A self-discharge control valve circuit capable of fast power-down detection and long-time data preservation

Abstract

The utility model discloses a kind of self-discharge control valve circuit of quick power failure detection and long-time data storage, the control valve circuit includes backflow prevention and self-discharge control valve circuit unit, power failure long-time power supply circuit unit, power failure quick detection circuit unit, backflow prevention and self-discharge control valve circuit unit is connected by power failure long-time power supply circuit unit with power failure quick detection circuit unit;The backflow prevention and self-discharge control valve circuit unit includes control valve chip, INA pin, INB pin of control valve chip are connected with power failure long-time power supply circuit unit, the VM pin of control valve chip is connected with power supply port, the OA pin of control valve chip is connected with the first pin of the one end of capacitor C7, connector M1 respectively, the other end of capacitor C7, the second pin of connector M1 are all connected with the OB pin of control chip, the GND pin of control valve chip is grounded.

Description

Technical Field

[0001] This utility model relates to the field of household detection alarms, and in particular to a self-discharge control valve circuit that can quickly detect power failure and retain data for a long time. Background Technology

[0002] With social progress and technological development, household combustible gas detectors have become widely used. Household combustible gas detectors, also known as home detectors, are required to record power failures and save related data in the event of a 220V power outage, according to the relevant national standard GB15322.2. The device uses a 220V to 12V voltage conversion circuit to power the internal system. The 220V power supply and power failure process is thus converted into a 12V power supply and power failure process. Based on this, different professionals in the industry have designed different power failure processes. like Figure 1 As shown, it is a conventional valve control circuit, which can only control the robot arm. During the robot arm's operation, the voltage drops slightly. If it is used to control the solenoid valve, the 12V voltage will be pulled very low, below 5V, during the valve's operation. Furthermore, during low voltage detection, the energy stored in capacitor C6 will flow back to the 12V terminal, affecting the voltage detection. like Figure 2 As shown, a resistor R2 is added. Resistor R2 has a current-limiting function. Different resistance values ​​can solve the problem that the robot and the solenoid valve cannot share the same circuit. Adjusting the resistance value of resistor R2 can drive both the robot and the solenoid valve. However, the electrical energy stored in capacitor C6 will still flow back to the 12V terminal, affecting the voltage detection. like Figure 3 As shown, diodes D2 and D4 power two circuits. VBAT is used only for clock power supply to resistor RT and capacitor C. VBAT is a button battery and cannot be used for normal device operation or data storage. The 12V voltage drops to 5V first. At this time, the step-down chip U1 stops working. The 5V terminal supplies power to the subsequent sensor load and control chip. Due to the large power of the sensor load, the 5V discharge process is very fast during the voltage drop from 5V to VBAT. It is not enough to write the power failure record storage data or other data, nor is it enough to maintain the control chip's processing pin control level change. Sensor load U4 is a normal sensor load used for gas detection. It has a large current of about 160mA. After the 12V power failure, the sensor load acts as the main discharge load of the 12V power supply. It is converted to 5V by the step-down chip U1, and then the sensor load discharges. like Figure 4As shown, this is a conventional voltage detection without level transition. When the external 12V power supply is disconnected, the 12V voltage drops slowly. During this process, the CHECK_12V pin level changes slowly. When the pin level is determined to be low, the 12V voltage has dropped to a level that cannot support the normal operation of the device or write to memory.

[0003] In summary, existing solutions all suffer from drawbacks such as long power-off processes and short data retention processes, which may result in power-off records not being saved. In addition, the home alarm involves valve control processes, which include controlling the actions of the robotic arm and solenoid valve. Since the current consumption and the impact on 12V are different in these two processes, the existing circuit design can hardly meet the requirements of these two processes, and it is necessary to improve it. Summary of the Invention

[0004] The purpose of this invention is to address the above-mentioned problems by providing a self-discharge control circuit that improves the speed of power failure detection, the efficiency of writing data during power failure, and the control efficiency, enabling rapid power failure detection and long-term data storage.

