Multi-channel sensor signal acquisition device

Abstract

The utility model relates to the technical field of signal acquisition, in particular to a multipath sensor signal acquisition device, which comprises a main control chip, an analog-to-digital converter, a channel switching circuit, a plurality of sensors and a short circuit detection circuit, the output end of the analog-to-digital converter is connected with the input pin of the main control chip, and the input end of the analog-to-digital converter is connected with the output end of the short circuit detection circuit; the input end of the short-circuit detection circuit is connected with the output end of the channel switching circuit, and the input end of the channel switching circuit is connected with a plurality of sensors. And if the sensor is short-circuited and the output analog signal voltage exceeds the receiving range of the analog-to-digital converter, the short-circuit detection circuit sends a warning signal to the main control chip, and meanwhile, the input port of the analog voltage signal exceeding the range is grounded to release the voltage so as to protect a post-stage circuit. According to the utility model, the technical problem of potential damage caused by the fact that the output signal voltage exceeds the input voltage of the analog-to-digital converter when the multi-path sensor has a short-circuit fault is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of signal acquisition, in particular to a multi-channel sensor signal acquisition device. Background Art

[0002] With the rapid development of my country's aircraft industry, aircraft equipment is becoming more and more complete. Sensors are widely installed in aircraft to comprehensively monitor the flight status of the aircraft and ensure flight safety. However, the existing sensors use a single-channel data acquisition method, which makes the processing system unable to fully utilize system resources to process multiple sensors in parallel, reducing the overall performance and efficiency of the system. Therefore, it is extremely important to solve the problem of resource waste caused by the single-channel data acquisition method in a processing system with limited resources.

[0003] The patent name that has been published is a Chinese utility model patent with the publication number CN112622788A, which includes a microprocessor, an IO drive circuit, and a relay group. The utility model patent can collect multiple sensor signals in a short time, but the patent does not set a short-circuit detection circuit. If a short-circuit fault occurs in the sensor, its output signal voltage exceeds the input voltage limit of the analog-to-digital converter (ADC), which may cause damage to the ADC. Utility Model Content

[0004] The purpose of the present application is to provide a multi-channel sensor signal acquisition device, which solves the technical problem of potential damage caused by the output signal voltage exceeding the input voltage of the analog-to-digital converter when a short circuit occurs in the multi-channel sensor.

[0005] In order to solve the above technical problems, the solution adopted by this application is as follows:

[0006] The utility model provides a multi-channel sensor signal acquisition device, comprising a main control chip, an analog-to-digital converter, a channel switching circuit, and a plurality of sensors, wherein the output end of the analog-to-digital converter is connected to the main control chip, and the input end thereof is connected to the output end of the channel switching circuit, and the input end of the channel switching circuit is respectively connected to the output ends of the plurality of sensors; the utility model is characterized in that: a short-circuit detection circuit is also included; the output end of the channel switching circuit is connected to the analog-to-digital converter through the short-circuit detection circuit; the short-circuit detection circuit comprises an amplification circuit, a comparison circuit, a working circuit, and an alarm circuit;

[0007] The working circuit includes a relay, wherein a control input end of the relay is connected to an output end of a comparison circuit, and a signal channel is dynamically switched according to a result signal transmitted by the comparison circuit, and a control output end of the relay is grounded; a signal input end of the relay is connected to an output end of an amplifier circuit, a first signal output end of the relay is connected to a signal input end of an analog-to-digital converter, and a second signal output end of the relay is grounded;

[0008] When the result signal received by the control input end of the relay is a low-level signal, the relay does not switch the channel, and the signal received by the signal input end of the relay is output to the analog-to-digital converter through the first signal output end;

[0009] When the result signal received by the control input end of the relay is a high-level signal, the relay switches the signal channel, and the signal received by the relay input end is discharged to the ground end through the second signal output end;

[0010] The working circuit also includes a diode, and the control output end of the relay is grounded through the diode;

[0011] The input end of the amplifier circuit is connected to the output end of the channel switching circuit, and the output end of the amplifier circuit is respectively connected to the input end of the comparison circuit and the signal input end of the working circuit;

[0012] The input end of the alarm circuit is connected to the control output end of the relay, and the output end of the alarm circuit is connected to the input pin of the main control chip.

