Temperature sampling circuit and device

Abstract

The utility model discloses a temperature sampling circuit and device, comprising a temperature sensor, a pull-up resistor connected in series with the temperature sensor, and a single-chip microcomputer, the voltage acquisition end of the single-chip microcomputer receives the partial voltage of the temperature sensor, and obtains the current temperature according to the partial voltage value; the temperature sampling circuit further comprises an expansion unit connected with the temperature sensor. The expansion unit is used for neutralizing the partial pressure of the temperature sensor. According to the utility model, the temperature sensor, the expansion unit and the pull-up resistor are jointly used for voltage division, and the expansion unit is used for neutralization, so that the voltage measured by the voltage acquisition end is transferred in a middle range, namely, the temperature of the front section and the probability that the rear section deviates from a standard value are reduced; therefore, the accuracy of front-section and rear-section temperature detection is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of temperature measurement, in particular to a temperature sampling circuit and a device. Background Art

[0002] At present, most temperature sampling circuits designed by electronic control use temperature sensors and pull-up resistors in series to obtain the current temperature by detecting the divided voltage. However, due to the nonlinear relationship between temperature and resistance in the temperature sensor, this temperature sampling circuit may result in inaccurate temperature detection at the front or back end, resulting in poor sampling accuracy at the detection port.

[0003] Therefore, the prior art still needs to be improved and developed. Utility Model Content

[0004] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a temperature sampling motor and device to solve the problem of inaccurate temperature detection in the front or rear section of the temperature sampling circuit in the prior art.

[0005] The technical solution of the utility model is as follows:

[0006] A temperature sampling circuit comprises a temperature sensor, a pull-up resistor connected in series with the temperature sensor, and a single-chip microcomputer, wherein a voltage acquisition terminal of the single-chip microcomputer receives a voltage division of the temperature sensor and obtains a current temperature according to the voltage division value; the temperature sampling circuit further comprises an expansion unit connected to the temperature sensor;

[0007] The expansion unit is used to neutralize the partial pressure of the temperature sensor.

[0008] According to a further configuration of the present invention, the expansion unit is connected in series with the temperature sensor.

[0009] According to a further configuration of the present invention, the expansion unit is connected in parallel with the temperature sensor.

[0010] In a further configuration of the present utility model, the expansion unit includes a first resistor and a second resistor;

[0011] One end of the first resistor is connected to the temperature sensor, and the other end of the first resistor is grounded;

[0012] One end of the second resistor is connected to the temperature sensor and the voltage collection end respectively, and the other end of the second resistor is grounded.

[0013] In a further configuration of the utility model, the expansion unit includes a first resistor, a second resistor, a third resistor and a fourth resistor;

[0014] One end of the first resistor is connected to the temperature sensor, and the other end of the first resistor is connected to one end of the third resistor;

[0015] One end of the second resistor is connected to the temperature sensor and the voltage collection end respectively, and the other end of the second resistor is connected to one end of the third resistor;

[0016] The other end of the third resistor is grounded;

[0017] One end of the fourth resistor is connected to the temperature sensor and the voltage collection end respectively, and the other end of the fourth resistor is grounded.

[0018] A further configuration of the utility model further includes a first filtering unit;

[0019] The first filtering unit is connected to the voltage collection terminal and is used for filtering the voltage division signal of the temperature sensor.

[0020] A further configuration of the utility model further includes a second filtering unit;

[0021] The second filtering unit is connected to the DC power supply and the pull-up resistor respectively, and is used for energy storage filtering of the DC power supply.

[0022] According to a further configuration of the present invention, the temperature sensor is a temperature-sensitive resistor.

[0023] According to a further configuration of the present invention, the accuracy of the expansion unit is greater than the accuracy of the temperature sensor.

[0024] The utility model also provides a temperature sampling device, comprising the temperature sampling circuit as described above.

[0025] The utility model provides a temperature sampling circuit and device, including a temperature sensor, a pull-up resistor connected in series with the temperature sensor, and a single-chip microcomputer, wherein the voltage acquisition terminal of the single-chip microcomputer receives the voltage division of the temperature sensor and obtains the current temperature according to the voltage division value; the temperature sampling circuit also includes an expansion unit connected to the temperature sensor; the expansion unit is used to neutralize the voltage division of the temperature sensor. The utility model divides the voltage of the pull-up resistor together with the temperature sensor and the expansion unit, and the expansion unit performs neutralization to transfer the voltage measured by the voltage acquisition terminal to the middle range, that is, to reduce the probability of the front section temperature and the rear section temperature deviating from the standard value, thereby improving the accuracy of the front section and rear section temperature detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary personnel in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0027] Figure 1 It is a structural diagram of the temperature sampling circuit in the utility model.

