CN218547361U - Constant temperature control circuit, constant temperature control chip and electronic equipment - Google Patents
Constant temperature control circuit, constant temperature control chip and electronic equipment Download PDFInfo
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- CN218547361U CN218547361U CN202223036873.7U CN202223036873U CN218547361U CN 218547361 U CN218547361 U CN 218547361U CN 202223036873 U CN202223036873 U CN 202223036873U CN 218547361 U CN218547361 U CN 218547361U
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Abstract
The utility model provides a constant temperature control circuit, constant temperature control chip and electronic equipment, wherein, constant temperature control circuit includes: the temperature measuring circuit, the constant temperature presetting circuit, the temperature comparison circuit, the drive circuit and the relay; the first end of the temperature measuring circuit is connected with a power supply; the first ends of the constant temperature preset circuit, the temperature comparison circuit and the relay are connected to a common connecting end of the temperature measuring circuit and the power supply; the second ends of the temperature measuring circuit and the constant temperature presetting circuit are both grounded; the third end of the temperature measuring circuit is connected with the second end of the temperature comparison circuit; the third end of the constant temperature preset circuit is connected with the third end of the temperature comparison circuit; the fourth end of the temperature comparison circuit is connected with the first end of the drive circuit; the second end of the relay is connected with the third end of the driving circuit; the second end of the driving circuit is grounded. The utility model discloses according to actual temperature and predetermined temperature's error to thereby adjust through the relay and reach homothermal effect, and circuit design is simple, stable performance.
Description
Technical Field
The utility model relates to a thermostatic control technical field especially relates to a thermostatic control circuit, thermostatic control chip and electronic equipment.
Background
The constant temperature control circuit is widely applied to the fields of medical treatment, automobiles, household appliances, scientific research and the like. When the constant temperature control circuit executes the temperature control function, when the temperature reaches the set temperature, the constant temperature control circuit can control the actual temperature value to float in a small range within the range of the set temperature value.
The conventional constant temperature control circuits are of various types, and are usually implemented by an Integrated Circuit (IC), which is easily limited by IC suppliers, and the circuits are complex and high in cost, resulting in limited practicability and applicability.
SUMMERY OF THE UTILITY MODEL
The utility model provides a constant temperature control circuit, constant temperature control chip and electronic equipment aims at solving the complicated integrated circuit chip, the higher problem of cost that just rely on the specialty of constant temperature control circuit design among the correlation technique.
In order to solve the technical problem, a first aspect of the embodiments of the present invention provides a constant temperature control circuit, which is characterized by comprising: the temperature measuring circuit, the constant temperature presetting circuit, the temperature comparison circuit, the driving circuit and the relay;
the first end of the temperature measuring circuit is electrically connected with the power supply; the first ends of the constant temperature preset circuit, the temperature comparison circuit and the relay are electrically connected to the common connecting end of the temperature measuring circuit and the power supply; the second ends of the temperature measuring circuit and the constant temperature preset circuit are grounded; the third end of the temperature measuring circuit is electrically connected with the second end of the temperature comparison circuit; the third end of the constant temperature preset circuit is electrically connected with the third end of the temperature comparison circuit; the fourth end of the temperature comparison circuit is electrically connected with the first end of the driving circuit; the second end of the relay is electrically connected with the third end of the driving circuit; the second end of the driving circuit is grounded.
Further, the temperature measuring circuit comprises: a first resistor and a temperature sensor; one end of the temperature sensor is electrically connected with one end of the first resistor; the other end of the temperature sensor is electrically connected with the power supply; the other end of the first resistor is grounded; and the common connecting end of the temperature sensor and the first resistor is the third end of the temperature measuring circuit.
Further, the constant temperature preset circuit includes: the second resistor, the third resistor and the first adjustable resistor; the second resistor is electrically connected with one end of the third resistor, and the other end of the third resistor is electrically connected with the power supply; the other end of the third resistor is electrically connected with the first adjustable resistor; the other end of the first adjustable resistor is grounded; and the common connecting end of the second resistor and the third resistor is the third end of the constant temperature preset circuit.
Further, the temperature comparison circuit includes: the comparator, the second adjustable resistor and the fourth resistor; one end of the second adjustable resistor is electrically connected with one end of the fourth resistor, and the other end of the second adjustable resistor is electrically connected with the first end of the comparator; the other end of the fourth resistor is electrically connected with the fourth end of the comparator; and the third end of the comparator is connected with the power supply, and the fifth end of the comparator is grounded.