[0013] In some embodiments, the amplification circuit includes an operational amplifier, a signal input terminal of the operational amplifier is connected to the output terminal of the channel switching circuit, a second signal input terminal of the operational amplifier is connected to a reference voltage, and the output terminal of the operational amplifier outputs the amplified analog signal to the signal input terminal of a relay connected thereto.

[0014] In some embodiments, the comparison circuit includes a comparator, and the positive input terminal of the comparator performs a short circuit judgment after receiving a signal from an amplifier circuit connected to it, and the negative input terminal of the comparator receives a threshold voltage signal; the output terminal of the comparator outputs the result signal to the control input terminal of the working circuit connected to it.

[0015] In some embodiments, the alarm circuit includes a transistor; the base of the transistor is connected to the control output end of the relay, the emitter of the transistor is connected to the input pin of the main control chip, and the collector of the transistor is connected to the power supply.

[0016] In some embodiments, the alarm circuit further includes a photoelectric sensor, and the emitter of the transistor is connected to an input pin of a main control chip through the photoelectric sensor.

[0017] In some embodiments, the channel switching circuit includes a plurality of relays, the signal output ends of the plurality of relays are connected to form an output bus, the output bus is connected to the signal input end of the amplifying circuit; the signal input ends of the plurality of relays are respectively connected to the output ends of different sensors.

[0018] In some embodiments, the control input ends of the plurality of relays are respectively connected to the pins of the main control chip, and the control output ends of the plurality of relays are grounded.

[0019] In some embodiments, a delay circuit is further included, and the output end of the amplifier circuit is connected to the input end of the working circuit through the delay circuit.

[0020] In some embodiments, the main control chip is a FPGA chip.

[0021] The technical solution of the present application has at least the following advantages and beneficial effects:

[0022] The utility model is provided with a short-circuit detection circuit, which can monitor in real time whether the signal voltage of the sensor exceeds the input voltage of the analog-to-digital converter during the process of multi-channel sensor data collection. If it is determined that the signal voltage exceeds the input voltage, the input port of the analog voltage signal out of range is grounded to release the voltage, thereby protecting the subsequent circuit and improving the overall safety. The channel switching circuit provided in the utility model is composed of multiple relays connected in parallel, and the main control chip controls the switches of each relay to realize channel switching. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0024] Figure 2 This is a short circuit detection circuit diagram of the utility model;

[0025] Figure 3 Schematic diagram of the channel switching circuit in this embodiment. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] It should be noted that similar numbers and letters represent similar items in the following figures, so once an item is defined in one figure, it does not need to be further defined and explained in the subsequent figures. If the terms "center", "upper", "lower", "inner", "outer", etc. indicate an orientation or position relationship based on the orientation or position relationship shown in the figure, or the orientation or position relationship in which the product of the application is usually placed when in use, it is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present application. It should also be noted that unless otherwise clearly specified and limited, if the terms "set", "install", and "connect" appear, they should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be a connection between the two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0028] Example 1

[0029] Please refer to Figure 1-Figure 3 The utility model provides a multi-channel sensor signal acquisition device, which is the same as the prior art and includes a main control chip, an analog-to-digital converter, a channel switching circuit, and a plurality of sensors.

[0030] Several sensors, whose output ends are respectively connected to different input ends of the channel switching circuit, convert the external physical signal into an analog signal, and then transmit the analog signal to the channel switching circuit;

[0031] It should be noted that the sensors include speed sensors, altitude sensors, temperature sensors, and pressure sensors.

