Conditioning circuit system based on UV detection signal

Abstract

The utility model discloses a conditioning circuit system based on UV detection signals. The conditioning circuit system comprises a U2 main chip, a UV transmitting tube driving circuit and a PD detection circuit. The UV-EN enable signal output end of the U2 main chip is in transmission connection with the input end of the UV transmitting tube driving circuit, and the detection end of the U2 main chip is in transmission connection with the output end of the PD detection circuit; a PD receiving tube in the PD detection circuit receives ultraviolet rays emitted by a UV transmitting tube in the UV transmitting tube driving circuit to generate current; a current conditioning circuit for conditioning current generated by a PD receiving tube is arranged between the output end of the PD detection circuit and the detection end of the U2 main chip; current signals generated by the PD receiving tube are subjected to signal conditioning such as current-voltage conversion, amplification, filtering and analog-to-digital conversion, digital signals are output, the signals are more stable and accurate, and capture of the signals by a chip is facilitated.

Description

Technical Field

[0001] This utility model relates to the field of circuit technology, and in particular to a conditioning circuit system based on UV detection signals. Background Technology

[0002] Current water quality testing methods mainly include measuring the total dissolved solids in water, chemical detection, and water quality sensor methods. When using UV ultraviolet light detection with water quality sensors, a more accurate detection signal is required. However, existing circuits for UV ultraviolet light detection of water quality do not perform precise processing on the detection signal. The values ​​obtained after signal processing are mixed with too many interference signals, resulting in inaccurate detection. The chip's capture and perception of the main signals is not obvious. Summary of the Invention

[0003] Purpose of the invention: In order to overcome the shortcomings of the existing technology, this utility model provides a conditioning circuit system based on UV detection signal. The system performs current-to-voltage conversion, amplification, filtering and analog-to-digital conversion on the current signal generated by the ultraviolet light emitted by the UV emitting tube and receives it using a PD receiving tube, and outputs a digital signal, making the signal more stable and accurate, and more conducive to the chip's signal capture.

[0004] Technical Solution: To achieve the above objectives, this utility model provides a conditioning circuit system based on UV detection signals, comprising a U2 main chip, a UV emitting tube driving circuit, and a PD detection circuit; the UV-EN enable signal output terminal of the U2 main chip is connected to the input terminal of the UV emitting tube driving circuit, and the detection terminal of the U2 main chip is connected to the output terminal of the PD detection circuit; the PD receiving tube in the PD detection circuit receives ultraviolet light emitted by the UV emitting tube in the UV emitting tube driving circuit to generate current; a current conditioning circuit for conditioning the current generated by the PD receiving tube is provided between the output terminal of the PD detection circuit and the detection terminal of the U2 main chip.

[0005] Furthermore, the current conditioning circuit includes an IV conversion circuit, an operational amplifier, a filter, and an ADC analog-to-digital converter; the negative input terminal of the IV conversion circuit is electrically connected to the output terminal of the PD detection circuit, and the IV conversion circuit, operational amplifier, filter, and ADC are connected in series; the output terminal of the ADC is electrically connected to the detection terminal of the U2 main chip.

[0006] Furthermore, the IV conversion circuit includes a MUX multiplexer and an amplifier; the negative input terminal of the amplifier is electrically connected to the output terminal of the PD detection circuit, and the output terminal of the amplifier is electrically connected to the output terminal of the MUX multiplexer; each of the multiple input terminals of the MUX multiplexer is electrically connected to the negative input terminal of the amplifier through a resistor.

[0007] Furthermore, the UV emitter driving circuit includes an IC21 integrated circuit, a UV emitter, an L21 inductor, and an R22 resistor; the SW terminal of the IC21 integrated circuit is electrically connected to one end of the L21 inductor, and one end of the L21 inductor is electrically connected to the BST terminal of the IC21 integrated circuit through a C23 capacitor; the other end of the L21 inductor is electrically connected to the positive terminal of the UV emitter, and the negative terminal of the UV emitter is electrically connected to the SEN terminal of the IC21 integrated circuit.

[0008] Furthermore, the EN terminal of IC21 is electrically connected to the UV-EN enable signal output terminal of the U2 main chip through resistor R22, and the EN terminal of IC21 is electrically connected to one end of resistor R23 through resistor R22, while the other end of resistor R23 is grounded.