Furthermore, the second end of the comparator is an inverting input end and is electrically connected with the third end of the temperature measuring circuit; the first end of the comparator is a positive phase input end and is electrically connected with the third end of the constant temperature preset circuit; the fourth terminal of the comparator is the fourth terminal of the temperature comparison circuit.
Further, the constant temperature control circuit further comprises: the capacitor, the first crystal diode and the fifth resistor; one end of the fifth resistor is electrically connected with the first end of the temperature comparison circuit, and the other end of the fifth resistor is electrically connected with the first end of the constant temperature preset circuit; a first common connecting end of the anode of the capacitor and the cathode of the first crystal diode is electrically connected with a common connecting end of the constant temperature preset circuit and the fifth resistor; and a second common connecting end, electrically connected with the cathode of the capacitor and the anode of the first crystal diode, is grounded.
Further, the driving circuit includes: an NPN transistor and a second transistor diode; the second crystal diode is electrically connected between the base electrode and the emitting electrode of the NPN crystal triode; the base electrode of the NPN transistor is electrically connected with the fourth end of the temperature comparison circuit; and the collector of the NPN transistor is electrically connected with the second end of the relay.
Further, the constant temperature control circuit further comprises: a third transistor diode and a sixth resistor; the third transistor diode is connected in parallel with the relay; the sixth resistor is electrically connected between the base of the NPN transistor and the fourth end of the temperature comparison circuit.
The embodiment of the utility model provides a second aspect provides a constant temperature control chip, include if the embodiment of the utility model provides a first aspect the constant temperature control circuit.
The embodiment of the utility model provides an embodiment third aspect provides an electronic equipment, include like the utility model discloses embodiment first aspect the constant temperature control circuit or like the embodiment second aspect the constant temperature control chip.
From the above description, compared with the related art, the beneficial effects of the present invention lie in:
in the embodiment, the actual temperature obtained by the temperature measuring circuit and the set temperature obtained by the constant temperature presetting circuit are conveyed to the temperature comparison circuit, and the temperature error signal obtained through comparison enables the driving circuit to control the relay to work to adjust the temperature after passing through the driving circuit, so that the effect of constant temperature control is achieved, and the circuit is simple in design, stable in performance and low in overall cost.
Drawings
Fig. 1 is a schematic circuit diagram of a thermostatic control circuit according to an embodiment of the present invention;
fig. 2 is a schematic circuit diagram of another thermostatic control circuit according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. Furthermore, the technical features mentioned in the embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.
In the related art, there is a problem that the constant temperature control circuit is complicated in design and depends on a professional integrated circuit chip, so that the manufacturing cost is high. Therefore, the embodiment of the utility model provides a constant temperature control circuit.
Referring to fig. 1, a constant temperature control circuit according to an embodiment of the present invention includes: the temperature measuring circuit 100, the constant temperature preset circuit 200, the temperature comparison circuit 300, the drive circuit 400 and the relay JD1.
Specifically, a first end of the temperature measuring circuit 100 is electrically connected to the power supply; the constant temperature preset circuit 200, the temperature comparison circuit 300 and the first end 3 of the relay JD1 are all electrically connected to the common connecting end of the temperature measuring circuit 100 and the power supply; the second ends of the temperature measuring circuit 100 and the constant temperature presetting circuit 200 are grounded; the third end of the temperature measuring circuit 100 is electrically connected with the second end of the temperature comparing circuit 300; the third end of the constant temperature preset circuit 200 is electrically connected with the third end of the temperature comparison circuit 300; the fourth end of the temperature comparison circuit 300 is electrically connected to the first end of the driving circuit 400; the second terminal 1 of the relay JD1 is electrically connected to the third terminal of the driving circuit 400; the second terminal of the driving circuit 400 is grounded.
In this embodiment, the temperature measuring circuit 100 is configured to measure an actual temperature value, the constant temperature presetting circuit 200 is configured to set a constant temperature value, the actual temperature value obtained by the temperature measuring circuit 100 and the set temperature value obtained by the constant temperature presetting circuit 200 are transmitted to the temperature comparing circuit 300, and a temperature error signal obtained through comparison makes the driving circuit 400 control the relay JD1 to operate to adjust an actual temperature after passing through the driving circuit 400, so that the actual temperature is close to the preset temperature value.
Further, referring to fig. 2, the temperature measuring circuit 100 includes: a first resistor R1 and a temperature sensor F1.
