Thermal sensors and chips

Abstract

This invention discloses a thermal sensor, comprising: a bandgap circuit that outputs a temperature-dependent voltage; a two-phase voltage-to-frequency converter coupled to the bandgap circuit during a normal phase to perform voltage-to-frequency conversion based on the temperature-dependent voltage, and disconnected from the bandgap circuit during a coefficient truncation phase to perform voltage-to-frequency conversion based on a power supply voltage; and a frequency meter coupled to the two-phase voltage-to-frequency converter to calculate a temperature-dependent frequency corresponding to the normal phase of the two-phase voltage-to-frequency converter and a temperature-independent frequency corresponding to the coefficient truncation of the two-phase voltage-to-frequency converter, wherein the temperature-dependent frequency and the temperature-independent frequency are provided for temperature assessment to eliminate non-ideal coefficients.

Description

Technical Field

[0001] This invention relates to the field of electrical technology, and more particularly to a thermal sensor and chip. Background Technology

[0002] In electronic devices, such as modern mobile devices using fast application processors (APs), maximum operating speed is often limited by thermal limitations. Therefore, accurate temperature sensing is crucial for maximizing the operating speed of electronic devices. Typically, thermal sensors are placed within a chip. Aging of the resistors and capacitors in the thermal sensor can reduce the accuracy of temperature sensing. Alternatively, packaging stress can also alter the resistors and capacitors used in the thermal sensor, thus affecting temperature sensing.

[0003] Therefore, there is a need for a more accurate thermal sensor. Summary of the Invention

[0004] In view of this, the present invention provides a thermal sensor with higher accuracy.

[0005] According to a first aspect of the present invention, a thermal sensor is disclosed, comprising:

[0006] Bandgap circuit, output voltage that is temperature-dependent;

[0007] A two-phase voltage-to-frequency converter is coupled to the bandgap circuit during the normal phase to perform voltage-to-frequency conversion based on the temperature-dependent voltage, and disconnected from the bandgap circuit during the coefficient truncation phase to perform voltage-to-frequency conversion based on the power supply voltage.

[0008] Switched capacitor resistors, including capacitors; and

[0009] A frequency meter, coupled to the two-phase voltage-frequency converter, is used to calculate temperature-dependent frequencies corresponding to the normal phase of the two-phase voltage-frequency converter and temperature-independent frequencies corresponding to the coefficient cutoff of the two-phase voltage-frequency converter.

[0010] Specifically, by combining the temperature-dependent frequency and the temperature-independent frequency, the non-ideal coefficient caused by the capacitor of the switched capacitor resistor is eliminated.

[0011] According to a second aspect of the present invention, a thermal sensor is disclosed, comprising:

[0012] Bandgap circuit, output voltage that is temperature-dependent;

[0013] A two-phase voltage-to-frequency converter is coupled to the bandgap circuit during the normal phase to perform voltage-to-frequency conversion based on the temperature-dependent voltage, and disconnected from the bandgap circuit during the coefficient truncation phase to perform voltage-to-frequency conversion based on the power supply voltage.

[0014] Switched capacitors, resistors, and dividers; and

[0015] A frequency meter, coupled to the two-phase voltage-frequency converter, is used to calculate temperature-dependent frequencies corresponding to the normal phase of the two-phase voltage-frequency converter and temperature-independent frequencies corresponding to the coefficient cutoff of the two-phase voltage-frequency converter.

[0016] The switched capacitor resistor is modeled after a resistor based on the oscillation signal after passing through the divider.

[0017] According to a third aspect of the present invention, a chip is disclosed, comprising:

[0018] The thermal sensor as described above; and

[0019] The processor evaluates temperature data based on temperature-related frequencies and temperature-independent frequencies, and evaluates temperature values ​​based on said temperature data.

[0020] Specifically, when evaluating the temperature data, the processor uses the temperature-independent frequency to eliminate the non-ideal coefficient of the temperature-dependent frequency.

