Multi-channel data acquisition and wireless transmission control system

Abstract

The utility model belongs to the technical field of electronic circuits, and particularly relates to a multichannel data acquisition and wireless transmission control system. Comprising a main control unit, a signal amplification unit, a power management unit, a wireless communication unit, an analog-to-digital conversion unit, a relay control unit and a power supply unit. The power supply unit converts an external input power supply into a system working voltage; the power supply management unit is connected with the power supply unit, and distributes and converts the working voltage of the system into a working power supply required by each functional unit; the main control unit is respectively connected with the analog-to-digital conversion unit and the wireless communication unit; the signal amplification unit is connected between the input end of the sensor and the analog-to-digital conversion unit; and the relay control unit is connected with the main control unit and is used for realizing on-off control of external equipment according to a control signal of the main control unit. Through cooperation of AMS1117 and ICL7660, multi-voltage output of + / -2.5 V, 3.3 V and 5V is provided, and requirements of different modules are met. And multi-sensor parallel acquisition is supported, and signal crosstalk is reduced.

Description

TECHNICAL FIELD

[0001] The utility model belongs to electronic circuit technical field especially relates to a kind of multi-channel data acquisition and wireless transmission control system. BACKGROUND

[0002] The existing data acquisition system often has the following problems:

[0003] 1. Insufficient signal accuracy: traditional amplifier circuit has poor noise suppression ability, which affects the sensor signal acquisition accuracy;

[0004] 2. Single power management: voltage matching is difficult when multiple modules are powered, which can easily introduce interference;

[0005] 3. Low wireless communication stability: existing wireless modules have insufficient anti-interference design and are easily affected by environmental factors;

[0006] 4. Traditional relay drive circuit lacks effective isolation, which can easily cause electromagnetic interference to the data acquisition circuit. SUMMARY

[0007] The utility model provides a kind of multi-channel data acquisition and wireless transmission control system to the defects existing in prior art.

[0008] To achieve the above purpose, the utility model adopts the following technical solutions: a multi-channel data acquisition and wireless transmission control system includes a master control unit, a signal amplification unit, a power management unit, a wireless communication unit, an analog-digital conversion unit, a relay control unit and a power supply unit.

[0009] The power supply unit converts external input power into system operating voltage.

[0010] The power management unit is connected to the power supply unit, and the system operating voltage is distributed and converted into the operating power required by each functional unit.

[0011] The master control unit is connected to the analog-digital conversion unit and the wireless communication unit.

[0012] The signal amplification unit is connected between the sensor input end and the analog-digital conversion unit.

[0013] The relay control unit is connected to the master control unit and is used to realize the on-off control of external equipment according to the control signal of the master control unit.

[0014] Further, the master control unit uses an ESP32-WROOM-32UE-N4 module, the master control unit is connected to the analog-digital conversion unit through an SPI interface, and is connected to the wireless communication unit through a serial port.

[0015] Further, the signal amplification unit comprises three AD620 instrument amplifiers, the input end of each AD620 instrument amplifier is connected in series with a resistor and in parallel with a capacitor to ground, forming an RC filter circuit, the feedback end of each AD620 instrument amplifier is connected to a variable potentiometer, and the output end of each AD620 instrument amplifier is connected in series with a current-limiting resistor.

[0016] Further, the input end of the AD620 instrument amplifier is connected in series with a 10K resistor and in parallel with a 1uF capacitor, the feedback end of the AD620 instrument amplifier is connected to a 10KΩ potentiometer, and the output end of the AD620 instrument amplifier is connected in series with a 100Ω resistor.

[0017] Further, the power management unit comprises:

[0018] a 3.3V step-down circuit for supplying power to the main control unit and peripheral circuits, and the input of the 3.3V step-down circuit is connected to the output of the power supply unit;

[0019] a 2.5V reference voltage circuit for generating a 2.5V reference voltage, and the input of the 2.5V reference voltage circuit is connected to the output of the power supply unit;

[0020] a negative voltage generation circuit for providing a negative power supply for the signal amplification unit, the input of the negative voltage generation circuit is connected to the output of the 2.5V reference voltage circuit, and the output of the negative voltage generation circuit is connected to the signal amplification unit.

