Double-wire sensor control circuit
By designing a dual-wire sensor control circuit, the combination of sensor access module, adjustment module, digital-to-analog conversion module and current conversion module is solved, and flexible control and low-power adjustment of various types of sensors are achieved.
Patent Information
- Application Number
- CN202422112023.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-29
- Publication Date
- 2025-05-27
- Estimated Expiration
- 2034-08-29
AI Technical Summary
The existing sensor control system mainly uses four wires for adjustment, and cannot realize dual-wire sensor control, which limits the flexibility and application range of the sensor.
A two-wire sensor control circuit is designed, and the sensor signal is collected, adjusted and converted through the combination of sensor access module, adjustment module, digital-to-analog conversion module and current conversion module, and the current signal is adjusted using 4-20mA.
The dual-wire control of various types of sensors is realized, reducing the number and cost of wire connections, improving anti-interference ability, and maintaining low power consumption during the adjustment process.
Smart Images
Figure CN222914087U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of sensor control, and particularly relates to a two-wire sensor control circuit. Background Technique
[0002] The control and adjustment of sensors mainly involve the processing of the output signals of sensors and the adjustment of the sensitivity or working parameters of sensors according to specific requirements. The control and adjustment of sensors are key steps to ensure that sensors can accurately and effectively complete measurement and control tasks.
[0003] At present, only some temperature and humidity, pressure, and rotational speed sensors on the market are industrial 4-20mA two-wire adjustable, and there are still no two-wire products for other types of sensors. When controlling and regulating such sensors, four wires are required to achieve the control and adjustment of the sensors. Content of the Utility Model
[0004] Purpose of the utility model: To provide a two-wire sensor control circuit, which solves the above problems existing in the prior art.
[0005] Technical solution: A two-wire sensor control circuit includes a sensor connection module. The input end of the sensor access module is connected to an external sensor, and the output end of the sensor access module is connected to the input end of an adjustment module. The adjustment module is used to receive and adjust the values of the external sensor. The output end of the adjustment module is connected to the input end of a digital-to-analog conversion module. The digital-to-analog conversion module is used to convert the received signal into a digital signal. The output end of the digital-to-analog conversion module is connected to the input end of a current conversion module. The current conversion module is used to convert the digital signal into a current signal. The output end of the current conversion module is connected to the output end of the sensor connection module.
[0006] Preferably, the adjustment module includes an access switch SW1, a chip U2, a crystal oscillator Y1, a capacitor C5, and a capacitor C6. The pin 4 of the access switch SW1 is connected to the pin 20 of the chip U2, the pin 5 of the access switch SW1 is connected to the pin 19 of the chip U2, the pin 1 of the crystal oscillator Y1 is simultaneously connected to the pin 2 of the chip U2 and one end of the capacitor C5, the other end of the capacitor C5 is grounded, the pin 3 of the crystal oscillator Y1 is simultaneously connected to the pin 3 of the chip U2 and one end of the capacitor C6, the other end of the capacitor C6 is grounded, and the pin 2 of the crystal oscillator Y1 is grounded.
[0007] Preferably, the digital-to-analog conversion module includes chip U5, resistor R1, resistor R8, resistor R9, resistor R10, resistor R11, resistor R12, and capacitor C7. One end of resistor R1 is connected to pin 1 of chip U5. One end of resistor R8 is connected to pin 6 of chip U5, and the other end of resistor R8 is simultaneously connected to resistor R9, resistor R10, resistor R11, and resistor R12. The other end of resistor R11 is connected to an external 2.5V power supply. The other end of resistor R9 is connected to pin 5 of chip U5. The other end of resistor R10 is connected to pin 4 of chip U5. The other end of resistor R12 is connected to an external 3.3V power supply. One end of capacitor C7 is simultaneously connected to pin 3 of chip U5 and resistor R10, and the other end of capacitor C7 is grounded. Pin 6 of chip U5 is connected to pin 18 of chip U2. Pin 5 of chip U5 is connected to pin 17 of chip U2. Pin 4 of chip U5 is connected to pin 13 of chip U2.