[0021] The thermal sensor of the present invention calculates a temperature-dependent frequency corresponding to the normal phase of the dual-phase voltage-frequency converter and a temperature-independent frequency corresponding to the coefficient cutoff of the dual-phase voltage-frequency converter. This allows for a convenient next step of temperature assessment to eliminate non-ideal coefficients based on the provided temperature-dependent and temperature-independent frequencies, thereby eliminating degradation caused by aging effects of electronic components or packaging stress and improving the accuracy of the temperature obtained by the thermal sensor. Attached Figure Description

[0022] Figure 1 A chip 100 having a thermal sensor 102 according to an exemplary embodiment of the present invention is depicted;

[0023] Figure 2 Details of a two-phase voltage-frequency converter 108 according to an exemplary embodiment of the present invention are depicted;

[0024] Figure 3 This is a flowchart illustrating the thermal sensing process of the thermal sensor 102 according to an exemplary embodiment of the present invention. Detailed Implementation

[0025] Certain terms are used throughout the following description and claims to refer to specific components. As those skilled in the art will understand, electronic device manufacturers may use different names to refer to components. This document is not intended to distinguish between components with different names but identical functions. In the following description and claims, the terms “comprising” and “including” are used in an open-ended manner and should therefore be interpreted as meaning “including, but not limited to…”. Similarly, the term “coupled” is intended to indicate an indirect or direct electrical connection. Thus, if one device is coupled to another device, the connection can be either a direct electrical connection or an indirect electrical connection via other devices and connectors.

[0026] Figure 1 A chip 100 having a thermal sensor 102 is depicted according to an exemplary embodiment of the present invention.

[0027] The thermal sensor (or temperature sensor) 102 employs a transistor-based design (instead of using resistors or ETFs (electrothermal filters)). Transistor-based designs are more robust for mass production, and the temperature coefficient model is more accurate at design time. The thermal sensor 102 includes a charge pump circuit 104, a bandgap circuit 106, a dual-phase voltage-to-frequency converter 108, and a frequency meter 110. The supply voltage VDD (e.g., approximately 0.5V, such as 0.568V) pumps to a higher potential level CPV (e.g., around 1.2V) to operate the bandgap circuit 106, thus providing greater headroom for the bandgap circuit 106. The bandgap circuit can also be referred to as a bandgap reference circuit.

[0028] The bandgap circuit 106 includes a transistor whose junction forward bias voltage VBE varies with junction temperature. The bandgap circuit 106 outputs a temperature-independent reference voltage VREF and a temperature-dependent voltage VBE / 2 (wherein the temperature-dependent voltage VBE / 2 can also be other values, such as 1.2VBE, 1.1VBE, or VBE / 3, etc.; in this embodiment, the temperature-dependent voltage VBE / 2 is merely an example. Furthermore, the temperature-independent reference voltage VREF can also be determined based on the value of the temperature-dependent voltage). That is, in this embodiment, for example, the bandgap circuit 106 may include a bipolar junction transistor, and the temperature-dependent voltage VBE / 2 can be half the voltage difference between the base and emitter of the bipolar junction transistor; of course, as mentioned above, it can also be 1.2VBE, 1.1VBE, or VBE / 3, etc. In the normal phase, the biphase voltage-to-frequency converter 108 performs voltage-to-frequency conversion based on a temperature-dependent voltage VBE / 2 and a temperature-independent voltage VREF. An oscillation signal Sosc is generated that oscillates at a temperature-dependent frequency F1 (because VREF is temperature-independent and VBE / 2 is temperature-dependent, the temperature coefficient (oscillation frequency F1) of the final oscillation signal Sosc is determined by VBE / 2).

