An airborne computer secondary power supply monitoring method and system

Abstract

A monitoring method and system for the secondary power supply of an airborne computer according to the present invention belong to the technical field of power supply monitoring for aviation airborne electronic devices. The method uses main devices such as a voltage stabilizing diode, a comparator, a retriggerable monostable flip-flop, etc., to realize functions such as power supply monitoring and power-on reset of the airborne computer. That is, it can realize secondary power supply fault detection, and also meet the power-on reset and power-off reset functions. When a secondary power supply fault occurs, the automatic reset of the processor can be realized, avoiding the processor from collecting and processing incorrect data information and then causing incorrect output control in the case of a secondary power supply fault. Its design is simple, easy to implement, has strong anti-interference ability, can effectively detect secondary and tertiary power supply faults, and can realize power-on and power-off reset functions. It is especially suitable for the airborne electronic environment.

Description

Technical Field

[0001] The present invention relates to the field of power supply monitoring for airborne electronic equipment, and particularly to a method and system for monitoring the secondary power supply of an airborne computer. Background Art

[0002] During the design process of an airborne embedded computer, it is necessary to monitor the secondary power supply output by the embedded system power supply. The main function of power supply monitoring is to output a power supply invalid signal when the secondary power supply loses power, and output a power supply valid signal when the secondary power supply resumes. This enables the computer to timely understand the working condition of the power supply, and can determine the effectiveness of the computer, improving the system detection rate and testability.

[0003] The first method is relatively common. Many designers use an analog-to-digital converter (A / D chip) to collect secondary power supply signals, and even primary power supply signals, and determine the correctness of the power supply signals through software. However, this method has serious logical problems. For example, when the processor power supply fails, all faults detected by the processor at this time are not credible. Another example is when the A / D conversion chip fails, all fault detections collected through A / D are not credible. Therefore, this method has serious logical problems, and this conclusion can be obtained through simple fault tree analysis.

[0004] The second method, as described in the patent "A Power Supply Monitoring Circuit", has the greatest advantage of monitoring the +5V voltage through the +15V voltage and outputting a discrete signal to identify the correctness of the signal, avoiding the serious logical problems of the first method. However, the new problem introduced is that due to the development of computer technology, mainly the development of core processor technology, the secondary power supply inside the airborne computer has increased, and in key safety areas such as control, the failure of the secondary power supply leads to the failure of the safety state control of the entire product, bringing very serious problems. Therefore, it is necessary to comprehensively monitor the secondary power supply inside the entire airborne computer to achieve the safety state control of airborne electronic products under secondary power supply failure and avoid secondary disasters. Summary of the Invention

[0005] In view of this, the embodiments of the present disclosure provide a method for monitoring the secondary power supply of an airborne computer, which can effectively detect secondary power supply faults, can be used as an input for the power supply fault of the safety state control, and can also be used as the core reset function of the whole machine.

[0006] A method for monitoring the secondary power supply of an airborne computer, where multiple power supplies are installed on the aircraft. The power supplies are configured with a first AND logic circuit, a second AND logic circuit, a third AND logic circuit, a manual reset circuit, a monostable flip-flop, and a watchdog trigger reset conditioning circuit. The monostable flip-flop is used to output a power supply intact indication signal, and the power supply monitoring and watchdog trigger reset conditioning circuit are triggered through the monostable flip-flop. The method includes:

[0007] Each of the power supplies is configured with a monitoring circuit and is set with different voltage thresholds. When the working voltage detected by the monitoring circuit corresponding to each power supply is greater than the corresponding threshold voltage, a feedback is made; the output end of the monitoring circuit of each power supply is connected to the input end of the first AND logic circuit; the output end of the first AND logic circuit is connected to the input end of the monostable flip-flop;

[0008] The output end of the monostable flip-flop and the output end of the manual reset circuit are both used as the input ends of the second AND logic circuit. The manual reset circuit is used to output a low level of the manual reset signal HW_RESET when the manual reset switch is "ground"; when the manual reset switch is "on", the manual reset signal HW_RESET outputs a high level;

[0009] The output ends of the second AND logic circuit and the watchdog trigger reset conditioning circuit are used as the input ends of the third AND logic circuit, and the third AND logic circuit outputs. Among them: for each power supply monitoring and watchdog trigger reset conditioning circuit, the result of performing an "AND" operation on all power supply monitoring outputs P_Monitor and the manual reset signal HW_RESET is used as the input of the monostable flip-flop. When either the power supply monitoring output or the manual reset signal is low, the monostable flip-flop outputs a low level, otherwise it outputs a PWM wave with a determined duty cycle; the output of the stable flip-flop can be used as a signal output indicating whether each power supply is normally powered, and after performing an "AND" operation with the watchdog bark pulse, it is used as the reset signal of the airborne computer.

