A digital temperature conversion circuit, method, chip and electronic device

Abstract

The application provides a digital temperature conversion circuit, a method, a chip and an electronic device. The digital temperature conversion circuit comprises a frequency detection circuit, a voltage adjustment circuit and a digital temperature sensor circuit. The digital temperature sensor circuit is configured to generate a first clock signal according to an ambient temperature. The frequency detection circuit is configured to detect a frequency of the first clock signal and obtain curvature information of a curve of the frequency changing with the ambient temperature. The voltage adjustment circuit is configured to generate a first voltage signal according to the curvature information. The digital temperature sensor circuit is further configured to generate a second clock signal according to the ambient temperature and the first voltage signal, and convert the second clock signal into a digital code. The digital temperature conversion circuit improves the accuracy of temperature measurement.

Description

Technical Field

[0001] This application relates to the field of temperature sensing technology, and in particular to a digital temperature conversion circuit, method, chip, and electronic device. Background Technology

[0002] The advent of the digital age has made communication and daily life increasingly digital and intelligent, and electronic devices are ubiquitous. Sensors are indispensable components of electronic devices. To keep pace with the current global development, sensors are constantly evolving towards integration and digitalization. In recent years, semiconductor technology and integrated circuit processes have continued to develop to meet the demands for miniaturization and shorter response times in electronic devices. However, the shorter the response time of electronic devices, the more heat they generate. Therefore, monitoring the temperature of electronic devices is crucial for preventing malfunctions or damage.

[0003] With the development of semiconductor technology and integrated circuit process, temperature sensors have gradually evolved from analog to digital. However, due to the curvature on the output curve of the ring oscillator of existing digital temperature sensors, the temperature measurement accuracy of such digital temperature sensors is not high. Summary of the Invention

[0004] The purpose of this application is to provide a digital temperature conversion circuit, method, chip, and electronic device to solve the technical problem of low temperature measurement accuracy of existing digital temperature sensors.

[0005] In a first aspect, embodiments of this application provide a digital temperature conversion circuit, including a frequency detection circuit, a voltage regulation circuit, and a digital temperature sensor circuit;

[0006] A digital temperature sensor circuit is used to generate a first clock signal based on the ambient temperature.

[0007] The frequency detection circuit is used to detect the frequency of the first clock signal and obtain the curvature information of the frequency-temperature change curve.

[0008] A voltage regulation circuit is used to generate a first voltage signal based on curvature information;

[0009] The digital temperature sensor circuit also generates a second clock signal based on the ambient temperature and the first voltage signal, and converts the second clock signal into a digital code. This enables temperature measurement and improves the accuracy of temperature measurement.

[0010] Optionally, the voltage regulation circuit includes a curvature voltage regulation circuit and a voltage weighting circuit. The curvature voltage regulation circuit generates a second voltage signal based on curvature information, and the voltage weighting circuit weights the second voltage signal to obtain a first voltage signal. By generating the second voltage signal based on curvature information through the curvature voltage regulation circuit and weighting the second voltage signal through the voltage weighting circuit, a first voltage signal is obtained that acts on the digital temperature sensor circuit. This first voltage signal can precisely adjust the threshold voltage of the transistors in the digital temperature sensor circuit, thereby correcting the curvature of the output of the digital temperature sensor circuit and improving the temperature measurement accuracy of the digital temperature conversion circuit.

[0011] Optionally, the digital temperature sensor circuit includes:

[0012] A first ring oscillator is used to generate a second clock signal based on the ambient temperature and a first voltage signal;

[0013] A time amplifier is used to amplify the period of the second clock signal to obtain a second pulse signal;

[0014] A time converter is used to convert the second pulse signal into digital code.

[0015] A second clock signal is generated using a first ring oscillator based on the ambient temperature and a first voltage signal; the period of the second clock signal is amplified by a time amplifier to obtain a second pulse signal; the second pulse signal is converted into a digital code by a time converter; thus, the digital code related to the temperature can be accurately obtained.

[0016] Optionally, the first ring oscillator includes multiple delay units, at least one of which is connected to a voltage regulation circuit and receives a first voltage signal to adjust the delay duration of the delay unit according to the first voltage signal.