[0009] Furthermore, the PD detection circuit includes a PD receiver tube and an IC41 integrated circuit; the IN_A+ terminal of the IC41 integrated circuit is electrically connected to the positive terminal of the PD receiver tube, the negative terminal of the PD receiver tube is electrically connected to the IN_A- terminal of the IC41 integrated circuit, and the negative terminal of the PD receiver tube is electrically connected to the OUTA terminal of the IC41 integrated circuit through a resistor R42, with a capacitor C42 connected in parallel with the resistor R42.

[0010] Furthermore, the OUTB terminal of the IC41 integrated circuit is electrically connected to one end of the R48 resistor, and the other end of the R48 resistor serves as the output terminal of the PD detection circuit; the other end of the R48 resistor is grounded through capacitors C45, C47, C48, and C49 respectively; the IN_B- terminal of the IC41 integrated circuit is grounded through resistor R47, and the OUTB terminal of the IC41 integrated circuit is electrically connected to the IN_B- terminal of the IC41 integrated circuit through resistor R46 and capacitor C46 respectively.

[0011] Beneficial Effects: This utility model discloses a conditioning circuit system based on UV detection signals. The IV conversion circuit has adjustable gain characteristics, which greatly increases the detection range and can broaden the application scenarios. It converts the current signal into a voltage signal, which is more conducive to subsequent signal processing. The voltage signal amplified by the operational amplifier makes the sensing signal easier for the chip to capture. The low-pass filter processes the signal and removes unnecessary interference signals introduced into the system. The intensity of the light emitted by the UV emitter can be changed to adapt to different environmental detection, making it more flexible and applicable in more environments. The current signal is conditioned by current-to-voltage conversion, amplification, filtering, and analog-to-digital conversion to output the values ​​of substances such as water quality, making the signal more stable and accurate, which is more conducive to the chip's signal capture. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of a conditioning circuit based on UV detection signals;

[0013] Figure 2 This is a circuit diagram of a UV emitter driver circuit.

[0014] Figure 3 This is the circuit diagram of the PD detection circuit;

[0015] Figure 4 This is a schematic diagram of the U2 main chip circuit. Detailed Implementation

[0016] The present invention will be further described below with reference to the accompanying drawings.

[0017] like Figure 1 As shown, a conditioning circuit system based on UV detection signals is characterized by comprising a U2 main chip 1, a UV emitting diode driving circuit 2, and a PD detection circuit 3. The UV-EN enable signal output terminal of the U2 main chip 1 is connected to the input terminal of the UV emitting diode driving circuit 2, and the detection terminal of the U2 main chip 1 is connected to the output terminal of the PD detection circuit 3. The PD receiving tube 32 in the PD detection circuit 3 receives ultraviolet light emitted by the UV emitting diode 22 in the UV emitting diode driving circuit 2 to generate current. A current conditioning circuit for conditioning the current generated by the PD receiving tube 32 is provided between the output terminal of the PD detection circuit 3 and the detection terminal of the U2 main chip 1. The current conditioning circuit performs current-to-voltage conversion, amplification, filtering, and analog-to-digital conversion on the current signal generated by the UV emitting diode 22 received by the PD receiving tube 32 to output a digital signal, which is more conducive to the chip's signal capture.

[0018] like Figure 1 As shown, the current conditioning circuit includes an IV conversion circuit 11, an operational amplifier 12, a filter 13, and an ADC analog-to-digital converter 14. The negative input terminal of the IV conversion circuit 11 is electrically connected to the output terminal of the PD detection circuit 3. The IV conversion circuit 11, operational amplifier 12, filter 13, and ADC analog-to-digital converter 14 are connected in series. The positive input terminal of the IV conversion circuit 11 is grounded, and the output terminal of the IV conversion circuit 11 is electrically connected to the input terminal of the operational amplifier 12. The output terminal of the operational amplifier 12 is electrically connected to the input terminal of the filter 13, the output terminal of the filter 13 is electrically connected to the input terminal of the ADC analog-to-digital converter 14, and the output terminal of the ADC analog-to-digital converter 14 is electrically connected to the detection terminal of the U2 main chip 1. The IV conversion circuit 11, operational amplifier 12, filter 13, and ADC analog-to-digital converter 14 are all powered by a voltage power supply.

