Temperature detection circuit, image sensor and vehicle

Abstract

The invention discloses a temperature detection circuit, an image sensor and a vehicle. The temperature detection circuit can comprise a temperature voltage acquisition circuit, an addition and subtraction operation circuit and a conversion quantization circuit. The temperature voltage acquisition circuit is configured to acquire a temperature voltage. In the first mode, the addition and subtraction operation circuit can process the temperature voltage and output a first voltage, in the second mode, the addition and subtraction operation circuit can process the temperature voltage and output a second voltage, and the first voltage is larger than the second voltage. The conversion quantization circuit may determine a reference voltage value according to the first voltage. The conversion quantization circuit can also determine an operating voltage value according to the second voltage. The addition and subtraction operation circuit can reduce the voltage value of the first voltage to a proper voltage value, thereby effectively reducing the voltage difference between the reference voltage range and the working voltage range of the temperature detection circuit. The working efficiency of the temperature detection circuit is improved while high-precision working of the temperature detection circuit in the image sensor is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of temperature detection, and more specifically, to a temperature detection circuit, an image sensor and a vehicle. Background Art

[0002] In the related art, a programmable gain amplifier is used to amplify a weak signal to a level strong enough to be detected and processed, so as to improve the detection accuracy of the temperature detection circuit. However, the programmable gain amplifier will cause an excessively large voltage difference between the reference voltage and the operating voltage range, which will prolong the conversion quantization time of the temperature detection circuit and reduce the working efficiency of the temperature detection circuit. Summary of the invention

[0003] Embodiments of the present application provide a temperature detection circuit, an image sensor, and a vehicle.

[0004] The temperature detection circuit provided in the embodiment of the present application may include a temperature voltage acquisition circuit, an addition and subtraction operation circuit, and a conversion quantization circuit. Among them, the temperature voltage acquisition circuit is configured to collect temperature voltage, and the temperature voltage is determined according to the ambient temperature of the temperature detection circuit. The addition and subtraction operation circuit is connected to the temperature voltage acquisition circuit, and the addition and subtraction operation circuit can operate in a first mode or a second mode. In the first mode, the addition and subtraction operation circuit can process the temperature voltage and output a first voltage. In the second mode, the addition and subtraction operation circuit can process the temperature voltage and output a second voltage, and the first voltage is greater than the second voltage. The conversion quantization circuit is connected to the addition and subtraction operation circuit, and the conversion quantization circuit can determine the reference voltage value of the temperature detection circuit according to the first voltage. The conversion quantization circuit can also determine the operating voltage value of the temperature detection circuit according to the second voltage.

[0005] The addition and subtraction circuit of the embodiment of the present application can adjust the temperature voltage based on different modes. In the first mode, the addition and subtraction circuit can reduce the voltage value of the first voltage to a suitable voltage value, thereby reducing the reference voltage value of the temperature detection circuit to a certain voltage value, effectively reducing the voltage difference between the reference voltage of the temperature detection circuit and the operating voltage range. While ensuring the high-precision operation of the temperature detection circuit, it also saves conversion quantization time and improves the working efficiency of the temperature detection circuit.

[0006] In some embodiments, the addition and subtraction operation circuit may include a first input terminal, a first operation branch, a second operation branch, and a first output terminal. The first input terminal may be connected to a temperature voltage, and in a first mode, the first input terminal is connected to the first output terminal through the first operation branch, and in a second mode, the first input terminal is connected to the first output terminal through the second operation branch.

[0007] In some embodiments, the first operational branch includes a first operational amplifier, a positive connection branch, a negative connection branch, a feedback branch, an auxiliary voltage terminal and a first switch, and the auxiliary voltage terminal can be connected to a predetermined auxiliary voltage. The positive input terminal of the first operational amplifier is connected to the first input terminal through the positive connection branch, the negative input terminal of the first operational amplifier is connected to the auxiliary voltage terminal through the negative connection branch, the negative input terminal is connected to the output terminal of the first operational amplifier through the feedback branch, and the output terminal of the first operational amplifier is connected to the first output terminal through the first switch.

[0008] In some embodiments, the positive connection branch includes a first resistor and a second resistor, the positive input terminal of the first operational amplifier is connected to the first input terminal through the first resistor, and the positive input terminal of the first operational amplifier is grounded through the second resistor. The negative connection branch includes a third resistor, the feedback branch includes a fourth resistor, the auxiliary voltage terminal is connected to the negative input terminal of the first operational amplifier through the third resistor, and the negative input terminal of the first operational amplifier is connected to the output terminal of the first operational amplifier through the fourth resistor.

[0009] In some embodiments, the second operation branch includes a second switch, and the first input terminal is connected to the first output terminal through the second switch.