[0005] To achieve the above objectives, the technical solution of this utility model is as follows: A self-discharge control circuit with rapid power-down detection and long-term data retention is disclosed. The control circuit includes an anti-backflow and self-discharge control circuit unit, a long-term power-down power supply circuit unit, and a rapid power-down detection circuit unit. The anti-backflow and self-discharge control circuit unit is connected to the long-term power-down power supply circuit unit and the rapid power-down detection circuit unit. The anti-backflow and self-discharge control circuit unit includes a control chip. The INA and INB pins of the control chip are connected to the long-term power-down power supply circuit unit. The VM pin of the control chip is connected to the power supply port. The OA pin of the control chip is connected to one end of capacitor C7 and the first pin of connector M1, respectively. The other end of capacitor C7 and the second pin of connector M1 are both connected to the OB pin of the control chip. The GND pin of the control chip is grounded.

[0006] Furthermore, the VM pin of the valve control chip is connected to the 12VA port, one end of resistor R3, one end of capacitor C6, and one end of resistor R2, respectively. The other end of capacitor C6 and the other end of resistor R3 are grounded. The other end of resistor R2 is connected to the 12VB port, the cathode of diode D1, and one end of resistor R1, respectively. The anode of diode D1 is connected to the 2V port and the base of transistor Q1, respectively. The emitter of transistor Q1 is connected to the other end of resistor R1, and the collector of transistor Q1 is grounded.

[0007] Furthermore, the long-term power-down supply circuit unit includes a step-down chip and a control chip. The CL1 pin of the control chip is connected to the INA pin of the control valve chip, the AIN0 pin of the control chip is connected to the INB pin of the control valve chip, the VDD pin of the control chip is connected to the 5VA port, one end of capacitor C5, one end of capacitor C4, the cathode of diode D2, and the cathode of diode D4, respectively, and the LXT pin of the control chip is connected to the fast power-down detection circuit unit. The other ends of capacitor C4 and capacitor C5 are both grounded; the anode of diode D4 is connected to VBA. The T port is connected to the positive terminal of the battery BAT, and the negative terminal of the battery BAT is grounded; the anode of diode D2 is connected to the cathode of diode D3, the 5VB port, one end of capacitor C3, one end of capacitor C2, and one end of resistor R7, respectively, and the other ends of capacitor C3, capacitor C2, and resistor R7 are all grounded; the anode of diode D3 is connected to the 5V port, the sensor load, and the LX pin of the step-down chip, respectively, and the IN pin of the step-down chip is connected to one end of capacitor C1 and the 12V port, respectively, and the GND pin of the step-down chip and the other end of capacitor C1 are both grounded.

[0008] Furthermore, the power-down fast detection circuit unit includes a transistor Q2. The base of transistor Q2 is connected to one end of resistor R4 and one end of resistor R5, respectively. The other end of resistor R4 is connected to a 12V port. The other end of resistor R5 and the emitter of transistor Q2 are both grounded. The collector of transistor Q2 is connected to one end of resistor R6 and the LXT pin of the control chip, respectively. The other end of resistor R6 is connected to a 5VA port.

[0009] Compared with the prior art, the advantages and positive effects of this utility model are: This invention proposes a self-discharge control valve circuit with rapid power failure detection and long-term data retention. Utilizing fewer discrete components, it achieves rapid power failure detection and provides continuous power to the control chip even during power failure to store power failure records and other data. Furthermore, the control valve section, by adjusting the current-limiting resistor, can be used to control robotic arms and solenoid valves, preventing energy feedback from the control valve section to the power supply. The electrical energy in the control valve section is automatically discharged after a power failure. This circuit has few components, is simple, stable, and reliable, thereby reducing the production cost of products using this circuit and facilitating its market promotion and application. Attached Figure Description