[0019] like Figure 1As shown, the IV conversion circuit 11 includes a multi-function multiplexer (MUX) and an amplifier. The negative input terminal of the amplifier is electrically connected to the output terminal of the PD detection circuit 3, and the output terminal of the amplifier is electrically connected to the output terminal of the MUX. Each of the multiple input terminals of the MUX is electrically connected to the negative input terminal of the amplifier through a resistor. By selecting one of the multiple input terminals to be turned on through the MUX, the input to the IV conversion circuit 11 is amplified. By selecting different resistors connected to the negative input terminal and the output terminal of the amplifier, different gain effects can be selected to amplify the input signal. The IV conversion circuit 11 is a PGA adjustable gain amplifier that can convert the input current signal into a voltage signal. It has adjustable gain characteristics, which greatly increases the detection range and can broaden the application scenarios.

[0020] like Figure 2 As shown, the UV emitter driving circuit 2 includes an IC21 integrated circuit 21, a UV emitter 22, an L21 inductor 23, and an R22 resistor. The SW terminal of the IC21 integrated circuit 21 is electrically connected to one end of the L21 inductor 23, and one end of the L21 inductor 23 is electrically connected to the BST terminal of the IC21 integrated circuit 21 through a C23 capacitor. The other end of the L21 inductor 23 is electrically connected to the positive terminal of the UV emitter 22, and the negative terminal of the UV emitter 22 is electrically connected to the SEN terminal of the IC21 integrated circuit 21. The other end of the L21 inductor 23 is grounded through a C21 capacitor. The VIN terminal of the IC21 integrated circuit 21 is electrically connected to a voltage power supply, which outputs a 12V voltage and is grounded through a C22 capacitor. The VIN terminal of the IC21 integrated circuit 21 is electrically connected to the negative terminal of a D22 diode, and the positive terminal of the D22 diode is grounded. The SEN terminal of the IC21 integrated circuit 21 is grounded through a R21 resistor. UV emitters use single or combined devices with wavelengths of 245, 275, and 315 nm; they can be UVA, UVB, or UVC emitters; and the UVA, UVB, and UVC emitters are LEDs that emit ultraviolet light. The 275 nm wavelength UV emitter is mainly used for water quality detection.

[0021] The EN terminal of IC21 is electrically connected to the UV-EN enable signal output terminal of the U2 main chip 1 through resistor R22, and the EN terminal of IC21 is electrically connected to one end of resistor R23 through resistor R22, with the other end of resistor R23 grounded; the GND terminal of IC21 is grounded; the UV-EN enable signal output by the U2 main chip 1 controls the UV emitting tube 11 in the UV emitting tube drive circuit 3 to be energized and emit UV ultraviolet light.

[0022] like Figure 3As shown, the PD detection circuit 3 includes a PD receiver tube 32 and an IC41 integrated circuit 31. The IN_A+ terminal of the IC41 integrated circuit 31 is electrically connected to the positive terminal of the PD receiver tube 32, and the negative terminal of the PD receiver tube 32 is electrically connected to the IN_A- terminal of the IC41 integrated circuit 31. The negative terminal of the PD receiver tube 32 is electrically connected to the OUTA terminal of the IC41 integrated circuit 31 through a resistor R42, and a capacitor C42 is connected in parallel with the resistor R42. The OUTA terminal of the IC41 integrated circuit 31 is electrically connected to the IN-B+ terminal through a resistor R41, and the IN_A+ terminal of the IC41 integrated circuit 31 is grounded through a capacitor C43. The IN_A+ terminal of the IC41 integrated circuit 31 is electrically connected to one end of the resistor R43. The other end of the resistor R43 is electrically connected to a voltage power supply through the capacitor C41, and the other end of the resistor R43 is grounded. The PD receiver tube can be a device with a full-band photosensitive range covering UV A / B / C.