[0010] In some embodiments, the conversion quantization circuit may include a ramp generating circuit, a comparator circuit, and a counter circuit. The ramp generating circuit may generate a ramp voltage signal. The comparator circuit may be connected to the ramp signal generating circuit and the addition and subtraction operation circuit. The comparator circuit may determine a first identification signal based on the ramp voltage signal and the first voltage. The comparator circuit may also determine a second identification signal based on the ramp voltage signal and the second voltage. The counter circuit may determine a reference voltage value of the temperature detection circuit based on the first identification signal count. The counter circuit may also determine an operating voltage value of the temperature detection circuit based on the second identification signal count.

[0011] In some embodiments, the comparator circuit includes a comparator, a third switch and a fourth switch. The comparator includes a second input terminal, a third input terminal and a second output terminal. The second input terminal is connected to the ramp generating circuit through the third switch, the third input terminal is connected to the addition and subtraction operation circuit through the fourth switch, and the second output terminal is connected to the counter circuit.

[0012] In some embodiments, the comparator circuit includes a first capacitor and a second capacitor, the first capacitor is connected between the third switch and the second input terminal, and the second capacitor is connected between the fourth switch and the third input terminal.

[0013] In some embodiments, the comparator circuit further includes a fifth switch, a sixth switch, a seventh switch, and an eighth switch. The first end of the first capacitor is connected to the addition and subtraction circuit through the fifth switch, the second end of the first capacitor is connected to the reset voltage source of the comparator through the sixth switch, the first end of the second capacitor is connected to the addition and subtraction circuit through the seventh switch, and the second end of the second capacitor is connected to the reset voltage source of the comparator through the eighth switch.

[0014] In some embodiments, the temperature voltage acquisition circuit includes at least two current sources and at least two detection transistors. Each current source is connected to the first electrode of the corresponding detection transistor, and the second electrode of each detection transistor is grounded. The temperature voltage acquisition circuit is configured to output the temperature voltage according to the first electrode voltage of at least two detection transistors.

[0015] In some embodiments, at least two of the detection transistors have the same voltage temperature coefficient. The currents of the current sources connected to the detection transistors with the same voltage temperature coefficient are different.

[0016] In some embodiments, the temperature voltage acquisition circuit includes a differential amplifier unit, and the differential amplifier unit is configured to output the temperature voltage according to a voltage difference between first electrode voltages of at least two detection transistors.

[0017] An embodiment of the present application further provides an image sensor, which may include the temperature detection circuit of the above embodiment.

[0018] An embodiment of the present application further provides a vehicle, which may include the temperature detection circuit or image sensor of the above embodiment.

[0019] The embodiment of the present application discloses a vehicle-mounted temperature detection circuit. The temperature detection circuit may include a temperature voltage acquisition circuit, an addition and subtraction operation circuit, and a conversion quantization circuit. Among them, the temperature voltage acquisition circuit is configured to collect temperature voltage, and the temperature voltage is determined according to the ambient temperature of the temperature detection circuit. The addition and subtraction operation circuit is connected to the temperature voltage acquisition circuit, and the addition and subtraction operation circuit can operate in a first mode or a second mode. In the first mode, the addition and subtraction operation circuit can process the temperature voltage and output a first voltage. In the second mode, the addition and subtraction operation circuit can process the temperature voltage and output a second voltage, and the first voltage is greater than the second voltage. The conversion quantization circuit is connected to the addition and subtraction operation circuit, and the conversion quantization circuit can determine the reference voltage value of the temperature detection circuit according to the first voltage. The conversion quantization circuit can also determine the operating voltage value of the temperature detection circuit according to the second voltage.

[0020] The addition and subtraction circuit of the embodiment of the present application can adjust the temperature voltage based on different modes. In the first mode, the addition and subtraction circuit can reduce the voltage value of the first voltage to a suitable voltage value, that is, the reference voltage value of the temperature detection circuit can be reduced to a certain voltage value, effectively reducing the voltage difference between the reference voltage of the temperature detection circuit and the operating voltage range. While ensuring the high-precision operation of the temperature detection circuit, it also saves conversion quantization time and improves the working efficiency of the temperature detection circuit.

[0021] Additional aspects and advantages of the embodiments of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0023] Figure 1 is a schematic diagram of a temperature detection circuit according to an embodiment of the present application;

[0024] Figure 2 is a schematic diagram of an addition and subtraction operation circuit according to an embodiment of the present application;

[0025] Figure 3 is a schematic diagram of a conversion quantization circuit according to an embodiment of the present application;

[0026] Figure 4 is a schematic diagram of a voltage signal and a ramp voltage signal output by an addition and subtraction operation circuit according to an embodiment of the present application;

[0027] Figure 5 is a schematic diagram of a comparator circuit according to an embodiment of the present application;

[0028] Figure 6 is a schematic diagram of a temperature and voltage acquisition circuit according to an embodiment of the present application;

[0029] Figure 7 It is a schematic diagram of a vehicle according to an embodiment of the present application.

