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CN-122016066-A - Temperature sensor and electronic equipment

CN122016066ACN 122016066 ACN122016066 ACN 122016066ACN-122016066-A

Abstract

The application provides a temperature sensor and electronic equipment, and belongs to the technical field of electronic equipment. The temperature sensor comprises a temperature detection unit and an analog-to-digital conversion unit, wherein the temperature detection unit is connected with the analog-to-digital conversion unit, the analog-to-digital conversion unit comprises a successive approximation register SAR, the number of bits of the SAR is N, the number of the bits of the SAR is a positive integer greater than 8, the temperature detection unit is used for generating a reference voltage and a temperature detection voltage, outputting the reference voltage and the temperature detection voltage to the analog-to-digital conversion unit, the temperature detection voltage is positively correlated with the current detected temperature, the analog-to-digital conversion unit is used for adjusting the reference voltage for N times based on the temperature detection voltage, adjusting the numerical value of the SAR on the number of the N bits according to the sequence from high bits to low bits, and outputting the target numerical sequence. The temperature sensor of the application adopts a register with higher position, and the temperature accuracy of measurement is higher.

Inventors

  • JI YUAN

Assignees

  • 昀光微电子（上海）有限公司

Dates

Publication Date
20260512
Application Date
20260108

Claims (10)

  1. 1. The temperature sensor is characterized by comprising a temperature detection unit and an analog-to-digital conversion unit, wherein the temperature detection unit is connected with the analog-to-digital conversion unit, the analog-to-digital conversion unit comprises a successive approximation register SAR, the bit number of the SAR is N, and the N is a positive integer greater than 8; the temperature detection unit is used for generating a reference voltage and a temperature detection voltage, and outputting the reference voltage and the temperature detection voltage to the analog-to-digital conversion unit, wherein the temperature detection voltage is positively correlated with the current detected temperature; the analog-to-digital conversion unit is used for adjusting the reference voltage for N times based on the temperature detection voltage, adjusting the numerical values of the N digits of the SAR according to the sequence from high to low based on the magnitude relation between the reference voltage after the N times of adjustment and the temperature detection voltage, obtaining a target numerical value sequence and outputting the target numerical value sequence, wherein the target numerical value sequence is composed of the N numerical values of the SAR from high to low.
  2. 2. The temperature sensor of claim 1, wherein the temperature detection unit comprises a bandgap reference circuit, a subtracter, a first buffer, a second buffer and a third buffer, wherein a first output end of the bandgap reference circuit is connected with an input end of the first buffer, a second output end of the bandgap reference circuit is connected with an input end of the second buffer, a third output end of the bandgap reference voltage is connected with an input end of the third buffer, an output end of the first buffer is connected with a first input end of the subtracter, and an output end of the second buffer is connected with a second input end of the subtracter; The band gap reference circuit is used for generating positive temperature coefficient voltage, negative temperature coefficient voltage and reference voltage, and inputting the positive temperature coefficient voltage, the negative temperature coefficient voltage and the reference voltage into the first buffer, the second buffer and the third buffer respectively; the first buffer is used for buffering the positive temperature coefficient voltage to obtain buffered positive temperature coefficient voltage, and inputting the buffered positive temperature coefficient voltage into the subtracter; the second buffer is used for buffering the negative temperature coefficient voltage to obtain a buffered negative temperature coefficient voltage, and inputting the buffered negative temperature coefficient voltage into the subtracter; The subtracter is used for calculating the difference value between the buffered positive temperature coefficient voltage and the buffered negative temperature coefficient voltage to obtain the temperature detection voltage; and the third buffer is used for buffering the reference voltage to obtain the reference voltage.
  3. 3. The temperature sensor of claim 2, wherein the analog-to-digital conversion unit comprises a comparator, a digital-to-analog converter and a logic control module, wherein the SAR is positioned in the logic control module, the output end of the third buffer is connected with the first input end of the digital-to-analog converter, the output end of the subtracter and the output end of the digital-to-analog converter are respectively connected with the first input end and the second input end of the comparator, the output end of the comparator is connected with the input end of the logic control module, the first output end of the logic control module is connected with the second input end of the digital-to-analog converter, and the second output end of the logic control module is connected with an electronic element outside the temperature sensor; The subtracter is also used for inputting the temperature detection voltage into the comparator; the digital-to-analog converter is used for carrying out N times of adjustment on the reference voltage to obtain N times of adjusted reference voltage, and the N times of adjusted reference voltage is input into the comparator; The comparator is used for comparing the temperature detection voltage with the N times of adjusted reference voltages respectively to obtain N comparison results, and the N comparison results are input into the logic control module; The logic control module is used for adjusting the numerical value on the N digits of the SAR according to the sequence from the high order to the low order based on the N comparison results, obtaining the target numerical value sequence and outputting the target numerical value sequence.
  4. 4. The temperature sensor of claim 2, wherein the bandgap reference circuit is further configured to draw a positive compensation current from a positive feedback loop in which the positive temperature coefficient voltage is located that is less than a predetermined value, draw a negative compensation current from a negative feedback loop in which the negative temperature coefficient voltage is located that is less than a predetermined value, and compensate the reference voltage based on the positive compensation current and the negative compensation current.
  5. 5. The temperature sensor of claim 2, wherein the subtractor circuit comprises an operational amplifier, a first resistor, a second resistor, a third resistor, and a fourth resistor, the operational amplifier comprising a non-inverting input, an inverting input, and an output; The positive temperature coefficient voltage is input to the non-inverting input end of the operational amplifier through the first resistor, and the negative temperature coefficient voltage is input to the inverting input end of the operational amplifier through the third resistor; The second resistor is connected between the non-inverting input terminal and ground of the operational amplifier, and the fourth resistor is connected between the inverting input terminal and output terminal of the operational amplifier.
  6. 6. The temperature sensor according to claim 5, wherein the second resistor comprises a plurality of resistor units, each resistor unit is connected with a switch in parallel, and the resistance value of the circuit connected to the subtracter through the second resistor is adjusted by controlling the on-off of the parallel switch on the plurality of resistor units, so as to adjust the voltage value of the temperature detection voltage output by the subtracter.
  7. 7. The temperature sensor according to claim 5, wherein the fourth resistor comprises a plurality of resistor units, each resistor unit is connected with a switch in parallel, and the resistance value of the circuit of the subtractor connected with the fourth resistor is adjusted by controlling the on-off of the parallel switch on the plurality of resistor units so as to adjust the voltage value of the temperature detection voltage output by the subtractor.
  8. 8. A temperature sensor according to claim 3, wherein the input of the digital-to-analog converter is any one of the differential inputs inherent in the digital-to-analog converter.
  9. 9. The temperature sensor of claim 8, wherein the input of the digital-to-analog converter comprises a capacitor array and an equivalent capacitor, the equivalent capacitor being connected in series with the capacitor array, the capacitor array comprising a plurality of capacitors connected in parallel, the total capacitance of the capacitor array being the same as the capacitance of the equivalent capacitor.
  10. 10. An electronic device, characterized in that it comprises a temperature sensor according to any one of claims 1 to 9.