Specifically, one end of the temperature sensor F1 is electrically connected to one end of the first resistor R1; the other end of the temperature sensor F1 is electrically connected with a power supply; the other end of the first resistor R1 is grounded; the common connection end of the temperature sensor F1 and the first resistor R1 is the third end of the temperature measuring circuit 100.
In this embodiment, the temperature sensor F1 is connected in series with the first resistor R1, and the third terminal of the temperature measuring circuit 100 is the output terminal of the circuit. When the temperature sensor F1 measures the actual temperature value, the voltage corresponding to the actual temperature value is transmitted to the next circuit through the output end after being divided by the first resistor R1. The temperature sensor F1 of this embodiment is of a type VA0565, the first resistor R1 is a fixed resistor, the rated resistance is 1K Ω, and the power supply voltage is 15V.
Further, referring to fig. 2, the constant temperature preset circuit 200 includes: a second resistor R2, a third resistor R3 and a first adjustable resistor W1.
Specifically, one end of the second resistor R2 is electrically connected to one end of the third resistor R3, and the other end is electrically connected to the power supply; the other end of the third resistor R3 is electrically connected with the first adjustable resistor W1; the other end of the first adjustable resistor W1 is grounded; the common connection end of the second resistor R2 and the third resistor R3 is the third end of the constant temperature preset circuit 200.
In this embodiment, the second resistor R2, the third resistor R3 and the first adjustable resistor W1 are connected in series, and the third end of the constant temperature preset circuit 200 is an output end. Through adjusting first adjustable resistance W1, can set up suitable constant temperature point according to the wish, for example 20 degrees, the corresponding resistance value of different constant temperature points is different, and corresponding voltage is also different, and the voltage value of this circuit is sent to next circuit through the output finally. In this embodiment, the rated resistance of the first adjustable resistor W1 is 560 Ω, the second resistor R2 and the third resistor R3 are fixed resistances, the rated resistance of the second resistor R2 is 56K Ω, and the rated resistance of the second resistor R2 is 560 Ω.
Further, referring to fig. 2, the temperature comparison circuit 300 includes: comparator IC1, second adjustable resistor W2 and fourth resistor R4.
Specifically, one end of the second adjustable resistor W1 is electrically connected to one end of the fourth resistor R4, and the other end is electrically connected to the first end 1 of the comparator IC 1; the other end of the fourth resistor R4 is electrically connected with the fourth end of the comparator IC 1; the third terminal 3 of the comparator IC1 is connected to the power supply, and the fifth terminal 5 is grounded.
Further, referring to fig. 2, the second terminal 2 of the comparator IC1 is an inverting input terminal and is electrically connected to the third terminal of the temperature measuring circuit 100; the first end 1 of the comparator IC1 is a positive phase input end and is electrically connected with the third end of the constant temperature preset circuit 200; the fourth terminal 4 of the comparator IC1 is the fourth terminal of the temperature comparison circuit 300.
In this embodiment, the fourth terminal of the temperature comparison circuit 300 is an output terminal, the voltage corresponding to the actual temperature value of the temperature measurement circuit 100 is sent to the inverting input terminal of the comparator IC1, the voltage corresponding to the temperature value set by the constant temperature preset circuit 200 is sent to the non-inverting input terminal of the comparator IC1, and the comparator IC1 compares the two voltage values to obtain a voltage value corresponding to the temperature error, and sends the voltage value to the next circuit through the output terminal. The second adjustable resistor W2 and the fourth resistor R4 are two feedback resistors of the comparator IC1, and are used for adjusting the sensitivity of the comparator IC1, and by adjusting the sensitivity, the comparator IC1 can be adjusted to be insensitive or sensitive when the actual temperature reaches the preset temperature value. The comparator IC1 of this embodiment is a model SOP8, the second adjustable resistor W2 is rated to have a resistance value of 560 Ω, and the fourth resistor R4 is a fixed resistor and is rated to have a resistance value of 4.7M Ω.
Further, referring to fig. 2, the thermostatic control circuit further includes: a capacitor C1, a first transistor diode D1 and a fifth resistor R5.
Specifically, one end of the fifth resistor R5 is electrically connected to the first end of the temperature comparison circuit 300, and the other end is electrically connected to the first end of the constant temperature preset circuit 200; a first common connection end of the anode of the capacitor C1 and the cathode of the first crystal diode D1 is electrically connected to a common connection end of the constant temperature preset circuit 200 and the fifth resistor R5; the second common connection end, which electrically connects the cathode of the capacitor C1 and the anode of the first transistor D1, is grounded.