[0017] The ring oscillator generates two clock signals based on the delay duration of each delay unit.

[0018] The delay duration of the delay unit is adjusted by the first voltage signal. The ring oscillator obtains two clock signals based on the delay duration of each delay unit. The digital code about the temperature can then be accurately obtained through the second clock signal.

[0019] Optionally, the delay unit is an inverter, which includes an NMOS transistor and a PMOS transistor. The NMOS transistor and the PMOS transistor are respectively connected to a voltage regulation circuit to receive a first voltage signal. By having the NMOS transistor and the PMOS transistor respectively receive the first voltage signal, the frequency of the clock signal output by the first ring oscillator is adjusted.

[0020] Optionally, the substrates of the NMOS transistor and the PMOS transistor are respectively connected to a voltage regulation circuit. By having the NMOS transistor and the PMOS transistor receive a first voltage signal respectively, the voltage difference between the source and the substrate in the NMOS transistor and the PMOS transistor is adjusted, thereby adjusting the frequency of the clock signal output by the first ring oscillator.

[0021] Optionally, the time converter is also used to calculate the number of clock cycles of the second pulse signal using a standard clock and a counter, and to generate a digital code based on the number of clock cycles;

[0022] The digital temperature conversion circuit also includes digital circuitry, which calculates the ambient temperature value based on a digital code. The number of clock cycles for the second pulse signal is calculated using a standard clock and a counter, and a digital code is generated based on this clock cycle count. The ambient temperature value is then calculated from this digital code, allowing for the acquisition of an accurate ambient temperature reading.

[0023] Optionally, the digital temperature sensor circuit also includes:

[0024] A second ring oscillator is used to convert the ambient temperature into a first clock signal. By including a second ring oscillator in the digital temperature sensor circuit, the ambient temperature can be converted into a first clock signal, thus enabling temperature measurement and improving the accuracy of the temperature measurement.

[0025] Optionally, the first ring oscillator is also used for:

[0026] A first clock signal is generated based on the ambient temperature; and,

[0027] The frequency of the first clock signal is adjusted according to the first voltage signal to obtain the second clock signal.

[0028] Thirdly, embodiments of this application also provide a digital temperature conversion method, comprising the following steps:

[0029] A first clock signal is generated based on the ambient temperature;

[0030] The frequency of the first clock signal is detected, and the curvature information of the frequency-temperature change curve is obtained.

[0031] A first voltage signal is generated based on the curvature information;

[0032] A second clock signal is generated based on the ambient temperature and the first voltage signal, and then converted into a digital code. This enables temperature measurement and improves the accuracy of temperature measurement.

[0033] Optionally, generating a first voltage signal based on curvature information includes: generating a second voltage signal based on curvature information, and performing weighted processing on the second voltage signal to obtain the first voltage signal.

[0034] Optionally, generating a second clock signal based on the ambient temperature and the first voltage signal includes: obtaining a delay duration based on the first voltage signal, and obtaining the second clock signal based on the delay duration and the ambient temperature.

[0035] Optionally, the second clock signal is converted into a digital code, including: calculating the number of clock cycles of the second pulse signal using a standard clock and a counter, and generating a digital code based on the number of clock cycles.

[0036] Optionally, the digital temperature conversion method also includes: calculating the ambient temperature value based on the digital code.

[0037] Fourthly, embodiments of this application also provide a chip, including the digital temperature conversion circuit as described in any of the above technical solutions.

[0038] Fifthly, embodiments of this application also provide an electronic device, including the digital temperature conversion circuit or the chip described in any of the preceding claims.

[0039] This application provides a digital temperature conversion circuit, method, chip, and electronic device. A digital temperature sensor circuit generates a first clock signal based on the ambient temperature. A frequency detection circuit detects the frequency of the first clock signal and obtains the curvature information of the frequency-temperature change curve. A voltage adjustment circuit generates a first voltage signal based on the curvature information. The digital temperature sensor circuit generates a second clock signal based on the ambient temperature and the first voltage signal, and converts the second clock signal into a digital code. During temperature measurement, the digital temperature sensor circuit is calibrated based on the curvature of the frequency change of the first clock signal to generate a curvature-corrected second clock signal. The digital code corresponding to the second clock signal yields a more accurate temperature value, thereby improving the accuracy of temperature measurement. Attached Figure Description

