrator circuit 2. The energy storage integrator circuit 2 performs energy storage integration based on the received square wave signal. When the square wave signal is high, the energy storage integrator circuit 2 charges, and the voltage of the integrated voltage signal output by the energy storage integrator circuit 2 (i.e., the voltage at point G) gradually increases. When the square wave signal is low, the energy storage integrator circuit 2 discharges, and the voltage of the integrated voltage signal output by the energy storage integrator circuit 2 gradually decreases. That is, the integrated voltage signal output by the energy storage integrator circuit 2 is a periodic triangular wave signal. It should be noted that the maximum voltage of the triangular wave signal will be higher than the upper threshold voltage Vth+ of the hysteresis comparator 3, and the minimum voltage of the triangular wave signal will be lower than the lower threshold voltage Vth- of the hysteresis comparator 3. That is, the voltage of the integrated voltage signal output by the energy storage integrator circuit 2 will traverse the hysteresis voltage range [Vth-, Vth+] of the hysteresis comparator 3; specifically, when the integrated voltage signal rises from Vth+ to above Vth+, the hysteresis comparator 3 outputs a high level; when the integrated voltage signal falls from Vth- to below Vth-, the hysteresis comparator 3 outputs a low level. In other words, the detection signal output by the hysteresis comparator 3 (voltage at point OUT) is a periodic square wave signal.

[0053] Figure 3 This is a timing diagram illustrating the integrated voltage signal and the detection signal when the target to be monitored operates abnormally, as shown in an embodiment of this disclosure. Figure 3 As shown, when the target under monitoring malfunctions, if it continuously outputs a high-level signal, the energy storage integrator circuit 2 charges, and the voltage of the integrated voltage signal output by the energy storage integrator circuit 2 gradually increases. When the integrated voltage signal exceeds the upper threshold voltage Vth+ of the hysteresis comparator 3, the hysteresis comparator 3 outputs a high level. Thereafter, the integrated voltage signal maintains the first operating voltage VCC provided by the push-pull circuit 1 (always exceeding the upper threshold voltage Vth+ of the hysteresis comparator 3), and the hysteresis comparator 3 continuously outputs a high level. That is, the detection signal output by the hysteresis comparator 3 is a continuous high-level signal.

[0054] Figure 4 This is another timing diagram of the integrated voltage signal and the detection signal when the target to be monitored is operating abnormally, as described in this disclosure. Figure 4As shown, when the target under monitoring malfunctions, if it continuously outputs a low-level signal, the energy storage integrator circuit 2 discharges, and the voltage of the integrated voltage signal output by the energy storage integrator circuit 2 gradually decreases. When the integrated voltage signal is lower than the lower threshold voltage Vth- of the hysteresis comparator 3, the hysteresis comparator 3 outputs a low level. Thereafter, the voltage of the integrated voltage signal maintains the second operating voltage VGND provided by the push-pull circuit 1 (always lower than the lower threshold voltage Vth- of the hysteresis comparator 3), and the hysteresis comparator 3 continuously outputs a low level. That is, the detection signal output by the hysteresis comparator 3 is a continuous low-level signal.

[0055] Based on the above, it can be seen that when the detection signal output by the hysteresis comparator 3 is a periodic square wave signal, it can indicate that the target under monitoring is working normally; when the detection signal output by the hysteresis comparator 3 is a continuous high-level signal or a continuous low-level signal, it can indicate that the target under monitoring is working abnormally.

[0056] The technical solution disclosed herein can implement a watchdog circuit based on a simple circuit structure, which can greatly simplify the circuit structure and reduce costs.

[0057] Figure 5 This is a schematic diagram of the circuit structure of another watchdog circuit in an embodiment of this disclosure. Figure 5 As shown, in some embodiments, the push-pull circuit 1 includes: a first resistor R1, an N-type transistor Q1, and a P-type transistor Q2. The first terminal of the first resistor R1 is connected to the target to be monitored, and the second terminal of the first resistor R1 is connected to the control terminals of both the N-type transistor Q1 and the P-type transistor Q2. The first terminal of the N-type transistor Q1 is connected to a first voltage supply terminal, and the second terminal of the N-type transistor Q1 is connected to an energy storage integration circuit 2. The first terminal of the P-type transistor Q2 is connected to a second voltage supply terminal, and the second terminal of the P-type transistor Q2 is connected to an energy storage integration circuit 2.