[0010] To more clearly illustrate the technical solutions in the embodiments of this utility model 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 this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 Circuit for conventional valve control Figure 1 ; Figure 2 For conventional valve control circuits Figure 2 ; Figure 3 Circuit diagram for a conventional power supply circuit; Figure 4 This is a circuit diagram for conventional voltage detection. Figure 5 This is an overall circuit structure diagram of the present invention; Figure 6 Circuit diagram of the backflow prevention and self-discharge control valve circuit unit; Figure 7 Circuit diagram of the long-term power supply circuit unit during power outage; Figure 8 Circuit diagram of the power failure rapid detection circuit unit; Figure 9 This is a circuit diagram illustrating the implementation of this utility model. Detailed Implementation

[0012] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, any modifications, equivalent substitutions, improvements, etc., made by those skilled in the art to all other embodiments obtained without creative effort should be included within the protection scope of the present utility model.

[0013] like Figures 5 to 9 As shown, this utility model discloses a self-discharge control valve circuit that enables rapid power-down detection and long-term data retention. The circuit features a fast 12V power-down process and a long system power supply duration after the 12V power-down. The control valve does not affect the voltage of the 12V terminal or the system power supply terminal. Devices using this utility model are safe and reliable. The circuit is simple, stable, reliable, has few components, and is low in cost. This greatly improves the power-down detection speed, power-down data writing efficiency, and control efficiency of devices using this utility model, facilitating the market promotion and utilization of related equipment.

[0014] The overall circuit diagram of the valve control circuit is as follows: Figure 5As shown, it consists of three parts: a backflow prevention and self-discharge control valve circuit, a long-term power-off power supply circuit, and a level-flipping fast power-off detection circuit. The 12V terminal voltage is formed by converting 220V to 12.5V, or directly by an external 12.5V power supply. VBAT is powered by an external button battery and is mainly used for the low-power clock operation of the control chip. 5VA is the voltage terminal that supplies power to the control chip after conversion. 12VA is the power supply terminal for the control valve chip. Signal resistors RA and RB are used to control the valve's movement, including the forward and reverse rotation of the robotic arm and the engagement of the solenoid valve. CHECK_12V is the 12V terminal voltage power-off detection signal, used by the control chip to determine whether there is a power failure. GND is the negative terminal of the device's power supply.

[0015] The working process of this valve control circuit is as follows: When the 12V terminal is powered on, the device system begins operation. The 12V terminal supplies power to the energy storage capacitor C6 through diode D1 and resistor R2. Diode D1 is unidirectional to prevent energy from flowing back from capacitor C6 to the 12V terminal, and resistor R2 limits the charging current to capacitor C6. Connector M1 is used to connect to a robotic arm or solenoid valve; the resistance of R2 differs depending on the type of valve connected to connector M1. Simultaneously, the 12V terminal is converted to 5V by step-down chip U1 to power the sensor load and control chip. The 5V terminal then supplies power to capacitor C3 through diode D3. Power supply: Capacitor C3 stores energy, capacitor C2 filters high-frequency voltage ripple, and diodes D2 and D4 form a two-to-one multiplexer circuit. When 5VB is higher than the VBAT terminal voltage, 5VB supplies power to the control chip, and the system operates normally. At the same time, the 12V terminal forms a detection control voltage CEN through the voltage divider circuit resistors R4 and R5. CEN controls the flip circuit to form the flipped level CHECK_12V. The CHECK_12V signal is sent to the control chip to determine the power-on and power-off processes. The flip circuit consists of resistor R6 and transistor Q2.