[0040] Figure 1 This is a first circuit block diagram of the digital temperature conversion circuit according to an embodiment of this application;

[0041] Figure 2 This is a second circuit block diagram of the digital temperature conversion circuit according to an embodiment of this application;

[0042] Figure 3 This is a third circuit block diagram of the digital temperature conversion circuit according to an embodiment of this application;

[0043] Figure 4 This is a circuit schematic diagram of the first ring oscillator according to an embodiment of this application;

[0044] Figure 5 This is a fourth circuit block diagram of the digital temperature conversion circuit according to an embodiment of this application;

[0045] Figure 6 This is a fifth circuit block diagram of the digital temperature conversion circuit according to an embodiment of this application;

[0046] Figure 7 This is a sixth circuit block diagram of the digital temperature conversion circuit according to an embodiment of this application;

[0047] Figure 8 This is a flowchart illustrating the digital temperature conversion method according to an embodiment of this application.

[0048] Reference numerals: 100-Digital temperature conversion circuit; 111-First ring oscillator; 110-Digital temperature sensor circuit; 111-First ring oscillator; 112-Time amplifier; 113-Logic gate circuit; 114-Time converter; 115-Counter; 116-AND gate; 120-Frequency detection circuit; 130-Voltage regulation circuit; 131-Curvature voltage regulation circuit; 132-Voltage weighting circuit; 140-Second ring oscillator. Detailed Implementation

[0049] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0050] To enable those skilled in the art to better understand the solutions of this application, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0051] In the embodiments of this application, it should be noted that, in this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0052] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0053] In the description of the embodiments of this application, the words "example" or "for example" are used to indicate exemplification, illustration, or description. Any embodiment or design described as "example" or "for example" in the embodiments of this application is not to be construed as being more preferred or having more advantages than another embodiment or design. The use of the words "example" or "for example" is intended to present relative concepts in a clear manner.

[0054] Furthermore, in the embodiments of this application, "multiple" refers to two or more. Therefore, in the embodiments of this application, "multiple" can also be understood as "at least two". "At least one" can be understood as one or more, such as one, two, or more. For example, including at least one means including one, two, or more, and is not limited to which ones are included. For example, including at least one of A, B, and C, then it could include A, B, C, A and B, A and C, B and C, or A and B and C.

[0055] It should be noted that in the embodiments of this application, "connection" can be understood as electrical connection. The connection between two electrical components can be a direct or indirect connection between the two electrical components. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components.

[0056] Figure 1 This is a first circuit block diagram of a digital temperature conversion circuit according to an embodiment of this application. It should be noted that, if substantially the same result is achieved, the digital temperature conversion circuit of this application does not necessarily follow the same design. Figure 1 The first circuit block diagram shown is for reference only. Figure 1 As shown, the digital temperature conversion circuit 100 includes a frequency detection circuit 120, a voltage regulation circuit 130, and a digital temperature sensor circuit 110.

[0057] The digital temperature sensor circuit 110 is used to generate a first clock signal based on the ambient temperature. As the ambient temperature changes, the first clock signal generated by the digital temperature sensor circuit 110 will also change, that is, the digital temperature sensor circuit 110 can generate different first clock signals at different times.

[0058] The frequency detection circuit 120 is used to detect the frequency of the first clock signal and obtain the curvature information of the frequency-temperature change curve.

[0059] Voltage regulation circuit 130 is used to generate a first voltage signal based on curvature information;

[0060] The digital temperature sensor circuit 110 is also used to generate a second clock signal based on the ambient temperature and the first voltage signal, and to convert the second clock signal into a digital code. Specifically, the second clock signal is generated based on the ambient temperature and the first voltage signal, where the ambient temperature is the current ambient temperature.

[0061] In this embodiment, a digital temperature sensor circuit 110 generates a first clock signal based on the ambient temperature; a frequency detection circuit 120 detects the frequency of the first clock signal and obtains the curvature information of the frequency-temperature change curve; a voltage adjustment circuit 130 generates a first voltage signal based on the curvature information; and the digital temperature sensor circuit 110 generates a second clock signal based on the ambient temperature and the first voltage signal, converting the second clock signal into a digital code. In this embodiment, during temperature measurement, the digital temperature sensor circuit is calibrated based on the curvature of the frequency change of the first clock signal, causing it to generate a second clock signal after curvature correction. The digital code corresponding to the second clock signal yields a more accurate temperature value, thereby improving the accuracy of temperature measurement.