[0008] Preferably, the current conversion module includes chip U3, triode Q2, zener diode ZD1, rectifier bridge BD1, and capacitor C1. The base of triode Q2 is connected to pin 6 of chip U3. The emitter of triode Q2 is connected to pin 5 of chip U3. The collector of diode Q2 is simultaneously connected to capacitor C1 and pin 7 of chip U3. Zener diode ZD1 and capacitor C1 are connected in parallel with each other. The positive electrode of zener diode ZD1 is connected to pin 4 of chip U3 and pin 3 of rectifier bridge BD1. The negative electrode of zener diode ZD1 is connected to pin 7 of chip U3 and pin 4 of rectifier bridge BD1. Pin 2 of the rectifier bridge is connected to the sensor connection module. Pin 2 of chip U3 is connected to the output end of the digital-to-analog conversion.
[0009] Preferably, the sensor connection module includes interface P2 and interface P3. Pin 1 of interface P2 is connected to pin 12 of chip U2. Pin 2 of interface P2 is connected to pin 11 of chip U2. Pin 1 of interface P3 is connected to the power supply. Pin 2 of interface P3 is grounded.
[0010] Preferably, the crystal oscillator Y1 uses a crystal oscillator of the 25MHZ model, and chip U2 uses a chip of the STM32F030F4P6 model.
[0011] Preferably, chip U5 uses a chip of the DAC7512 model.
[0012] Preferably, chip U3 uses a chip of the XTR115U model.
[0013] Beneficial effects: The present utility model relates to a two-wire sensor control circuit. The sensor access module can access various types of sensor signals. The chip U2 in the adjustment module is used to collect signals from the accessed sensors. The chip U5 in the digital-to-analog conversion module adjusts the current loop to 4 - 20 mA. By using a 4 - 20 mA adjustment range, the safety during the on-off process of the current in the detection process is improved. At the same time, the anti-interference ability is enhanced by using the current signal adjustment method.
[0014] During the adjustment process, the overall power consumption is kept within 4 mA. This low-power mode can meet various types of two-wire sensors. It not only reduces the number of wire connections and costs, but also can be applied to sensors with various different wiring methods. Description of the Drawings
[0015] Figure 1 It is the circuit diagram of the adjustment module of the present utility model;
[0016] Figure 2 It is the circuit diagram of the current conversion module of the present utility model;
[0017] Figure 3 It is the circuit diagram of the digital-to-analog conversion module of the present utility model;
[0018] Figure 4 It is the circuit diagram of the sensor connection module of the present utility model. Detailed Embodiment
[0019] As Figures 1 to 4 shown, the present utility model provides a technical solution: a two-wire sensor control circuit, including a sensor connection module. The input end of the sensor access module is connected to an external sensor, and the output end of the sensor access module is connected to the input end of the adjustment module. The adjustment module is used to receive and adjust the values of the external sensors. The output end of the adjustment module is connected to the input end of the digital-to-analog conversion module. The digital-to-analog conversion module is used to convert the received signal into a digital signal. The output end of the digital-to-analog conversion module is connected to the input end of the current conversion module. The current conversion module is used to convert the digital signal into a current signal. The output end of the current conversion module is connected to the output end of the sensor connection module. The sensor access module can access various types of sensor signals. It cooperates with the adjustment module to collect and adjust the signals of the accessed sensors. The digital-to-analog conversion module adjusts the current loop to 4 - 20 mA. By using a 4 - 20 mA adjustment range, the safety during the on-off process of the current in the detection process is improved. At the same time, the anti-interference ability is enhanced by using the current signal adjustment method. During the adjustment process, the overall power consumption is kept within 4 mA. This low-power mode can meet various types of two-wire sensors. It not only reduces the number of wire connections and costs, but also can be applied to sensors with various different wiring methods.
