Hydrogen detection circuit

Abstract

The utility model discloses a hydrogen detection circuit which comprises a single-chip microcomputer MCU, and the single-chip microcomputer MCU is respectively connected with a thermal conductivity temperature compensation circuit, a semiconductor temperature compensation circuit, a control execution module, a digital display module, an isolation communication module, an RTC circuit module, a constant source flow module and a double-path high-precision acquisition chip. Wherein the double-path high-precision acquisition chip is respectively connected with the thermal conductivity type hydrogen sensor and the semiconductor hydrogen sensor, the thermal conductivity type hydrogen sensor and the semiconductor hydrogen sensor are connected with the constant source flow module, and meanwhile, the thermal conductivity temperature compensation circuit is connected with the thermal conductivity type hydrogen sensor. And the semiconductor temperature compensation circuit is connected with the semiconductor hydrogen sensor. The hydrogen sensor has the beneficial effects that the detection range from several PPM to tens of thousands of PPM is realized, the RTC circuit in the circuit can compensate attenuation of the life cycle of the whole hydrogen sensor, and the detection precision is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to hydrogen detection field, concretely, relate to a hydrogen detection circuit. BACKGROUND

[0002] Hydrogen is a flammable and explosive gas, which has great harm to human body and environment. Therefore, the detection of hydrogen is of great significance. The existing detection circuit mostly relies on hydrogen concentration sensor for detection, however, in the use process of single sensor, if a hydrogen concentration sensor with a large range of resistance value change is used, the measurement range is widened, and high concentration can be measured. However, the measurement accuracy is reduced in the low concentration area. On the other hand, if a hydrogen concentration sensor with a small range of resistance value change is used, high-precision measurement can be performed in the low concentration area. However, because the measurement range is small, high concentration cannot be measured.

[0003] Therefore, there is a lack of a hydrogen detection circuit that can detect not only high concentration but also low concentration.

[0004] At present, no effective solution has been proposed for the problems in the related art. CONTENT OF THE UTILITY MODEL

[0005] The utility model aims at providing a hydrogen detection circuit to solve the problems in the background art.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical scheme:

[0007] A hydrogen detection circuit, comprising a single-chip microcomputer MCU, the single-chip microcomputer MCU is connected with a thermal conductivity temperature compensation circuit, a semiconductor temperature compensation circuit, a control execution module, a digital display module, an isolation communication module, an RTC circuit module, a constant source flow module and a double-path high-precision acquisition chip respectively;

[0008] The double-path high-precision acquisition chip is connected with a thermal conductivity hydrogen sensor and a semiconductor hydrogen sensor respectively, and the thermal conductivity hydrogen sensor and the semiconductor hydrogen sensor are connected with the constant source flow module, at the same time, the thermal conductivity temperature compensation circuit is connected with the thermal conductivity hydrogen sensor, and the semiconductor temperature compensation circuit is connected with the semiconductor hydrogen sensor.

[0009] Further, in order to ensure that information can be grasped by relevant personnel in the background in time, the isolation communication module is connected with an upper computer, and the isolation communication module is a CAN / 485 isolation communication circuit.

[0010] Further, in order to ensure more accurate heat dissipation and provide indication information for relevant personnel, the control execution module is connected with a cooling fan and an indicator light.

[0011] Further, in order to use high-precision low-consumption chip, the double high-precision acquisition chip is CS1180 analog-digital conversion chip.