[0032] The channel switching circuit includes a plurality of relays, the signal input ends of the plurality of relays are respectively connected to the output ends of the plurality of sensors, the signal output ends of the plurality of relays are connected to form an output bus, the output bus is used as the output end of the channel switching circuit and is connected to the input end of the short circuit detection circuit; the control input ends of the plurality of relays are respectively connected to the pins of the main control chip, and the opening sequence of the plurality of relays is controlled by the main control chip;

[0033] Furthermore, in this embodiment, if Figure 3As shown, the channel switching circuit includes relays U5, U6, U7, and U8. Pin 5 of relay U5, pin 5 of relay U6, pin 5 of relay U7, and pin 5 of relay U8 are connected to form an output bus, which is called the out output terminal, and the out output terminal is connected to the input terminal of the analog-to-digital converter; Pin 2 of relay U5 is set to the in5 input terminal, which is used as the analog signal input terminal of the sensor and is connected to the first sensor; Pin 4 of relay U5 is set to the in1 input terminal, which is used as the control signal input terminal and is connected to the output port of the main control chip; Pin 1 of relay U5 is grounded; Pin 2 of relay U6 is set to the in6 input terminal, which is used as the analog signal input terminal of the sensor and is connected to the second sensor; Pin 4 of relay U6 is set to in2 input terminal, as the control signal input terminal, and is connected to the output port of the main control chip; Pin 1 of relay U6 is grounded; Pin 2 of relay U7 is set to in7 input terminal, as the analog signal input terminal of the sensor, and is connected to the third sensor; Pin 4 of relay U7 is set to in3 input terminal, as the control signal input terminal, and is connected to the output port of the main control chip; Pin 1 of relay U7 is grounded; Pin 2 of relay U8 is set to in8 input terminal, as the analog signal input terminal of the sensor, and is connected to the fourth sensor; Pin 4 of relay U8 is set to in4 input terminal, as the control signal input terminal, and is connected to the output port of the main control chip; Pin 1 of relay U8 is grounded.

[0034] It should be noted that the output ends of the main control chip connected to the in1 input end of relay U5, the in2 input end of relay U6, the in3 input end of relay U7, and the in4 input end of relay U8 are different output ends.

[0035] It should be noted that a working process of the channel switching circuit in this embodiment is as follows:

[0036] The main control chip controls the relay U5 to turn on, the signal transmission channel of the relay U5 is turned on, and the analog signal of the sensor connected to it is transmitted to the short-circuit detection circuit through the channel and the output bus;

[0037] After the transmission is completed, the channel of relay U5 is closed, the signal transmission channel of relay U6 is opened, and relay U6 repeats the working steps of relay U5;

[0038] After the transmission is completed, the channel of relay U6 is closed, the signal transmission channel of relay U7 is opened, and relay U7 repeats the working steps of relay U5;

[0039] After the transmission is completed, the channel of relay U7 is closed, the signal transmission channel of relay U8 is opened, and relay U8 repeats the working steps of relay U5;

[0040] After the transmission is completed, the relay U8 channel is closed, the signal transmission channel of relay U5 is opened, and the one-time working process of the channel switching circuit is completed.

[0041] The main control chip will control relay U5, relay U6, relay U7, and relay U8 to open and close in sequence and in a cycle in the above order, thereby ensuring that the analog signal of each sensor can be transmitted to the short-circuit detection circuit in an orderly manner.

[0042] The analog-to-digital converter has an output end connected to the main control chip and an input end connected to the output end of the channel switching circuit. The analog-to-digital converter processes the analog signal transmitted by the channel switching circuit into a digital signal, and transmits the digital signal to the main control chip after processing.

[0043] In this embodiment, the main control chip is a FPGA chip.

[0044] In this embodiment, a power module is also provided, which is respectively connected to the main control chip, the analog-to-digital converter, the channel switching circuit, the short-circuit detection circuit, and several sensors to provide power. The power module belongs to the prior art and will not be described in detail here.

[0045] Different from the prior art, it also includes a short-circuit detection circuit, which is arranged between the channel switching circuit and the analog-to-digital converter, that is, the output end of the channel switching circuit is connected to the analog-to-digital converter through the short-circuit detection circuit; after the short-circuit detection circuit receives the signal transmitted by the output bus of the channel switching circuit, it judges and processes the signal, and outputs the signal to the input end of the analog-to-digital converter after the processing is completed.