[0030] Description of main component symbols:

[0031] Temperature and voltage acquisition circuit 100, current source 110, detection transistor 120, differential amplifier unit 130, addition and subtraction operation circuit 200, first input terminal 210, first operation branch 220, first operational amplifier 221, positive connection branch 222, negative connection branch 223, feedback branch 224, auxiliary voltage terminal 225, first switch 226, second operation branch 230, second switch 231, first output terminal 240, conversion quantization circuit 300, ramp generation circuit 310, comparator circuit 320, comparator 321, third switch 322, fourth switch 323, first capacitor 324, second capacitor 325, fifth switch 326, sixth switch 327, seventh switch 328, eighth switch 329, counter circuit 330, temperature detection circuit 1000, image sensor 2000, vehicle 10000. DETAILED DESCRIPTION

[0032] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions from beginning to end. The embodiments described below with reference to the accompanying drawings are optional and are only used to explain the embodiments of the present application, and cannot be understood as limiting the embodiments of the present application.

[0033] In the related art, a programmable gain amplifier can be used to amplify weak signals to a level strong enough to be detected and processed, so as to improve the detection accuracy of the temperature detection circuit. However, the programmable gain amplifier will cause an excessively large voltage difference between the reference voltage and the operating voltage range, which will prolong the conversion quantization time of the temperature detection circuit and reduce the working efficiency of the temperature detection circuit.

[0034] See also Figure 1 , the embodiment of the present application provides a temperature detection circuit 1000. The temperature detection circuit 1000 may include a temperature voltage acquisition circuit 100, an addition and subtraction operation circuit 200, and a conversion quantization circuit 300. Among them, the temperature voltage acquisition circuit 100 is configured to collect temperature voltage, and the temperature voltage is determined according to the ambient temperature of the temperature detection circuit 1000. The addition and subtraction operation circuit 200 is connected to the temperature voltage acquisition circuit 100, and the addition and subtraction operation circuit 200 can work in a first mode or a second mode. In the first mode, the addition and subtraction operation circuit 200 can process the temperature voltage and output a first voltage. In the second mode, the addition and subtraction operation circuit 200 can process the temperature voltage and output a second voltage, and the first voltage is greater than the second voltage. The conversion quantization circuit 300 is connected to the addition and subtraction operation circuit 200, and the conversion quantization circuit 300 can determine the reference voltage value of the temperature detection circuit 1000 according to the first voltage. The conversion quantization circuit 300 can also determine the operating voltage value of the temperature detection circuit 1000 according to the second voltage.

[0035] Specifically, the temperature sampling circuit may include a temperature-sensitive electronic element. The temperature-sensitive electronic element may include a temperature-sensitive resistor whose resistance value changes with temperature, a temperature-sensitive capacitor whose capacitance value changes with temperature, and a temperature-sensitive inductor whose inductance value changes with temperature. The temperature-sensitive electronic element may also include a semiconductor device whose voltage value changes with temperature. In the case of temperature changes, the voltage value output by the temperature-sensitive electronic element, or the current value flowing through the temperature-sensitive electronic element will change, so that the temperature voltage acquisition circuit 100 can determine the temperature voltage according to the ambient temperature of the temperature detection circuit 1000.

[0036] The addition and subtraction operation circuit 200 may include corresponding operator circuits, such as an adder circuit, a subtractor circuit, a proportional amplifier circuit, etc. The addition and subtraction operation circuit 200 may calculate and process the temperature voltage collected by the temperature voltage collection circuit 100 based on corresponding operation rules.

[0037] In the first mode and the second mode, the addition and subtraction circuit 200 can calculate the temperature voltage based on different operation rules. In the first mode, the calculated voltage can be set as a first voltage, and in the second mode, the calculated voltage can be set as a second voltage, and the first voltage is greater than the second voltage.

[0038] The conversion quantization circuit 300 can sample and quantize the analog signal provided by the addition and subtraction operation circuit 200 and obtain a corresponding data signal. The first voltage can be set as a quantized calibration voltage of the reference voltage, and the second voltage can be set as a quantized calibration voltage of the working voltage. In the first mode, the addition and subtraction operation circuit 200 can calculate and process the temperature voltage based on the first operation rule to obtain the first voltage, and the conversion quantization circuit 300 can determine the reference voltage value of the temperature detection circuit 1000 after quantizing the first voltage. In the second mode, the addition and subtraction operation circuit 200 can calculate and process the temperature voltage based on the second operation rule to obtain the second voltage, and the conversion quantization circuit 300 can determine the working voltage value of the temperature detection circuit 1000 after quantizing the second voltage.