[0062] In some embodiments, the second circuit block diagram of the digital temperature conversion circuit is as follows: Figure 2 As shown, the voltage regulation circuit 130 includes a curvature voltage regulation circuit 131 and a voltage weighting circuit 132. The curvature voltage regulation circuit 131 is used to generate a second voltage signal based on curvature information, and the voltage weighting circuit 132 is used to weight the second voltage signal to obtain a first voltage signal.

[0063] In this embodiment, the curvature voltage adjustment circuit 131 generates a second voltage signal based on curvature information, and the voltage weighting circuit 132 performs weighted processing on the second voltage signal to obtain a first voltage signal acting on the digital temperature sensor circuit 110. The first voltage signal can precisely adjust the threshold voltage of the transistor in the digital temperature sensor circuit 110 to correct the curvature output of the digital temperature sensor circuit 110, thereby improving the temperature measurement accuracy of the digital temperature conversion circuit 100.

[0064] In some embodiments, the third circuit block diagram of the above-described digital temperature conversion circuit is as follows: Figure 3 As shown, the digital temperature sensor circuit 110 includes:

[0065] The first ring oscillator 111 is used to generate a second clock signal based on the ambient temperature and the first voltage signal;

[0066] The time amplifier 112 is used to amplify the period of the second clock signal to obtain the second pulse signal;

[0067] The time converter 114 is used to convert the second pulse signal into digital code.

[0068] In this embodiment, a first ring oscillator 111 generates a second clock signal based on the ambient temperature and a first voltage signal; the period of the second clock signal is amplified by a time amplifier 112 to obtain a second pulse signal; and the second pulse signal is converted into a digital code by a time converter 114; thus, a digital code related to the temperature can be accurately obtained.

[0069] In one specific embodiment, the clock period of the clock signal output by the first ring oscillator 111 is td = 2*k*t0, where k is the number of logic gates (including NAND gates and inverters) in the first ring oscillator 111, and t0 is the average propagation delay time of the logic gates in the first ring oscillator 111. The average propagation delay time t0 is a thermal signal that can be used to detect temperature, and its average propagation delay time t0 as a function of temperature can be approximately expressed as...

[0070]

[0071] Where T is the ambient temperature, L is the length of the transistor in the first ring oscillator 111, W is the width of the transistor in the first ring oscillator 111, and C is the length of the transistor in the first ring oscillator 111. L C is the load capacitance of the logic gate in the first ring oscillator 111. OX V is the gate oxide capacitance of the transistor. DD V is the power supply voltage of the first ring oscillator 111, μ(T) is the mobility, and V is the voltage of the ring oscillator 111. T (T) is the threshold voltage of the first ring oscillator 111. The temperature dependence formula for mobility is:

[0072]

[0073] Where T0 is the reference temperature, μ0 is the first constant, and km is the first process coefficient. The temperature dependence formula for the threshold voltage is:

[0074] V T (T)=V T (T0)+α(T-T0)

[0075] Where α is the second process coefficient.

[0076] In some embodiments, the time amplifier 112 includes a loop counter and a comparator to amplify the oscillation period td of the second clock signal according to a preset number of loops to obtain a second pulse signal. For example, a time amplifier 112 with a preset value n can be used to amplify the clock period td to generate a sufficiently wide delay pulse width.

[0077] Accordingly, the digital temperature sensor circuit 110 also includes a logic gate circuit 113 for amplifying the pulse width of the second pulse signal. The logic gate circuit 113 amplifies the pulse width of the second pulse signal to obtain an output pulse with a pulse width of tp. For example, the logic gate circuit 113 can be an XOR gate circuit. Using the XOR gate circuit, a sufficiently wide output pulse width tp can be generated, and tp(T) = n*td(T) can be obtained. The delay of the time amplifier 112 can be ignored because it is much smaller than n*td(T).