[0012] Further, the thermal conductive temperature compensation circuit comprises a U3A operational amplifier, the IN- end of the U3A operational amplifier is connected with a resistor R10 in series, the resistor R10 is connected with a resistor R14 in series, the resistor R14 is connected with the ground in series, the IN+ end of the U3A operational amplifier is connected with a resistor R19 in series, the resistor R19 is connected with the OUT7 end of a U3B operational amplifier in series, the IN- end of the U8B operational amplifier is connected with the line of the resistor R19 connected with the OUT7 end of the U3B operational amplifier in series, the VCC end of the U3A operational amplifier is connected with a VCC5VA power supply and a capacitor C9 in series respectively, the capacitor C9 is connected with the ground in series, the -VCC end of the U3A operational amplifier is connected with the ground in series, the OUT1 end of the U3A operational amplifier is connected with a resistor R13 in series, the line of the OUT1 end of the U3A operational amplifier connected with the resistor R13 and the line of the IN- end of the U3A operational amplifier connected with the resistor R10 are connected with a capacitor C8 in parallel, the capacitor C8 is connected with a resistor R6 in parallel at both ends, the resistor R13 is connected with the port 1 of a triode L8550QLT1G in series, the port 2 of the triode L8550QLT1G is connected with the VCC5VA power supply in series, the port 3 of the triode L8550QLT1G is connected with a resistor R16 in series, the line of the port 3 of the triode L8550QLT1G connected with the resistor R16 and the line of the resistor R10 connected with the resistor R14 are connected with a resistor R7 in parallel, the resistor R16 is connected with the pin 1 of a chip J2 in series, the line of the resistor R16 connected with the pin 1 of the chip J2 and the IN+ end of the U3B operational amplifier are connected in electricity, the pin 2 and the pin 4 of the chip J2 are connected with the ground in series.

[0013] Further, the semiconductor temperature compensation circuit comprises a U8A operational amplifier, the IN- end of the U8A operational amplifier is connected with a resistor R24 in series, the resistor R24 is connected with the ground in series, the IN+ end of the U8A operational amplifier is connected with a resistor R28 in series, the resistor R28 is connected with a VREF_1.35V power supply in series, the line of the IN+ end of the U8A operational amplifier connected with the resistor R28 is connected with a resistor R29 in electricity, the resistor R29 is connected with the OUT7 end of a U8B operational amplifier in series, the IN- end of the U8B operational amplifier is connected with the line of the resistor R29 connected with the OUT7 end of the U8B operational amplifier in electricity, the VCC end of the U8A operational amplifier is connected with a VCC5VA and a capacitor C16 in series respectively, the capacitor C16 is connected with the ground in series, the -VCC end of the U8A operational amplifier is connected with the ground in series, the OUT1 end of the U8A operational amplifier is connected with a resistor R25 in series, the line of the OUT1 end of the U8A operational amplifier connected with the resistor R25 and the line of the IN- end of the U8A operational amplifier connected with the resistor R24 are connected with a resistor R22 in parallel, the resistor R25 is connected with the port 1 of a chip J3 in series, the line of the resistor R25 connected with the port 1 of the chip J3 is connected with a DC3.3VA power supply and the IN+ end of the U8B operational amplifier in electricity respectively, the port 2 and the port 4 of the chip J3 are connected with the ground in series respectively.

[0014] Compared with the prior art, the hydrogen detection circuit has the following beneficial effects:

[0015] By using the semiconductor hydrogen detection sensor and the thermal conductivity hydrogen sensor in combination, a detection range of several PPM to tens of thousands of PPM is realized, the RTC circuit in the circuit can compensate the attenuation of the life cycle of the entire hydrogen sensor, the detection precision is improved, the constant-current high-precision detection circuit can adjust and compensate the temperature of the semiconductor and the thermal conductivity material, the collection precision of the hydrogen concentration is further improved, the communication, digital display and execution mechanism are added in the circuit, unattended and data uploading are facilitated, and the practicability is improved. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical scheme in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0017] Figure 1 is a structure diagram of a hydrogen detection circuit according to an embodiment of the present application;

[0018] Figure 2 is a structure diagram of a hydrogen detection circuit according to an embodiment of the present application;

[0019] Figure 3 is a structure diagram of a hydrogen detection circuit according to an embodiment of the present application.

