Remote wireless environment monitoring control unit

Abstract

The utility model relates to the technical field of temperature monitoring, in particular to a remote wireless environment monitoring control unit, which comprises a constant current source circuit, a temperature sampling resistor J2, an instrument operational amplifier circuit and a hysteresis comparison circuit. The constant current source circuit comprises a reference source U1, a four-channel operational amplifier U2A, a four-channel operational amplifier U2B, resistors R1, R2, R3, R4, R5, R6 and R7, capacitors C1, C2, C3, C4, C5, C6 and C10 and a fuse F1; the instrument operational amplifier circuit comprises an instrument amplifier U5 and a resistor R13; the hysteresis comparison circuit comprises a four-channel operational amplifier U2C, a four-channel operational amplifier U2D, a resistor R8, a resistor R9, a resistor R10 and a resistor R12. According to the utility model, the constant current source circuit is arranged to provide voltage with extremely high precision and output constant current, and the hysteresis comparison circuit is arranged to effectively prevent the problem of extremely unstable output caused by the fact that an output point and a comparison point are always compared.

Description

Technical Field

[0001] The utility model relates to the technical field of temperature monitoring, and particularly relates to a remote wireless environment monitoring and control unit. Background Art

[0002] During the operation of electrical equipment, a large amount of heat is generated inside. These heats need to be monitored in real time to effectively control the internal temperature. Therefore, general electrical equipment needs to be provided with an internal environment temperature monitoring unit. However, the existing internal environment temperature monitoring unit of electrical equipment generally realizes it by setting a temperature acquisition resistor and its corresponding control circuit. During this process, signals and comparison signals are output in real time. But there is a problem with the current such design, that is, the output point and the comparison point are always in a comparison state, which will cause the output to be extremely unstable. In view of this, we propose a remote wireless environment monitoring and control unit. Content of the Utility Model

[0003] The main purpose of the utility model is to provide a remote wireless environment monitoring and control unit, including a constant current source circuit, a temperature sampling resistor J2, an instrumentation operational amplifier circuit, and a hysteresis comparison circuit;

[0004] The constant current source circuit includes a reference source U1, a four-channel operational amplifier U2A, a four-channel operational amplifier U2B, resistors R1, R2, R3, R4, R5, R6, R7, capacitors C1, C2, C3, C4, C5, C6, C10, and a fuse F1;

[0005] The instrumentation operational amplifier circuit includes an instrumentation amplifier U5 and a resistor R13;

[0006] The hysteresis comparison circuit includes a four-channel operational amplifier U2C, a four-channel operational amplifier U2D, resistors R8, R9, R10, and R12.

[0007] Preferably, the capacitor C1 is connected to the pin 1 of the reference source U1, the capacitors C4 and the resistor R5 are connected in parallel and then connected to the pins 2 and 3 of the reference source U1, the resistor R2 is connected between the reference source U1 and the four-channel operational amplifier U2B, and the capacitors C5, the resistors R6 and R7 are connected in series and then connected between the pin 5 and the pin 7 of the four-channel operational amplifier U2B.

[0008] Preferably, the resistor R1 is connected between the pin 1 of the four-channel operational amplifier U2A and the pin 5 of the four-channel operational amplifier U2B, the resistors R3 and R4 are connected in series and then connected between the pin 3 of the four-channel operational amplifier U2A and the pin 7 of the four-channel operational amplifier U2B, the capacitors C2 and C3 are connected in parallel and one end is connected to the pin 4 of the four-channel operational amplifier U2A, and the other end is grounded. The capacitors C6 and C10 are connected in parallel and one end is connected to the IN1- end of the four-channel operational amplifier U2A, and the other end is grounded.

[0009] Preferably, the fuse F1 is connected between pin 3 of the four-channel operational amplifier U2A and the temperature sampling resistor J2.

[0010] Preferably, both ends of the resistor R13 are connected between pin 1 and pin 8 of the instrumentation amplifier U5, pin 1 of the temperature sampling resistor J2 is connected to pin 2 of the instrumentation amplifier U5, pin 2 of the temperature sampling resistor J2 is connected to pin 3 of the instrumentation amplifier U5, and pin 5 of the instrumentation amplifier U5 is grounded.

[0011] Preferably, pin 10 of the four-channel operational amplifier U2C and pin 13 of the four-channel operational amplifier U2D are both connected to pin 6 of the instrumentation amplifier U5, and the resistor R8 is connected between pin 10 of the four-channel operational amplifier U2C and pin 6 of the instrumentation amplifier U5, and the resistor R10 is connected between pin 13 of the four-channel operational amplifier U2D and pin 6 of the instrumentation amplifier U5.