[0078] Accordingly, the time converter 114 can generate digital code based on the pulse-width-amplified second pulse signal (i.e., the output pulse tp of the logic gate circuit 113). As one implementation, a reference clock t can be used. RFE The pulse width tp is counted to obtain the digital output code (digital code) Dout. The expression for the digital output code Dout can be:

[0079]

[0080] Due to n and the reference clock t REF It is constant and references the clock t. REF Since it is not sensitive to temperature, the curve output by the digital sensor circuit 110 is similar to the curve of the first ring oscillator 111. Because the output curve of the first ring oscillator 111 has curvature, the curve output by the digital sensor circuit will have the same curvature. Therefore, a first clock signal is generated based on the ambient temperature, the frequency of the first clock signal is determined based on the first clock signal, and the curvature information of the frequency versus ambient temperature curve is obtained based on the frequency and ambient temperature. A first voltage signal is generated based on the curvature information and applied to the transistor of the first ring oscillator 111 to dynamically adjust the threshold voltage. By dynamically changing the threshold voltage, the frequency of the clock signal output by the first ring oscillator 111 is adjusted, achieving temperature compensation. This corrects the curvature of the output of the digital temperature sensor circuit 110, improving the temperature measurement accuracy of the digital temperature conversion circuit 100.

[0081] In some embodiments, the first ring oscillator 111 includes a plurality of delay units, at least one of which is connected to the voltage adjustment circuit 130 and receives a first voltage signal to adjust the delay duration of the delay unit according to the first voltage signal; the ring oscillator obtains two clock signals according to the delay duration of each delay unit.

[0082] In this embodiment, the delay duration of the delay unit is adjusted by the first voltage signal, and the ring oscillator obtains two clock signals according to the delay duration of each delay unit. Then, the digital code about the temperature can be accurately obtained through the second clock signal.

[0083] In some embodiments, the delay unit is an inverter, which includes an NMOS transistor and a PMOS transistor. The NMOS transistor and the PMOS transistor are respectively connected to the voltage regulation circuit 130 to receive the first voltage signal.

[0084] In this embodiment, the frequency of the clock signal output by the first ring oscillator 111 is adjusted by having the NMOS transistor and PMOS transistor receive the first voltage signal respectively.

[0085] In some embodiments, the substrates of the NMOS transistor and the PMOS transistor in the inverter are respectively connected to the voltage regulation circuit 130. In this way, the first voltage signal generated by the voltage regulation unit according to the curvature information is applied to the substrates of the NMOS transistor and the PMOS transistor in the inverter to adjust the substrate voltage of the NMOS transistor and the substrate voltage of the PMOS transistor in the inverter.

[0086] In one specific implementation, the circuit schematic of the first ring oscillator is as follows: Figure 4 As shown, Figure 4 In the first ring oscillator 111, the output of the voltage weighting circuit 132 is connected to the base of the NMOS and PMOS transistors respectively to adjust the voltage difference between the source and substrate of the NMOS and PMOS transistors, thereby adjusting the frequency of the clock signal output by the first ring oscillator 111. The inverter includes a transistor unit, which includes one NMOS transistor and one PMOS transistor, respectively used to receive the first voltage signal. The gate of the NMOS transistor and the gate of the PMOS transistor in each transistor unit are connected, and the source or drain of the NMOS transistor in each transistor unit is connected to the source or drain of the PMOS transistor. Correspondingly, in every two adjacent transistor units, the gate of the NMOS transistor in the preceding transistor unit is sequentially connected to the source or drain of the NMOS transistor in the following transistor unit, and the gate of the NMOS transistor in the last transistor unit is connected to the source or drain of the first NMOS transistor. The drains or sources of the NMOS transistors in every pair of transistor units are interconnected, and the drains or sources of the PMOS transistors in every pair of transistor units are interconnected.

[0087] In one specific embodiment, the threshold voltage of the transistors (NMOS and PMOS transistors) of the first ring oscillator 111 can also be expressed as:

[0088]

[0089] Among them, V TH V is the threshold voltage of the transistor. THO V is the second constant, γ is the volume effect coefficient, and V SB Let V be the voltage difference between the source and the substrate, and F be the third process factor. Therefore, the voltage difference V between the source and the substrate is adjusted by the first voltage signal. SB The threshold voltage of the transistor is adjusted, which in turn adjusts the delay time t0(T) of the inverter to calibrate the curvature of the output clock of the first ring oscillator 111 in order to obtain a more accurate temperature value.