[0010] Compared with the prior art, the beneficial effects that can be achieved by at least one of the above technical solutions adopted in the embodiments of this specification at least include: The method of the present invention uses main devices such as a voltage regulator diode, a comparator, a retriggerable monostable flip-flop, etc. to realize functions such as power supply monitoring and power-on reset of the airborne computer. That is, it can realize secondary and tertiary power supply fault detection, and also meet the power-on reset and power-off reset functions. When secondary and tertiary power supply faults occur, the automatic reset of the processor can be realized, avoiding the processor from collecting and processing incorrect data information and then causing incorrect output control in the case of secondary and tertiary power supply faults. The design of the present invention is simple, easy to implement, and has strong anti-interference ability. It can effectively detect secondary and tertiary power supply faults and can realize power-on and power-off reset functions. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0012] Figure 1It is the schematic diagram of +15V power supply monitoring provided by the embodiment of the present invention;

[0013] Figure 2 It is the schematic diagram of -15V power supply monitoring provided by the embodiment of the present invention;

[0014] Figure 3 It is the schematic diagram of +5V and three - time power supply monitoring provided by the embodiment of the present invention;

[0015] Figure 4 It is the schematic diagram of ground / open manual reset provided by the embodiment of the present invention;

[0016] Figure 5 It is the secondary power supply monitoring and application architecture diagram provided by the embodiment of the present invention;

[0017] Figure 6 It is the structure diagram of an airborne computer secondary power supply monitoring system.

[0018] Reference numerals in the figure: 600, system; 601, first system module; 602, second system module; 603, third system module. Detailed implementation manners

[0019] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0020] The following illustrates the implementation manners of the present application through specific specific examples. Those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The present application can also be implemented or applied through other different specific implementation manners. The details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts belong to the scope protected by the present application.

[0021] The airborne computer secondary power supply monitoring method provided by the present invention is characterized in that multiple power supplies are installed on the aircraft, and the power supplies are configured as follows. Figure 5 As described, a first AND logic circuit, a second AND logic circuit, and a third AND logic circuit are sequentially arranged from left to right, and a manual reset circuit, a monostable flip - flop, and a watchdog trigger reset conditioning circuit are correspondingly configured. The monostable flip - flop is used to output a power supply intact indication signal, and the power supply monitoring and watchdog trigger reset conditioning circuit are triggered through the monostable flip - flop. The method includes:

[0022] Each power supply is configured with a monitoring circuit and different voltage thresholds are set. When the working voltage detected by the monitoring circuit corresponding to each power supply is greater than the corresponding threshold voltage, feedback is performed; the output end of the monitoring circuit of each power supply is connected to the input end of the first AND logic circuit; the output end of the first AND logic circuit is connected to the input end of the monostable flip-flop;

[0023] The output end of the monostable flip-flop and the output end of the manual reset circuit are both used as the input ends of the second AND logic circuit. The manual reset circuit is used to output a low level of the manual reset signal HW_RESET when the manual reset switch is "ground"; when the manual reset switch is "on", the manual reset signal HW_RESET outputs a high level;

[0024] The output ends of the second AND logic circuit and the watchdog trigger reset conditioning circuit are used as the input ends of the third AND logic circuit, and the third AND logic circuit outputs. Among them: each power supply monitoring and watchdog trigger reset conditioning circuit uses the result of the "AND" operation of all power supply monitoring outputs P_Monitor and the manual reset signal HW_RESET as the input of the monostable flip-flop. When either the power supply monitoring output or the manual reset signal is low, the monostable flip-flop outputs a low level, otherwise it outputs a PWM wave with a determined duty cycle; the output of the stable flip-flop can be used as a signal output indicating whether each power supply is normally powered, and after "AND" with the watchdog bark pulse, it is used as the reset signal of the airborne computer. The second AND logic circuit is configured with a watchdog circuit.