In this embodiment, the capacitor C1 is connected in parallel with the first crystal diode D1, and the first crystal diode D1 is used for reverse protection, that is, when a reverse direction occurs in the circuit, the first crystal diode D1 can effectively block the reverse protection to achieve the purpose of protection; the capacitor C1 is used for filtering, the fifth resistor R5 is a current limiting resistor, and the combination of the fifth resistor R5 and the capacitor C1 can make the power supply voltage smoother. IN this embodiment, the rated resistance of the fifth resistor R5 is 12K Ω, the model of the capacitor C1 is ec.6, the rated voltage is 47uF, and the model of the first crystal diode D1 is IN4149.
Further, referring to fig. 2, the driving circuit 400 includes: an NPN transistor Q1 and a second transistor diode D2.
Specifically, the second transistor D2 is electrically connected between the base and the emitter of the NPN transistor Q1; the base of the NPN transistor Q1 is electrically connected with the fourth end of the temperature comparison circuit 300; the collector of the NPN transistor Q1 is electrically connected to the second terminal 1 of the relay JD1.
In this embodiment, the anode of the second transistor D2 is electrically connected to the base of the NPN transistor Q1, and the cathode of the second transistor D2 is electrically connected to the emitter of the NPN transistor Q1. After the voltage corresponding to the temperature error of the temperature comparison circuit 300 is transmitted to the base of the NPN transistor Q1 via the output terminal, the NPN transistor Q1 is turned on and drives the relay JD1 to operate. The second transistor D2 is used to protect the NPN transistor Q1, and can filter the ac voltage in the circuit to obtain a dc voltage. The model of the second transistor D2 is IN4149, the model of the NPN transistor Q1 is BC140, the model of the relay is JD-1-2-5P, the relay includes a first pin 1, a second pin 2, a third pin 3, a fourth pin 4, and a fifth pin 5, wherein the second pin 2, the fourth pin 4, and the fifth pin 5 are IN an off state, when an actual temperature is close to or consistent with a preset temperature, a pointer of the relay points to the second pin 2, the fourth pin 4, or the fifth pin 5, and the first pin 1 and the third pin 3 of the relay are disconnected, so that the relay stops working.
Still further, referring to fig. 2, the thermostatic control circuit further includes: a third transistor diode D3 and a sixth resistor R6.
Specifically, the third transistor diode D3 is connected in parallel with the relay JD 1; the sixth resistor R6 is electrically connected between the base of the NPN transistor Q1 and the fourth terminal of the temperature comparison circuit 300.
In this embodiment, the cathode of the third photodiode D3 is electrically connected to the first terminal 3 of the relay, and the anode of the third photodiode D3 is electrically connected to the second terminal 1 of the relay. The third transistor D3 is used to block the reverse induced electromotive force generated by the coil in the relay JD1, so that the relay JD1 is more sensitive. IN this embodiment, the third transistor diode D3 has a model number IN4149, the sixth resistor R6 is a fixed resistor, and the rated resistance value is 33K Ω.
The embodiment of the utility model provides a constant temperature control circuit, the temperature value of temperature measurement circuit 100 measurement reality, constant temperature preset circuit 200 sets up invariable temperature value, through the actual temperature value that obtains temperature measurement circuit 100, constant temperature preset circuit 200 obtains setting for the temperature value and carries temperature comparison circuit 300, the temperature error signal that obtains through the comparison, this temperature error signal makes drive circuit 400 control relay JD1 work in order to adjust actual temperature behind drive circuit 400, make this actual temperature close with the temperature value of predetermineeing. By using common circuit elements and simple circuit design, not only can the constant temperature control be stably and reliably carried out, but also the cost can be effectively reduced.
The embodiment of the utility model provides a still provide an electronic equipment, this electronic equipment includes above-mentioned thermostatic control circuit or thermostatic control circuit chip. The electronic device may include, but is not limited to, a mobile phone, a tablet computer, a notebook computer, a desktop computer, an intelligent learning machine, and an intelligent wearable device.
It should be noted that the embodiments of the present invention are described in a progressive manner, each embodiment focuses on the differences from the other embodiments, and the same and similar parts among the embodiments are referred to each other.
