WO2017000295A1

WO2017000295A1 - Electronic clinical thermometer and control method therefor

Info

Publication number: WO2017000295A1
Application number: PCT/CN2015/083138
Authority: WO
Inventors: 文孟军
Original assignee: 深圳市谷玛鹤健康科技有限公司
Priority date: 2015-07-02
Filing date: 2015-07-02
Publication date: 2017-01-05

Abstract

An electronic clinical thermometer comprises a wireless control chip (1), a thermistor (3), a reference resistor (2), and a capacitor (4). The wireless control chip (1) comprises a first control end (PIO1), a second control end (PIO2), and a third control end (PIO3). The first control end (PIO1) is connected to one end of the reference resistor (2), the second control end (PIO2) is connected to one end of the thermistor (3), the other end of the reference resistor (2) and the other end of the thermistor (3) are separately connected to one end of the capacitor (4), the other end of the capacitor (4) is grounded, and the third control end (PIO3) is connected to a common node of the reference resistor (2), the thermistor (3) and the capacitor (4). A method for controlling the electronic clinical thermometer. The wireless control chip (1) performs charging and discharging operations by alternatively controlling the reference resistor (2) and the capacitor (4); and the wireless control chip (1) performs charging and discharging operations by alternatively controlling the thermistor (3) and the capacitor (4), so as to acquire the surrounding temperature of the thermistor (3). In this manner, temperatures can be precisely measured by using low cost and low power consumption.

Description

Electronic thermometer and control method thereof

[Technical Field]

The invention relates to the field of medical and health, and in particular to an electronic thermometer and a control method thereof.

【Background technique】

In the field of electronic thermometers, temperature measurement values have conventionally been obtained by measuring changes in resistance of a thermistor accompanying temperature changes. Specifically, the temperature change is converted into a voltage or current change by a thermistor, then amplified and analog-digital converted, and finally the body temperature is calculated by a general-purpose micro-processing chip. With this method, since the accuracy of the measurement is determined by the accuracy of the thermistor and the accuracy of the power supply voltage, the accuracy is low. At the same time, due to the need to use analog-to-digital converters and voltage regulators during body temperature acquisition, power consumption is large.

[Summary of the Invention]

The technical problem to be solved by the present invention is to provide an electronic thermometer and a control method thereof, which can realize high-precision body temperature measurement at a lower cost and lower power consumption.

In order to solve the above technical problem, a technical solution adopted by the present invention is to provide an electronic thermometer including a wireless control chip, a thermistor, a reference resistor and a capacitor; the wireless control chip includes a first control end and a second control And a third control end; the first control end is connected to one end of the reference resistor, the second control end is connected to one end of the thermistor, the other end of the reference resistor, and the other end of the thermistor are respectively connected to one end of the capacitor, the capacitor The other end is grounded, and the third control terminal is connected to a common node of the reference resistor, the thermistor and the capacitor; wherein the wireless control chip performs charge and discharge operations and charge and discharge operations of the thermistor and the capacitor by alternately controlling the reference resistor and the capacitor. To get the temperature around the thermistor.

The electronic thermometer further includes an antenna, and the antenna is connected to the wireless control chip, and is configured to wirelessly transmit the temperature around the thermistor obtained by the wireless control chip.

Wherein, the electronic thermometer further comprises a battery and a switch, and the battery is connected to the wireless control chip through the switch, wherein the wireless control chip is powered on or off by the switch being opened or closed.

In order to solve the above technical problem, another technical solution adopted by the present invention is to provide a method for controlling an electronic thermometer, the method comprising: controlling, by a first control terminal of the wireless control chip, a high-low level control reference resistor and a capacitor. a charging and discharging operation to obtain a first charging and discharging time; and a second control terminal of the wireless control chip outputs a high and low level control the thermistor and the capacitor to perform a charging and discharging operation to obtain a second charging and discharging corresponding to the first charging and discharging time Performing a predetermined number of repeated operations on the two steps to obtain a plurality of first charging and discharging times and a second charging and discharging time; obtaining a ratio of each of the first charging and discharging times to a corresponding second charging and discharging time, which is recorded as a time ratio; obtaining an average of the first time ratios, recorded as a second time ratio; matching the second time ratio in the sample database to obtain a temperature around the thermistor, wherein the sample database includes the sample temperature and the sample The sample time ratio corresponding to the temperature.

The step of matching the second time ratio in the sample database to obtain the temperature around the thermistor is specifically: obtaining a time ratio of two samples adjacent to the second time ratio in the sample database, which is recorded as the first The ratio of the time to the second sample time, wherein the first sample time ratio is less than the second sample time ratio; obtaining the difference between the second time ratio and the first sample time ratio, recorded as the first difference; The difference between the ratio of the two sample time to the time of the first sample is recorded as the second difference; and the ratio of the ratio of the first difference to the second difference and the sample temperature corresponding to the first sample time ratio are obtained. The temperature around the thermistor.

Before the step of obtaining the ratio of each of the first charging and discharging time to the corresponding second charging and discharging time, the method further includes the steps of: obtaining a ratio of each of the first charging and discharging times to the corresponding second charging and discharging time, which is recorded as The three time ratios are obtained as the first mean value; the absolute value of the difference between each third time ratio and the first mean value is obtained as the first absolute value; the first absolute value is deleted. The third time ratio within a predetermined range is corresponding to the first charge and discharge time and the second charge and discharge time.

Before the step of obtaining the ratio of each of the first charging and discharging time to the corresponding second charging and discharging time, the method further includes the steps of: obtaining an average value of each of the first charging and discharging times, and recording the second average value; acquiring the first charging The absolute value of the difference between the discharge time and the second mean is recorded as the second absolute value; The first charge and discharge time and the corresponding second charge and discharge time are not in the second predetermined range.