[0090] In some embodiments, the time converter 114 is also used to calculate the number of clock cycles of the second pulse signal using a standard clock and a counter 115, and to generate a digital code based on the number of clock cycles.

[0091] The digital temperature conversion circuit 100 also includes a digital circuit that calculates the ambient temperature value based on the digital code.

[0092] In this embodiment, the clock cycle number of the second pulse signal is calculated using a standard clock and a counter 115, and a digital code is generated based on the clock cycle number. The ambient temperature value is then calculated based on the digital code, thus obtaining an accurate ambient temperature value.

[0093] In some implementations, the fourth circuit block diagram of the digital temperature conversion circuit is as follows: Figure 5 As shown, the first ring oscillator 111 includes a NAND gate and an inverter-based delay circuit for generating a first clock signal. The time amplifier 112 includes a loop counter and a comparator. The time amplifier 112 can amplify the oscillation period of the clock signal (first clock signal or second clock signal) according to a preset number of cycles to improve the resolution of the clock signal. Then, the gate circuit 113 is used to obtain a sufficiently wide output pulse signal tp (the second pulse signal after pulse width amplification). Figure 5 In the process, the time converter 114 includes a counter 115 and an AND gate 116. The REF terminal can be input with a standard clock (reference clock). The width of the pulse signal tp can be counted using the standard clock and the counter 115 to realize the conversion between time and digital. The counter 115 and the AND gate 116 can be regarded as the time converter 114. The logic gate circuit 113 can be an XOR gate circuit.

[0094] In the various embodiments described above, optionally, the first clock signal and the second clock signal can be generated by the same ring oscillator, for example, both generated by the first ring oscillator 111. Alternatively, the first clock signal and the second clock signal can be generated by different ring oscillators, for example, the first clock signal can be generated by an additional second ring oscillator 140, and the second clock signal can be generated by the aforementioned first ring oscillator 111.

[0095] In some embodiments, when both the first clock signal and the second clock signal are generated by the first ring oscillator 111, the first ring oscillator 111 is further configured to: generate the first clock signal according to the ambient temperature; and adjust the frequency of the first clock signal according to the first voltage signal to obtain the second clock signal.

[0096] The digital temperature conversion circuit 100 provided in this application embodiment generates a first clock signal based on the ambient temperature through a digital temperature sensor circuit 110; detects the frequency of the first clock signal through a frequency detection circuit 120 and obtains the curvature information of the frequency-temperature change curve; generates a first voltage signal based on the curvature information through a voltage adjustment circuit 130; and generates a second clock signal based on the ambient temperature and the first voltage signal through the digital temperature sensor circuit 110, and converts the second clock signal into a digital code. During temperature measurement, the digital temperature sensor circuit is calibrated based on the curvature of the frequency change of the first clock signal to generate a second clock signal after curvature correction. A more accurate temperature value can be obtained from the digital code corresponding to the second clock signal, thereby improving the accuracy of temperature measurement.

[0097] In some embodiments, when the first clock signal and the second clock signal are generated by different ring oscillators, such as Figure 6 The diagram shown is a fifth circuit block diagram of a digital temperature conversion circuit according to an embodiment of this application. The digital temperature conversion circuit 100 further includes a second ring oscillator 140, used to convert the ambient temperature into a first clock signal. The principle and implementation of the second ring oscillator 140 in generating the first clock signal are the same as those of the first ring oscillator 111, and will not be described again. Optionally, the configuration of the first ring oscillator 111 and the configuration of the second ring oscillator 140 can be the same or different.

[0098] In some implementations, such as Figure 7 The diagram shown is the sixth circuit block diagram of the aforementioned digital temperature conversion circuit. Figure 7 In the circuit, the second ring oscillator 140 generates a first clock signal based on the ambient temperature; the frequency detection circuit 120 detects the frequency of the first clock signal and obtains the curvature information of the frequency-temperature change curve; the voltage regulation circuit 130 generates a first voltage signal based on the curvature information; the first ring oscillator 111 of the digital temperature sensor circuit 110 generates a second clock signal based on the ambient temperature and the first voltage signal, and converts the second clock signal into a digital code; this enables temperature measurement and improves the accuracy of temperature measurement.