[0025] The multiple power supplies mentioned above, for example, the power supplies include +15V power supply, -15V power supply and +5V and triple power supplies. Among them, the output method of each monitoring circuit includes:

[0026] Such as Figure 1 As shown, the +15V power supply monitoring circuit monitors the +15V power supply voltage in the airborne computer. When it is greater than the set voltage threshold, P_Monitor outputs a high level, otherwise P_Monitor outputs a low level; specifically, the monitoring circuit corresponding to the +15V power supply is composed of a triode, a zener diode, and resistors and capacitors to realize the judgment of whether the +15V power supply is undervoltage. The judgment voltage threshold can be determined by configuring the resistance parameters and the result is output in the form of high / low level;

[0027] Such as Figure 2As shown, the -15V power supply monitoring circuit monitors the -15V power supply voltage in the airborne computer. When the voltage is less than the set voltage threshold, P_Monitor outputs a high level; otherwise, P_Monitor outputs a low level. Specifically, the monitoring circuit corresponding to the -15V power supply consists of two triodes, a zener diode, and resistors and capacitors, which realizes the judgment of whether the -15V power supply is undervoltage. The voltage threshold for judgment can be determined by configuring the resistor parameters and the result is output in the form of high / low level.

[0028] As Figure 3 shown, the +5V and triple power supply monitoring circuit monitors the +5V power supply and various triple power supply voltages in the airborne computer respectively. When the monitored power supply exceeds the set voltage threshold, P_Monitor outputs a low level; otherwise, P_Monitor outputs a high level. Specifically, the monitoring circuit corresponding to the +5V and triple power supplies consists of a comparator, a zener diode, and resistors and capacitors, which realizes the judgment of whether any voltage in the +5V and triple power supplies is undervoltage or overvoltage. The reference drive voltage in this circuit can be selected as the parallel connection of the processor interface voltages in the +5V and triple power supplies, which can ensure that the circuit can still work normally when any power supply fails (otherwise, it cannot be proved whether it is the power supply failure or the circuit itself failure).

[0029] As a specific implementation provided in this case, the manual reset circuit consists of a comparator, a diode, and resistors and capacitors. The manual reset signal is given by the ground / open switch. When the manual reset switch is "ground", the voltage at the negative terminal of the operational amplifier is 0V at this time. According to the voltage division principle, the comparator outputs a low voltage; when the manual reset switch is "open", the voltage at the negative terminal of the comparator is 3.3V after voltage division, and the comparator outputs a high voltage. The specific output voltage value can be determined by configuring the resistor.

[0030] As a specific implementation provided in this case, the power supply monitoring and watchdog trigger reset conditioning circuit realizes its function through a monostable flip-flop. The signal after performing an "AND" operation on the power supply monitoring signals in claims 2-5 and the manual reset signal is used as the input. When the input signal is high (i.e., the power supply monitoring is normal and there is no external manual reset input), the monostable flip-flop is in the stable state and the output is high; when the input signal is low (i.e., there is any undervoltage in the power supply monitoring or there is an external manual reset input), the monostable flip-flop is in the quasi-stable state and outputs a negative pulse. After passing through a level follower by a comparator, it can be used as an indication of the good power supply and output to the processor, and together with the watchdog indication, it passes through a comparator to perform an "AND" operation on the signals. When both the power supply good indication and the watchdog indication are high, the reset signal to the processor is high (the processor is not reset at this time); when either the power supply good indication or the watchdog indication is a negative pulse, the reset signal to the processor is also a negative pulse (which can reset the processor).

[0031] Further, according to the working steps in the use of the above method, including:

[0032] Step 1: Determine the threshold value of the undervoltage of the ±15V power supply voltage according to the requirements, and calculate the resistance value of the configured resistor;

[0033] Step 2: Respectively use the +5V in the airborne computer and each of the three power supply voltages as the input of Claim 4, and select two voltages as the driving voltage of the monitoring circuit to prevent the circuit from malfunctioning after one power supply fails;

[0034] Step 3: The manual reset signal is given by the ground / open switch. When a suitable resistor is configured so that the output is high, the high-level voltage meets the requirements;

[0035] Step 4: Perform an "AND" operation on the results output by the circuits in Steps 1, 2, and 3 and use it as the input of the monostable flip-flop. Select appropriate resistor and capacitor values so that the negative pulse width of the output meets the requirements.

[0036] Embodiment 1

[0037] Please refer to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 at the same time, where Figure 1 is the schematic diagram of the +15V power supply monitoring, Figure 2 is the schematic diagram of the -15V power supply monitoring, Figure 3 is the schematic diagram of the +5V and the three-power supply monitoring, Figure 4 is the schematic diagram of the ground / open manual reset, Figure 5 is the schematic diagram of the power supply monitoring and the watchdog trigger reset, Figure 6 is the secondary power supply monitoring and application architecture diagram.