[0020] Reference signs:

[0021] 1, single-chip microcomputer MCU; 2, thermal conductivity temperature compensation circuit; 3, semiconductor temperature compensation circuit; 4, control execution module; 5, digital display module; 6, isolation communication module; 7, RTC circuit module; 8, constant source current module; 9, double-path high-precision acquisition chip; 10, thermal conductivity hydrogen sensor; 11, semiconductor hydrogen sensor; 12, host computer. DETAILED DESCRIPTION

[0022] In the following, the utility model will be further described in combination with the drawings and the specific embodiments:

[0023] Please refer to Figure 1 , according to the structure diagram of a hydrogen detection circuit according to an embodiment of the present application, as shown in the accompanying Figures 1-3As shown, it comprises a single-chip microcomputer MCU1, a thermal conductivity temperature compensation circuit 2, a semiconductor temperature compensation circuit 3, a control execution module 4, a digital display module 5, an isolation communication module 6, an RTC circuit module 7, a constant current source module 8 and a double-path high-precision acquisition chip 9 are connected to the single-chip microcomputer MCU1 respectively; wherein, a thermal conductivity hydrogen sensor 10 and a semiconductor hydrogen sensor 11 are connected to the double-path high-precision acquisition chip 9 respectively, the thermal conductivity hydrogen sensor 10 and the semiconductor hydrogen sensor 11 are connected with the constant current source module 8, at the same time, the thermal conductivity temperature compensation circuit 2 is connected with the thermal conductivity hydrogen sensor 10, and the semiconductor temperature compensation circuit 3 is connected with the semiconductor hydrogen sensor 11. The isolation communication module 6 is connected with an upper computer 12, and the isolation communication module 6 is a CAN / 485 isolation communication circuit. The control execution module 4 is connected with a cooling fan and an indicator light. The double-path high-precision acquisition chip 9 is a CS1180 analog-digital conversion chip.

[0024] Through the above scheme of the utility model, the thermal conductivity hydrogen sensor 10 can detect the value of high concentration interval hydrogen; the semiconductor hydrogen sensor 11 can detect the value of low concentration interval hydrogen, the double-path high-precision acquisition chip 9 is used for collecting the analog voltage of thermal conductivity and semiconductor, and is transmitted to the single-chip microcomputer MCU1 through SPI communication, the thermal conductivity temperature compensation circuit 2 is used for compensating the temperature change of the thermal conductivity sensor when being heated and being affected by the change of external environment temperature;

[0025] The semiconductor temperature compensation circuit 3 compensates the temperature change of the semiconductor sensor when being heated and being affected by the change of external environment temperature;

[0026] The control execution module 4 controls the load end when needing to realize action or control the relay fan or the indicator light and other mechanisms;

[0027] The digital display module 5 displays the current acquisition information and running state information;

[0028] The isolation communication module 6 is a CAN / 485 isolation communication used for communicating with external equipment or setting internal parameters and the like;

[0029] The upper computer 12 is used for displaying the current hydrogen concentration range, running working state, communication data and the like;

[0030] The RTC circuit module 7 is used for compensating the attenuation of the semiconductor in the whole life cycle;

[0031] The constant current source module 8 provides constant heating current for the thermal conductivity and the semiconductor, because the impedance of the material is changed in the process of heating, the constant current is provided to maintain the stability of the temperature.

[0032] The thermal conduction temperature compensation circuit 2 comprises a U3A operational amplifier, the IN- end of the U3A operational amplifier is connected with a resistor R10 in series, the resistor R10 is connected with a resistor R14 in series, the resistor R14 is connected with the ground in series, the IN+ end of the U3A operational amplifier is connected with a resistor R19 in series, the resistor R19 is connected with the OUT7 end of a U3B operational amplifier in series, the IN- end of the U8B operational amplifier is connected with the line of the resistor R19 connected with the OUT7 end of the U3B operational amplifier in series, the VCC end of the U3A operational amplifier is connected with a VCC5VA power supply and a capacitor C9 in series respectively, the capacitor C9 is connected with the ground in series, the -VCC end of the U3A operational amplifier is connected with the ground in series, the OUT1 end of the U3A operational amplifier is connected with a resistor R13 in series, the line of the OUT1 end of the U3A operational amplifier connected with the resistor R13 and the line of the IN- end of the U3A operational amplifier connected with the resistor R10 are connected with a capacitor C8 in parallel, the capacitor C8 is connected with a resistor R6 in parallel at both ends, the resistor R13 is connected with the port 1 of a triode L8550QLT1G in series, the port 2 of the triode L8550QLT1G is connected with the VCC5VA power supply in series, the port 3 of the triode L8550QLT1G is connected with a resistor R16 in series, the line of the port 3 of the triode L8550QLT1G connected with the resistor R16 and the line of the resistor R10 connected with the resistor R14 are connected with a resistor R7 in parallel, the resistor R16 is connected with the pin 1 of a chip J2 in series, the line of the resistor R16 connected with the pin 1 of the chip J2 and the IN+ end of the U3B operational amplifier are connected in an electrical manner, the pin 2 and the pin 4 of the chip J2 are connected with the ground in series.