Before the step of obtaining the ratio of each of the first charging and discharging time to the corresponding second charging and discharging time, the method further includes the steps of: obtaining an average value of each of the second charging and discharging times, and recording the third average value; acquiring each second charging The absolute value of the difference between the discharge time and the third mean is recorded as a third absolute value; the second charge and discharge time in which the third absolute value is not within the third predetermined range and the corresponding first charge and discharge time are deleted.

The step of obtaining the first charging and discharging time by the first control terminal of the wireless control chip to output the high and low level control reference resistors and capacitors to obtain the first charging and discharging time is specifically: controlling the first control end of the wireless control chip to output high power The capacitor is charged by the reference resistor and starts timing; when the wireless control chip detects that the third control terminal is high, the first control terminal of the control wireless control chip outputs a low level to discharge the capacitor through the reference resistor; When the wireless control chip detects that the third control terminal changes from a high level to a low level, the timing is stopped to obtain a first charging and discharging time.

Wherein, before the step of controlling the first control end of the wireless control chip to output a high level to charge the capacitor through the reference resistor and start timing, the method further includes: configuring the first control end to be an output mode, the second control end, and the first The third control terminal is an input mode; the first control terminal of the control wireless control chip outputs a low level and maintains the first predetermined time.

The step of controlling the thermistor and the capacitor to perform the charging and discharging operation to obtain the second charging and discharging time corresponding to the first charging and discharging time is specifically: controlling the second control end of the wireless control chip to output a high level to pass the thermal The resistor charges the capacitor and starts timing; when the wireless control chip detects that the third control terminal is high, the second control terminal of the control wireless control chip outputs a low level to discharge the capacitor through the thermistor; when the wireless control When the chip detects that the third control terminal changes from a high level to a low level, the timing is stopped to obtain a second charging and discharging time.

Wherein, before the step of controlling the second control end of the wireless control chip to output a high level to charge the capacitor through the thermistor and start timing, the method further includes: configuring the second control end to be an output mode, the first control end and The third control terminal is an input mode; the second control terminal of the control wireless control chip outputs a low level and maintains a second predetermined time.

Wherein, setting a plurality of sample temperatures in the reference thermostat time division, so that the thermistor is in the sample temperature, The wireless control chip acquires a second time ratio corresponding to the sample temperature, which is recorded as a sample time ratio, wherein a plurality of sample temperatures and corresponding sample time ratios form a sample database.

In order to solve the above technical problem, another technical solution adopted by the present invention is to provide a control method for an electronic thermometer, the control method comprising: controlling a reference resistor and a capacitor through a first control terminal of the wireless control chip to output a high and low level. Performing a charge and discharge operation to obtain a first charge and discharge time; and outputting a high and low level control thermistor and a capacitor through a second control terminal of the wireless control chip to perform a charge and discharge operation to obtain a second charge corresponding to the first charge and discharge time a discharge time; performing a predetermined number of repeated operations on the two steps to obtain a plurality of first charge and discharge times and a second charge and discharge time; obtaining a ratio of each of the first charge and discharge times to a corresponding second charge and discharge time, recorded as a third time ratio; obtaining an average value of each third time ratio, recorded as a first mean value; obtaining an absolute value of a difference between each third time ratio and the first mean value, which is recorded as a first absolute value; deleting the first absolute value is not a first time period corresponding to the third time ratio in the first predetermined range and a second charge and discharge time; obtaining an average value of each of the first charge and discharge times, a second average value; obtaining an absolute value of a difference between each of the first charging and discharging time and the second average value, and recording the second absolute value; deleting the first charging and discharging time in which the second absolute value is not within the second predetermined range and the corresponding The second charging and discharging time; obtaining the average value of each second charging and discharging time, which is recorded as the third mean value; obtaining the absolute value of the difference between each second charging and discharging time and the third mean value, which is recorded as the third absolute value; deleting the third absolute value a second charging/discharging time in which the value is not within the third predetermined range and a corresponding first charging and discharging time; obtaining a ratio of each of the first charging and discharging time to a corresponding second charging and discharging time, and recording the first time ratio; acquiring each The mean of the time ratio is recorded as the second time ratio; the second time ratio is matched in the sample database to obtain the temperature around the thermistor, wherein the sample database includes the sample temperature and the sample time ratio corresponding to the sample temperature.

Wherein, before the step of controlling the first control end of the wireless control chip to output a high level to charge the capacitor through the reference resistor and start timing, the method further includes: configuring the first control end to be an output mode, the second control end, and the third The control terminal is in an input mode; the first control terminal of the control wireless control chip outputs a low level and maintains the first predetermined time.

Wherein, before the step of controlling the second control end of the wireless control chip to output a high level to charge the capacitor through the thermistor and start timing, the method further comprises: configuring the second control end to be an output mode, the first control end and the first The third control terminal is an input mode; the second control terminal of the control wireless control chip outputs a low level and maintains a second predetermined time.

Wherein, the plurality of sample temperatures are set in the reference thermostat, so that the thermistor is in the sample temperature, and the wireless control chip acquires the second time ratio corresponding to the sample temperature, which is recorded as the sample time ratio, wherein the plurality of sample temperatures and The corresponding sample time ratio forms a sample database.