[0021] Further, the 3.3V step-down circuit uses AMS1117-3.3, the 2.5V reference voltage circuit uses AMS1117-2.5, and the negative voltage generation circuit uses ICL7660 charge pump.

[0022] Further, the wireless communication unit uses E70-433NW30S module, and each input and output pin is connected in series with a protection resistor.

[0023] Further, the analog-to-digital conversion unit uses a 24-bit ADS1220 chip, the digital supply voltage of which is 3.3V, and the analog supply voltage of which is ±2.5V.

[0024] Further, the relay control unit uses an optocoupler isolation drive circuit, a transistor drive circuit, a relay, and a freewheeling protection circuit, wherein the optocoupler isolation drive circuit is used to achieve electrical isolation between the main control unit and the relay; the transistor drive circuit is used to amplify the control signal to drive the relay; the relay is used to control the power on-off of the external device; the freewheeling protection circuit is used to eliminate the reverse electromotive force of the relay coil; the optocoupler isolation drive circuit uses PC817 optocoupler, the transistor drive circuit uses S8050 transistor, and the freewheeling protection circuit uses 1N4007 diode connected in parallel across the relay coil.

[0025] Further, the power supply unit comprises a switching power supply, a fuse and a pressure sensitive resistor are arranged at an input end of the switching power supply, and the input end of the switching power supply is filtered by an inductor and a safety capacitor, high and low frequency filter capacitors are connected in parallel at an output end of the switching power supply, and the output (5V voltage) of the switching power supply is connected with inputs of 3.3V voltage reduction circuit and 2.5V reference voltage circuit respectively.

[0026] Compared with the prior art, the utility model has beneficial effects.

[0027] The utility model discloses a cooperation of AMS1117 and ICL7660 provides + 2.5V, 3.3V, 5V multi -voltage output, satisfies different module demand, and adopts AD620ANZ three -way configuration, supports multiple sensor parallel acquisition, reduces signal crosstalk, still through double wireless communication redundancy: ESP32 (2.4GHz) and E70 (433MHz) dual -mode module cooperation, adapts complex communication environment, and the relay control adopts the optical coupling isolation, avoids the interference of strong electricity to weak electric circuit. BRIEF DESCRIPTION OF DRAWINGS

[0028] The utility model makes further explanation to the utility model with combining with the drawings and specific embodiment. The utility model protection scope is not only limited to the following content's expression.

[0029] Figure 1 It is the principle diagram of the utility model.

[0030] Figure 2 It is the ESP32 master unit of the utility model.

[0031] Figure 3 It is three -way AD620 amplification unit of the utility model.

[0032] Figure 4 It is double AMS1117 voltage reduction unit of the utility model.

[0033] Figure 5 It is ICL7660 negative pressure unit of the utility model.

[0034] Figure 6 It is E70 wireless communication unit of the utility model.

[0035] Figure 7 It is ADS1220 analog quantity acquisition unit of the utility model.

[0036] Figure 8 It is relay control unit of the utility model.

[0037] Figure 9 It is power supply unit of the utility model. SPECIFIC EMBODIMENT

[0038] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0039] The terminology used in the embodiments of this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure. The singular forms “a,” “the,” and “the” as used in the embodiments of this disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0040] Depending on the context, words such as “if” or “suppose” used here can be interpreted as “when”, “in response to determination”, or “in response to detection”.

[0041] For ease of understanding, the embodiments of this disclosure will be described in detail first.