[0028] Figure 2 It is a circuit diagram of a series embodiment of the utility model.

[0029] Figure 3 It is a circuit diagram of a parallel embodiment of the utility model.

[0030] Figure 4 It is a circuit diagram of a series-parallel embodiment of the utility model.

[0031] Figure 5 It is a circuit diagram of multiple sets of structural embodiments in the utility model.

[0032] The marks in the accompanying drawings are: 100, expansion unit; 200, first filter unit; 300, second filter unit; RT, temperature sensor; RX, pull-up resistor; R1, first resistor; R2, second resistor; R3, third resistor; R4, fourth resistor; P1, voltage acquisition terminal; C1, first filter capacitor; C2, second filter capacitor; VCC, DC power supply. DETAILED DESCRIPTION

[0033] The present invention provides a temperature sampling circuit and device. In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described here are only used to explain the present invention and are not used to limit the present invention.

[0034] In the embodiments and patent claims, unless the article is specifically limited in the text, "a", "an", "said" and "the" may also include plural forms. If there are descriptions involving "first", "second", etc. in the embodiments of the utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0035] It should be further understood that the term "comprising" used in the specification of the present utility model refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when we refer to an element as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there can also be intermediate elements. In addition, the "connection" or "coupling" used here can include wireless connection or wireless coupling. The term "and / or" used here includes all or any unit and all combinations of one or more associated listed items.

[0036] Those skilled in the art will understand that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as the general understanding of ordinary technicians in the field to which the utility model belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as the meaning in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as here.

[0037] In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0038] The inventors have found that for temperature sensors, the general temperature curve is a nonlinear relationship. If the resistance value is too large or too small, it will directly affect the inaccurate temperature conversion. In the electronic control design, field effect tubes are needed to control the current. If the accuracy is not enough, the software cannot make a correct judgment in time through the temperature sampling circuit, so that the field effect tube burns out, making the entire product scrapped.

[0039] In view of the above technical problems, the utility model provides a preferred embodiment of a temperature sampling circuit.

[0040] See also Figure 1The utility model provides a temperature sampling circuit, including a temperature sensor RT, a pull-up resistor RX connected in series with the temperature sensor RT, and a single-chip microcomputer. The voltage acquisition terminal P1 of the single-chip microcomputer receives the divided voltage of the temperature sensor RT and obtains the current temperature according to the divided voltage value. The temperature sampling circuit also includes an expansion unit 100 connected to the temperature sensor RT; the expansion unit 100 is used to neutralize the divided voltage of the temperature sensor RT to reduce the probability of the front-end temperature and the back-end deviating from the standard value. Wherein, neutralizing the divided voltage of the temperature sensor means that when the temperature sensor is too large, the collected voltage of the voltage acquisition terminal is reduced to within the middle range, and when the temperature sensor is too small, the collected voltage of the voltage acquisition terminal is increased to within the middle range.

[0041] Specifically, the voltage acquisition terminal P1 is connected to the temperature sensor RT, and the extension unit 100 is connected to the temperature sensor RT. When the voltage acquisition terminal P1 performs acquisition, the collected voltage is the voltage divided by the combined structure of the extension unit 100 and the temperature sensor RT and the pull-up resistor RX. It can be understood that, in this embodiment, the voltage collected by the voltage acquisition terminal P1 is not only the voltage of the temperature sensor RT, but also the influence of the extension unit 100. As shown in Table 1, if only one of the temperature sensor RT and the pull-up resistor RX performs voltage division, the probability of being larger than the standard value (the latter section deviates from the standard value) is one third, and the probability of being smaller than the standard value (the former section deviates from the standard value) is one third. If the temperature sensor RT is connected to the expansion unit 100, as shown in Table 2, the temperature sensor RT and the expansion unit 100 divide the voltage together with the pull-up resistor RX, then the probability that the voltage detection end is larger than the standard value (the latter section deviates from the standard value) is one in nine, that is, the probability that the standard value of the temperature sensor RT is larger than that of the expansion unit 100 is one in nine. Similarly, the probability that the voltage detection end is smaller than the standard value (the former section deviates from the standard value) is one in nine, thereby reducing the probability of the former section and the latter section deviating from the standard value, thereby improving the accuracy of temperature detection within the former section range and the latter section range.

[0042] Table 1

[0043] The measured value and the standard value when the temperature sensor RT is divided by the voltage divider resistor Temperature Sensor RT Too big normal Small

[0044] Table 2

[0045]

[0046] In one embodiment, the extension unit 100 is connected in series with the temperature sensor RT.