The invention has the beneficial effects that the electronic thermometer and the control method thereof of the invention pass the first control terminal of the wireless control chip to output the high and low level control reference resistors and capacitors for charging and discharging operations to obtain the first charging and discharging time; The second control terminal time-sharing output high and low level control the thermistor and the capacitor performs a charge and discharge operation to obtain a second charge and discharge time corresponding to the first charge and discharge time; and repeats the above two steps by a predetermined number of times to obtain more a first charging and discharging time and a second charging and discharging time; obtaining a ratio of each first charging and discharging time to a corresponding second charging and discharging value, and obtaining an average value of each ratio, which is recorded as a second time ratio; The two time ratios are matched to obtain the temperature around the thermistor. In the above manner, the electronic thermometer of the present invention can measure temperature without using an analog-to-digital converter and a voltage regulator, and consumes less power. At the same time, using the ratio of the first charge and discharge time to the second charge and discharge time Measuring the temperature eliminates many error factors and allows for a more accurate measurement of the temperature.

[Description of the Drawings]

1 is a schematic diagram showing the circuit structure of an electronic thermometer according to an embodiment of the present invention;

2 is a flow chart showing a method of controlling an electronic thermometer according to a first embodiment of the present invention;

Figure 3 is a flow chart of obtaining the first charge and discharge time in Figure 2;

Figure 4 is a flow chart of obtaining the second charge and discharge time in Figure 2;

Figure 5 is a waveform diagram of capacitor charging and discharging in Figures 3 and 4;

Figure 6 is a flow chart showing the temperature around the thermistor of Figure 2;

7 is a flow chart showing a method of controlling an electronic thermometer according to a second embodiment of the present invention;

Figure 8 is a flow chart showing a method of controlling an electronic thermometer according to a third embodiment of the present invention;

Fig. 9 is a flow chart showing a method of controlling an electronic thermometer according to a fourth embodiment of the present invention.

【detailed description】

Certain terms are used throughout the description and the claims to refer to the particular embodiments. It will be understood by those skilled in the art that the <RTIgt; The present specification and claims do not use the difference in names as a means of distinguishing components, but rather as a basis for distinguishing between functional differences of components. The invention will now be described in detail in conjunction with the drawings and embodiments.

1 is a schematic view showing the circuit structure of an electronic thermometer according to an embodiment of the present invention. As shown in FIG. 1, the electronic thermometer includes a wireless control chip 1, a reference resistor 2, a thermistor 3, a capacitor 4, an antenna 5, a battery 6, and a switch 7. The wireless control chip 4 includes a first control terminal PIO1, a second control terminal PIO2, and a third control terminal PIO3.

The first control terminal PIO1 of the wireless control chip 1 is connected to one end of the reference resistor 2, the second control terminal PIO2 is connected to one end of the thermistor 3, the other end of the reference resistor 2, the other end of the thermistor 3 and the capacitor 4 One end is connected, the other end of the capacitor 4 is grounded, and the third control terminal PIO3 is connected to the common node of the reference resistor 2, the thermistor 3 and the capacitor 4.

The wireless control chip 4 performs charging and discharging operations by alternately controlling the reference resistor 2 and the capacitor 4, and charging and discharging operations of the thermistor 3 and the capacitor 4 to obtain the temperature around the thermistor.

Preferably, the electronic thermometer further comprises an antenna 5, and the antenna 5 is connected to the wireless control chip 1 for wirelessly transmitting the temperature obtained by the wireless control chip 1.

Preferably, the electronic thermometer further comprises a battery 6 and a switch 7, which is connected to the wireless control chip 4 via a switch 7. The operation of powering on or off the wireless control chip 4 is controlled by the opening or closing of the switch 7. In other words, the on/off of the electronic thermometer can be realized by the opening or closing of the switch 7.

2 is a flow chart showing a method of controlling an electronic thermometer according to a first embodiment of the present invention, which is based on the electronic thermometer shown in FIG. 1. It should be noted that the method of the present invention is not limited to the sequence of the flow shown in FIG. 2 if substantially the same result is obtained. As shown in FIG. 2, the method includes the following steps:

Step S10: performing a charge and discharge operation by the first control terminal of the wireless control chip to output a high and low level control reference resistor and a capacitor to obtain a first charge and discharge time.

In step S10, the first control terminal of the wireless control chip outputs a high and low level control reference resistor and a capacitor to generate a reference charge and discharge process, and performs reference timing to obtain a reference charge and discharge time, that is, a first charge and discharge time. .

Please refer to FIG. 3 together. FIG. 3 is a flow chart of obtaining the first charging and discharging time in FIG. 2. As shown in FIG. 3, the steps of obtaining the first charging and discharging time include:

Step S101: The first control terminal, the second control terminal, and the third control terminal of the wireless control chip are configured to be in a no-pull mode.

In step S101, since the first control terminal, the second control terminal, and the third of the wireless control chip are GPIO (General Purpose Input Output), the usage mode of the wireless control chip needs to be configured before use. In this embodiment, it is configured in a pullless mode.

Step S102: configuring the first control end to be an output mode, and the second control end and the third control end are an input mode.

In step S102, configuring the first control terminal to be an output mode to apply or remove power to the reference resistor The voltage is such that the RC integrating circuit composed of the reference resistor and the capacitor realizes a charge and discharge operation. The third control terminal is configured to be in an input mode to detect the voltage across the capacitor during charging and discharging.

Step S103: Control the first control terminal to output a low level and maintain the first predetermined time.

In step S103, before the first charging and discharging time is acquired, the first control terminal is controlled to output a low level and maintained for a first predetermined time, so that the stored charge on the capacitor is completely released, thereby ensuring acquisition of the first charging and discharging time. The accuracy. After the first predetermined time, the voltage across the capacitor is close to zero volts, and the logic level of the third control terminal acquired by the wireless control chip is low.

A person skilled in the art can understand that the third control terminal is a general-purpose input/output port. When the third control terminal is configured as an input mode, when the input voltage value is greater than VIH, the wireless control chip reads the third. The logic level of the control terminal is high level. When the input voltage value is less than VIL, the read logic level is low level, wherein VIL is less than VIH, VIL and VIH specific values are selected by the selected wireless control chip. to make sure.