[0039] It can be understood that the first voltage is greater than the second voltage, that is, the quantized calibration voltage of the reference voltage is greater than the quantized calibration voltage of the operating voltage, so that the reference voltage of the temperature detection circuit 1000 can drop by a certain voltage value, which can effectively reduce the voltage difference between the reference voltage and the operating voltage range.

[0040] The temperature detection circuit 1000 according to the embodiment of the present application not only ensures high-precision operation, but also saves conversion quantization time and improves the working efficiency of the temperature detection circuit 1000 .

[0041] In some embodiments, the addition and subtraction operation circuit 200 may include a first input terminal 210, a first operation branch 220, a second operation branch 230, and a first output terminal 240. The first input terminal 210 may be connected to a temperature voltage, and in a first mode, the first input terminal 210 is connected to the first output terminal 240 through the first operation branch 220, and in a second mode, the first input terminal 210 is connected to the first output terminal 240 through the second operation branch 230.

[0042] Specifically, Figure 2 For example, the addition and subtraction circuit 200 may include a signal terminal V tem0 And the signal terminal V tem The first input terminal 210 can be set as a signal terminal V tem0 , the first output terminal 240 can be set as the signal terminal V tem .

[0043] Signal terminal V tem0 It can be connected to the temperature acquisition circuit and connected to the temperature voltage provided by the temperature acquisition circuit. In the first mode, the signal terminal V tem0 Through the first operation branch 220 and the signal terminal V tem In the second mode, the signal terminal V tem0 Through the second operation branch 230 and the signal terminal V tem connect.

[0044] In the first mode, the first operation branch 220 is connected to the signal terminal V tem0 With the signal terminal V tem , the second operation branch 230 is disconnected. The first operation branch 220 can operate on the signal terminal V based on the corresponding first operation rule. tem0 The voltage connected is calculated and processed, and the first voltage is obtained by the signal terminal V tem Output.

[0045] In the second mode, the second operation branch 230 is connected to the signal terminal V tem0 With the signal terminal V tem , the first operation branch 220 is disconnected. The second operation branch 230 can be based on the corresponding second operation rule to the signal terminal V tem0 The voltage connected is calculated and processed, and the corresponding second voltage is obtained by the signal terminal V tem Output.

[0046] In this way, the addition and subtraction circuit 200 can be controlled to operate in the first mode or the second mode by controlling the on and off of the first operation branch 220 and the second operation branch 230 .

[0047] In some embodiments, the first operation branch 220 includes a first operational amplifier 221, a positive connection branch 222, a negative connection branch 223, a feedback branch 224, an auxiliary voltage terminal 225, and a first switch 226. The auxiliary voltage terminal 225 can be connected to a predetermined auxiliary voltage. The positive input terminal of the first operational amplifier 221 is connected to the first input terminal 210 through the positive connection branch 222, the negative input terminal of the first operational amplifier 221 is connected to the auxiliary voltage terminal 225 through the negative connection branch 223, the negative input terminal is connected to the output terminal of the first operational amplifier 221 through the feedback branch 224, and the output terminal of the first operational amplifier 221 is connected to the first output terminal 240 through the first switch 226.

[0048] In some embodiments of the present application, the positive connection branch 222 includes a first resistor and a second resistor, the positive input terminal of the first operational amplifier 220 is connected to the first input terminal 210 through the first resistor, and the positive input terminal of the first operational amplifier 220 is grounded through the second resistor. The negative connection branch 223 includes a third resistor, the feedback branch 224 includes a fourth resistor, the auxiliary voltage terminal 225 is connected to the negative input terminal of the first operational amplifier 220 through the third resistor, and the negative input terminal of the first operational amplifier 220 is connected to the output terminal of the first operational amplifier 220 through the fourth resistor.

[0049] Specifically, Figure 2 For example, the positive connection branch 222 may include a resistor element R b And the resistance element R p Among them, the resistance element R p is the first resistor, the resistor element R b is the second resistor. Signal terminal V tem0 The resistor element R p is connected to the positive input terminal of the first operational amplifier 221. The positive input terminal of the first operational amplifier 221 can be connected to the positive input terminal of the first operational amplifier 221 through the resistor element R b Ground.

[0050] The auxiliary voltage terminal 225 can be set as the signal terminal V sub , the negative connection branch 223 may include a resistor element R n , the resistance element R n It can be a third resistor. Signal terminal V sub The resistor element R n The feedback branch 224 may include a resistor element R f , the resistance element R f The negative input terminal of the first operational amplifier 221 can be connected to the resistor element R fThe first switch 226 may include a switch element S1, and the output end of the first operational amplifier 221 may be connected to the signal end V tem connect.