[0047] Specifically, the temperature sensor RT is a temperature sensitive resistor, and the extension unit 100 may be a resistor. Figure 2 As shown, after the extension unit 100 is connected in series with the temperature sensor RT, the voltage collected by the voltage acquisition terminal P1 is the voltage after the extension unit 100 is connected in series with the temperature sensor RT. If the induced temperature of the temperature sensor RT is within the front range or within the rear range, the extension unit 100 is used for neutralization to transfer the voltage measured by the voltage acquisition terminal P1 to the middle range, that is, to reduce the probability of the front temperature and the rear deviation from the standard value. Due to the temperature curve characteristics of the temperature sensor RT, when the temperature interval is in the middle, the voltage and temperature conversion are closer to linear, that is, when the voltage measured by the voltage acquisition terminal P1 is in the middle temperature interval, the temperature accuracy is higher. Therefore, in this embodiment, by connecting the extension unit 100 in series with the temperature sensor RT, the probability of the front temperature (too small) and the rear temperature (too large) deviating from the standard value can be reduced, thereby improving the accuracy within the front temperature range and the rear temperature range. Furthermore, by connecting the extension unit 100 in series with the temperature sensor RT, the overall voltage is increased, and thus the accuracy within the front temperature range can be further improved.

[0048] In one embodiment, the extension unit 100 is connected in parallel with the temperature sensor RT.

[0049] Specifically, the extension unit 100 may be a resistor. Figure 3 As shown, the extension unit 100 is connected in parallel with the temperature sensor RT. The voltage collected by the voltage collection terminal P1 is the voltage after the extension unit 100 and the temperature sensor RT are connected in series. Similarly, by neutralizing with the extension unit 100, the probability of the front temperature (too small) and the rear temperature (too large) deviating from the standard value can also be reduced, thereby improving the accuracy within the front temperature range and the rear temperature range. And by connecting the extension unit 100 in parallel with the temperature sensor RT, the overall voltage is reduced as a whole, so the accuracy within the rear temperature range can be further improved.

[0050] In one embodiment, if Figure 4 As shown, the extension unit 100 includes a first resistor R1 and a second resistor R2; one end of the first resistor R1 is connected to the temperature sensor RT, and the other end of the first resistor R1 is grounded; one end of the second resistor R2 is respectively connected to the temperature sensor RT and the voltage acquisition terminal P1, and the other end of the second resistor R2 is grounded.

[0051] Specifically, in this embodiment, the expansion unit 100 is first connected in series with the temperature sensor RT and then connected in parallel. As can be seen from the above, whether it is connected in series or in parallel, the probability of the front temperature and the rear temperature deviating from the standard value will be reduced to one-ninth. Then when the variables become three, the probability of the front temperature and the rear temperature deviating from the standard value will become one-twenty-seventh (probability P=3^3), further improving the accuracy within the front temperature range and the rear temperature range.

[0052] In one embodiment, if Figure 5 As shown, the extension unit 100 includes a first resistor R1, a second resistor R2, a third resistor R3 and a fourth resistor R4; one end of the first resistor R1 is connected to the temperature sensor RT, and the other end of the first resistor R1 is connected to one end of the third resistor R3; one end of the second resistor R2 is respectively connected to the temperature sensor RT and the voltage acquisition terminal P1, and the other end of the second resistor R2 is connected to one end of the third resistor R3; the other end of the third resistor R3 is grounded; one end of the fourth resistor R4 is respectively connected to the temperature sensor RT and the voltage acquisition terminal P1, and the other end of the fourth resistor R4 is grounded.

[0053] Specifically, in this embodiment, two sets of series-parallel structures are used. Similarly, when two sets of series-parallel structures are used, the variables have become five, then the probability of the front temperature and the rear temperature deviating from the standard value will be reduced to one-two-hundred-and-forty-one-third (probability P=3^5), further improving the accuracy within the front temperature range and the rear temperature range. It should be noted that the present application is not limited to two sets of series-parallel structures, and can be set according to actual conditions. The more series-parallel resistors there are, the higher the accuracy within the front temperature range and the rear temperature range.

[0054] In one embodiment, if Figure 4 As shown, the temperature sampling circuit further includes a first filtering unit 200; the first filtering unit 200 is connected to the voltage collection terminal P1, and is used to filter the voltage division signal of the temperature sensor RT.

[0055] Specifically, the first filtering unit 200 is a first filtering capacitor C1, one end of which is connected to the temperature sensor RT and the voltage acquisition terminal P1 respectively, and the other end of the first filtering capacitor C1 is grounded. The first filtering capacitor C1 filters the voltage-divided signal before entering the voltage acquisition terminal P1 to filter out interference signals and avoid errors in the voltage detection terminal detecting the voltage.