Description

Temperature sensor and electronic equipment Technical Field The present application relates to the field of electronic devices, and in particular, to a temperature sensor and an electronic device. Background The accuracy of the temperature sensor is critical to the stable operation of the display chip. The display chip can produce a large amount of heat when the during operation, if temperature control is inaccurate, probably leads to performance fluctuation, and the image shows unusually, even hardware damage. The high-precision detection capability of the temperature sensor can realize more timely and finer thermal management, and help the system to dynamically adjust the power consumption and the heat dissipation strategy, so that the display chip can be ensured to stably work for a long time in a high-efficiency state, and the energy efficiency ratio and the reliability of the display chip are improved. The accuracy of the current temperature sensor on the market is generally 8 bits, which means that the temperature sensor can only quantify the temperature change to 256 grades, so that the temperature sensor is difficult to capture fine temperature fluctuation in the whole temperature range, and can only achieve measurement accuracy of +/-1 ℃ or even lower. The coarse granularity detection capability cannot meet the control requirement of the display chip on the temperature, so that the system cannot respond to tiny temperature drift in time, the uniformity of brightness and the color accuracy are further affected, and the application of the system in the high-end precise display field is limited. Accordingly, it is desirable to provide a temperature sensor with high accuracy. Disclosure of Invention The embodiment of the application provides a temperature sensor and electronic equipment, wherein the temperature sensor adopts a higher-order register, and the measured temperature precision is higher. The technical scheme is as follows: In a first aspect, a temperature sensor, a temperature detection unit and an analog-to-digital conversion unit are provided, the temperature detection unit is connected with the analog-to-digital conversion unit, the analog-to-digital conversion unit comprises a SAR (Successive Approximation Register ), the number of bits of the SAR is N, and the N is a positive integer greater than 8; the temperature detection unit is used for generating a reference voltage and a temperature detection voltage, and outputting the reference voltage and the temperature detection voltage to the analog-to-digital conversion unit, wherein the temperature detection voltage is positively correlated with the current detected temperature; the analog-to-digital conversion unit is used for adjusting the reference voltage for N times based on the temperature detection voltage, adjusting the numerical values of the N digits of the SAR according to the sequence from high to low based on the magnitude relation between the reference voltage after the N times of adjustment and the temperature detection voltage, obtaining a target numerical value sequence and outputting the target numerical value sequence, wherein the target numerical value sequence is composed of the N numerical values of the SAR from high to low. In a second aspect, an electronic device is provided, the electronic device comprising the temperature sensor of the first aspect. The technical scheme provided by the embodiment of the application has the beneficial effects that: The temperature sensor provided by the embodiment of the application comprises a temperature detection unit and an analog-to-digital conversion unit. The analog-to-digital conversion unit comprises SAR, the bit number of the SAR is N, and N is a positive integer greater than 8. The temperature measuring process adopting the temperature sensor comprises the steps that a temperature detecting unit generates reference voltage and temperature detecting voltage, and the reference voltage and the temperature detecting voltage are output to an analog-to-digital converting unit. The analog-to-digital conversion unit adjusts the reference voltage for N times based on the temperature detection voltage, adjusts the values of the N digits of the SAR according to the sequence from the high order to the low order based on the magnitude relation between the reference voltage and the temperature detection voltage after the N times of adjustment, obtains a target value sequence and outputs the target value sequence, wherein the target value sequence is composed of the N digits of the SAR from the high order to the low order. The temperature detection voltage is positively correlated with the current detected temperature, and can reflect the temperature of the current environment. The number of adjustment times of the reference voltage is related to the number of bits of the SAR, the more the number of adjustment times of the reference voltage is, the more the reference voltage is, the t