Step S104: Control the first control terminal to output a high level to charge the capacitor through the reference resistor and start timing.

In step S104, the timing is started while the first control terminal outputs the high level signal, that is, the start time of the first charging and discharging time, that is, the starting time at which the first control terminal outputs the high level signal.

After the first control terminal outputs a high level signal, that is, after applying a voltage to the reference resistor, the capacitor starts to charge, and the voltage across the capacitor rises exponentially. Wherein, as the voltage across the capacitor gradually rises from near zero volts, when the voltage rises to VIH, the logic level of the third control terminal obtained by the wireless control chip changes from a low level to a high level.

Step S105: When the wireless control chip detects that the third control terminal is at a high level, the first control terminal is controlled to output a low level to discharge the capacitor through the reference resistor.

In step S105, when the wireless control chip detects that the third control terminal is at a high level, the first control terminal outputs a low level signal to cause the capacitor to start discharging, and the voltage across the capacitor decreases exponentially. As the voltage across the capacitor decreases, when the voltage drops to VIL, the logic level of the third control terminal read by the wireless control chip changes from a high level to a low level.

Step S106: When the wireless control chip detects that the third control terminal changes from a high level to a low level, the timing is stopped to obtain a first charging and discharging time.

In step S106, when the wireless control chip detects that the third control terminal changes from a high level to a low level, the timing is stopped, that is, the end time of the first charging and discharging time, that is, the time when the capacitor is discharged until the voltage becomes VIL. . In the present embodiment, the logic level of the digital circuit is directly used as the criterion of the time point, and the comparator of the analog circuit is not used as the criterion of the time point, so that the circuit of the electronic thermometer is simpler, and the electronic thermometer is further reduced. Cost and power consumption.

In addition, the first charging and discharging time includes both the charging time of the capacitor and the discharging time of the capacitor, and has higher resolution and temperature accuracy than the method of calculating the temperature using only the charging time or only using the discharging time. high.

Step S11: The second control terminal of the wireless control chip outputs a high and low level control the thermistor and the capacitor to perform a charge and discharge operation to obtain a second charge and discharge time corresponding to the first charge and discharge time.

In step S11, the second control terminal of the wireless control chip outputs a high and low level control the thermistor and the capacitor to generate a measured charging and discharging process, and performs measurement timing to obtain a measured charging and discharging time, that is, a second charging and discharging. time.

Please refer to FIG. 4 together. FIG. 4 is a flow chart of obtaining the second charging and discharging time in FIG. 2. As shown in FIG. 4, the step of acquiring the second charging and discharging time includes:

Step S111: The second control terminal is configured to be in an output mode, and the first control terminal and the third control terminal are in an input mode.

Step S112: Control the second control terminal to output a low level and maintain the second predetermined time.

Step S113: Control the second control terminal to output a high level to charge the capacitor through the thermistor and start timing.

Step S114: When the wireless control chip detects that the third control terminal is at a high level, the second control terminal is controlled to output a low level to discharge the capacitor through the thermistor.

Step S115: When the wireless control chip detects that the third control terminal changes from a high level to a low level, the timing is stopped to obtain a second charging and discharging time.

The step of acquiring the second charging and discharging time shown in FIG. 4 is similar to the step of acquiring the first charging and discharging time shown in FIG. 3, and the main difference is that: in FIG. 4, the second control terminal is applied to the thermistor or The voltage is removed, so that the RC integrating circuit composed of the thermistor and the capacitor realizes the charging and discharging operation. In FIG. 3, a voltage is applied or removed to the reference resistor through the first control terminal, so that the RC integration circuit composed of the reference resistor and the capacitor realizes a charge and discharge operation. The second predetermined time in FIG. 4 and the first predetermined time in FIG. 3 may be the same or different.

In addition, in the present embodiment, when the execution of step S106 is completed, step S111 is started.

Please refer to FIG. 5 together. FIG. 5 is a waveform diagram of capacitor charging and discharging in FIG. 3 and FIG. As shown in FIG. 5, the T axis represents time and the V axis represents voltage.

Wherein, TREST1 is a first predetermined time for the first control terminal to output a low level, and TREST2 is a second predetermined time for the second control terminal to output a low level, TREF is a first charging and discharging time, and TMEA is a second charging and discharging time.

Wherein, the voltage VOL corresponds to the output low level of the first control terminal or the second control terminal, which is close to zero volt; the voltage VIH corresponds to the minimum voltage value of the logic high level of the third control terminal, that is, the input high voltage of the third control terminal The voltage VIL corresponds to the maximum voltage value of the logic low level of the third control terminal, that is, the input low level of the third control terminal.

Step S12: performing a predetermined number of repeated operations on the above two steps to obtain a plurality of first charging and discharging times and second charging and discharging times.

In step S12, after performing a predetermined number of repetition operations on steps S10 and S11, since a set of first charge and discharge times and a second charge and discharge time are obtained every time steps S10 and S11 are performed, a predetermined number of steps S10 and After the repeated operation of step S11, a first number of sets of first charge and discharge times and a second charge and discharge time are obtained.

Step S13: Obtain a ratio of each first charging and discharging time to a corresponding second charging and discharging time, and record the first time ratio.

In step S13, a ratio operation, that is, a division operation, is performed on each of the first charge and discharge times and the corresponding second charge and discharge time, respectively, to obtain a plurality of first time ratios.

In the present embodiment, preferably, in order to eliminate the real number operation, an integer operation is used, and the calculated first time ratio is subjected to the amplification operation and then the subsequent operation is performed. The magnification of the first time ratio is determined according to the requirements of the body temperature accuracy. For example, when the magnification is 10000 times, the corresponding low temperature error is 0.004 ° C, and the high temperature error is 0.002 ° C.