It is further noted that, in the present disclosure, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising a … …" does not exclude the presence of another identical element in a process, method, article, or apparatus that comprises the element.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. A thermostatic control circuit, comprising: the temperature measuring circuit, the constant temperature presetting circuit, the temperature comparison circuit, the drive circuit and the relay;
the first end of the temperature measuring circuit is electrically connected with the power supply; the first ends of the constant temperature preset circuit, the temperature comparison circuit and the relay are electrically connected to a common connecting end of the temperature measuring circuit and the power supply; the second ends of the temperature measuring circuit and the constant temperature presetting circuit are both grounded; the third end of the temperature measuring circuit is electrically connected with the second end of the temperature comparing circuit; the third end of the constant temperature preset circuit is electrically connected with the third end of the temperature comparison circuit; the fourth end of the temperature comparison circuit is electrically connected with the first end of the driving circuit; the second end of the relay is electrically connected with the third end of the driving circuit; the second end of the driving circuit is grounded.
2. The thermostatic control circuit of claim 1, wherein the thermometry circuit comprises: a first resistor and a temperature sensor; one end of the temperature sensor is electrically connected with one end of the first resistor; the other end of the temperature sensor is electrically connected with the power supply; the other end of the first resistor is grounded; and the common connecting end of the temperature sensor and the first resistor is the third end of the temperature measuring circuit.
3. The thermostatic control circuit of claim 1, wherein the constant temperature preset circuit comprises: the second resistor, the third resistor and the first adjustable resistor; the second resistor is electrically connected with one end of the third resistor, and the other end of the third resistor is electrically connected with the power supply; the other end of the third resistor is electrically connected with the first adjustable resistor; the other end of the first adjustable resistor is grounded; and the common connecting end of the second resistor and the third resistor is the third end of the constant temperature preset circuit.
4. The thermostatic control circuit of claim 1, wherein the temperature comparison circuit comprises: the comparator, the second adjustable resistor and the fourth resistor; one end of the second adjustable resistor is electrically connected with one end of the fourth resistor, and the other end of the second adjustable resistor is electrically connected with the first end of the comparator; the other end of the fourth resistor is electrically connected with the fourth end of the comparator; and the third end of the comparator is connected with the power supply, and the fifth end of the comparator is grounded.
5. The constant temperature control circuit according to claim 4, wherein the second terminal of the comparator is an inverting input terminal electrically connected to the third terminal of the temperature measurement circuit; the first end of the comparator is a positive phase input end and is electrically connected with the third end of the constant temperature preset circuit; the fourth terminal of the comparator is the fourth terminal of the temperature comparison circuit.
6. The thermostat control circuit of claim 1, further comprising: the capacitor, the first crystal diode and the fifth resistor; one end of the fifth resistor is electrically connected with the first end of the temperature comparison circuit, and the other end of the fifth resistor is electrically connected with the first end of the constant temperature preset circuit; a first common connecting end of the anode of the capacitor and the cathode of the first crystal diode is electrically connected with a common connecting end of the constant temperature preset circuit and the fifth resistor; and the cathode of the capacitor is grounded through a second common connecting end electrically connected with the anode of the first crystal diode.
7. The thermostatic control circuit of claim 1, wherein the drive circuit comprises: an NPN transistor and a second transistor diode; the second crystal diode is electrically connected between the base electrode and the emitting electrode of the NPN crystal triode; the base electrode of the NPN transistor is electrically connected with the fourth end of the temperature comparison circuit; and the collector of the NPN transistor is electrically connected with the second end of the relay.
8. The thermostat control circuit of claim 7, further comprising: a third transistor diode and a sixth resistor; the third transistor diode is connected in parallel with the relay; the sixth resistor is electrically connected between the base of the NPN transistor and the fourth end of the temperature comparison circuit.
9. A thermostatic control chip comprising a thermostatic control circuit according to any of claims 1 to 8.
10. An electronic device comprising a thermostat control circuit according to any one of claims 1 to 8 or a thermostat control chip according to claim 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223036873.7U CN218547361U (en) | 2022-11-14 | 2022-11-14 | Constant temperature control circuit, constant temperature control chip and electronic equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223036873.7U CN218547361U (en) | 2022-11-14 | 2022-11-14 | Constant temperature control circuit, constant temperature control chip and electronic equipment |
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| Publication Number | Publication Date |
|---|---|
| CN218547361U true CN218547361U (en) | 2023-02-28 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202223036873.7U Active CN218547361U (en) | 2022-11-14 | 2022-11-14 | Constant temperature control circuit, constant temperature control chip and electronic equipment |
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| Country | Link |
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| CN (1) | CN218547361U (en) |
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- 2022-11-14 CN CN202223036873.7U patent/CN218547361U/en active Active
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