[0029] In addition to the normal phase, this invention specifically provides a coefficient capturing phase. During the coefficient capturing phase, the two-phase voltage-to-frequency converter 108 is disconnected from the bandgap circuit 106. Therefore, unlike the normal phase, the two-phase voltage-to-frequency converter 108 performs voltage-to-frequency conversion based on the power supply voltage (e.g., VDD and VDD / 2, where VDD / 2 is merely illustrative and not limiting; other values ​​such as VDD / 3, 1.2VDD, etc. can also be used). The resulting oscillation signal Sosc is modified to oscillate at a temperature-independent frequency F1_Coeff. The temperature-independent frequency F1_Coeff is used to eliminate non-ideal coefficients. The coefficient capturing phase can also be referred to as the coefficient capturing phase or coefficient trapping phase.

[0030] Frequency counter 110 calculates a temperature-dependent frequency F1 and a temperature-independent frequency F1_Coeff. Frequency counter 110 can be a digital back-end of a transistor-based thermal sensor 102, and is coupled to a processor of chip 100. After calculating the temperature-dependent frequency F1 and the temperature-independent frequency F1_Coeff, frequency counter 110 can pass both frequencies together to processor 112. For example, during normal operation, frequency counter 110 first calculates the temperature-dependent frequency F1 and stores it in a register; then, during coefficient truncation, it calculates the temperature-independent frequency F1_Coeff and passes both frequencies together to processor 112. Processor 112 can derive a temperature-dependent period Period_1 from the temperature-dependent frequency F1 and a temperature-independent period Period_2 from the temperature-independent frequency F1_Coeff. The non-ideal coefficient of the temperature-dependent period Period_1 is shown in the temperature-independent period Period_2. The non-ideal coefficient of the temperature-dependent period Period_1 can be eliminated by dividing the temperature-dependent period Period_1 by the temperature-independent period Period_2. Furthermore, in another embodiment, after the frequency meter 110 transmits the temperature-dependent frequency F1 and the temperature-independent frequency F1_Coeff to the processor 112, the processor 112 directly uses the temperature-dependent frequency F1 and the temperature-independent frequency F1_Coeff for calculations (i.e., the processor 112 does not derive the temperature-dependent period Period_1 and the temperature-independent period Period_2, but directly uses, for example, F1 divided by F1_Coeff). In this way, the processor 112 does not need to convert the temperature-related frequency F1 and the temperature-independent frequency F1_Coeff into temperature-related periods Period_1 and Period_2 respectively (where the reciprocal of the temperature-related frequency F1 is the temperature-related frequency F1, and the reciprocal of the temperature-independent frequency F1_Coeff is the temperature-independent period Period_2). It can directly use the temperature-related frequency F1 and the temperature-independent frequency F1_Coeff to perform temperature evaluation to eliminate non-ideal coefficients (e.g., F1 divided by F1_Coeff). This saves calculation steps, allows for faster calculation and evaluation, and improves efficiency. In this embodiment, the evaluation (or estimation) can be a calculation, such as using mathematical steps or formulas.

[0031] In an exemplary embodiment, processor 112 evaluates temperature data x based on a temperature-dependent period Period_1 and a temperature-independent period Period_2 (or processor 112 evaluates temperature data x based on a temperature-dependent frequency F1 and a temperature-independent frequency F1_Coeff), and then evaluates temperature value T based on temperature data x. Because the non-ideal coefficient of the temperature-dependent period Period_1 can be eliminated by the temperature-independent period Period_2 during the evaluation of temperature data x (e.g., by dividing Period_1 by Period_2, or F1 by F1_Coeff), the temperature value Tx evaluated from the temperature data is reliable. Degradation of electronic components within thermal sensor 102 (e.g., degradation due to aging effects or packaging stress) does not affect the accuracy of thermal sensor 102. Based on the high-accuracy temperature value T, processor 112 can effectively optimize the operation or function of chip 100. Chip 100 with such a robust thermal sensor 102 can operate well in automotive electronics, thus ensuring a long service life for automotive electronics.