[0056] In one embodiment, if Figure 4As shown, the temperature sampling circuit further includes a second filtering unit 300; the second filtering unit 300 is respectively connected to the DC power supply VCC and the pull-up resistor RX, and is used for energy storage filtering of the DC power supply VCC.

[0057] Specifically, the first filtering unit 200 is a second filtering capacitor C2, one end of the second filtering capacitor C2 is connected to the DC power supply VCC and the pull-up resistor RX respectively, and the other end of the second filtering capacitor C2 is grounded. The DC power supply VCC is filtered by the second filtering capacitor C2 to provide a stable DC signal. And the second filtering capacitor C2 can also store energy of the DC power supply VCC.

[0058] In one embodiment, the accuracy of the temperature sensor RT is greater than the accuracy of the extension unit 100 .

[0059] Specifically, the extension unit 100 may be a linear resistor, and the voltage and resistance may be converted more accurately to further improve the accuracy of the front-end and rear-end temperature detection.

[0060] The utility model also provides a temperature sampling circuit and device, including the temperature sampling circuit as described above. The temperature sampling device can be installed at a location where the device needs to collect temperature values, and is used to collect the temperature values ​​of the device in real time, and can be specifically set according to actual needs.

[0061] In summary, the temperature sampling circuit and device provided by the utility model include a temperature sensor, a pull-up resistor connected in series with the temperature sensor, and a single-chip microcomputer, wherein the voltage acquisition terminal of the single-chip microcomputer receives the divided voltage of the temperature sensor and obtains the current temperature according to the divided voltage value; the temperature sampling circuit also includes an expansion unit connected to the temperature sensor; the expansion unit is used to neutralize the divided voltage of the temperature sensor. The utility model divides the voltage of the pull-up resistor together with the temperature sensor and the expansion unit, and the expansion unit performs neutralization to transfer the voltage measured by the voltage acquisition terminal to the middle range, that is, to reduce the probability of the front-end temperature and the rear-end temperature deviating from the standard value, thereby improving the accuracy of the front-end and rear-end temperature detection.

[0062] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made according to the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A temperature sampling circuit, comprising a temperature sensor, a pull-up resistor connected in series with the temperature sensor, and a single-chip microcomputer, wherein a voltage acquisition terminal of the single-chip microcomputer receives a voltage division of the temperature sensor and obtains a current temperature according to the voltage division value; characterized in that: The temperature sampling circuit further includes an expansion unit connected to the temperature sensor, and the expansion unit is used to neutralize the divided voltage of the temperature sensor.

2. The temperature sampling circuit according to claim 1, characterized in that: The expansion unit is connected in series with the temperature sensor.

3. The temperature sampling circuit according to claim 1, characterized in that: The expansion unit is connected in parallel with the temperature sensor.

4. The temperature sampling circuit according to claim 1, characterized in that: The expansion unit includes a first resistor and a second resistor; One end of the first resistor is connected to the temperature sensor, and the other end of the first resistor is grounded; One end of the second resistor is connected to the temperature sensor and the voltage collection end respectively, and the other end of the second resistor is grounded.

5. The temperature sampling circuit according to claim 1, characterized in that: The expansion unit includes a first resistor, a second resistor, a third resistor and a fourth resistor; One end of the first resistor is connected to the temperature sensor, and the other end of the first resistor is connected to one end of the third resistor; One end of the second resistor is connected to the temperature sensor and the voltage collection end respectively, and the other end of the second resistor is connected to one end of the third resistor; The other end of the third resistor is grounded; One end of the fourth resistor is connected to the temperature sensor and the voltage collection end respectively, and the other end of the fourth resistor is grounded.

6. The temperature sampling circuit according to claim 1, characterized in that: Also includes a first filtering unit; The first filtering unit is connected to the voltage collection terminal and is used for filtering the voltage division signal of the temperature sensor.

7. The temperature sampling circuit according to claim 1, characterized in that: Also includes a second filtering unit; The second filtering unit is connected to the DC power supply and the pull-up resistor respectively, and is used for energy storage filtering of the DC power supply.

8. The temperature sampling circuit according to claim 1, characterized in that: The temperature sensor is a temperature sensitive resistor.

9. The temperature sampling circuit according to claim 1, characterized in that: The accuracy of the expansion unit is greater than the accuracy of the temperature sensor.

10. A temperature sampling device, characterized in that: The method comprises a temperature sampling circuit as described in any one of claims 1 to 9.

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