[0020] In a further embodiment, as Figure 1 shown, the adjustment module includes an access switch SW1, a chip U2, a crystal oscillator Y1, a capacitor C5, and a capacitor C6. The pin 4 of the access switch SW1 is connected to the pin 20 of the chip U2. By controlling the access switch SW1, the on / off of the entire circuit is controlled. The pin 5 of the access switch SW1 is connected to the pin 19 of the chip U2. The pin 1 of the crystal oscillator Y1 is simultaneously connected to the pin 2 of the chip U2 and one end of the capacitor C5. The other end of the capacitor C5 is grounded. The pin 3 of the crystal oscillator Y1 is simultaneously connected to the pin 3 of the chip U2 and one end of the capacitor C6. The other end of the capacitor C6 is grounded. The pin 2 of the crystal oscillator Y1 is grounded. Among them, the crystal oscillator Y1 uses a crystal oscillator of the 25MHZ model, and the chip U2 uses a chip of the STM32F030F4P6 model. The sensor connection module includes an interface P2 and an interface P3. The pin 1 of the interface P2 is connected to the pin 12 of the chip U2. The pin 2 of the interface P2 is connected to the pin 11 of the chip U2. The pin 1 of the interface P3 is connected to the power supply. The pin 2 of the interface P3 is grounded. Detection is performed by connecting an external sensor through the interface P2, and adjustment of the external sensor is achieved through the interface P3.
[0021] In a further embodiment, as Figure 3 shown, the digital-to-analog conversion module includes a chip U5, a resistor R1, a resistor R8, a resistor R9, a resistor R10, a resistor R11, a resistor R12, and a capacitor C7. The chip U5 uses a chip of the DAC7512 model. The resistor R1 is connected to the pin 1 of the chip U5. One end of the resistor R8 is connected to the pin 6 of the chip U5. The other end of the resistor R8 is simultaneously connected to the resistor R9, the resistor R10, the resistor R11, and the resistor R12. The other end of the resistor R11 is connected to an external 2.5V power supply. The other end of the resistor R9 is connected to the pin 5 of the chip U5. The other end of the resistor R10 is connected to the pin 4 of the chip U5. The other end of the resistor R12 is connected to an external 3.3V power supply. One end of the capacitor C7 is simultaneously connected to the pin 3 of the chip U5 and the resistor R10. The other end of the capacitor C7 is grounded. The pin 6 of the chip U5 is connected to the pin 18 of the chip U2. The pin 5 of the chip U5 is connected to the pin 17 of the chip U2. The pin 4 of the chip U5 is connected to the pin 13 of the chip U2.
[0022] In a further embodiment, as Figure 2As shown, the current conversion module includes a chip U3, a triode Q2, a zener diode ZD1, a rectifier bridge BD1, and a capacitor C1. The chip U3 is a chip of the XTR115U model. The base of the triode Q2 is connected to pin 6 of the chip U3. The emitter of the triode Q2 is connected to pin 5 of the chip U3. The collector of the diode Q2 is connected to both the capacitor C1 and pin 7 of the chip U3. The zener diode ZD1 is connected in parallel with the capacitor C1. The positive electrode of the zener diode ZD1 is connected to pin 4 of the chip U3 and pin 3 of the rectifier bridge BD1. The negative electrode of the zener diode ZD1 is connected to pin 7 of the chip U3 and pin 4 of the rectifier bridge BD1. Pin 2 of the rectifier bridge is connected to the sensor connection module. Pin 2 of the chip U3 is connected to the output end of the digital-to-analog conversion.
[0023] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all belong to the protection scope of the present invention.
Claims
1. A two-wire sensor control circuit, characterized in that: It includes a sensor access module, the input end of the sensor access module is connected to the external sensor, the output end of the sensor access module is connected to the input end of the adjustment module, the adjustment module is used to adopt and adjust the numerical value received from the external sensor, the output end of the adjustment module is connected to the input end of the digital-to-analog conversion module, the digital-to-analog conversion module is used to convert the received signal into a digital signal, the output end of the digital-to-analog conversion module is connected to the input end of the current conversion module, the current conversion module is used to convert the digital signal into a current signal, and the output end of the current conversion module is connected to the output end of the sensor connection module.