[0032] Figure 2 Details of a two-phase voltage-to-frequency converter 108 according to an exemplary embodiment of the present invention are depicted. The two-phase voltage-to-frequency converter 108 includes selection circuits 202 and 204 and a switched-capacitor integrator circuit 206. In a normal operation phase, selection circuits 202 and 204 pass a temperature-dependent voltage VBE / 2 and a temperature-independent voltage VREF to the switched-capacitor integrator circuit 206, and the switched-capacitor integrator circuit 206 generates an oscillation signal Sosc that oscillates at a temperature-dependent frequency F1. In a coefficient truncation phase, selection circuits 202 and 204 pass DC voltages VDD and VDD / 2 to the switched-capacitor integrator circuit 206, thereby generating an oscillation signal Sosc that oscillates at a temperature-independent frequency F1_Coeff.

[0033] The switched-capacitor integrator circuit 206 includes an integrator 208 (including a switched-capacitor resistor 210), a voltage-controlled oscillator (VCO) 212, and a divider 214. The switched-capacitor resistor 210 is coupled to the integrator 208 via its input terminal. When a temperature-independent reference voltage VREF is coupled to the reference terminal of the integrator 208 (the "+" terminal of the operational amplifier in the figure), the switched-capacitor resistor 210 receives a temperature-dependent voltage VBE / 2. When a DC voltage VDD / 2 is coupled to the reference terminal of the integrator 208, the switched-capacitor resistor 210 receives a DC voltage VDD. The VCO 212 generates an oscillation signal Sosc based on the output voltage of the integrator 208. The switched-capacitor resistor 210 can mimic a resistor, for example, by using the oscillation signal following the divider 214. The voltage-controlled oscillator 212 includes a resistor R1 connected to the output of the integrator 208, a transistor M3 connected to the gate of the transistor M3, and a capacitor C1 coupled between the resistor R1 and the transistor M3 (the other end of the capacitor C1 can be grounded). The transistor M3 (source or drain) is coupled to a voltage, for example, 0.568 volts (which can be freely set as needed).

[0034] As shown in the figure, the switched capacitor resistor 210 has switches 216 and 218 and a capacitor Cx. A divider 214 is coupled to the output of the voltage-controlled oscillator 212 and to switches 216 and 218 to control switches 216 and 218. Switches 216 and 218 are controlled by the output signal and inverted output signal of divider 214, respectively. The capacitor Cx has a first terminal for receiving a temperature-dependent voltage VBE / 2 or a DC voltage VDD, and a second terminal coupled to the input terminal (the "-" terminal of the operational amplifier in the figure) of integrator 208 via a second switch 218. Switch 216 is coupled between the first and second terminals of capacitor Cx. Integrator 208 also includes a capacitor Cc coupled between the input terminal (the "-" terminal of the operational amplifier in the figure) of integrator 208 and the output terminal of the operational amplifier.

[0035] according to Figure 2In the circuit design, both the temperature-dependent frequency F1 and the temperature-independent frequency F1_Coeff involve information about the capacitor Cx of the switched capacitor resistor 210, which may be affected by aging effects or packaging stress. By combining the temperature-dependent frequency F1 and the temperature-independent frequency F1_Coeff (e.g., dividing Period_1 by Period_2, or dividing F1 by F1_Coeff), the non-ideal coefficient caused by the capacitor Cx of the switched capacitor resistor 210 is eliminated. The temperature data x without the non-ideal coefficient is evaluated. Therefore, a high-precision temperature value T can be evaluated. The step of combining the temperature-dependent frequency F1 and the temperature-independent frequency F1_Coeff can be performed by a component other than the thermal sensor, such as a processor; while the thermal sensor provides the two frequencies mentioned above, thus providing the basis for the next step of combination or calculation. In a preferred embodiment, combining the temperature-related frequency F1 and the temperature-independent frequency F1_Coeff can be achieved by applying the temperature-related frequency F1 to the temperature-independent frequency F1_Coeff to eliminate Rx and Cx, i.e., to eliminate the influence of the variables Rx and Cx, thereby making the obtained temperature value more accurate.