[0023] The OUTB terminal of IC41 integrated circuit 31 is electrically connected to one end of resistor R48, and the other end of resistor R48 serves as the output terminal of PD detection circuit 3. The other end of resistor R48 is grounded through capacitors C45, C47, C48, and C49. The IN_B- terminal of IC41 integrated circuit 31 is grounded through resistor R47, and the OUTB terminal of IC41 integrated circuit 31 is electrically connected to the IN_B- terminal of IC41 integrated circuit 31 through resistor R46 and capacitor C46. The V+ terminal of IC41 integrated circuit 31 is electrically connected to a voltage power supply, which outputs a voltage of 3.3V. The IN_B+ terminal of IC41 integrated circuit 31 is grounded through capacitor C44. A bias resistor is provided to make the single power supply output more stable. The capacitors perform simple filtering on the acquired signal to eliminate interference from other signals.

[0024] like Figure 4 As shown, the PA0 terminal of the U2 main chip 1 is electrically connected to one end of resistor R7, and one end of resistor R7 is grounded through capacitor C7; the other end of resistor R7 is electrically connected to the PC6 terminal of the U2 main chip 1 through resistor R5, and the other end of resistor R7 is electrically connected to the PC5 terminal of the U2 main chip 1 through resistor R6, and the other end of resistor R7 is electrically connected to a 3.3V power supply; the PA0 terminal of the U2 main chip 1 is electrically connected to one end of resistor R2, and one end of resistor R2 is grounded through capacitor C5; the other end of resistor R2 is grounded through resistor R1, and the other end of resistor R2 is electrically connected to pin 1 of CN4 / XHB-2A, pin 2 of CN4 / XHB-2A is electrically connected to a 3.3V power supply, and pin 2 of CN4 / XHB-2A is grounded through capacitor C1.

[0025] The VSS terminal of the U2 main chip 1 is grounded, and the VDD terminal of the U2 main chip 1 is electrically connected to a 3.3V power supply; the PB5 terminal of the U2 main chip 1 inputs the SWCLK signal, and the PD5 terminal of the U2 main chip 1 inputs the SWDIO signal; the PB4 terminal of the U2 main chip 1 outputs the UV-EN enable signal, the PD6 terminal of the U2 main chip 1 is the detection terminal, and the GND terminal of the U2 main chip 1 is grounded.

[0026] When testing water quality, the PD receiver and UV emitter are placed alternately in the same liquid. The system starts working after being powered on. The output terminal of the U2 main chip 1 outputs the UV-EN enable signal to control the UV emitter 22 of the UV emitter drive circuit 2 to emit UV ultraviolet light. The UV emitter 22 emits ultraviolet light with a wavelength range of 270~280nm into the liquid. The PD receiver collects the ultraviolet light that passes through the liquid. The PD receiver 32 of the PD detection circuit 3 transmits the UV ultraviolet light through the water or other media. The intensity of the ultraviolet light received by the PD receiver 32 generates a current. The generated current signal is based on the intensity or attenuation of the ultraviolet light received by the PD receiver 32.

[0027] The current generated by the PD receiver tube 32 is input to the IV conversion circuit 11. The IV conversion circuit 11 converts the input current signal into a voltage signal and the input current into a voltage signal. The operational amplifier 12 performs voltage-to-voltage amplification on the voltage signal again to obtain an amplified voltage signal, making the sensing signal easier for the chip to capture. The amplified signal is processed by a low-pass filter to remove unnecessary interference signals introduced into the system. The filtered voltage signal is converted into a digital signal by the ADC analog-to-digital converter and then input to the U2 main chip 1. The signal captured by the U2 main chip 1 is used to obtain a value that can be used to evaluate water quality. The value used to evaluate water quality is processed by a set algorithm to obtain water quality evaluation data, i.e., the water quality evaluation value. Alternatively, the value used to evaluate water quality can be analyzed by an external device to judge the quality of the liquid or to link with other systems.

[0028] For different liquids, the intensity of the light emitted by the UV emitting tube lamp can be adjusted, or the conversion coefficient of the primary current and voltage can be adjusted to adapt to different liquids in various environments. In addition, for the amplification circuit, the type of operational amplifier can be changed to achieve different amplification ratios and suitable bandwidths, making the system applicable in various environments and more flexible.

[0029] The above description is merely a preferred embodiment of the present utility model. Those skilled in the art can make several modifications and optimizations based on the above disclosure without departing from the basic principles described above. These modifications and optimizations should be considered as the scope of protection of the present utility model as understood.