Step S14: Acquire an average value of each first time ratio, and record it as a second time ratio.

In step S14, the second time ratio is the average of the first time ratio after 10,000 times magnification. It should be understood by those skilled in the art that the multiple of the magnification is 10000 times, which is only an example, and the invention is not limited thereto.

Step S15: Matching the second time ratio in the sample database to obtain the temperature around the thermistor, wherein the sample database includes the sample temperature and a sample time ratio corresponding to the sample temperature.

In step S15, the second time ratio is first matched in the sample database to obtain a sample time ratio corresponding to the second time ratio, and then the corresponding sample temperature is obtained in the sample database according to the sample time ratio, and finally calculated according to the sample temperature. The temperature around the thermistor.

Specifically, the temperature around the thermistor can be obtained according to the following formula:

100t = 100 (10000k - 10000kn) / (10000k (n + 1) - 10000kn) + 100tn.

In combination with the above formula, and please refer to FIG. 6 together, FIG. 6 is a flow chart of obtaining the temperature around the thermistor in FIG. As shown in FIG. 6, the steps of obtaining the temperature around the thermistor include:

Step S151: Obtain two sample time ratios adjacent to the second time ratio in the sample database, and record the first sample time ratio and the second sample time ratio.

In step S151, comparing the second time ratio 10000k with the sample time ratio in the sample time library, obtaining the two sample time ratios closest to the second time ratio, respectively recorded as the first sample time ratio 10000kn and the first The second sample time ratio is 10000 k(n+1), the first sample time ratio is 10000 kn is smaller than the second time ratio 10000 k, and the second time ratio 10000 k is smaller than the second sample time ratio 10000 k (n+1). Wherein, preferably, the sample time ratio stored in the sample database is 10,000 times the sample time ratio after the amplification.

Step S152: Acquire a difference between the second time ratio and the first sample time ratio, and record it as the first difference value.

In step S152, the first difference is (10000k - 10000kn).

Step S153: Acquire a difference between the time ratio of the second sample and the time ratio of the first sample, and record it as the second difference.

In step S153, the second difference is (10000k(n+1) - 10000kn).

Step S154: The temperature around the thermistor is obtained by summing the ratio of the first difference value to the second difference value and the sample temperature corresponding to the first sample time ratio.

In step S154, first, a ratio of the first difference value to the second difference value is calculated, that is, (10000k-10000kn)/(10000k(n+1)-10000kn), and then the ratio is corresponding to the first sample time 10000kn. The sample temperature tn is summed to obtain the temperature t around the thermistor, that is, t = (10000k - 10000kn) / (10000k (n + 1) - 10000kn) + tn.

Preferably, in order to eliminate the real number operation, an integer operation is used, and the calculated ratio of the first difference value to the second difference value is subjected to an amplification operation, and then a subsequent summation operation is performed.

In this embodiment, the magnification of the ratio of the first difference value to the second difference value is 100 times, and the sample temperature stored in the sample database is the sample temperature 100tn after performing 100 times magnification, and therefore, the heat after being amplified by 100 times The temperature around the sensitive resistor is 100t=100 (10000k-10000kn)/(10000k(n+1)-10000kn)+100tn.

In other embodiments, obtaining the temperature around the thermistor can also be performed by looking up the closest sample time ratio in the sample time library, using the closest sample time ratio corresponding to the sample temperature as the temperature around the thermistor, This way, you can simplify the process of calculation and increase the speed of calculation.

Fig. 7 is a flow chart showing a method of controlling an electronic thermometer according to a second embodiment of the present invention, which is based on the electronic thermometer shown in Fig. 1. It should be noted that the method of the present invention is not limited to the sequence of processes shown in FIG. 7 if substantially the same result is obtained.

As shown in FIG. 7, the main differences between the first embodiment in FIG. 7 and FIG. 2 are as follows:

After step S13, FIG. 7 further includes the following steps:

Step S701: Acquire a ratio of each first charging and discharging time to a corresponding second charging and discharging time, and record it as a third time ratio.

In step S701, the third time ratio is a third time ratio after performing the amplification operation, and the amplification factor is specifically 10000 times.

Step S702: Acquire an average value of each third time ratio, and record it as a first average value.

In step S702, the first mean value is an average value of each of the third time ratios after the magnification is 10000 times.

Step S703: Acquire an absolute value of the difference between each third time ratio and the first mean value, and record it as the first absolute value.

Step S704: Delete the first charging and discharging time and the second charging and discharging time corresponding to the third time ratio in which the first absolute value is not within the first predetermined range.

In step S704, the first predetermined range is determined according to the requirements of the body temperature accuracy. In this embodiment, the first predetermined range is less than or equal to 100, that is, if the first absolute value exceeds 100, the first charging and discharging time corresponding to the first absolute value and the second charging and discharging time are deleted. When the first predetermined range is less than or equal to 100, the error is 0.4 ° C corresponding to the low temperature, and 0.2 ° C when the temperature is high.

It can be understood by those skilled in the art that after performing steps S701 to S704, the first charging and discharging time and the second charging and discharging time corresponding to the ratio of the first charging and discharging time and the second charging and discharging time including the coarse error can be eliminated. Therefore, the fluctuation of the result caused by the random interference can be reduced, the accuracy of the subsequent calculation time ratio can be improved, and the accuracy of calculating the temperature around the thermistor can be further improved.

The other steps of the flow chart shown in FIG. 7 have been disclosed in FIG. 2, and for brevity, no further details are provided herein.