[0042] like Figures 1-9 As shown, the multi-channel data acquisition and wireless transmission control system includes a main control unit, a signal amplification unit, a power management unit, a wireless communication unit, an analog-to-digital converter, a relay control unit, and a power supply unit. The power supply unit converts external input power into the system operating voltage. The power management unit is connected to the power supply unit and distributes the system operating voltage to the operating power required by each functional unit. The main control unit is connected to the analog-to-digital converter and the wireless communication unit. The signal amplification unit is connected between the sensor input terminal and the analog-to-digital converter. The relay control unit is connected to the main control unit and is used to control the switching of external devices according to the control signals from the main control unit.

[0043] Preferably, the main control unit adopts the ESP32-WROOM-32UE-N4 module. The main control unit is connected to the analog-to-digital converter unit via the SPI interface and to the wireless communication unit via the serial port. Specifically, the domestically produced ESP32-WROOM-32UE-N4 module is selected for data acquisition, processing, and 2.4G wireless communication with the host computer. The SPI interface is connected to the ADS1220 analog signal acquisition unit, the serial port is connected to the E70 wireless communication unit, and IO13, IO14, and IO15 are directly connected to the 18B20 temperature sensor to read the temperature.

[0044] Preferably, the signal amplification unit comprises three AD620 instrument amplifiers, the input end of each AD620 instrument amplifier is connected in series with a resistor and in parallel with a capacitor to ground, forming an RC filter circuit, the feedback end of each AD620 instrument amplifier is connected to an adjustable potentiometer, and the output end of each AD620 instrument amplifier is connected in series with a current-limiting resistor. The input end of the AD620 instrument amplifier is connected in series with a 10K resistor and in parallel with a 1uF capacitor, the feedback end of the AD620 instrument amplifier is connected to a 10KΩ potentiometer, and the output end of the AD620 instrument amplifier is connected in series with a 100Ω resistor and finally connected to an analog-to-digital conversion unit ADS1220 chip, wherein RL1 is connected to pin 11 of the ADS1220 chip, RL2 is connected to pin 10 of the ADS1220 chip, and RL3 is connected to pin 7 of the ADS1220 chip. The input of each AD620 instrument amplifier, such as RL1-, RL1+, is used to connect a sensor.

[0045] Specifically, a low-drift, low-power instrument amplifier chip AD620 is used, which is powered by ±2.5V dual power supply, connected in series with a 10K resistor at the input end, and connected in parallel with a 1UF capacitor to GND to form an RC filter with a cutoff frequency of 15.9Hz, connected to a 10KΩ potentiometer at the feedback end for adjusting the amplification factor, and connected in series with a 100Ω resistor at the output end for reducing output ripple.

[0046] Preferably, the power management unit comprises a 3.3V step-down circuit for powering the main control unit and peripheral circuits; the 3.3V step-down circuit uses AMS1117-3.3, the 2.5V reference voltage circuit uses AMS1117-2.5, and the negative voltage generation circuit uses ICL7660 charge pump. It also includes a 2.5V reference voltage circuit; wherein the 3.3V step-down circuit and the 2.5V reference voltage circuit constitute a dual AMS1117 step-down unit composed of AMS117-3.3 and AMS1117-2.5, and a 100nf and a 1uf capacitor are connected in parallel at the input and output ends respectively for reducing output ripple. The power management unit also includes a negative voltage generation circuit for providing negative power supply for the signal amplification unit.

[0047] A possible embodiment, AMS1117-3.3 reduces 5V to 3.3V to power the main control and peripheral circuits; AMS1117-2.5 generates a 2.5V reference voltage; ICL7660 charge pump generates -2.5V negative voltage to provide symmetrical power supply for the operational amplifier.

[0048] The power management unit also includes a negative voltage generation circuit, which uses an ICL7660 charge pump voltage conversion chip, and a 10UF tantalum capacitor is connected in parallel at the output end and feedback end for reducing output ripple.