[0046] The short circuit detection circuit includes an amplifying circuit, a comparing circuit, a working circuit and an alarm circuit;

[0047] The working circuit includes a relay, a control input end of the relay is connected to an output end of the comparison circuit, a signal channel is dynamically switched according to a result signal transmitted by the comparison circuit, and a control output end of the relay is grounded; a signal input end of the relay is connected to an output end of the amplifier circuit, a first signal output end of the relay is connected to a signal input end of an analog-to-digital converter, and a second signal output end of the relay is grounded;

[0048] Further, when the result signal received by the control input terminal of the relay is a low-level signal, the relay does not switch the channel, and the signal received by the signal input terminal of the relay is output to the analog-to-digital converter through the first signal output terminal;

[0049] Furthermore, when the result signal received by the control input terminal of the relay is a high-level signal, the relay switches the signal channel, and the signal received by the input terminal of the relay is discharged to the ground terminal through the second signal output terminal.

[0050] The input end of the amplifier circuit is connected to the output end of the channel switching circuit, and the output end of the amplifier circuit is respectively connected to the input end of the comparison circuit and the signal input end of the working circuit;

[0051] The input end of the alarm circuit is connected to the control output end of the relay, and the output end of the alarm circuit is connected to the input pin of the main control chip.

[0052] Further, the short circuit detection circuit includes a photoelectric sensor U1, a relay U2, an operational amplifier U3, a comparator U4, a transistor Q1, a diode D1, capacitors C1 and C2, and resistors R1, R2, R3, R4, R5, R6, R7, R8, R9, and R10;

[0053] Furthermore, in the short-circuit detection circuit, one end of the resistor R1 is set as the IN input end, and the IN input end is connected to the output bus of the channel switching circuit; the other end of the resistor R1, pin 2 of the operational amplifier U3, one end of the resistor R2, and one end of the resistor R3 are connected, and the other end of the resistor R2 is connected to one end of the resistor R4 and connected to the power supply; pin 3 of the operational amplifier U3 is grounded, pin 4 is connected to the power supply, and pin 7 is grounded; the other end of the resistor R3, pin 3 of the comparator U4, pin 6 of the operational amplifier U3, one end of the resistor R5, and one end of the capacitor C1 are connected, the resistor R4 is connected to pin 2 of the comparator U4, pin 7 of the comparator U4 is grounded, and pin 4 is connected to the power supply; the other end of the capacitor C1 is grounded, and the other end of the resistor R5 is connected to pin 5 of the relay U2; pin 6 of the comparator U4 is connected to pin 4 of the relay U2, and pin 3 of the relay U2 is set to the OUT1 output end, OUT 1 output end is connected to the input end of the analog-to-digital converter; pin 2 of relay U2 is connected to one end of resistor R6, pin 1 of relay U2, and one end of the positive electrode of diode D1 and resistor R9 are connected, and the negative electrode of diode D1 is connected to the other end of resistor R6 and grounded; the other end of resistor R9 is connected to the base of transistor Q1, the collector of transistor Q1 is connected to one end of resistor R7, and the other end of resistor R7 is connected to one end of resistor R8 and connected to the power supply; the other end of resistor R8 is connected to pin 4 of photoelectric sensor U1; the emitter of transistor Q1 is connected to pin 1 of photoelectric sensor U1, pin 3 of photoelectric sensor U1, one end of capacitor C2, and one end of resistor R10 are connected, and the connection part is provided with output end OUT2, and output end OUT2 is connected to the input pin of the main control chip; pin 2 of photoelectric sensor U1, the other end of capacitor C2, and the other end of resistor R10 are connected and grounded.

[0054] Further, in the short-circuit detection circuit, the amplifying circuit includes an operational amplifier U3, resistors R1, R2, and R3; the amplifying circuit in this embodiment adopts an adder structure, a signal input terminal of the operational amplifier U3 is connected to the output terminal of the channel switching circuit, and a second signal input terminal of the operational amplifier is connected to a reference voltage. The operational amplifier adds and amplifies the signal of the first signal input terminal and the signal of the second signal input terminal to ensure that the amplified analog signal is suitable for the input range of the analog-to-digital converter; after the amplifying circuit amplifies the analog signal, the signal is transmitted to the signal input terminal of the relay U2 and the comparison circuit respectively;

[0055] It should be noted that the output end of the amplifier circuit is the output end of the operational amplifier U3, and the input end of the amplifier circuit is a signal input end, namely, the IN input end.