Fig. 8 is a flow chart showing a method of controlling an electronic thermometer according to a third embodiment of the present invention, which is based on the electronic thermometer shown in Fig. 1. It should be noted that if there are substantially the same results, the method of the present invention is not limited to the sequence of processes shown in FIG.

As shown in FIG. 8, the main difference between the first embodiment in FIG. 8 and FIG. 2 is as follows:

After step S13, FIG. 8 further includes the following steps:

Step S801: Acquire an average value of each first charging and discharging time, and record it as a second average value.

Step S802: Acquire an absolute value of a difference between each first charging and discharging time and a second average value, and record it as a second absolute value.

Step S803: Delete the first charging and discharging time in which the second absolute value is not within the second predetermined range and the corresponding second charging and discharging time.

In step S803, the second predetermined range is determined according to the requirements of the body temperature accuracy. In this embodiment The second predetermined range is less than or equal to 50 microseconds, that is, if the second absolute value exceeds 50 microseconds, the first charging and discharging time and the corresponding second charging and discharging time are deleted. Wherein when the second predetermined range is less than or equal to 50 microseconds, the error is 0.25° C. at the low temperature and 0.6° C. at the high temperature.

It can be understood by those skilled in the art that after performing steps S801 to S803, the first charging and discharging time containing the coarse error and the corresponding second charging and discharging time can be eliminated, thereby reducing the fluctuation of the result caused by the random interference and improving the subsequent calculation. The accuracy of the time ratio further improves the accuracy of calculating the temperature around the thermistor.

The other steps of the flow chart shown in FIG. 8 have been disclosed in FIG. 2, and for brevity, no further details are provided herein.

Fig. 9 is a flow chart showing a method of controlling an electronic thermometer according to a fourth embodiment of the present invention, which is based on the electronic thermometer shown in Fig. 1. It should be noted that if there are substantially the same results, the method of the present invention is not limited to the sequence of processes shown in FIG.

As shown in FIG. 9, the main difference between the first embodiment in FIG. 9 and FIG. 2 is as follows:

After step S13, FIG. 9 further includes the following steps:

Step S901: Acquire an average value of each second charging and discharging time, and record it as a third average value.

Step S902: Acquire an absolute value of a difference between each second charging and discharging time and a third average value, and record it as a third absolute value.

Step S903: deleting the second charging and discharging time in which the third absolute value is not within the third predetermined range and the corresponding first charging and discharging time.

In step S903, the third predetermined range is determined according to the requirements of the body temperature accuracy. In this embodiment, the third predetermined range is less than or equal to 50 microseconds, that is, if the third absolute value exceeds 50 microseconds, the second charging and discharging time and the corresponding first charging and discharging time are deleted. Wherein when the third predetermined range is less than or equal to 50 microseconds, the error is 0.25 ° C corresponding to low temperature and 0.6 ° C at high temperature.

It can be understood by those skilled in the art that after performing steps S901 to S903, the second charging and discharging time including the coarse error and the corresponding first charging and discharging time can be eliminated, thereby reducing the fluctuation of the result caused by the random interference and improving the subsequent calculation. Time ratio accuracy, further improve the calculation of the thermistor week The accuracy of the temperature of the side.

The other steps of the flow chart shown in FIG. 9 have been disclosed in FIG. 2, and for brevity, no further details are provided herein.

Fig. 10 is a flow chart showing a method of controlling an electronic thermometer according to a fourth embodiment of the present invention, which is based on the electronic thermometer shown in Fig. 1. It should be noted that if there are substantially the same results, the method of the present invention is not limited to the sequence of processes shown in FIG.

As shown in FIG. 10, the main differences between the first embodiment in FIG. 10 and FIG. 2 are as follows:

After step S13, FIG. 10 further includes the following steps:

Step S1001: Obtain a ratio of the first charging and discharging time to the corresponding second charging and discharging time, and record it as a third time ratio;

Step S1002: Acquire an average value of each third time ratio, and record it as a first mean value;

Step S1003: Acquire an absolute value of a difference between each third time ratio and a first mean value, and record it as a first absolute value;

Step S1004: Delete the first charging and discharging time and the second charging and discharging time corresponding to the third time ratio in which the first absolute value is not within the first predetermined range.

Step S1005: Obtain an average value of each first charging and discharging time, and record it as a second average value;

Step S1006: Obtain an absolute value of a difference between each first charging and discharging time and a second average value, and record it as a second absolute value;

Step S1007: deleting the first charging and discharging time in which the second absolute value is not within the second predetermined range and the corresponding second charging and discharging time.

Step S1008: Acquire an average value of each second charging and discharging time, and record it as a third average value;

Step S1009: Obtain an absolute value of a difference between each second charging and discharging time and a third average value, and record it as a third absolute value;

Step S1010: Delete the second charging and discharging time in which the third absolute value is not within the third predetermined range and the corresponding first charging and discharging time.

Those skilled in the art can understand that after performing steps S1001 to S1010, the content may be coarse. The first charging and discharging time and the second charging and discharging time corresponding to the ratio of the first charging/discharging time of the error to the second charging and discharging time, the first charging and discharging time including the coarse error, and the corresponding second charging and discharging time, and the coarse charging error The second charging and discharging time and the corresponding first charging and discharging time are all eliminated, thereby reducing the fluctuation of the result caused by the random interference, improving the accuracy of the subsequent calculation time ratio, and further improving the accuracy of calculating the body temperature around the thermistor.

In a practical application, since the temperature of the temperature around the thermistor obtained by the control method according to the fourth embodiment of the present invention is fast, in order to reduce the fluctuation of the result caused by the random interference, the control method in the fourth embodiment can be performed. The operation was repeated to obtain a plurality of temperatures, and then the plurality of temperatures were averaged and then measured as an electronic thermometer.