[0038] Combined with Figure 1 、 Figure 2 、 Figure 3 and Figure 4 , where Figure 1 is the schematic diagram of the +15V power supply monitoring. The main principle is to monitor the +15V power supply voltage in the airborne computer. The key parameters are R1 and R2 in this patent Figure 1 . The combination of R1 = 10Kohm (ohm) and R2 = 3Kohm makes the threshold value of the voltage monitoring 13.5V (10% error), that is, when the +15V power supply voltage is lower than 13.5V, it is indicated as undervoltage at this time, and P_Monitor outputs a low level.

[0039] Where Figure 2It is the schematic diagram of -15V power supply monitoring. The main principle is to monitor the -15V power supply voltage in the airborne computer. Its key parameters are the R1 and R2 in this patent Figure 2 in which the combination of R1 = 10Kohm and R2 = 3Kohm makes the threshold of voltage monitoring -13.5V (with an error of 10%). That is, when the -15V power supply voltage is greater than -13.5V, it indicates undervoltage at this time, and P_Monitor outputs a low level.

[0040] Figure 3 It is the schematic diagram of +5V and tertiary power supply monitoring. The main principle is to monitor the +5V power supply and various tertiary power supply voltages in the airborne computer. Taking the monitoring of 3.3V power supply voltage as an example, select R1 = 2Kohm, R2 = 2Kohm, R3 = 1Kohm, R4 = 3Kohm, divide the 3.3V voltage to 0.5 times and 0.75 times. The configuration resistors of the comparator are selected as R5 = 10Kohm, R2 = 10Kohm, R7 = 100Kohm, R8 = 100Kohm. The regulated voltage value of the zener diode is selected as 2.4V, and the drive voltage is selected as the parallel connection of 5V and 3.3V. Then when the monitored 3.3V power supply voltage is between 2.8V and 4.0V, P_Monitor outputs a high level; when the monitored 3.3V power supply voltage is less than 2.8V or greater than 4.0V, P_Monitor outputs a low level.

[0041] Figure 4 It is the schematic diagram of ground / open manual reset. Its specific working principle is as follows: The manual reset signal comes from an external ground / open type manual switch. By toggling the switch to input the ground or open signal, the output end of the operational amplifier becomes the ground or high level.

[0042] Figure 5 It is the architecture diagram of secondary power supply monitoring and application. Its specific working principle is as follows: The power supply monitoring result and the manual reset result are "AND" operated. At this time, the input voltage is 0V or 3.3V. Using a monostable flip-flop to capture the changes of the power supply monitoring result and the manual reset result, that is, when both are always high, the monostable flip-flop outputs high; when either of them becomes negative or there is a negative pulse, the monostable flip-flop outputs a negative pulse signal with a fixed high state width. After "AND" with the watchdog barking negative pulse through a diode and then through a comparator, it enters the processor. After the processor captures the negative pulse and the duration meets the reset requirements, it performs a power-on reset operation.

[0043] Based on the same inventive concept, an airborne computer secondary power supply monitoring system is also provided in an embodiment of the present invention, as described in the following embodiments. Since the principle of solving problems by an airborne computer secondary power supply monitoring system is similar to that of an airborne computer secondary power supply monitoring method, the implementation of an airborne computer secondary power supply monitoring system can refer to the implementation of an airborne computer secondary power supply monitoring method, and the repeated parts will not be described again. As used hereinafter, the term "unit" or "module" may be a combination of software and / or hardware that can implement a predetermined function. Although the systems described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware is also possible and contemplated.

[0044] As Figure 6 shown, it is a schematic diagram of an airborne computer secondary power supply monitoring system 600 according to an embodiment of the present invention, including:

[0045] The first system module 601 is configured such that each of the power supplies is equipped with a monitoring circuit and different voltage thresholds are set. When the operating voltage detected by the monitoring circuit corresponding to each power supply is greater than the corresponding threshold voltage, a feedback is made; the output end of the monitoring circuit of each power supply is connected to the input end of the first AND logic circuit; the output end of the first AND logic circuit is connected to the input end of the monostable flip-flop;

[0046] The second system module 602 is configured such that the output end of the monostable flip-flop and the output end of the manual reset circuit are both used as the input ends of the second AND logic circuit. The manual reset circuit is configured such that when the manual reset switch is "ground", the manual reset signal HW_RESET outputs a low level; when the manual reset switch is "on", the manual reset signal HW_RESET outputs a high level;