[0051] In the first mode, the switch element S1 is closed and the signal terminal V sub The input voltage can be set to voltage U sub , signal terminal V tem0 The input voltage can be set to voltage U tem0 , signal terminal V tem The voltage provided can be set to voltage U o , voltage U o satisfy:

[0052] In the first mode, the signal terminal V tem0 The input voltage can be set to voltage U tem0，ref , signal terminal V tem The voltage provided can be set as the quantitative calibration voltage U of the reference voltage tem，ref , voltage U tem，ref satisfy:

[0053] Resistor element R n , resistance element R b And the resistance element R p According to the voltage U tem，ref The voltage value is set so that the regulated voltage U tem，ref The voltage value is less than the voltage U tem0，ref Voltage value.

[0054] In some embodiments, the second operation branch 230 includes a second switch 231 , and the first input terminal 210 is connected to the first output terminal 240 via the second switch 231 .

[0055] Specifically, Figure 2 For example, the second switch 231 may include a switch element S2, a signal terminal V tem0 Through the switch element S2 and the signal terminal V tem connect.

[0056] In the second mode, the switch element S2 is closed and the signal terminal V tem0 With the signal terminal V tem Connected, signal terminal V tem The voltage provided can be set to voltage U o , U o =U tem0 .

[0057] In the first mode, the voltage U o Can be set to be less than the voltage U tem0 In the second mode, the voltage U o Can be set equal to the voltage U tem0 Since the reference voltage output by the addition and subtraction operation circuit is greater than the temperature operating voltage, the first voltage obtained by the addition and subtraction operation circuit 200 operating in the first mode is greater than the second voltage obtained by the second mode.

[0058] Reference Figure 3 In some embodiments, the conversion quantization circuit 300 may include a ramp generating circuit 310, a comparator circuit 320, and a counter circuit 330. The ramp generating circuit 310 may generate a ramp voltage signal. The comparator circuit 320 may be connected to the ramp signal generating circuit and the addition and subtraction operation circuit 200. The comparator circuit 320 may determine a first identification signal according to the ramp voltage signal and the first voltage. The comparator circuit 320 may also determine a second identification signal according to the ramp voltage signal and the second voltage. The counter circuit 330 may determine a reference voltage value of the temperature detection circuit 1000 according to the first identification signal count. The counter circuit 330 may also determine an operating voltage value of the temperature detection circuit 1000 according to the second identification signal count.

[0059] Specifically, the ramp generating circuit 310 can generate a ramp voltage signal, which can be a voltage signal whose voltage value changes linearly with time. The ramp generating circuit 310 can use an integration circuit composed of multiple switches, capacitors and operational amplifiers, apply a constant voltage to the input end of the operational amplifier, and obtain a ramp voltage signal at the output end of the integration circuit through switch switching.

[0060] The comparator circuit 320 can be connected to the signal terminal V tem connected to the addition and subtraction circuit 200 and connected to the addition and subtraction circuit 200 through the signal terminal V tem The comparator circuit 320 can also be connected to the output voltage of the addition and subtraction circuit 200 through the signal terminal V ramp and the ramp generating circuit 310, and through the signal terminal V ramp The comparator circuit 320 can be connected to the ramp voltage signal generated by the ramp generating circuit 310 according to the signal terminal V tem Access voltage and signal terminal V ramp The comparison result of the access voltage is output as an identification signal to the counter circuit 330 .

[0061] The counter can count the valid pulses of the identification signal provided by the comparator circuit 320, thereby realizing the conversion quantization of the analog voltage signal.

[0062] When the addition and subtraction operation circuit 200 operates in the first mode, the comparator circuit 320 can generate a signal through the signal terminal V tem The first voltage output by the addition and subtraction operation circuit 200 is connected. The comparator circuit 320 can output a first identification signal according to the comparison result between the first voltage and the ramp voltage signal, and the counter circuit 330 can count the effective pulses of the first identification signal to realize the conversion quantization of the reference voltage value.

[0063] When the addition and subtraction operation circuit 200 operates in the second mode, the comparator circuit 320 can generate a signal through the signal terminal V tem The second voltage output by the addition and subtraction operation circuit 200 is connected. The comparator circuit 320 can output a second identification signal according to the comparison result between the second voltage and the ramp voltage signal, and the counter circuit 330 can count the effective pulses of the second identification signal to realize the conversion quantization of the temperature working voltage value.

[0064] by Figure 4 For example, at time t0, the addition and subtraction operation circuit 200 operates in the first mode, and the addition and subtraction operation circuit 200 can tem Output the first voltage. At time t1, the ramp voltage increases, and the output voltage of the comparator circuit 320 changes from a high level to a low level. When the ramp voltage starts to decrease, the counter circuit 330 starts counting. At time t2, the signal terminal V tem The voltage connected to the signal terminal V ramp The input voltage is the same, the output voltage of the comparator 321 changes from a low level to a high level, the counter circuit 330 stops counting, and the conversion quantization of the reference voltage signal of the temperature detection circuit 1000 is completed.