In addition, the sample time ratio and the corresponding sample temperature in the sample database of the present invention can also be obtained according to the control method of the first embodiment, the second embodiment, the third embodiment or the fourth embodiment of the present invention. Specifically, a plurality of sample temperatures are set with a reference thermostat to place the thermistor in the sample temperature. The wireless control chip first runs the control method in the first embodiment, the second embodiment, the third embodiment, or the fourth embodiment to obtain a second time ratio corresponding to the sample temperature, that is, a sample time ratio, and then the wireless control chip The sample time ratio and the corresponding sample temperature are stored in the sample database. Preferably, since the control method of the fourth embodiment has higher precision, in actual use, the wireless control chip operates the control method in the fourth embodiment to acquire the sample time ratio.

The above is only the embodiment of the present invention, and is not intended to limit the scope of the invention, and the equivalent structure or equivalent process transformations made by the description of the invention and the drawings are directly or indirectly applied to other related technologies. The fields are all included in the scope of patent protection of the present invention.

Claims

An electronic thermometer, wherein the electronic thermometer comprises a wireless control chip, a thermistor, a reference resistor and a capacitor;

The wireless control chip includes a first control end, a second control end, and a third control end;

The first control end is connected to one end of the reference resistor, the second control end is connected to one end of the thermistor, and the other end of the reference resistor and the other end of the thermistor are respectively One end of the capacitor is connected, the other end of the capacitor is grounded, and the third control end is connected to the reference resistor, the thermistor and the common node of the capacitor;

The wireless control chip performs a charge and discharge operation by alternately controlling the reference resistor and the capacitor, and performing charge and discharge operations on the thermistor and the capacitor to obtain a temperature around the thermistor.
The electronic clinical thermometer according to claim 1, wherein said electronic thermometer further comprises an antenna, said antenna being connected to said wireless control chip for said said periphery of said thermistor obtained by said wireless control chip The temperature is sent wirelessly.
The electronic clinical thermometer according to claim 2, wherein said electronic thermometer further comprises a battery and a switch, said battery being connected to said wireless control chip through said switch, wherein said switch is opened or closed to control said The wireless control chip is powered on or off.
A method of controlling an electronic thermometer according to claim 1, wherein the control method comprises:

Controlling the reference resistor and the capacitor to perform a charge and discharge operation by the first control terminal of the wireless control chip to output a high and low level to obtain a first charge and discharge time;

Controlling the thermistor and the capacitor to perform a charge and discharge operation by the second control terminal of the wireless control chip to output a high and low level to obtain a second charge and discharge time corresponding to the first charge and discharge time ;

Performing a predetermined number of repeated operations on the above two steps to obtain a plurality of the first charging and discharging times And the second charging and discharging time;

Obtaining a ratio of each of the first charging and discharging time to the corresponding second charging and discharging time, and recording the first time ratio;

Obtaining an average value of each of the first time ratios, and recording the second time ratio;

The second time ratio is matched in a sample database to obtain a temperature around the thermistor, wherein the sample database includes a sample temperature and a sample time ratio corresponding to the sample temperature.
The method of claim 4, wherein the step of matching the second time ratio in the sample database to obtain a temperature around the thermistor is specifically:

Obtaining, in the sample database, a time ratio of two samples adjacent to the second time ratio, which is recorded as a first sample time ratio and a second sample time ratio, wherein the first sample time ratio is smaller than the first Two sample time ratio;

Obtaining a difference between the second time ratio and the first sample time ratio, and recording the first difference;

Obtaining a difference between the second sample time ratio and the first sample time ratio, and recording the second difference;

The temperature around the thermistor is obtained by summing the ratio of the first difference value to the second difference value and the sample temperature corresponding to the first sample time ratio.
The method according to claim 4, wherein said step further comprises the step of: obtaining said ratio of said first charge and discharge time to said corresponding second charge and discharge time;

Obtaining a ratio of each of the first charging and discharging time to the corresponding second charging and discharging time, and recording the third time ratio;

Obtaining an average value of each of the third time ratios, and recording the first mean value;

Obtaining an absolute value of a difference between each of the third time ratio and the first mean value, and recording the first absolute value;

And deleting the first charging and discharging time and the second charging and discharging time that are the third time ratio in which the first absolute value is not within the first predetermined range.
The method according to claim 4, wherein said step further comprises the step of: obtaining said ratio of said first charge and discharge time to said corresponding second charge and discharge time;

Obtaining an average value of each of the first charging and discharging times, and recording the second average value;

Obtaining an absolute value of a difference between each of the first charging and discharging time and the second average value, which is recorded as a second absolute value;

The first charging and discharging time in which the second absolute value is not within the second predetermined range and the corresponding second charging and discharging time are deleted.
The method according to claim 4, wherein said step further comprises the step of: obtaining said ratio of said first charge and discharge time to said corresponding second charge and discharge time;

Obtaining an average value of each of the second charging and discharging times, and recording the third average value;

Obtaining an absolute value of a difference between each of the second charging and discharging time and the third mean value, and recording the third absolute value;

And deleting the second charging and discharging time in which the third absolute value is not within the third predetermined range and the corresponding first charging and discharging time.
The method according to claim 4, wherein said first control terminal of said wireless control chip outputs a high and low level to control said reference resistor and said capacitor to perform a charge and discharge operation to obtain a first charge The steps of the discharge time are specifically as follows:

Controlling the first control terminal of the wireless control chip to output a high level to charge the capacitor through the reference resistor and start timing;

When the wireless control chip detects that the third control terminal is at a high level, the first control terminal of the wireless control chip is controlled to output a low level to discharge the capacitor through the reference resistor;