[0036] During the normal phase, the temperature-related frequency F1 corresponds to the temperature-related period Period 1, Rx·Cx(VBE / 2VREF-1). That is... Of course, the temperature-dependent frequency F1 = 1 / Period_1. Due to aging effects or encapsulation stress, there may be undesirable changes in capacitor Cx. To capture the current value of capacitor Cx, the two-phase voltage-frequency converter 108 is switched to the coefficient capture stage.

[0037] During the coefficient truncation phase, the temperature-independent frequency F1_Coeff corresponds to the temperature-independent period Period_2, Rx·Cx. That is, Period_2 = Rx·Cx, and of course, the temperature-independent frequency F1_Coeff = 1 / Period_2. The temperature-independent period Period_2 carries information about the current value of the capacitor Cx.

[0038] The temperature-related frequency F1 and the temperature-independent frequency F1_Coeff, calculated by the frequency counter 110 and sent to the processor 112, can be converted by the processor 112 into Period_1 and Period_2. Alternatively, the processor 112 may not convert the temperature-related frequency F1 and the temperature-independent frequency F1_Coeff into Period_1 and Period_2 respectively, but instead directly use the temperature-related frequency F1 and the temperature-independent frequency F1_Coeff for evaluation or calculation to obtain temperature data x. As an example, in this embodiment, the processor 112 can further evaluate the temperature data x through the following calculations:

[0039]

[0040] Rx_cali, Cx_cali, VBE_cali, and VREF_cali are constants measured in the factory and etched into chip 100. The non-ideal coefficients Rx·Cx are perfectly eliminated in the evaluated temperature data x. Processor 112 can evaluate the temperature value T through the following calculation:

[0041] T = ax + b

[0042] Where a and b can be constants, a is the slope value, and b is the offset value. Based on high-precision temperature data x without non-ideal coefficients, the estimated temperature value T is accurate. Due to aging effects or encapsulation stress, considerable vibration or fluctuation may exist on the capacitor Cx within the switched capacitor resistor 206. In this invention, non-ideal vibration on the capacitor Cx does not affect the accuracy of the thermal sensor 102. Furthermore, when the processor directly uses the temperature-related frequency F1 and the temperature-independent frequency F1_Coeff for evaluation or calculation, a similar formula to the one described above can be used, simply rewriting Period_1 and Period_2 in the above formula as 1 / F1 and 1 / F1_Coeff respectively; the remaining calculations remain unchanged.

[0043] In some exemplary embodiments, the DC voltage delivered to the switched capacitor integrator circuit 206 is VDD and β·VDD. β is not limited to 1 / 2 and can be any constant, such as 1 / 3VDD, 1.2VDD, etc., as mentioned above. In this embodiment, the value is taken as 1 / 2 for easy calculation.

[0044] In another exemplary embodiment, a temperature-independent reference voltage VREF is not required. The disclosed biphase voltage-to-frequency converter is coupled to a bandgap circuit during the normal operating phase to perform voltage-to-frequency conversion based on a temperature-dependent voltage generated by the bandgap circuit (without considering the temperature-independent reference voltage VREF). The disclosed biphase voltage-to-frequency converter is disconnected from the bandgap circuit during the coefficient truncation phase to perform voltage-to-frequency conversion based on a single DC voltage derived from the supply voltage VDD.

[0045] Figure 3 This is a flowchart illustrating the thermal sensing process of the thermal sensor 102 according to an exemplary embodiment of the present invention.

[0046] In step S302, the biphase voltage-to-frequency converter 108 operates under normal conditions to perform voltage-to-frequency conversion based on a temperature-dependent voltage VBE / 2 and a temperature-independent reference voltage VREF. This generates an oscillation signal Sosc that oscillates at a temperature-dependent frequency F1.

[0047] In step S304, frequency meter 110 calculates the temperature-related frequency F1.