[0065] At time t3, the ramp voltage increases. At time t4, the addition and subtraction operation circuit 200 operates in the second mode. The addition and subtraction operation circuit 200 can tem The output voltage of the comparator circuit 320 changes from a high level to a low level. When the ramp voltage starts to decrease, the counter circuit 330 starts counting. At time t5, the signal terminal V tem The voltage connected to the signal terminal V ramp The input voltage is the same, the output voltage of the comparator 321 changes from a low level to a high level, the counter circuit 330 stops counting, and the conversion quantization of the working voltage signal of the temperature detection circuit 1000 is completed.

[0066] Reference Figure 5In some embodiments, the comparator circuit 320 includes a comparator 321, a third switch 322, and a fourth switch 323. The comparator 321 includes a second input terminal, a third input terminal, and a second output terminal. The second input terminal is connected to the ramp generating circuit 310 through the third switch 322, the third input terminal is connected to the addition and subtraction operation circuit 200 through the fourth switch 323, and the second output terminal is connected to the counter circuit 330.

[0067] Specifically, the third switch 322 may include a switch element S3, and the fourth switch 323 may include a switch element S4. ramp The signal terminal V tem The third input terminal can be connected via the switch element S4.

[0068] The second input terminal can be set as the positive input terminal of the comparator 321, and the third input terminal can be set as the negative input terminal of the comparator 321. The second input terminal can also be set as the negative input terminal of the comparator 321, and the third input terminal can also be set as the positive input terminal of the comparator 321. The second output terminal can be set as the output terminal of the comparator 321.

[0069] When the addition and subtraction circuit 200 operates in the first mode or the second mode, the switch element S3 and the switch element S4 can be in a closed state. tem The voltage connected to the signal terminal V ramp The magnitude relationship of the input voltage provides an identification signal to the counter circuit 330 .

[0070] Reference Figure 5 In some embodiments, the comparator circuit 320 includes a first capacitor 324 and a second capacitor 325, the first capacitor 324 is connected between the third switch 322 and the second input terminal, and the second capacitor 325 is connected between the fourth switch 323 and the third input terminal.

[0071] Specifically, the first capacitor 324 may include a capacitor C1, and the second capacitor 325 may include a capacitor C2. The capacitor C1 may be connected between the switch element S3 and the second input terminal of the comparator 321, and the capacitor C2 may be connected between the switch element S4 and the third input terminal of the comparator 321.

[0072] The first capacitor 324 and the second capacitor 325 are arranged at the input end of the comparator 321 , and can sample the input signal and act on the comparator 321 to obtain a comparison result.

[0073] Reference Figure 5In some embodiments, the comparator circuit 320 further includes a fifth switch 326, a sixth switch 327, a seventh switch 328, and an eighth switch 329. The first end of the first capacitor 324 is connected to the addition and subtraction operation circuit 200 through the fifth switch 326, the second end of the first capacitor 324 is connected to the reset voltage source of the comparator 321 through the sixth switch 327, the first end of the second capacitor 325 is connected to the addition and subtraction operation circuit 200 through the seventh switch 328, and the second end of the second capacitor 325 is connected to the reset voltage source of the comparator 321 through the eighth switch 329.

[0074] Specifically, the fifth switch 326 may include a switch element S5 , the sixth switch 327 may include a switch element S6 , the seventh switch 328 may include a switch element S7 , and the eighth switch 329 may include a switch element S8 .

[0075] The reset voltage source can provide a voltage signal to the comparator 321 so that the input state of the comparator 321 is reset to a predefined state (usually resetting the two input terminals of the comparator 321 to the same voltage value), which helps to resume normal operation after the comparator 321 is restarted, the error state is restored, or a specific operation is completed.

[0076] Signal terminal V tem The first end of the capacitor C1 can be connected to the first end of the capacitor C1 through the switch element S5, and the second end of the capacitor C1 can be connected to the reset voltage source of the comparator 321 through the switch element S6. tem The first end of the capacitor C2 may be connected to the first end of the capacitor C2 via the switch element S7 , and the second end of the capacitor C2 may be connected to the reset voltage source of the comparator 321 via the switch element S8 .

[0077] When switch elements S5, S6, S7 and S8 are all closed, the first ends of capacitor elements C1 and C2 can be connected to the temperature voltage, and the second ends of capacitor elements C1 and C2 can be connected to the reset voltage of comparator 321, thereby achieving automatic resetting of comparator 321.

[0078] Reference Figure 6 In some embodiments, the temperature voltage acquisition circuit 100 includes at least two current sources 110 and at least two detection transistors 120. Each current source 110 is connected to the first electrode of the corresponding detection transistor 120, and the second electrode of each detection transistor 120 is grounded. The temperature voltage acquisition circuit 100 is configured to output a temperature voltage according to the first electrode voltage of at least one detection transistor 120.