[0016] When the 12V terminal loses power, the voltage divider formed by resistors R4 and R5 can quickly detect the power loss. CEN, after toggling, forms a high-level CHECK_12V, which enters the control chip to determine if a power loss has occurred. CHECK_12V is a steep rising level. When a power loss is detected, the control chip shuts down the port, writes the power loss record and other data, and enters low-power mode. When the 12V terminal loses power, the energy stored in capacitor C1 at the 12V terminal is quickly discharged through the step-down chip U1 and sensor load U4. The energy stored in capacitor C3 is cut off by diode D3, preventing backflow to the 5V terminal. The energy stored in capacitor C3 is used to power the control chip after the 12V terminal loses power. When the 5VB terminal loses power... When the voltage at the 5VB terminal is lower than the VBAT terminal voltage, diode D2 is cut off, and the VBAT terminal supplies power to the control chip. The control chip enters a low-power timing mode. Resistor R7 is used to discharge the energy portion where the 5VB terminal voltage is lower than the VBAT terminal voltage, allowing capacitor C3 to be fully discharged, preparing for the next power-on. At the same time, the energy stored in capacitor C6 is cut off by diode D1, preventing it from flowing back to the 12V terminal. As the 12V terminal voltage decreases, it becomes lower than the 12VB terminal voltage, and transistor Q1 turns on. The energy stored in capacitor C6 is consumed through resistor R2, resistor R1, and transistor Q1. When the 12VA terminal voltage is lower than the transistor Q1's turn-on voltage, resistor R3 is used to fully discharge capacitor C6.

[0017] The above processes are nested to form a loop of power-down detection and power-on detection.

[0018] The backflow prevention and self-discharge control valve circuit section, such as Figure 6 As shown, this part consists of diode D1, resistor R2, resistor R1, transistor Q1, capacitor C6, resistor R3, valve control chip U3, and capacitor C7. Diode D1, resistor R2, resistor R1, transistor Q1, capacitor C6, and resistor R3 form an energy storage, backflow prevention, and self-discharge protection circuit. Valve control chip U3, capacitor C7, and connector M1 form a valve connection circuit. Diode D1 and resistor R2 charge capacitor C6 for energy storage, while resistor R2 limits current. Diode D1 and resistor R1... Transistor Q1 forms a self-discharge circuit, which is used for the self-discharge of capacitor C6 when the 12V terminal voltage drops. Among them, D1 is diode SS14, R2 is 200R resistor, R1 is 2R resistor (2R corresponds to the valve control circuit of the robot arm, and 200R corresponds to the valve control circuit of the solenoid valve), Q1 is transistor SS8550, C6 is 1000uF / 25V electrolytic capacitor, R3 is 20K resistor, U3 is integrated chip MX302, and C7 is 0.1uF / 50V ceramic capacitor.

[0019] Its working process is as follows: When the 12V terminal is powered on, the capacitor C6 is charged and stored through diode D1 and resistor R2. The current generated by resistor R3 keeps diode D1 forward-biased and continuously conducting. The energy stored in capacitor C6 is used to maintain the operation of the robotic arm or solenoid valve connected to connector M1, preventing the 12V terminal voltage from being pulled down. When the 12V terminal is powered off, diode D1 blocks the energy from flowing back from capacitor C6 to the 12V terminal. When the 12V terminal voltage is lower than the 12VB terminal voltage, transistor Q1 conducts, and the energy stored in capacitor C6 is discharged through resistor R2, resistor R1, and transistor Q1. When the 12VA terminal voltage is less than the turn-on voltage of transistor Q1, capacitor C6 is completely discharged through resistor R3.

[0020] Long-term power outage power supply circuit section, such as Figure 7 As shown, this part mainly consists of capacitor C2, capacitor C3, diode D3, diode D2, diode D1, resistor R7, and a step-down chip. The remaining parts are used for voltage conversion, sensor load power consumption, and control chip logic control. Diode D3 is used to charge and store energy in capacitor C3 and cut off the backflow of energy from capacitor C3 to the 5V terminal. Diodes D2 and D4 form a two-to-one circuit, with one of the 5VB and VBAT voltages supplying power to the 5VA terminal. Capacitor C2 is used to filter out high-frequency ripple in the 5VB voltage, and resistor R7 is used for the complete discharge of C3 at low voltage. Among them, C2 is a 10uF ceramic capacitor, C3 is a 1000uF / 10V electrolytic capacitor, D3, D2, and D4 are diodes NSR0320MW2T1, and R7 is a 1M (megohm) resistor. The control chip model is CS32L010F8U6, and the step-down chip model is SY81052ABC.