[0049] Preferably, the wireless communication unit adopts E70-433NW30S module, and each input and output pin is connected in series with a protection resistor. Among them, the wireless communication unit adopts a high-power 433MHz wireless communication module E70-433NW30S, the communication transmission power peak power can reach 1W, and it supports multiple lower computers data concurrency at the same time. The serial port is connected with the main control ESP32, the LINK, ACK and AUX outputs are used for external state indication, and each input and output pin is connected in series with a 1KΩ resistor for protecting the module. The E70-433NW30S module is connected with the main control through the UART interface, and realizes 433MHz remote data transmission.

[0050] Preferably, the analog-to-digital conversion unit adopts a 24-bit ADS1220 chip, the digital supply voltage of which is 3.3V, and the analog supply voltage of which is ±2.5V. The chip is a low-power, high-precision 24-bit ADC acquisition chip, and the ADS1220 acquires three voltages amplified by the AD620, and communicates with the main control ESP32 through the SPI interface. The digital supply voltage of the chip is 3.3V, the analog supply voltage is ±2.5V, and the acquisition range is ±2.5V.

[0051] Preferably, the relay control unit adopts an optocoupler isolation drive circuit, a transistor drive circuit, a relay, and a freewheeling protection circuit. The optocoupler isolation drive circuit is used to realize the electrical isolation between the main control unit and the relay; the transistor drive circuit is used to amplify the control signal to drive the relay; the relay is used to control the power on-off of the external equipment; and the freewheeling protection circuit is used to eliminate the reverse electromotive force of the relay coil. The optocoupler isolation drive circuit adopts PC817 optocoupler, the transistor drive circuit adopts S8050 transistor, and the freewheeling protection circuit adopts 1N4007 diode connected in parallel across the relay coil.

[0052] And a freewheeling diode is connected in parallel across the relay coil. The relay control unit is a classic optocoupler relay control circuit, which is attracted at high level and is disconnected at low level.

[0053] Another possible embodiment adopts optocoupler PC817 and transistor SS8050 to ensure switching speed and relay power current, so that the relay can normally turn on and off, and a 1N4007 diode is connected in parallel across the relay coil to provide a path for releasing reverse current for the relay inductor coil.

[0054] Another possible embodiment, the relay control module drives S8050 transistor through optocoupler PC817X1NSZ9F isolation, controls the start and stop of the relay, and realizes remote device switching.

[0055] Preferably, the power supply unit comprises a switching power supply, a fuse and a voltage-dependent resistor are arranged at the input end of the switching power supply, and the input end of the switching power supply is filtered by an inductor and a safety capacitor, a high-frequency and low-frequency filter capacitor is connected in parallel at the output end of the switching power supply, and a protection device is arranged. Specifically, the power supply unit selects a FA10-220S05E2 switching power supply, a 250V 2A fuse and a voltage-dependent resistor 10D561K are selected at the input end to prevent lightning and surge, a UU10.5 inductor (10mH) and a 1UF safety capacitor are used for power input filtering. A 1UF onyx capacitor and a 100UF high-frequency and low-resistance electrolytic capacitor are connected in parallel at the output end to eliminate high-frequency and low-frequency noise, and an SMBJ5.0A is selected to protect the output rear chip and other components.

[0056] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "exemplary embodiment", "preferred embodiment", "specific implementation", or "preferred implementation" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the exemplary description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0057] The above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can be modified, or some or all of the technical features can be replaced by equivalents; thus, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope defined by the claims of the present application.

Claims

1. A multi-channel data acquisition and wireless transmission control system, characterized by, The system comprises a main control unit, a signal amplification unit, a power management unit, a wireless communication unit, an analog-to-digital conversion unit, a relay control unit and a power supply unit. The power supply unit converts an external input power into a system working voltage. The power management unit is connected to the power supply unit and distributes the system working voltage into working power required by each functional unit. The main control unit is connected to the analog-to-digital conversion unit and the wireless communication unit. The signal amplification unit is connected between a sensor input end and the analog-to-digital conversion unit. The relay control unit is connected to the main control unit and is used to realize switch control of external equipment according to a control signal of the main control unit.