2. A two-wire sensor control circuit according to claim 1, characterized in that: The regulation module includes an access switch SW1, a chip U2, a crystal oscillator Y1, a capacitor C5 and a capacitor C6, wherein pin 4 of the access switch SW1 is connected to pin 20 of the chip U2, pin 5 of the access switch SW1 is connected to pin 19 of the chip U2, pin 1 of the crystal oscillator Y1 is simultaneously connected to pin 2 of the chip U2 and one end of the capacitor C5, and the other end of the capacitor C5 is grounded, pin 3 of the crystal oscillator Y1 is simultaneously connected to pin 3 of the chip U2 and one end of the capacitor C6, and the other end of the capacitor C6 is grounded, and pin 2 of the crystal oscillator Y1 is grounded.
3. A two-wire sensor control circuit according to claim 1, characterized in that: The digital-to-analog conversion module includes a chip U5, a resistor R1, a resistor R8, a resistor R9, a resistor R10, a resistor R11, a resistor R12 and a capacitor C7, wherein the resistor R1 is connected to pin 1 of the chip U5, one end of the resistor R8 is connected to pin 6 of the chip U5, the other end of the resistor R8 is simultaneously connected to resistors R9, resistor R10, resistor R11 and resistor R12, the other end of the resistor R11 is connected to an external 2.5V power supply, the other end of the resistor R9 is connected to pin 5 of the chip U5, the other end of the resistor R10 is connected to pin 4 of the chip U5, the other end of the resistor R12 is connected to an external 3.3V power supply, one end of the capacitor C7 is simultaneously connected to pin 3 of the chip U5 and the resistor R10, the other end of the capacitor C7 is grounded, pin 6 of the chip U5 is connected to pin 18 of the chip U2, pin 5 of the chip U5 is connected to pin 17 of the chip U2, and pin 4 of the chip U5 is connected to pin 13 of the chip U2.
4. A two-wire sensor control circuit according to claim 1, characterized in that: The current conversion module includes a chip U3, a transistor Q2, a voltage-stabilizing diode ZD1, a rectifier bridge BD1 and a capacitor C1. The base of the transistor Q2 is connected to pin 6 of the chip U3, the emitter of the transistor Q2 is connected to pin 5 of the chip U3, the collector of the diode Q2 is simultaneously connected to capacitor C1 and pin 7 of the chip U3, the voltage-stabilizing diode ZD1 and the capacitor C1 are connected in parallel, the positive electrode of the voltage-stabilizing diode ZD1 is connected to pin 4 of the chip U3 and pin 3 of the rectifier bridge BD1, the negative electrode of the voltage-stabilizing diode ZD1 is connected to pin 7 of the chip U3 and pin 4 of the rectifier bridge BD1, pin 2 of the rectifier bridge is connected to the sensor connection module, and pin 2 of the chip U3 is connected to the output end of the digital-to-analog conversion.
5. A two-wire sensor control circuit according to claim 1, characterized in that: The sensor connection module includes an interface P2 and an interface P3, wherein pin 1 of the interface P2 is connected to pin 12 of the chip U2, pin 2 of the interface P2 is connected to pin 11 of the chip U2, pin 1 of the interface P3 is connected to a power source, and pin 2 of the interface P3 is grounded.
6. A two-wire sensor control circuit according to claim 2, characterized in that: The crystal oscillator Y1 adopts a 25MHZ crystal oscillator, and the chip U2 adopts a STM32F030F4P6 chip.
7. A two-wire sensor control circuit according to claim 3, characterized in that: The chip U5 is a DAC7512 chip.
8. A two-wire sensor control circuit according to claim 4, characterized in that: The chip U3 is a chip of the XTR115U model.