[0099] The digital temperature conversion circuit 100 provided in this application embodiment can test the frequency of the clock signal output by the first ring oscillator 111 at multiple temperature points, store the frequency information at different temperatures in a memory, obtain different curvature information based on frequency detection, and then obtain the corresponding voltage signal through the curvature voltage adjustment circuit 131. The voltage signal is then weighted by the voltage weighting circuit 132 to obtain a voltage signal of corresponding amplitude, and the threshold voltage of the inverter transistor of the first ring oscillator 111 is controlled to dynamically adjust the threshold voltage. The frequency of the clock signal output by the first ring oscillator 111 is adjusted by the dynamic change of the threshold voltage to achieve temperature compensation, thereby realizing curvature correction of the output of the digital temperature sensor circuit 110 and improving the temperature measurement accuracy of the digital temperature conversion circuit 100.

[0100] The digital temperature conversion circuit 100 provided in this application embodiment can test the frequency of the clock signal output by the second ring oscillator 140 at multiple temperature points, store the frequency information at different temperatures in a memory, obtain different curvature information based on frequency detection, and then obtain the corresponding voltage signal through the curvature voltage adjustment circuit 131. The voltage signal is then weighted by the voltage weighting circuit 132 to obtain a voltage signal of corresponding amplitude, and control the threshold voltage of the inverter transistor of the first ring oscillator 111 to dynamically adjust the threshold voltage. By dynamically changing the threshold voltage, the frequency of the clock signal output by the first ring oscillator 111 is adjusted to achieve temperature compensation, thereby realizing curvature correction of the output of the digital temperature sensor circuit 110 and improving the temperature measurement accuracy of the digital temperature conversion circuit 100.

[0101] This application provides a digital temperature conversion method, the flowchart of which is shown below. Figure 8 As shown, this digital temperature conversion method includes the following steps:

[0102] S1. Generate the first clock signal based on the ambient temperature;

[0103] S2. Detect the frequency of the first clock signal and obtain the curvature information of the frequency-temperature change curve.

[0104] S3. Generate the first voltage signal based on the curvature information;

[0105] S4. Generate a second clock signal based on the ambient temperature and the first voltage signal, and convert the second clock signal into a digital code.

[0106] In this embodiment, a first clock signal is generated based on the ambient temperature; the frequency of the first clock signal is detected, and the curvature information of the frequency-temperature change curve is obtained; a first voltage signal is generated based on the curvature information; a second clock signal is generated based on the ambient temperature and the first voltage signal, and the second clock signal is converted into a digital code; during temperature measurement, the digital temperature sensor circuit is calibrated based on the curvature of the frequency change of the first clock signal, so that it generates a second clock signal after curvature correction, and a more accurate temperature value can be obtained from the digital code corresponding to the second clock signal, thereby improving the accuracy of temperature measurement.

[0107] In some embodiments, generating a first voltage signal based on curvature information includes: generating a second voltage signal based on curvature information, and performing weighted processing on the second voltage signal to obtain the first voltage signal.

[0108] In some embodiments, generating a second clock signal based on ambient temperature and a first voltage signal includes: obtaining a delay duration based on the first voltage signal, and obtaining the second clock signal based on the delay duration and ambient temperature.

[0109] In some embodiments, the second clock signal is converted into a digital code, including: calculating the number of clock cycles of the second pulse signal using a standard clock and a counter, and generating a digital code based on the number of clock cycles.

[0110] In some embodiments, the digital temperature conversion method further includes calculating the ambient temperature value based on the digital code.

[0111] This application provides a chip that includes the digital temperature conversion circuit described in any of the above embodiments.

[0112] This application provides an electronic device, including the digital temperature conversion circuit or the chip described in any of the above embodiments.