[0021] Its working process is as follows: When the 12V terminal is powered on, the step-down chip U1 converts the 12V voltage to the 5V terminal. When the 5V terminal is powered on, it charges and stores energy through diode D3 to capacitor C3. Capacitor C2 is used to filter out high-frequency ripple in the 5VB terminal voltage. When the 5VB terminal voltage is higher than the VBAT terminal voltage, the 5VB terminal voltage supplies power to the control chip through diode D2. At this time, power-on data and other data can be recorded. The control chip U2 can also control the valve control chip U3 through signal resistor RA and resistor RB. The valve control chip U3 controls the valve action. The sensor load U4 is mainly used to detect other data of the equipment. At the same time, it acts as a load during the 12V terminal power failure, consuming the energy of the 12V terminal.

[0022] After the power-on process is completed, when the 12V terminal loses power, the energy stored in capacitor C1 is consumed by the sensor load U4 through the step-down chip U1. Then, the step-down chip U1 is turned off, the 5V terminal voltage is 0V, and the energy stored in capacitor C3 supplies power to the control chip U2 through diode D2. The control chip U2 closes the relevant ports and saves the power-off record and other data records. When the voltage of the 5VB terminal is lower than that of the VBAT terminal, diode D2 is cut off, diode D4 is turned on, the VBAT terminal supplies power to the 5VA terminal, and the control chip U2 enters the low-power mode.

[0023] The power-down fast detection circuit section with level inversion, such as Figure 8 As shown, the circuit consists of two parts: a voltage divider circuit with resistors R4 and R5, and a level-flipping resistor with resistor R6 and transistor Q2. The voltage divider circuit with resistors R4 and R5 detects the power-on and power-off process of the 12V terminal. The level-flipping circuit with resistor R6 and transistor Q2 transforms the slow rise or fall of CEN into a steep rise or fall, thus completing the rapid detection process of power-on and power-off voltage. Among them, R4 is a 10K resistor, R5 is a 1K resistor, R6 is a 10K resistor, and Q2 is a transistor SS9013. Resistors R4 and R5 divide the voltage to detect the power-on and power-off process of the 12V terminal. At the same time, when the 12V terminal voltage is very low, resistors R4 and R5 absorb the energy in capacitor C1, causing capacitor C1 to discharge completely. The power-off process of the 12V terminal voltage is slow, causing the CEN signal to change slowly. A level-flipping circuit composed of resistor R6 and transistor Q2 transforms the slow rise or fall of CEN into a steep rise or fall process, thereby completing the rapid detection process of power-on and power-off voltage.

[0024] Based on the above description and relevant circuit knowledge, the values ​​of the resistors and capacitors can be calculated. Figure 9 A specific application circuit of this utility model is given, and the value of each component is given, but all components are not limited to this value.

[0025] like Figure 9 As shown, in actual operation: the actual power supply for 12V is 12.5V, for 12VB it is 12.4V, and for 12VA it is 12.4V. When the equipment is working normally, the voltages for 12V / 12VB / 12VA can all be considered as 12V. The same applies to the following, so I will not repeat it. This does not affect the valve operation. The 12V is formed by converting 220V to 12.5V, or directly by external 12.5V power supply. Diodes D1 / D2 / 3 / D4 are germanium diodes with a voltage of less than 0.3V.