[0048] In step S306, the biphase voltage-to-frequency converter 108 operates during the coefficient truncation phase to perform voltage-to-frequency conversion based on two DC voltages, VDD and VDD / 2, and the resulting oscillations. The signal Sosc is switched to oscillate at a temperature-independent frequency F1_Coeff, which includes information about non-ideal coefficients.

[0049] In step S308, frequency meter 110 calculates the temperature-independent frequency F1_Coeff.

[0050] In step S310, processor 112 evaluates temperature data x based on a temperature-related frequency F1 (calculated from step S304) and a temperature-independent frequency F1_Coeff (calculated from step S308), and then evaluates temperature value T from temperature data x (e.g., T = ax + b), or evaluates or calculates temperature value T based on temperature data x.

[0051] In some exemplary embodiments, the thermal sensor 102 may be manufactured as a module to be fitted into any electronic device.

[0052] Those skilled in the art will readily observe that numerous modifications and alterations can be made to the apparatus and method while maintaining the teachings of this invention. Therefore, the foregoing disclosure should be interpreted as being limited only by the scope and limits of the appended claims.

Claims

1. A thermal sensor, characterized in that, include: Bandgap circuit, output voltage that is temperature-dependent; A two-phase voltage-to-frequency converter is coupled to the bandgap circuit during the normal phase to perform voltage-to-frequency conversion based on the temperature-dependent voltage, and disconnected from the bandgap circuit during the coefficient truncation phase to perform voltage-to-frequency conversion based on the power supply voltage. The two-phase voltage-frequency converter includes a switched capacitor integrator circuit, which comprises: An integrator comprising a switched capacitor resistor, the switched capacitor resistor comprising a capacitor having a first terminal for receiving a temperature-dependent voltage or a first DC voltage, and a second terminal having an input terminal coupled to the integrator via a second switch; A voltage-controlled oscillator generates an oscillation signal based on the output voltage of the integrator; and A divider, the divider being coupled between the output of the voltage-controlled oscillator and the switched capacitor resistor; The switched capacitor resistor is modeled as a resistor based on the oscillation signal after the divider; and A frequency meter, coupled to the two-phase voltage-frequency converter, is used to calculate temperature-dependent frequencies corresponding to the normal phase of the two-phase voltage-frequency converter and temperature-independent frequencies corresponding to the coefficient cutoff of the two-phase voltage-frequency converter. Specifically, by combining the temperature-related frequency and the temperature-independent frequency, the non-ideal coefficient caused by the capacitor of the switched capacitor resistor is eliminated; During the normal phase, the temperature-dependent voltage and the temperature-independent reference voltage are coupled to the switched-capacitor integrator circuit, and the switched-capacitor integrator circuit generates an oscillation signal that oscillates at the temperature-dependent frequency; and During the coefficient truncation phase, a first DC voltage and a second DC voltage obtained from the power supply voltage are coupled to the switched capacitor integrator circuit, thereby generating the oscillation signal by the switched capacitor integrator circuit at the temperature-independent frequency.

2. The thermal sensor as described in claim 1, characterized in that, Also includes: A charge pump circuit pumps the power supply voltage to a higher potential for operation of the bandgap circuit. The bandgap circuit also generates a temperature-independent reference voltage to be coupled to a biphase voltage-frequency converter having the temperature-dependent voltage.

3. The thermal sensor as described in claim 1, characterized in that, The switched capacitor integrator circuit include: The switched capacitor resistor is coupled to the integrator through the input terminal of the integrator. When the temperature-independent reference voltage is coupled to the reference terminal of the integrator, it receives the temperature-dependent voltage; when the temperature-independent reference voltage is coupled to the reference terminal of the integrator, it receives the first DC voltage.

4. The thermal sensor as described in claim 3, characterized in that, The switched capacitor resistor includes: The first switch and the second switch are controlled by the output signal and the inverted output signal of the divider, respectively; and The first switch is coupled between the first and second terminals of the capacitor.