[0012] Preferably, the resistor R9 is connected between pin 9 and pin 8 of the four-channel operational amplifier U2C, and the resistor R10 is connected between pin 14 and pin 13 of the four-channel operational amplifier U2D.

[0013] Compared with the prior art, the present utility model has the following beneficial effects:

[0014] By providing a constant current source circuit, the present utility model can provide a voltage with extremely high precision and output a constant current. By providing a hysteresis comparison circuit, the problem that the output point and the comparison point keep comparing all the time, resulting in extremely unstable output, can be effectively prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall circuit of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0016] In order to further elaborate on the technical means and effects adopted by the present utility model to achieve the predetermined utility model purpose, the following, in conjunction with the drawings and preferred embodiments, will describe in detail the specific implementation manners, structures, features and their effects according to the present utility model.

[0017] Please refer to Figure 1 , this embodiment provides a remote wireless environmental monitoring and control unit, including a constant current source circuit, a temperature sampling resistor J2, an instrumentation amplifier circuit, and a hysteresis comparison circuit;

[0018] The constant current source circuit includes a reference source U1, a four-channel operational amplifier U2A, a four-channel operational amplifier U2B, resistors R1, R2, R3, R4, R5, R6, R7, capacitors C1, C2, C3, C4, C5, C6, C10, and a fuse F1;

[0019] The instrumentation operational amplifier circuit includes an instrumentation amplifier U5 and a resistor R13;

[0020] The hysteresis comparison circuit includes a four-channel operational amplifier U2C, a four-channel operational amplifier U2D, and resistors R8, R9, R10, and R12.

[0021] Preferably, a capacitor C1 is connected to pin 1 of the reference source U1, a capacitor C4 and a resistor R5 are connected in parallel and then connected to pins 2 and 3 of the reference source U1, a resistor R2 is connected between the reference source U1 and the four-channel operational amplifier U2B, and a capacitor C5, resistors R6 and R7 are connected in series and then connected between pin 5 and pin 7 of the four-channel operational amplifier U2B.

[0022] Preferably, a resistor R1 is connected between pin 1 of the four-channel operational amplifier U2A and pin 5 of the four-channel operational amplifier U2B, resistors R3 and R4 are connected in series and then connected between pin 3 of the four-channel operational amplifier U2A and pin 7 of the four-channel operational amplifier U2B, a capacitor C2 and a capacitor C3 are connected in parallel and one end is connected to pin 4 of the four-channel operational amplifier U2A and the other end is grounded, and a capacitor C6 and a capacitor C10 are connected in parallel and one end is connected to the IN1- terminal of the four-channel operational amplifier U2A and the other end is grounded.

[0023] Preferably, a fuse F1 is connected between pin 3 of the four-channel operational amplifier U2A and the temperature sampling resistor J2.

[0024] Preferably, both ends of the resistor R13 are respectively connected between pin 1 and pin 8 of the instrumentation amplifier U5, pin 1 of the temperature sampling resistor J2 is connected to pin 2 of the instrumentation amplifier U5, pin 2 of the temperature sampling resistor J2 is connected to pin 3 of the instrumentation amplifier U5, and pin 5 of the instrumentation amplifier U5 is grounded.

[0025] Preferably, pin 10 of the four-channel operational amplifier U2C and pin 13 of the four-channel operational amplifier U2D are both connected to pin 6 of the instrumentation amplifier U5, and the resistor R8 is connected between pin 10 of the four-channel operational amplifier U2C and pin 6 of the instrumentation amplifier U5, and the resistor R10 is connected between pin 13 of the four-channel operational amplifier U2D and pin 6 of the instrumentation amplifier U5.

[0026] Preferably, the resistor R9 is connected between pin 9 and pin 8 of the four-channel operational amplifier U2C, and the resistor R10 is connected between pin 14 and pin 13 of the four-channel operational amplifier U2D.

[0027] Utilize the characteristics of the temperature sampling resistor J2 with a negative temperature coefficient resistor and a constant current source, and collect the voltage through an instrumentation amplifier, and feedback the temperature change through this voltage;

[0028] The purpose of the constant current source circuit is to generate constant current. Its principle is to use operational amplifiers and peripheral resistors to make the voltage difference between pin 7 and pin 3 of the four-channel operational amplifiers U2A and U2B the reference source output voltage, and then add corresponding resistors (R3+R4) between pin 7 and pin 3 to finally output a constant current. The final output current is 4.096V / 4.096K, generating a current of 1mA.