[0033] The semiconductor temperature compensation circuit 3 comprises a U8A operational amplifier, the IN- end of the U8A operational amplifier is connected with a resistor R24 in series, the resistor R24 is connected with the ground in series, the IN+ end of the U8A operational amplifier is connected with a resistor R28 in series, the resistor R28 is connected with a VREF_1.35V power supply in series, the line of the IN+ end of the U8A operational amplifier connected with the resistor R28 is connected with a resistor R29 in an electrical manner, the resistor R29 is connected with the OUT7 end of a U8B operational amplifier in series, the IN- end of the U8B operational amplifier is connected with the line of the resistor R29 connected with the OUT7 end of the U8B operational amplifier in an electrical manner, the VCC end of the U8A operational amplifier is connected with a VCC5VA and a capacitor C16 in series respectively, the capacitor C16 is connected with the ground in series, the -VCC end of the U8A operational amplifier is connected with the ground in series, the OUT1 end of the U8A operational amplifier is connected with a resistor R25 in series, the line of the OUT1 end of the U8A operational amplifier connected with the resistor R25 and the line of the IN- end of the U8A operational amplifier connected with the resistor R24 are connected with a resistor R22 in parallel, the resistor R25 is connected with the port 1 of a chip J3 in series, the line of the resistor R25 connected with the port 1 of the chip J3 is connected with a DC3.3VA power supply and the IN+ end of the U8B operational amplifier in an electrical manner respectively, the port 2 and the port 4 of the chip J3 are connected with the ground in series.

[0034] In order to facilitate the understanding of the above technical scheme of the utility model, the working principle or operation mode of the utility model in the actual process is explained in detail.

[0035] In practical application, when hydrogen enters the semiconductor hydrogen sensor 11 and the thermal conductivity type hydrogen sensor 10, the sensor will generate a corresponding voltage change signal, and there are several PPM to several hundred PPM of hydrogen in the air. Through the high-precision dual-channel high-precision acquisition chip 9, the voltage of the weak signal is collected, and the collected voltage parameters are transmitted to the single-chip microcomputer MCU1 through SPI communication. The single-chip microcomputer MCU1 controls the corresponding execution unit through the control execution module 4 according to the application requirement, and transmits the collected parameters to the upper computer 12 or other communication equipment through communication. Due to the special characteristics of the semiconductor hydrogen sensor 11, the low-concentration hydrogen value is detected, and with the increase of the hydrogen concentration, the hydrogen concentration is detected by the thermal conductivity type hydrogen sensor 10. Through the two types of hydrogen sensor materials, hydrogen concentrations from several PPM to tens of thousands of PPM can be detected. With the consumption of these two types of materials, the life cycle is continuously attenuated, and the RTC circuit module 7 compensates for the attenuation of the life cycle of the entire hydrogen sensor according to the change of the electric signal. According to the special characteristics of the thermal conductivity and semiconductor materials, the impedance of the materials will change during the heating process of the two types of materials. In order to maintain a constant temperature, constant current heating is performed on the two types of materials, and different temperature compensation is performed on the two types of materials.