2. The multi-channel data acquisition and wireless transmission control system of claim 1, wherein, The main control unit adopts an ESP32-WROOM-32UE-N4 module, the main control unit is connected to the analog-to-digital conversion unit through an SPI interface and is connected to the wireless communication unit through a serial port.

3. The multi-channel data acquisition and wireless transmission control system of claim 1, wherein, The signal amplification unit comprises three AD620 instrument amplifiers, the input end of each AD620 instrument amplifier is connected in series with a resistor and connected in parallel with a capacitor to the ground, an RC filter circuit is formed, the feedback end of each AD620 instrument amplifier is connected to an adjustable potentiometer, and the output end of each AD620 instrument amplifier is connected in series with a current-limiting resistor.

4. The multi-channel data acquisition and wireless transmission control system of claim 3, wherein, The input end of the AD620 instrument amplifier is connected in series with a 10K resistor and connected in parallel with a 1uF capacitor, the feedback end of the AD620 instrument amplifier is connected to a 10KΩ potentiometer, and the output end of the AD620 instrument amplifier is connected in series with a 100Ω resistor.

5. The multi-channel data acquisition and wireless transmission control system of claim 1, wherein, The power management unit comprises: a 3.3V step-down circuit for supplying power to the main control unit and peripheral circuits, wherein the input of the 3.3V step-down circuit is connected to the output of the power supply unit; a 2.5V reference voltage circuit for generating a 2.5V reference voltage, wherein the input of the 2.5V reference voltage circuit is connected to the output of the power supply unit; a negative voltage generation circuit for providing a negative power supply for the signal amplification unit, wherein the input of the negative voltage generation circuit is connected to the output of the 2.5V reference voltage circuit and the output of the negative voltage generation circuit is connected to the signal amplification unit.

6. The multi-channel data acquisition and wireless transmission control system of claim 5, wherein, The 3.3V step-down circuit adopts a chip AMS1117-3.3, the 2.5V reference voltage circuit adopts a chip AMS1117-2.5, and the negative voltage generation circuit adopts an ICL7660 charge pump.

7. The multi-channel data acquisition and wireless transmission control system of claim 1, wherein, The wireless communication unit adopts an E70-433NW30S module, and each input and output pin is connected in series with a protection resistor.

8. The multi-channel data acquisition and wireless transmission control system of claim 1, wherein, The analog-to-digital conversion unit adopts a 24-bit ADS1220 chip, the digital supply voltage of which is 3.3V and the analog supply voltage of which is ±2.5V.

9. The multi-channel data acquisition and wireless transmission control system of claim 1, wherein, The relay control unit adopts an opto-coupler isolation drive circuit, a transistor drive circuit, a relay and a freewheeling protection circuit, wherein the opto-coupler isolation drive circuit is used to realize electrical isolation between the main control unit and the relay, the transistor drive circuit is used to amplify a control signal to drive the relay, the relay is used to control the power on-off of external equipment, and the freewheeling protection circuit is used to eliminate the reverse electromotive force of the relay coil; the opto-coupler isolation drive circuit adopts a PC817 opto-coupler, the transistor drive circuit adopts an S8050 transistor, and the freewheeling protection circuit adopts a 1N4007 diode connected in parallel across the relay coil.

10. The multi-channel data acquisition and wireless transmission control system of claim 5, wherein, The power supply unit includes a switching power supply, fuse and voltage-dependent resistor are arranged at the input of the switching power supply, and the input of the switching power supply is filtered by inductance and safety capacitor, high-frequency and low-frequency filter capacitors are connected in parallel at the output of the switching power supply, and the output of the switching power supply is connected with the input of 3.3V voltage reduction circuit and 2.5V reference voltage circuit respectively.

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