[0058] The first voltage supply terminal provides the first operating voltage VCC, and the second voltage supply terminal provides the second operating voltage VGND.

[0059] When the target to be monitored outputs a high-level signal, N-type transistor Q1 is turned on (P-type transistor Q2 is turned off), and the first working voltage VCC is written to the energy storage integration circuit 2, which then charges. When the target to be monitored outputs a low-level signal, P-type transistor Q2 is turned on (N-type transistor Q1 is turned off), and the second working voltage VGND is written to the energy storage integration circuit 2, which then discharges.

[0060] In some embodiments, the energy storage integration circuit 2 includes: a second resistor R2 and a first capacitor C1; the first end of the second resistor R2 is connected to the push-pull circuit 1, and the second end of the second resistor R2 is connected to the non-inverting input terminal of the hysteresis comparator 3 and the first end of the first capacitor C1; the second end of the first capacitor C1 is connected to the third voltage supply terminal.

[0061] The third voltage supply terminal provides a third operating voltage, such as the ground voltage VGND.

[0062] In some embodiments, the energy storage integrating circuit 2 further includes a freewheeling diode D1; the cathode of the freewheeling diode D1 is connected to the first terminal of the second resistor R2, and the anode of the freewheeling diode D1 is connected to the second terminal of the second resistor R2. In this disclosure, the freewheeling diode D1 is connected in reverse parallel across the second resistor R2 (inductive load) to absorb the reverse induced electromotive force generated by the load during switching, thereby preventing instantaneous high voltage from damaging the switching devices and control circuit, and improving the reliability and safety of the system.

[0063] In some embodiments, the hysteresis comparator 3 includes: a third resistor R3, a fourth resistor R4, a fifth resistor R5, and an operational amplifier U1; wherein, the first end of the third resistor R3 is connected to the non-inverting input terminal of the operational amplifier U1, and the second end of the third resistor R3 is connected to the output terminal of the operational amplifier U1; the first end of the fourth resistor R4 is connected to the first voltage supply terminal, and the second end of the fourth resistor R4 is connected to the inverting input terminal of the operational amplifier U1; the first end of the fifth resistor R5 is connected to the second voltage supply terminal, and the second end of the fifth resistor R5 is connected to the inverting input terminal of the operational amplifier U1; the non-inverting input terminal of the operational amplifier U1 serves as the non-inverting input terminal of the hysteresis comparator 3, and the output terminal of the operational amplifier U1 serves as the output terminal of the hysteresis comparator 3.

[0064] In this disclosure, taking the second operating voltage VGND as 0V as an example, the center threshold voltage Vmid of the hysteresis comparator 3 is:

[0065] Vmid = VCC * R5 / (R4 + R5)

[0066] The total hysteresis voltage range span (also called "total hysteresis width") of hysteresis comparator 3, Vhys:

[0067] Vhys = VDD * R2 / R3

[0068] Where VDD is the power supply voltage of the operational amplifier.

[0069] The upper threshold voltage Vth+ of hysteresis comparator 3:

[0070] Vth += Vmid + Vhys / 2

[0071] The lower threshold voltage Vth- of hysteresis comparator 3:

[0072] Vth - = Vmid - Vhys / 2

[0073] In some embodiments, the watchdog circuit further includes: a light-emitting circuit 4; the light-emitting circuit 4 is configured to emit light when the detection signal output by the hysteresis comparator 3 is high, and not emit light when the detection signal output by the hysteresis comparator 3 is low.

[0074] By setting up the aforementioned light-emitting circuit 4, users can intuitively understand the high and low level states of the detection signal. That is, when the light-emitting circuit emits light, it indicates that the detection signal is at a high level; when the light-emitting circuit does not emit light, it indicates that the detection signal is at a low level.