[0036] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A hydrogen detection circuit, characterized by, It includes single-chip microcomputer MCU (1), the single-chip microcomputer MCU (1) is connected with thermal conductivity temperature compensation circuit (2), semiconductor temperature compensation circuit (3), control execution module (4), digital display module (5), isolation communication module (6), RTC circuit module (7), constant source flow module (8) and double-path high-precision acquisition chip (9) respectively, Wherein, the double-path high-precision acquisition chip (9) is connected with thermal conductivity hydrogen sensor (10) and semiconductor hydrogen sensor (11) respectively, the thermal conductivity hydrogen sensor (10) and the semiconductor hydrogen sensor (11) are connected with the constant source flow module (8), meanwhile, the thermal conductivity temperature compensation circuit (2) is connected with the thermal conductivity hydrogen sensor (10), and the semiconductor temperature compensation circuit (3) is connected with the semiconductor hydrogen sensor (11).

2. The hydrogen detection circuit of claim 1, wherein, The isolation communication module (6) is connected with host computer (12), and the isolation communication module (6) is CAN / 485 isolation communication circuit.

3. The hydrogen detection circuit of claim 1, wherein, The control execution module (4) is connected with cooling fan and indicator light.

4. The hydrogen detection circuit of claim 1, wherein, The double-path high-precision acquisition chip (9) is ADS118 analog-digital conversion chip.

5. The hydrogen detection circuit of claim 1, wherein, The thermal conductivity temperature compensation circuit (2) includes U3A operational amplifier, the U3A operational amplifier IN- end is connected with resistance R10 in series, the resistance R10 is connected with resistance R14 in series, the resistance R14 is connected with ground in series, the U3A operational amplifier IN+ end is connected with resistance R19 in series, the resistance R19 is connected with U3B operational amplifier OUT7 end in series, the U3B operational amplifier IN- end and the line of U3B operational amplifier OUT7 end are electrically connected, the U3A operational amplifier VCC end is electrically connected with VCC5VA power supply and capacitor C9 respectively, the capacitor C9 is connected with ground in series, the U3A operational amplifier-VCC end is connected with ground in series, the U3A operational amplifier OUT1 end is connected with resistance R13 in series, the line of U3A operational amplifier OUT1 end connected with resistance R13 and the line of U3A operational amplifier IN- end connected with resistance R10 are connected with capacitor C8 in parallel, the capacitor C8 is connected with resistance R6 in parallel at both ends, the resistance R13 is connected with the port 1 of triode L8550QLT1G in series, the port 2 of triode L8550QLT1G is connected with VCC5VA power supply in series, the port 3 of triode L8550QLT1G is connected with resistance R16 in series, the line of port 3 of triode L8550QLT1G connected with resistance R16 and the line of resistance R10 connected with resistance R14 are connected with resistance R7 in parallel, the resistance R16 is connected with the pin 1 of chip J2 in series, the line of resistance R16 connected with the pin 1 of chip J2 and U3B operational amplifier IN+ end are electrically connected, the pin 2 and pin 4 of chip J2 are connected with ground in series.

6. The hydrogen detection circuit of claim 1, wherein, The semiconductor temperature compensation circuit (3) includes U8A operational amplifier, the U8A operational amplifier IN- end series resistance R24, the resistance R24 is connected in series with the ground, the U8A operational amplifier IN+ end series resistance R28, the resistance R28 is connected in series with VREF_1.35V power supply, the U8A operational amplifier IN+ end series resistance R28 line is electrically connected with resistance R29, the resistance R29 is connected in series with U8B operational amplifier OUT7 end, the U8B operational amplifier IN- end is electrically connected with the line of U8B operational amplifier OUT7 end series resistance R29, the U8A operational amplifier VCC end is connected in series with VCC5VA and capacitor C16 respectively, the capacitor C16 is connected in series with the ground, the U8A operational amplifier VCC- end is connected in series with the ground, the U8A operational amplifier OUT1 end series resistance R25, the line of U8A operational amplifier OUT1 end series resistance R25 and the line of U8A operational amplifier IN- end series resistance R24 are connected with resistance R22 in parallel, the resistance R25 is connected in series with chip J3 port 1, the line of resistance R25 connected in series with chip J3 port 1 is electrically connected with DC3.3VA power supply and U8B operational amplifier IN+ end respectively, the chip J3 port 2 and 4 are connected in series with the ground respectively.

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