[0047] The third system module 603 is configured such that the output ends of the second AND logic circuit and the watchdog trigger reset conditioning circuit are used as the input ends of the third AND logic circuit, and the third AND logic circuit outputs. Among them: for each power supply monitoring and watchdog trigger reset conditioning circuit, the result of performing an "AND" operation on all power supply monitoring outputs P_Monitor and the manual reset signal HW_RESET is used as the input of the monostable flip-flop. When any one of the power supply monitoring output and the manual reset signal is low, the monostable flip-flop outputs a low level, otherwise it outputs a PWM wave with a determined duty cycle; the output of the stable flip-flop can be used as a signal output indicating whether each power supply is normally powered, and after performing an "AND" operation with the watchdog bark pulse, it is used as the reset signal of the airborne computer.

[0048] The embodiments of the present invention achieve the following technical effects:

[0049] The present invention provides a method for monitoring the secondary and tertiary power supplies of an airborne computer. This method uses main devices such as zener diodes, comparators, and retriggerable monostable flip-flops to achieve functions such as power supply monitoring and power-on reset of the airborne computer. That is, it can achieve secondary and tertiary power supply fault detection, and also meet the power-on reset and power-off reset functions. When secondary and tertiary power supply faults occur, automatic reset of the processor can be realized, avoiding the processor from collecting and processing incorrect data information and then causing incorrect output control in the case of secondary and tertiary power supply faults. The design of the present invention is simple, easy to implement, and has strong anti-interference ability. It can effectively detect secondary and tertiary power supply faults and can also achieve power-on and power-off reset functions.

[0050] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, various changes and modifications can be made to the embodiments of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for monitoring the secondary power supply of an airborne computer. There are multiple power supplies installed on the aircraft, and it is characterized in that, The power supply configuration includes a first AND logic circuit, a second AND logic circuit, a third AND logic circuit, a manual reset circuit, a monostable flip-flop, and a watchdog trigger reset conditioning circuit. The monostable flip-flop is used to output a power supply integrity indication signal. The power supply monitoring and watchdog trigger reset conditioning circuit is triggered through the monostable flip-flop. The method includes: Each of the power supplies is configured with a monitoring circuit and set with different voltage thresholds. When the monitoring circuit corresponding to each power supply detects that the operating voltage is greater than the corresponding threshold voltage, it gives a feedback. The output end of the monitoring circuit of each power supply is connected to the input end of the first AND logic circuit. The output end of the first AND logic circuit is connected to the input end of the monostable flip-flop. The output end of the monostable flip-flop and the output end of the manual reset circuit are both used as the input ends of the second AND logic circuit. The manual reset circuit is used to output a low level of the manual reset signal HW_RESET when the manual reset switch is "ground", and output a high level of the manual reset signal HW_RESET when the manual reset switch is "on". The output ends of the second AND logic circuit and the watchdog trigger reset conditioning circuit are used as the input ends of the third AND logic circuit. The third AND logic circuit outputs. Among them: for each power supply monitoring and watchdog trigger reset conditioning circuit, the result of performing an "AND" operation on all power supply monitoring outputs P_Monitor and the manual reset signal HW_RESET is used as the input of the monostable flip-flop. When either the power supply monitoring output or the manual reset signal is low, the monostable flip-flop outputs a low level, otherwise it outputs a PWM wave with a determined duty cycle. The output of the stable flip-flop is used as the signal output indicating whether each power supply is normally powered, and after performing an "AND" operation with the watchdog bark pulse, it is used as the reset signal of the airborne computer.

2. The method according to claim 1, wherein The power supplies include a +15V power supply, a -15V power supply, and a +5V and triple power supply. Among them, the output method of each monitoring circuit includes: The +15V power supply monitoring circuit monitors the +15V power supply voltage in the airborne computer. When it is greater than the set voltage threshold, P_Monitor outputs a high level, otherwise P_Monitor outputs a low level. The -15V power supply monitoring circuit monitors the -15V power supply voltage in the airborne computer. When it is less than the set voltage threshold, P_Monitor outputs a high level, otherwise P_Monitor outputs a low level. The +5V and triple power supply monitoring circuit monitors the +5V power supply and various triple power supply voltages in the airborne computer respectively. When the monitored power supply exceeds the set voltage threshold, P_Monitor outputs a low level, otherwise P_Monitor outputs a high level.

3. The method according to claim 2, wherein The monitoring circuit corresponding to the +15V power supply consists of a triode, a zener diode, and resistors and capacitors, and realizes the judgment of whether the +15V power supply is undervoltage. The judgment voltage threshold is determined by configuring the resistor parameters and the result is output in the form of high / low level.