[0075] Furthermore, when the user observes that the light-emitting circuit alternates between periodic light emission and non-light emission, it indicates that the detection signal is a periodic square wave signal, and the target under monitoring can be detected to be working normally; when the user observes that the light-emitting circuit continuously emits light or continuously does not emit light, the target under monitoring can be detected to be working abnormally.

[0076] In some embodiments, the light-emitting circuit 4 includes: a light-emitting diode D2; the anode of the light-emitting diode D2 is connected to the output terminal of the hysteresis comparator 3, and the cathode of the light-emitting diode D2 is connected to the third voltage supply terminal.

[0077] In some embodiments, the light-emitting circuit 4 further includes a sixth resistor R6, which is connected in series between the cathode of the light-emitting diode D2 and the third voltage supply terminal.

[0078] The disclosed technical solution has the following advantages:

[0079] From a cost perspective, traditional watchdog timers rely heavily on dedicated chips, which are relatively expensive. In contrast, the technical solution of this invention uses distributed components (such as capacitors, resistors, transistors, operational amplifiers, and diodes). These components are common and inexpensive, significantly reducing hardware costs. This makes it particularly suitable for mass-produced or cost-sensitive products, such as consumer electronics, enhancing product competitiveness while maintaining functionality.

[0080] In terms of flexibility, distributed components can adjust their parameters flexibly according to different application scenarios and performance requirements. For example, in industrial environments with strong electromagnetic interference, the stability and anti-interference capability of the circuit can be enhanced by replacing capacitors and resistors with better anti-interference performance and optimizing the parameters of the push-pull circuit and hysteresis comparator. For medical equipment with extremely high requirements for detection sensitivity, the capacitance, resistance value and hysteresis comparator threshold can be precisely adjusted to achieve more accurate detection.

[0081] In terms of reliability, when the target under monitoring is operating normally, the push-pull circuit works with the capacitor to charge and discharge with a regular square wave signal, and the hysteresis comparator outputs a stable periodic signal. Once the target under monitoring malfunctions (e.g., program crashes), the capacitor's charging state changes, and the hysteresis comparator can quickly detect and output an abnormal signal. Compared to a software watchdog, it will not fail if the program crash happens to occur in the reset code segment, thus offering higher reliability.

[0082] For users, when the monitored target malfunctions, the hysteresis comparator output signal can inform them in various intuitive ways, such as lighting up an LED to send an alarm message. This allows users to promptly grasp the chip's status, facilitating quick response and preventing serious consequences such as production accidents and data loss caused by abnormal operation of the monitored target, greatly improving the system's availability and stability.

[0083] Based on the same inventive concept, this disclosure also provides a processing system, which includes a processing chip and a watchdog circuit. The processing chip is the target to be monitored, and the watchdog circuit is the watchdog circuit provided in the previous embodiment.

[0084] Based on the same inventive concept, this disclosure also provides an electronic device, which includes a processing system, the same processing system provided in the preceding embodiments. The electronic device can be an industrial control device, a medical device, or other device with a processing chip.

[0085] Based on the same inventive concept, the present invention also provides an anomaly detection method for a target to be monitored. Figure 6 This is a flowchart illustrating an anomaly detection method for a target to be monitored, provided as an embodiment of this disclosure. Figure 6 As shown, this anomaly detection method is based on the watchdog circuit provided in the previous embodiment, and the anomaly detection method includes:

[0086] Step S1: The push-pull circuit amplifies the signal input from the target to be monitored and outputs the amplified signal to the energy storage integration circuit.

[0087] Step S2: The energy storage integrator performs energy storage integration processing on the signal output by the push-pull circuit and outputs the corresponding integrated voltage signal to the hysteresis comparator.

[0088] Step S3: The hysteresis comparator outputs a corresponding detection signal based on the integrated voltage signal input to the energy storage integrator circuit. The detection signal can characterize whether the target under monitoring has any abnormal operation.

[0089] For a detailed description of each of the above steps, please refer to the corresponding content in the previous embodiments, which will not be repeated here.

[0090] Example embodiments have been disclosed herein, and while specific terminology has been used, it is for illustrative purposes only and should be construed as such, and is not intended to be limiting. In some instances, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in conjunction with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in conjunction with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of the invention as set forth in the appended claims.