[0026] Its working principle is as follows: Under normal operating conditions, the 12V terminal provides normal power, forming a 12VB voltage through diode D1. Simultaneously, the electrolytic capacitor C6 is charged through diode D1 and resistor R2, storing energy in capacitor C6. When connector M1 is connected to an external robotic arm, resistor R2 = 2 ohms; when connector M1 is connected to an external solenoid valve, resistor R2 = 200 ohms. After capacitor C6 has stored energy, the energy in C6 cannot be returned to the 12V terminal as current. Resistor R3 forms a constant current of 0.62mA, keeping diode D1 continuously conducting. Furthermore, when the 12V power is off, a small current can continuously discharge the energy in capacitor C6. When the robotic arm is in operation, the robotic arm current is approximately 90mA, with a discharge time of 11 seconds, mainly through the 12V / diode... The robot arm is powered by diode D1, resistor R2, capacitor C6, and M1. Capacitor C6 stabilizes the voltage and prevents voltage spikes. Resistor R2 = 2Ω. When an external solenoid valve is connected to M1, the solenoid valve current is <1.5A and the discharge time is <1S, generally within 200ms. The solenoid valve is mainly powered by 12V / diode D1 / resistor R2 / capacitor C6 / M1. Capacitor C6 stabilizes the voltage and provides transient energy without affecting the 12V terminal voltage. In this case, resistor R2 = 2Ω prevents the large current at startup from pulling down the 12V voltage. 12.4V / 20Ω = 62mA, limiting the charging current from 12V to 12VA to within 62mA to prevent the 12V from being pulled down.

[0027] When power is lost, the 12V voltage drops slowly first, and the sensor load consumes the 12V voltage. The maximum power loss time is 20ms. At this time, the 12V is lower than 12VB, the transistor Q1 conducts, and the energy on the capacitor C6 is discharged through resistor R2 / resistor R1 / transistor Q1. The discharge time is 2s. Without this self-discharge network of resistor R2 / resistor R1 / transistor Q1, the discharge time can reach more than 20s. The discharge time is too long. The function of diode D1 is to prevent the energy of capacitor C6 from flowing back to the 12V terminal when the 12V is lost, which can accelerate the power loss process of the 12V terminal.

[0028] The voltage detection incorporates a level switching mechanism, which consists of resistor R6 and transistor Q2. When the 12V terminal is powered, resistors R4 and R5 divide the voltage and conduct transistor Q2, causing the input pin signal CHECK_12V of the control chip to be low. When the 12V power is lost, the voltage divider from resistors R4 and R5 turns off transistor Q2 within <1ms, causing the input pin of the control chip to be at a 5VA high level, thus achieving rapid detection of the power loss process.

[0029] Capacitor C2, capacitor C3, diode D3, diode D2, and diode D4 form a long-term power supply circuit, facilitating the control chip's power-down recording and data preservation. Capacitors C2 and C3 are used for filtering and energy storage. When the 12V power fails, the 5V terminal is de-energized. Diode D3 prevents the energy stored in capacitors C2 and C3 from flowing back to the 5V terminal. Resistor R7 ensures complete self-discharge of capacitors C2 and C3 when 5VB < VBAT. The process of 5VB dropping to VBAT takes more than 2 seconds, even exceeding 10 seconds. This time is related to the control chip's control logic. 2 seconds is sufficient to ensure complete preservation of power-down records and data before entering low-power mode. When VBAT supplies power to the control chip, the control chip enters sleep mode. In sleep mode, the control chip's power consumption is less than 24uA, which is extremely low.

[0030] This utility model consists of three parts: an anti-backflow and self-discharge control valve circuit, a long-term power-down power supply circuit, and a level-flipping fast power-down detection circuit. When the 12V terminal loses power, the voltage divider formed by resistors R4 and R5 can detect the power loss process. The slowly changing signal CEN is flipped to form a rapidly changing level signal CHECK_12V, which enters the control chip. The control chip determines whether a power loss has occurred. When CHECK_12V is a steep rising level, it is determined that a power loss has occurred. Then, the control chip closes the port, writes the power loss record and other data, and then enters a low-power mode. When the 12V terminal loses power, the energy stored in capacitor C1 at the 12V terminal is quickly discharged through the step-down chip U1 and the sensor load U4. The stored energy is cut off by diode D3, preventing it from flowing back to the 5V terminal. The energy stored in capacitor C3 is used to power the control chip after power failure. When the voltage at the 5VB terminal is lower than the voltage at the VBAT terminal, diode D2 is cut off, and the VBAT terminal voltage powers the control chip, causing the control chip to enter a low-power timing mode. Simultaneously, the energy stored in capacitor C6 is cut off by diode D1, preventing it from flowing back to the 12V terminal. As the 12V terminal voltage decreases, it falls below the 12VB terminal voltage, causing transistor Q1 to conduct. The energy stored in capacitor C6 is then released through resistor R2, resistor R1, and transistor Q1. This invention features a simple and stable circuit with few components, which helps to improve the market competitiveness of home newspaper products using this technology.