[0056] The comparison circuit includes a comparator U4 and a resistor R4; Pin 2 of the comparator U4, i.e., the negative input terminal, receives a threshold voltage signal; Pin 3 of the comparator U4, i.e., the positive input terminal, receives a voltage signal to be detected. When the amplifier circuit outputs the amplified analog signal to the positive input terminal, if the threshold voltage signal is greater than the analog signal, it means that the amplified analog signal does not exceed the input voltage range of the analog-to-digital sensor. At this time, Pin 6 of the comparator U4, i.e., the output terminal, outputs a low-level voltage to the working circuit, and the relay U2 in the working circuit does not switch channels; if the threshold voltage signal is less than the analog signal, it means that the amplified analog signal exceeds the input voltage range of the analog-to-digital sensor. At this time, Pin 6 of the comparator U4 outputs a high-level voltage to the working circuit, and the relay U2 in the working circuit switches channels;

[0057] It should be noted that the input end of the comparison circuit is the positive input end of the comparator U4, connected to the output end of the amplifier circuit; the output end of the comparison circuit is the output end of the comparator U4, connected to the control input end of the working circuit.

[0058] The working circuit includes relay U2, resistors R5 and R6, capacitor C1, and diode D1; the function of diode D1 is to prevent current backflow, and the function of relay U2 is to switch the signal input channel; if the voltage of the amplified analog signal does not exceed the input voltage of the analog-to-digital converter, the amplified analog signal is output to the analog-to-digital converter through relay U2; if the voltage of the amplified analog signal exceeds the input voltage of the analog-to-digital converter, relay U2 grounds the output port according to the output signal of the comparison circuit, and at this time, the analog voltage signal that exceeds the range is effectively released, thereby protecting the subsequent circuit;

[0059] It should be noted that the first signal output end of relay U2 in the working circuit is the OUT1 output end, the second signal output end is the pin 2 port of relay U2, the control input end is pin 4 of relay U2, and the control output end is pin 1 of relay U2; the signal input end of relay U2 is pin 1 of relay U2, and this signal output end is the input end of the working circuit.

[0060] The utility model is also provided with a delay circuit, through which the output end of the amplifier circuit is connected to the input end of the working circuit; the delay circuit is an RC delay circuit, which includes a resistor R5 and a capacitor C1; the function of the RC delay circuit is to delay the time for the analog signal to travel from the output end of the amplifier circuit to the analog-to-digital converter, so that the working circuit first receives the signal from the comparison circuit and switches the signal transmission channel before transmitting the data;

[0061] It should be noted that the portion where one end of the resistor R5 is connected to one end of the capacitor C1 is defined as the input end of the delay circuit, and the other end of the resistor R5 is defined as the output end of the delay circuit.

[0062] The alarm circuit includes a photoelectric sensor U1, a transistor Q1, a diode D1, a capacitor C1, and resistors R7, R8, R9, and R10; the capacitor C1 is used for filtering, and the transistor Q1 is used as a switch to turn on the alarm circuit. The photoelectric sensor U1 can realize non-contact signal transmission, providing protection for the receiving end of the main control chip. When the relay U2 in the working circuit switches the signal transmission channel and grounds the output port, the working circuit controls the transistor Q1 in the alarm circuit to turn on, so that the transmitting end of the photoelectric sensor U1 is powered on and emits a light signal. After the receiving end of the photoelectric sensor U1 receives the light signal, the circuit where the receiving end is located is turned on, and the alarm circuit sends an alarm signal to the input pin of the main control chip connected to it through the OUT2 end. The main control chip sends an alarm message to the monitoring end based on this signal.

[0063] It should be noted that the input end of the alarm circuit is the base of the transistor Q1, and the output end of the alarm circuit is the output end OUT2.