Claims

1. A watchdog circuit, characterized in that, include: Push-pull circuit, energy storage integrator circuit, and hysteresis comparator; The push-pull circuit is connected to the target to be monitored and the energy storage integration circuit respectively, and is configured to amplify the signal input from the target to be monitored and output the amplified signal to the energy storage integration circuit. The energy storage integration circuit is connected to the non-inverting input of the hysteresis comparator and is configured to perform energy storage integration processing on the signal output by the push-pull circuit and output a corresponding integrated voltage signal to the hysteresis comparator. The hysteresis comparator is configured to output a corresponding detection signal based on the integrated voltage signal input to the energy storage integrator circuit.

2. The watchdog circuit according to claim 1, characterized in that, The energy storage integration circuit includes: a second resistor and a first capacitor; The first end of the second resistor is connected to the push-pull circuit, and the second end of the second resistor is connected to the non-inverting input of the hysteresis comparator and the first end of the first capacitor. The second terminal of the first capacitor is connected to the third voltage supply terminal.

3. The watchdog circuit according to claim 2, characterized in that, The energy storage integration circuit also includes: a freewheeling diode; The cathode of the freewheeling diode is connected to the first terminal of the second resistor, and the anode of the freewheeling diode is connected to the second terminal of the second resistor.

4. The watchdog circuit according to claim 1, characterized in that, The push-pull circuit includes: a first resistor, an N-type transistor, and a P-type transistor; The first end of the first resistor is connected to the target to be monitored, and the second end of the first resistor is connected to the control electrode of both the N-type transistor and the P-type transistor. The first terminal of the N-type transistor is connected to the first voltage supply terminal, and the second terminal of the N-type transistor is connected to the energy storage integration circuit. The first terminal of the P-type transistor is connected to the second voltage supply terminal, and the second terminal of the P-type transistor is connected to the energy storage integration circuit.

5. The watchdog circuit according to claim 1, characterized in that, The hysteresis comparator includes: a third resistor, a fourth resistor, a fifth resistor, and an operational amplifier; The first end of the third resistor is connected to the non-inverting input terminal of the operational amplifier, and the second end of the third resistor is connected to the output terminal of the operational amplifier. The first end of the fourth resistor is connected to the first voltage supply terminal, and the second end of the fourth resistor is connected to the inverting input terminal of the operational amplifier. The first end of the fifth resistor is connected to the second voltage supply terminal, and the second end of the fifth resistor is connected to the inverting input terminal of the operational amplifier. The non-inverting input of the operational amplifier serves as the non-inverting input of the hysteresis comparator, and the output of the operational amplifier serves as the output of the hysteresis comparator.

6. The watchdog circuit according to any one of claims 1 to 5, characterized in that, Also includes: Light-emitting circuit; The light-emitting circuit is configured to emit light when the detection signal output by the hysteresis comparator is high, and not emit light when the detection signal output by the hysteresis comparator is low.

7. The watchdog circuit according to claim 6, characterized in that, The light-emitting circuit includes: a light-emitting diode; The anode of the light-emitting diode is connected to the output terminal of the hysteresis comparator, and the cathode of the light-emitting diode is connected to the third voltage supply terminal.

8. A processing system, characterized in that, include: The processing chip and the watchdog circuit as described in any one of claims 1 to 7, wherein the target to be monitored is the processing chip.

9. An electronic device, characterized in that, include: The processing system as described in claim 8.

10. An anomaly detection method for a target to be monitored, characterized in that, The anomaly detection method is based on any one of the watchdog circuits described in claims 1 to 7, and the anomaly detection method includes: The push-pull circuit amplifies the signal input from the target to be monitored and outputs the amplified signal to the energy storage integration circuit. The energy storage integration circuit performs energy storage integration processing on the signal output by the push-pull circuit and outputs a corresponding integrated voltage signal to the hysteresis comparator. The hysteresis comparator outputs a corresponding detection signal based on the integrated voltage signal input to the energy storage integrator circuit. The detection signal can characterize whether the target under monitoring has any operational abnormalities.

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