4. The method according to claim 2, characterized in that, The monitoring circuit corresponding to the -15V power supply consists of two triodes, a zener diode, and resistors and capacitors, which realizes the judgment of whether the -15V power supply is undervoltage. The voltage threshold for judgment is determined by configuring the resistance parameters, and the result is output in the form of high / low level.

5. The method according to claim 2, characterized in that, The monitoring circuit corresponding to the +5V and triple power supplies consists of a comparator, a zener diode, and resistors and capacitors, which realizes the judgment of whether any of the voltages of the +5V and triple power supplies is undervoltage or overvoltage. The reference drive voltage in this circuit is selected as the parallel connection of the processor interface voltages of the +5V and triple power supplies, ensuring that the circuit still works normally when any power supply fails.

6. The method according to claim 1, characterized in that, The manual reset circuit consists of a comparator, a diode, and resistors and capacitors. The manual reset signal is given by the ground / open switch configured on the aircraft. When the manual reset switch is "ground", the voltage at the negative terminal of the operational amplifier is 0V at this time. According to the voltage division principle, the comparator outputs a low voltage; when the manual reset switch is "open", the voltage at the negative terminal of the comparator is 3.3V after voltage division, and the comparator outputs a high voltage. The specific value of the output voltage is determined by configuring the resistance.

7. The method according to claim 1, characterized in that, The power supply monitoring and watchdog trigger reset conditioning circuit realizes its function through a monostable flip-flop. The signal after the "AND" operation of the output of the power supply monitoring and the manual reset signal is used as the input, where: When the input signal is high, the monostable flip-flop is in the stable state and the output is high; when the input signal is low, the monostable flip-flop is in the quasi-stable state and outputs a negative pulse; after the level is followed through a comparator, it is output to the processor as an indication that the power supply is intact and undergoes an "AND" operation of the signal together with the watchdog indication through a comparator; When both the power supply intact indication and the watchdog indication are high, the reset signal to the processor is high; when either the power supply intact indication or the watchdog indication is a negative pulse, the reset signal to the processor is also a negative pulse.

8. The method according to any one of claims 1 to 7, the working steps include: Step 1: Determine the undervoltage threshold of the ±15V power supply voltage according to the requirements, and calculate the resistance value of the configured resistor; Step 2: Take each of the +5V and triple power supply voltages in the airborne computer as the input of claim 4 respectively, and select two voltages as the drive voltages of the monitoring circuit to prevent the circuit from malfunctioning after one power supply fails; Step 3: The manual reset signal is given by the ground / open switch, and appropriate resistors are configured so that when the output is high, the high-level voltage meets the requirements; Step 4: Perform an "AND" operation on the results output by the circuits in steps 1, 2, and 3 and use it as the input of the monostable flip-flop, and select appropriate resistor and capacitor values so that the width of the output negative pulse meets the requirements.

9. An airborne computer secondary power supply monitoring system, including: The first system module is used to configure a monitoring circuit for each of the power supplies, and different voltage thresholds are set. When the working voltage detected by the monitoring circuit corresponding to each power supply is greater than the corresponding threshold voltage, feedback is performed; the output end of the monitoring circuit of each power supply is connected to the input end of the first AND logic circuit; the output end of the first AND logic circuit is connected to the input end of the monostable flip-flop; The second system module is used such that the output end of the monostable flip-flop and the output end of the manual reset circuit both serve as the input ends of the second AND logic circuit. The manual reset circuit is used to output a low level for the manual reset signal HW_RESET when the manual reset switch is "ground"; and output a high level for the manual reset signal HW_RESET when the manual reset switch is "on". The third system module is used such that the output ends of the second AND logic circuit and the dog barking trigger reset conditioning circuit serve as the input ends of the third AND logic circuit, and the third AND logic circuit performs an output. Among them: for each of the power supply monitoring and dog barking trigger reset conditioning circuits, the result of performing an "AND" operation on all power supply monitoring outputs P_Monitor and the manual reset signal HW_RESET is used as the input of the monostable flip-flop. When either the power supply monitoring output or the manual reset signal is low, the monostable flip-flop outputs a low level; otherwise, it outputs a PWM wave with a determined duty cycle. The output of the monostable flip-flop serves as the signal output indicating whether each power supply is normally powered, and after performing an "AND" operation with the watchdog barking pulse, it serves as the reset signal for the airborne computer.

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