[0064] So far, various embodiments of the present invention have been described in detail. In order to avoid obscuring the concept of the present invention, some details known in the art are not described. Based on the above description, those skilled in the art can fully understand how to implement the technical solution of the present invention, and the scope of the present invention is defined by the attached claims.

Claims

1. A multi-channel sensor signal acquisition device, comprising a main control chip, an analog-to-digital converter, a channel switching circuit, and a plurality of sensors, wherein the output end of the analog-to-digital converter is connected to the main control chip, and the input end thereof is connected to the output end of the channel switching circuit, and the input end of the channel switching circuit is respectively connected to the output ends of a plurality of sensors; characterized in that: It also includes a short-circuit detection circuit; the output end of the channel switching circuit is connected to the analog-to-digital converter through the short-circuit detection circuit; the short-circuit detection circuit includes an amplification circuit, a comparison circuit, a working circuit, and an alarm circuit; The working circuit includes a relay, wherein a control input end of the relay is connected to an output end of a comparison circuit, and a signal channel is dynamically switched according to a result signal transmitted by the comparison circuit, and a control output end of the relay is grounded; a signal input end of the relay is connected to an output end of an amplifier circuit, a first signal output end of the relay is connected to a signal input end of an analog-to-digital converter, and a second signal output end of the relay is grounded; When the result signal received by the control input end of the relay is a low-level signal, the relay does not switch the channel, and the signal received by the signal input end of the relay is output to the analog-to-digital converter through the first signal output end; When the result signal received by the control input end of the relay is a high-level signal, the relay switches the signal channel, and the signal received by the relay input end is discharged to the ground end through the second signal output end; The working circuit also includes a diode, and the control output end of the relay is grounded through the diode; The input end of the amplifier circuit is connected to the output end of the channel switching circuit, and the output end of the amplifier circuit is respectively connected to the input end of the comparison circuit and the signal input end of the working circuit; The input end of the alarm circuit is connected to the control output end of the relay, and the output end of the alarm circuit is connected to the input pin of the main control chip.

2. The multi-channel sensor signal acquisition device according to claim 1, characterized in that: The amplification circuit includes an operational amplifier, a signal input terminal of the operational amplifier is connected to the output terminal of the channel switching circuit, a second signal input terminal of the operational amplifier is connected to a reference voltage, and the output terminal of the operational amplifier outputs the amplified analog signal to the signal input terminal of a relay connected thereto.

3. The multi-channel sensor signal acquisition device according to claim 1, characterized in that: The comparison circuit includes a comparator, wherein the positive input terminal of the comparator performs short circuit judgment after receiving a signal from an amplifier circuit connected thereto, and the negative input terminal of the comparator receives a threshold voltage signal; the output terminal of the comparator outputs a result signal to a control input terminal of a working circuit connected thereto.

4. The multi-channel sensor signal acquisition device according to claim 1, characterized in that: The alarm circuit comprises a transistor; the base of the transistor is connected to the control output end of the relay, the emitter of the transistor is connected to the input pin of the main control chip, and the collector of the transistor is connected to the power supply.

5. The multi-channel sensor signal acquisition device according to claim 4, characterized in that: The alarm circuit also includes a photoelectric sensor, and the emitter of the transistor is connected to the input pin of the main control chip through the photoelectric sensor.

6. The multi-channel sensor signal acquisition device according to claim 1, characterized in that: The channel switching circuit includes a plurality of relays, the signal output ends of the plurality of relays are connected to form an output bus, the output bus is connected to the signal input end of the amplifier circuit; the signal input ends of the plurality of relays are respectively connected to the output ends of different sensors.

7. The multi-channel sensor signal acquisition device according to claim 6, characterized in that: The control input ends of the plurality of relays are respectively connected to the pins of the main control chip, and the control output ends of the plurality of relays are grounded.

8. The multi-channel sensor signal acquisition device according to claim 1, characterized in that: It also includes a delay circuit, and the output end of the amplifier circuit is connected to the input end of the working circuit through the delay circuit.

9. The multi-channel sensor signal acquisition device according to claim 1, characterized in that: The main control chip is a FPGA chip.

Images