[0079] Specifically, the temperature voltage acquisition circuit 100 may include a current source Ic1 and a current source Ic2, and the temperature voltage acquisition circuit 100 may include a transistor Q1 and a transistor Q2. The first electrode of the transistor Q1 may be connected to the current source Ic1, and the second electrode of the transistor Q1 may be grounded. The first electrode of the transistor Q2 may be connected to the current source Ic2, and the second electrode of the transistor Q2 may be grounded. The temperature voltage acquisition circuit 100 may determine the temperature voltage according to the output voltage of the first electrode of the transistor Q1, and may also determine the temperature voltage according to the output voltage of the first electrode of the transistor Q2.

[0080] Taking transistor Q1 as an example, the current source Ic1 can provide current I0, that is, the current flowing through transistor Q1 is current I0. When the operating parameters of transistor Q1 are determined, the temperature voltage parameters of transistor Q1 at current I0 can be determined, that is, the relationship between the voltage difference between the first electrode and the second electrode of transistor Q1 and the ambient temperature can be determined.

[0081] The transistor Q1 can be set as a bipolar transistor. The emitter of the transistor Q1 can be connected to the current source Ic1, the base of the transistor Q1 can be grounded, and the difference between the base and emitter voltages of the transistor Q1 is inversely proportional to the ambient temperature. When the temperature voltage parameter of the transistor Q1 is determined, the relationship between the emitter voltage of the transistor Q1 and the ambient temperature can be obtained. According to the collector current expression I of the bipolar transistor C =I S exp(V BE / V T ), where V T =kT / q, saturation current I S Proportional to Where μ is the mobility of minority carriers, n i is the intrinsic carrier concentration of silicon, and V BE =V T ln(I C / I S ), V BE It is a negative temperature coefficient voltage.

[0082] The implementation of the temperature voltage acquisition circuit 100 determining the temperature voltage according to the transistor Q2 can refer to the transistor Q1 and will not be described in detail here.

[0083] In some embodiments, at least two detection transistors 120 have the same voltage temperature coefficient, and the currents of the current sources 110 connected to the detection transistors 120 with the same voltage temperature coefficient are different.

[0084] Specifically, transistors Q1 and Q2 can be set to transistors with the same voltage temperature coefficient. The current provided by current source Ic1 is different from the current provided by current source Ic2, and the two transistors Q1 and Q2 can operate at unequal current densities. Current source Ic1 can provide current I0, and current source Ic2 can provide current nI0.

[0085] The temperature and voltage acquisition circuit 100 may include a switch element Sa, a switch element Sb, and a capacitor element Ca. The transistor Q1 may be connected to the capacitor element Ca via the switch element Sa. The transistor Q2 may be connected to the capacitor element Ca via the switch element Sb.

[0086] Capacitor Ca can collect the voltage of the first electrode of transistor Q1 to determine V BE1 The capacitor element Ca can also collect the first electrode voltage of the transistor Q2 to determine V BE2 .

[0087] In some embodiments, the temperature voltage acquisition circuit 100 includes a differential amplifier unit 130 , and the differential amplifier unit 130 is configured to output a temperature voltage according to a voltage difference between first electrode voltages of at least two detection transistors 120 .

[0088] The temperature detection circuit 1000 uses a double sampling technique to sample the temperature voltage signal on the bipolar transistor twice, and subtracts the two sampled voltage values, thereby eliminating the interference of low-frequency noise on the temperature voltage signal.

[0089] The capacitor element Ca can collect the voltage difference between the first electrode voltage of the transistor Q1 and the first electrode voltage of the transistor Q2 to determine the ambient temperature. S1 =I S2 ) are biased with collector currents I0 and nI0 respectively and ignoring their base currents, then

[0090] So, V BE The difference in temperature shows a positive temperature coefficient This temperature coefficient has nothing to do with temperature or the characteristics of the collector current. The voltage V obtained by this method is T It has high accuracy and is not affected by other factors, so that the determined ambient temperature has high accuracy.

[0091] The temperature and voltage acquisition circuit 100 may further include an operational amplifier A1, and a first input terminal of the operational amplifier A1 may be connected to the switch element Sa and the switch element Sb through a capacitor element Ca. The first input terminal of the operational amplifier A1 may also be connected to the signal terminal V tem0 The first input terminal of the operational amplifier A1 can also be connected to the signal terminal V tem0connect.

[0092] The differential amplifier unit 130 can collect the voltage difference between the first electrode voltages of at least two detection transistors 120, and provide the temperature voltage to the signal terminal V after differential amplification. tem0 .

[0093] The embodiment of the present application further provides an image sensor 2000 , which may include the temperature detection circuit of the above embodiment.

[0094] Reference Figure 7 The embodiment of the present application further provides a vehicle 10000 , and the vehicle 10000 may include the temperature detection circuit 1000 or the image sensor 2000 of the above embodiment.