5. The thermal sensor as described in claim 1 or 3, characterized in that: Both the temperature-related frequency and the temperature-independent frequency relate to information about the effects of aging or encapsulation stress on the capacitor of the switched capacitor resistor.

6. The thermal sensor as described in claim 4, characterized in that, The dual-phase voltage-frequency converter further includes: A first selection circuit couples the temperature-dependent voltage to a first terminal of the capacitor of the switched capacitor resistor during the normal operation phase, and couples the first DC voltage to the first terminal of the capacitor of the switched capacitor resistor during the coefficient cutoff phase; and The second selection circuit couples the temperature-independent reference voltage to the reference terminal of the integrator during the normal phase and couples the second DC voltage to the reference terminal of the integrator during the coefficient truncation phase.

7. The thermal sensor as described in claim 1, characterized in that, The bandgap circuit includes a bipolar junction transistor, and the temperature-dependent voltage is half the voltage difference between the base and emitter of the bipolar junction transistor.

8. The thermal sensor as described in claim 1, characterized in that: The second DC voltage is half of the first DC voltage.

9. A thermal sensor, characterized in that, include: Bandgap circuit, output voltage that is temperature-dependent; A two-phase voltage-to-frequency converter is coupled to the bandgap circuit during the normal phase to perform voltage-to-frequency conversion based on the temperature-dependent voltage, and disconnected from the bandgap circuit during the coefficient truncation phase to perform voltage-to-frequency conversion based on the power supply voltage. The two-phase voltage-frequency converter includes a switched capacitor integrator circuit, which comprises: Integrator, the integrator including a switched capacitor resistor; A voltage-controlled oscillator generates an oscillation signal based on the output voltage of the integrator; and A divider, the divider being coupled between the output of the voltage-controlled oscillator and the switched capacitor resistor; The switched capacitor resistor is modeled as a resistor based on the oscillation signal after the divider; and A frequency meter, coupled to the two-phase voltage-frequency converter, is used to calculate temperature-dependent frequencies corresponding to the normal phase of the two-phase voltage-frequency converter and temperature-independent frequencies corresponding to the coefficient cutoff of the two-phase voltage-frequency converter. The switched capacitor resistor is modeled as a resistor based on the oscillation signal after passing through the divider. During the normal phase, the temperature-dependent voltage and the temperature-independent reference voltage are coupled to the switched-capacitor integrator circuit, and the switched-capacitor integrator circuit generates an oscillation signal that oscillates at the temperature-dependent frequency; and During the coefficient truncation phase, a first DC voltage and a second DC voltage obtained from the power supply voltage are coupled to the switched capacitor integrator circuit, thereby generating the oscillation signal by the switched capacitor integrator circuit at the temperature-independent frequency.

10. A chip, characterized in that, include: The thermal sensor as described in any one of claims 1 to 9; as well as The processor evaluates temperature data based on temperature-related frequencies and temperature-independent frequencies, and evaluates a temperature value based on the temperature data, wherein the temperature-related frequencies and temperature-independent frequencies are transmitted to the processor together. Specifically, when evaluating the temperature data, the processor uses the temperature-independent frequency to eliminate the non-ideal coefficient of the temperature-dependent frequency.

11. The chip as described in claim 10, characterized in that: When evaluating the temperature data, the processor divides the temperature-related frequency by the temperature-independent frequency to eliminate non-ideal coefficients affected by the capacitor of the switched capacitor resistor.

12. The chip as described in claim 11, characterized in that: The processor evaluates the temperature value by performing the following calculations. T = ax + b, Where T is the temperature value, x is the temperature data, a is the slope value, and b is the offset value.

13. The chip as described in claim 10, characterized in that, The processor obtains a temperature-related period from the temperature-related frequency and a temperature-independent period from the temperature-independent frequency, to evaluate the temperature data based on the temperature-related period and the temperature-independent period, and to evaluate the temperature value based on the temperature data. Specifically, when evaluating the temperature data, the processor eliminates the non-ideal coefficient of the temperature-related period using the temperature-independent period.

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