[0029] Among them, U1 is the reference source, which can provide extremely high-precision voltage, such as 4.096V in the figure. The capacitors C1 and C4 connected to the reference source U1 are used to filter out noise. R5 is to make the output voltage more stable. The resistors R6 and R7 are matched so that the voltage at pin 7 of the four-channel operational amplifier U2B = 2*pin 5 voltage, and the resistors R1 and R2 are matched so that the voltage at pin 1 of the four-channel operational amplifier U2A = 2*pin 5 voltage, and the voltage at pin 3 = pin 1 voltage, the voltage at pin 7 - the voltage at pin 3 = 4.096V, (R3+R4) = 4.096K, and the final calculation shows that the current is 1mA.

[0030] The instrument amplifier U5 collects the voltage across the temperature sampling resistor J2, where R13 can be used to adjust the amplification factor, G = 1 + 50 / R13, where the temperature sampling resistor J2 is a negative temperature coefficient resistor, and as the temperature increases, the resistance decreases;

[0031] The hysteresis comparator circuit is set to prevent the anti-ringing effect caused by the output point and the comparison point being compared all the time, resulting in extremely unstable output. The two REF reference points can be set by the user to set the temperature range. R8 and R10 are used to isolate the voltage to prevent the two comparison points from affecting each other. R9 and R12 are used to generate a hysteresis comparator. A certain threshold voltage is formed through R9 and R12. When the input voltage is greater than / less than a certain range of the comparison point, the output can change.

[0032] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A remote wireless environmental monitoring and control unit, characterized in that, It includes a constant current source circuit, a temperature sampling resistor J2, an instrumentation amplifier circuit, and a hysteresis comparison circuit; The constant current source circuit includes a reference source U1, a four-channel operational amplifier U2A, a four-channel operational amplifier U2B, resistors R1, R2, R3, R4, R5, R6, R7, capacitors C1, C2, C3, C4, C5, C6, C10, and a fuse F1; The instrumentation amplifier circuit includes an instrumentation amplifier U5 and a resistor R13; The hysteresis comparison circuit includes a four-channel operational amplifier U2C, a four-channel operational amplifier U2D, resistors R8, R9, R10, R12.

2. The remote wireless environmental monitoring and control unit according to claim 1, wherein Capacitor C1 is connected to pin 1 of reference source U1. Capacitor C4 and resistor R5 are connected in parallel and then connected to pins 2 and 3 of reference source U1. Resistor R2 is connected between reference source U1 and four-channel operational amplifier U2B. Capacitor C5, resistors R6 and R7 are connected in series and then connected between pin 5 and pin 7 of four-channel operational amplifier U2B.

3. The remote wireless environmental monitoring and control unit according to claim 1, characterized in that, Resistor R1 is connected between pin 1 of four-channel operational amplifier U2A and pin 5 of four-channel operational amplifier U2B. Resistors R3 and R4 are connected in series and then connected between pin 3 of four-channel operational amplifier U2A and pin 7 of four-channel operational amplifier U2B. Capacitors C2 and C3 are connected in parallel, with one end connected to pin 4 of four-channel operational amplifier U2A and the other end grounded. Capacitors C6 and C10 are connected in parallel, with one end connected to the IN1- terminal of four-channel operational amplifier U2A and the other end grounded.

4. The remote wireless environmental monitoring and control unit according to claim 1, characterized in that, Fuse F1 is connected between pin 3 of four-channel operational amplifier U2A and temperature sampling resistor J2.

5. The remote wireless environmental monitoring and control unit according to claim 1, characterized in that, Both ends of resistor R13 are respectively connected between pin 1 and pin 8 of instrumentation amplifier U5. Pin 1 of temperature sampling resistor J2 is connected to pin 2 of instrumentation amplifier U5. Pin 2 of temperature sampling resistor J2 is connected to pin 3 of instrumentation amplifier U5. Pin 5 of instrumentation amplifier U5 is grounded.

6. The remote wireless environmental monitoring and control unit according to claim 1, characterized in that, Pin 10 of four-channel operational amplifier U2C and pin 13 of four-channel operational amplifier U2D are both connected to pin 6 of instrumentation amplifier U5. And resistor R8 is connected between pin 10 of four-channel operational amplifier U2C and pin 6 of instrumentation amplifier U5. Resistor R10 is connected between pin 13 of four-channel operational amplifier U2D and pin 6 of instrumentation amplifier U5.

7. The remote wireless environmental monitoring and control unit according to claim 1, characterized in that Resistor R9 is connected between pin 9 and pin 8 of four-channel operational amplifier U2C. Resistor R10 is connected between pin 14 and pin 13 of four-channel operational amplifier U2D.

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