[0113] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0114] The above embodiments merely illustrate preferred implementations of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A digital temperature conversion circuit, characterized in that, This includes a frequency detection circuit, a voltage regulation circuit, and a digital temperature sensor circuit. The digital temperature sensor circuit is used to generate a first clock signal based on the ambient temperature. The frequency detection circuit is used to detect the frequency of the first clock signal and obtain the curvature information of the frequency-temperature change curve. The voltage regulation circuit is used to generate a first voltage signal based on the curvature information; The digital temperature sensor circuit is further configured to generate a second clock signal based on the ambient temperature and the first voltage signal, and convert the second clock signal into a digital code. The digital temperature sensor circuit includes a first ring oscillator, a time amplifier, and a time converter. The first ring oscillator is used to generate a second clock signal based on the ambient temperature and the first voltage signal. The time amplifier is used to amplify the period of the second clock signal to obtain a second pulse signal. The time converter is used to convert the second pulse signal into the digital code.

2. The digital temperature conversion circuit according to claim 1, characterized in that, The voltage regulation circuit includes a curvature voltage regulation circuit and a voltage weighting circuit. The curvature voltage regulation circuit is used to generate a second voltage signal based on the curvature information. The voltage weighting circuit is used to perform weighting processing on the second voltage signal to obtain the first voltage signal.

3. The digital temperature conversion circuit according to claim 1, characterized in that, The first ring oscillator includes multiple delay units, at least one of the delay units is connected to the voltage regulation circuit and receives the first voltage signal, so as to adjust the delay duration of the delay unit according to the first voltage signal; The first ring oscillator obtains the second clock signal based on the delay duration of each delay unit.

4. The digital temperature conversion circuit according to claim 3, characterized in that, The delay unit is an inverter, which includes an NMOS transistor and a PMOS transistor. The NMOS transistor and the PMOS transistor are respectively connected to the voltage regulation circuit to receive the first voltage signal.

5. The digital temperature conversion circuit according to claim 4, characterized in that, The substrates of the NMOS transistor and the PMOS transistor are respectively connected to the voltage regulation circuit.

6. The digital temperature conversion circuit according to claim 1, characterized in that: The time converter is also used to calculate the number of clock cycles of the second pulse signal using a standard clock and a counter, and to generate the digital code based on the number of clock cycles; The digital temperature conversion circuit also includes a digital circuit, which is used to calculate the ambient temperature value based on the digital code.

7. The digital temperature conversion circuit according to any one of claims 1-6, characterized in that, The digital temperature sensor circuit also includes: A second ring oscillator is used to convert the ambient temperature into the first clock signal.

8. The digital temperature conversion circuit according to any one of claims 1-6, characterized in that, The first ring oscillator is also used for: The first clock signal is generated based on the ambient temperature; and... The frequency of the first clock signal is adjusted according to the first voltage signal to obtain the second clock signal.

9. A digital temperature conversion method, characterized in that, Includes the following steps: A first clock signal is generated based on the ambient temperature; The frequency of the first clock signal is detected, and the curvature information of the curve of the frequency changing with the ambient temperature is obtained; A first voltage signal is generated based on the curvature information; A second clock signal is generated based on the ambient temperature and the first voltage signal, and the second clock signal is converted into digital code, including: A second clock signal is generated based on the ambient temperature and the first voltage signal. The period of the second clock signal is amplified to obtain a second pulse signal, and the second pulse signal is converted into the digital code.

10. The digital temperature conversion method according to claim 9, characterized in that, Generating a first voltage signal based on the curvature information includes: generating a second voltage signal based on the curvature information, and performing weighted processing on the second voltage signal to obtain the first voltage signal.

11. The digital temperature conversion method according to claim 9, characterized in that, Generating a second clock signal based on the ambient temperature and the first voltage signal includes: obtaining a delay duration based on the first voltage signal, and obtaining the second clock signal based on the delay duration and the ambient temperature.

12. The digital temperature conversion method according to claim 9, characterized in that, The second clock signal is converted into a digital code, which includes: calculating the number of clock cycles of the second pulse signal using a standard clock and a counter, and generating the digital code based on the number of clock cycles.

13. The digital temperature conversion method according to claim 9, characterized in that, The digital temperature conversion method further includes: calculating the ambient temperature value based on the digital code.

14. A chip, characterized in that, Includes the digital temperature conversion circuit as described in any one of claims 1-8.

15. An electronic device, characterized in that, Includes the digital temperature conversion circuit as described in any one of claims 1-8 or the chip as described in claim 14.

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