Claims

1. A conditioning circuit system based on UV detection signals, characterized in that: It includes a U2 main chip (1), a UV emitting tube driving circuit (2), and a PD detection circuit (3); the UV-EN enable signal output terminal of the U2 main chip (1) is connected to the input terminal of the UV emitting tube driving circuit (2), and the detection terminal of the U2 main chip (1) is connected to the output terminal of the PD detection circuit (3); the PD receiving tube (32) in the PD detection circuit (3) receives the ultraviolet light emitted by the UV emitting tube (22) in the UV emitting tube driving circuit (2) to generate current; a current conditioning circuit for conditioning the current generated by the PD receiving tube (32) is set between the output terminal of the PD detection circuit (3) and the detection terminal of the U2 main chip (1).

2. The conditioning circuit system based on UV detection signal according to claim 1, characterized in that: The current conditioning circuit includes an IV conversion circuit (11), an operational amplifier (12), a filter (13), and an ADC analog-to-digital converter (14); the negative input terminal of the IV conversion circuit (11) is electrically connected to the output terminal of the PD detection circuit (3), and the IV conversion circuit (11), operational amplifier (12), filter (13), and ADC analog-to-digital converter (14) are connected in series; the output terminal of the ADC analog-to-digital converter (14) is electrically connected to the detection terminal of the U2 main chip (1).

3. The conditioning circuit system based on UV detection signal according to claim 2, characterized in that: The IV conversion circuit (11) includes a MUX multiplexer and an amplifier; the negative input terminal of the amplifier is electrically connected to the output terminal of the PD detection circuit (3), and the output terminal of the amplifier is electrically connected to the output terminal of the MUX multiplexer; each of the multiple input terminals of the MUX multiplexer is electrically connected to the negative input terminal of the amplifier through a resistor.

4. The conditioning circuit system based on UV detection signal according to claim 1, characterized in that: The UV emitting tube driving circuit (2) includes an IC21 integrated circuit (21), a UV emitting tube (22), an L21 inductor (23), and an R22 resistor; the SW terminal of the IC21 integrated circuit (21) is electrically connected to one end of the L21 inductor (23), and one end of the L21 inductor (23) is electrically connected to the BST terminal of the IC21 integrated circuit (21) through a C23 capacitor; the other end of the L21 inductor (23) is electrically connected to the positive terminal of the UV emitting tube (22), and the negative terminal of the UV emitting tube (22) is electrically connected to the SEN terminal of the IC21 integrated circuit (21).

5. The conditioning circuit system based on UV detection signal according to claim 4, characterized in that: The EN terminal of IC21 integrated circuit (21) is electrically connected to the UV-EN enable signal output terminal of U2 main chip (1) through resistor R22, and the EN terminal of IC21 integrated circuit (21) is electrically connected to one end of resistor R23 through resistor R22, and the other end of resistor R23 is grounded.

6. The conditioning circuit system based on UV detection signal according to claim 1, characterized in that: The PD detection circuit (3) includes a PD receiver tube (32) and an IC41 integrated circuit (31); the IN_A+ terminal of the IC41 integrated circuit (31) is electrically connected to the positive terminal of the PD receiver tube (32), the negative terminal of the PD receiver tube (32) is electrically connected to the IN_A- terminal of the IC41 integrated circuit (31), and the negative terminal of the PD receiver tube (32) is electrically connected to the OUTA terminal of the IC41 integrated circuit (31) through a resistor R42, and a capacitor C42 is connected in parallel with the resistor R42.

7. A conditioning circuit system based on a UV detection signal according to claim 6, characterized in that: The OUTB terminal of the IC41 integrated circuit (31) is electrically connected to one end of the R48 resistor, and the other end of the R48 resistor serves as the output terminal of the PD detection circuit (3). The other end of the R48 resistor is grounded through capacitors C45, C47, C48 and C49 respectively. The IN_B- terminal of the IC41 integrated circuit (31) is grounded through resistor R47, and the OUTB terminal of the IC41 integrated circuit (31) is electrically connected to the IN_B- terminal of the IC41 integrated circuit (31) through resistor R46 and capacitor C46 respectively.

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