Claims

1. A self-discharge control circuit that rapidly detects power failure and retains data for a long time, characterized in that: The valve control circuit includes a backflow prevention and self-discharge control circuit unit, a long-term power-off power supply circuit unit, and a fast power-off detection circuit unit. The backflow prevention and self-discharge control circuit unit is connected to the fast power-off detection circuit unit through the long-term power-off power supply circuit unit. The backflow prevention and self-discharge control circuit unit includes a valve control chip. The INA and INB pins of the valve control chip are connected to the long-term power-off power supply circuit unit. The VM pin of the valve control chip is connected to the power supply port. The OA pin of the valve control chip is connected to one end of capacitor C7 and the first pin of connector M1, respectively. The other end of capacitor C7 and the second pin of connector M1 are both connected to the OB pin of the control chip. The GND pin of the valve control chip is grounded.

2. The self-discharge control valve circuit with rapid power failure detection and long-term data retention as described in claim 1, characterized in that: The VM pin of the valve control chip is connected to the 12VA port, one end of resistor R3, one end of capacitor C6, and one end of resistor R2, respectively. The other end of capacitor C6 and the other end of resistor R3 are grounded. The other end of resistor R2 is connected to the 12VB port, the cathode of diode D1, and one end of resistor R1, respectively. The anode of diode D1 is connected to the 2V port and the base of transistor Q1, respectively. The emitter of transistor Q1 is connected to the other end of resistor R1, and the collector of transistor Q1 is grounded.

3. The self-discharge control circuit with rapid power failure detection and long-term data retention as described in claim 2, characterized in that: The long-term power-off supply circuit unit includes a step-down chip and a control chip. The CL1 pin of the control chip is connected to the INA pin of the valve control chip, and the AIN0 pin of the control chip is connected to the INB pin of the valve control chip. The VDD pin of the control chip is connected to the 5VA port, one end of capacitor C5, one end of capacitor C4, the cathode of diode D2, and the cathode of diode D4, respectively. The LXT pin of the control chip is connected to the fast power-off detection circuit unit. The other ends of capacitors C4 and C5 are both grounded. The anode of diode D4 is connected to the VBAT port. Connect the positive terminal of battery BAT to the ground; connect the negative terminal of battery BAT to the ground; connect the anode of diode D2 to the cathode of diode D3, the 5VB port, one end of capacitor C3, one end of capacitor C2, and one end of resistor R7; connect the other ends of capacitor C3, capacitor C2, and resistor R7 to the ground; connect the anode of diode D3 to the 5V port, the sensor load, and the LX pin of the step-down chip; connect the IN pin of the step-down chip to one end of capacitor C1 and the 12V port; connect the GND pin of the step-down chip and the other end of capacitor C1 to the ground.

4. The self-discharge control valve circuit with rapid power failure detection and long-term data retention as described in claim 3, characterized in that: The power-down fast detection circuit unit includes a transistor Q2. The base of transistor Q2 is connected to one end of resistor R4 and one end of resistor R5, respectively. The other end of resistor R4 is connected to the 12V port. The other end of resistor R5 and the emitter of transistor Q2 are both grounded. The collector of transistor Q2 is connected to one end of resistor R6 and the LXT pin of the control chip, respectively. The other end of resistor R6 is connected to the 5VA port.

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