When the wireless control chip detects that the third control terminal changes from a high level to a low level, the timing is stopped to obtain a first charging and discharging time.
The method according to claim 9, wherein said step of controlling said first control terminal of said wireless control chip to output a high level to charge said capacitor through said reference resistor and start timing is performed The method further includes:

Configuring the first control end to be an output mode, where the second control end and the third control end are Entry mode

The first control terminal controlling the wireless control chip outputs a low level and maintains a first predetermined time.
The method according to claim 4, wherein the step of controlling the thermistor and the capacitor to perform a charge and discharge operation to acquire a second charge and discharge time corresponding to the first charge and discharge time is specifically:

Controlling the second control terminal of the wireless control chip to output a high level to charge the capacitor through the thermistor and start timing;

When the wireless control chip detects that the third control terminal is at a high level, controlling the second control terminal of the wireless control chip to output a low level to discharge the capacitor through the thermistor;

When the wireless control chip detects that the third control terminal changes from a high level to a low level, the timing is stopped to obtain a second charging and discharging time.
The method of claim 11, wherein said step of controlling said second control terminal of said wireless control chip to output a high level to charge said capacitor through said thermistor and initiate timing is The method further includes:

Configuring the second control end to be an output mode, where the first control end and the third control end are input modes;

The second control terminal controlling the wireless control chip outputs a low level and maintains a second predetermined time.
The method according to claim 4, wherein a plurality of said sample temperatures are set in time with reference to a constant temperature bath such that said thermistor is in said sample temperature, and said wireless control chip acquires a position corresponding to said sample temperature The second time ratio is recorded as a sample time ratio, wherein a plurality of the sample temperatures and the corresponding sample time ratio form a sample database.
A method of controlling an electronic thermometer according to claim 1, wherein the control method comprises:

Controlling the reference resistor and the capacitor to perform a charge and discharge operation by the first control terminal of the wireless control chip to output a high and low level to obtain a first charge and discharge time;

Controlling the thermistor and the capacitor to perform a charge and discharge operation by the second control terminal of the wireless control chip to output a high and low level to obtain a second charge and discharge time corresponding to the first charge and discharge time ;

Performing a predetermined number of repeated operations on the above two steps to obtain a plurality of the first charging and discharging time and the second charging and discharging time;

Obtaining a ratio of each of the first charging and discharging time to the corresponding second charging and discharging time, and recording the third time ratio;

Obtaining an average value of each of the third time ratios, and recording the first mean value;

Obtaining an absolute value of a difference between each of the third time ratio and the first mean value, and recording the first absolute value;

Deleting the first charging and discharging time and the second charging and discharging time corresponding to the third time ratio in which the first absolute value is not within the first predetermined range;

Obtaining an average value of each of the first charging and discharging times, and recording the second average value;

Obtaining an absolute value of a difference between each of the first charging and discharging time and the second average value, which is recorded as a second absolute value;

Deleting the first charging and discharging time that the second absolute value is not within the second predetermined range and the corresponding second charging and discharging time;

Obtaining an average value of each of the second charging and discharging times, and recording the third average value;

Obtaining an absolute value of a difference between each of the second charging and discharging time and the third mean value, and recording the third absolute value;

Deleting the second charging and discharging time that the third absolute value is not within the third predetermined range and the corresponding first charging and discharging time;

Obtaining a ratio of each of the first charging and discharging time to the corresponding second charging and discharging time, and recording the first time ratio;

Obtaining an average value of each of the first time ratios, and recording the second time ratio;

The second time ratio is matched in a sample database to obtain a temperature around the thermistor, wherein the sample database includes a sample temperature and a sample time ratio corresponding to the sample temperature.
The method according to claim 14, wherein said first control terminal of said wireless control chip outputs a high and low level to control said reference resistor and said capacitor to perform a charge and discharge operation to obtain a first charge The steps of the discharge time are specifically as follows:

Controlling the first control terminal of the wireless control chip to output a high level to charge the capacitor through the reference resistor and start timing;

When the wireless control chip detects that the third control terminal is at a high level, the first control terminal of the wireless control chip is controlled to output a low level to discharge the capacitor through the reference resistor;

When the wireless control chip detects that the third control terminal changes from a high level to a low level, the timing is stopped to obtain a first charging and discharging time.
The method according to claim 15, wherein said step of controlling said first control terminal of said wireless control chip to output a high level to charge said capacitor through said reference resistor and start timing is performed The method further includes:

And configuring the first control end to be an output mode, where the second control end and the third control end are input modes;

The first control terminal controlling the wireless control chip outputs a low level and maintains a first predetermined time.
The method according to claim 14, wherein the step of controlling the thermistor and the capacitor to perform a charge and discharge operation to acquire a second charge and discharge time corresponding to the first charge and discharge time is specifically:

Controlling the second control terminal of the wireless control chip to output a high level to charge the capacitor through the thermistor and start timing;

Controlling the wireless control when the wireless control chip detects that the third control terminal is at a high level The second control terminal of the chip outputs a low level to discharge the capacitor through the thermistor;

When the wireless control chip detects that the third control terminal changes from a high level to a low level, the timing is stopped to obtain a second charging and discharging time.
The method of claim 17, wherein said step of controlling said second control terminal of said wireless control chip to output a high level to charge said capacitor through said thermistor and initiate timing is The method further includes:

Configuring the second control end to be an output mode, where the first control end and the third control end are input modes;

The second control terminal controlling the wireless control chip outputs a low level and maintains a second predetermined time.
The method according to claim 14, wherein a plurality of said sample temperatures are set in a reference thermostat time division such that said thermistor is in said sample temperature, and said wireless control chip acquires a position corresponding to said sample temperature The second time ratio is recorded as a sample time ratio, wherein a plurality of the sample temperatures and the corresponding sample time ratio form a sample database.