[0095] In some embodiments, specifically, the temperature detection circuit 1000 can be used in various application scenarios that have precise temperature requirements, such as the image sensor 2000. Temperature detection is essential to ensure the performance, reliability and life of the image sensor. Through effective temperature management, the impact of temperature on image quality can be minimized, ensuring the good performance of the image sensor 2000 under various conditions.

[0096] In the description of this specification, the descriptions with reference to the terms "certain embodiments", "in an example", "exemplarily", etc., mean that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0097] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0098] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are optional and cannot be understood as limitations to the present application. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A temperature detection circuit, characterized in that: include: a temperature voltage acquisition circuit, configured to acquire a temperature voltage, wherein the temperature voltage is determined according to an ambient temperature of the temperature detection circuit; an addition and subtraction operation circuit connected to the temperature voltage acquisition circuit, configured to operate in a first mode or a second mode, wherein in the first mode, the addition and subtraction operation circuit is configured to process the temperature voltage and output a first voltage, and in the second mode, the addition and subtraction operation circuit is configured to process the temperature voltage and output a second voltage, wherein the first voltage is greater than the second voltage; The conversion quantization circuit connected to the addition and subtraction operation circuit is configured to determine the reference voltage value of the temperature detection circuit according to the first voltage, and is configured to determine the operating voltage value of the temperature detection circuit according to the second voltage.

2. The temperature detection circuit according to claim 1, characterized in that: The addition and subtraction operation circuit includes a first input terminal, a first operation branch, a second operation branch and a first output terminal; The first input terminal is configured to be connected to the temperature voltage. In the first mode, the first input terminal is connected to the first output terminal through the first operation branch. In the second mode, the first input terminal is connected to the first output terminal through the second operation branch.

3. The temperature detection circuit according to claim 2, characterized in that: The first operational branch includes a first operational amplifier, a positive connection branch, a negative connection branch, a feedback branch, an auxiliary voltage terminal and a first switch, and the auxiliary voltage terminal is configured to be connected to a predetermined auxiliary voltage; The positive input terminal of the first operational amplifier is connected to the first input terminal through the positive connecting branch, the negative input terminal of the first operational amplifier is connected to the auxiliary voltage terminal through the negative connecting branch, the negative input terminal is connected to the output terminal of the first operational amplifier through the feedback branch, and the output terminal of the first operational amplifier is connected to the first output terminal through the first switch.

4. The temperature detection circuit according to claim 3, characterized in that: The positive connection branch includes a first resistor and a second resistor, the positive input terminal of the first operational amplifier is connected to the first input terminal through the first resistor, and the positive input terminal of the first operational amplifier is grounded through the second resistor; The negative connection branch includes a third resistor, the feedback branch includes a fourth resistor, the auxiliary voltage terminal is connected to the negative input terminal of the first operational amplifier through the third resistor, and the negative input terminal of the first operational amplifier is connected to the output terminal of the first operational amplifier through the fourth resistor.

5. The temperature detection circuit according to claim 2, characterized in that: The second operation branch includes a second switch, and the first input end is connected to the first output end through the second switch.

6. The temperature detection circuit according to claim 1, characterized in that: The conversion quantization circuit comprises: A ramp generating circuit is configured to generate a ramp voltage signal; a comparator circuit connected to the ramp signal generating circuit and the addition and subtraction operation circuit, configured to determine a first identification signal according to the ramp voltage signal and the first voltage, and configured to determine a second identification signal according to the ramp voltage signal and the second voltage; The counter circuit connected to the comparator circuit is configured to determine the reference voltage value of the temperature detection circuit according to the first identification signal count, and is configured to determine the operating voltage value of the temperature detection circuit according to the second identification signal count.

7. The temperature detection circuit according to claim 6, characterized in that: The comparator circuit includes a comparator, a third switch and a fourth switch. The comparator includes a second input terminal, a third input terminal and a second output terminal. The second input terminal is connected to the ramp generating circuit through the third switch, the third input terminal is connected to the addition and subtraction operation circuit through the fourth switch, and the second output terminal is connected to the counter circuit.

8. The temperature detection circuit according to claim 7, characterized in that: The comparator circuit includes a first capacitor and a second capacitor. The first capacitor is connected between the third switch and the second input terminal, and the second capacitor is connected between the fourth switch and the third input terminal.

9. The temperature detection circuit according to claim 8, characterized in that: The comparator circuit also includes a fifth switch, a sixth switch, a seventh switch and an eighth switch, the first end of the first capacitor is connected to the addition and subtraction operation circuit through the fifth switch, the second end of the first capacitor is connected to the reset voltage source of the comparator through the sixth switch, the first end of the second capacitor is connected to the addition and subtraction operation circuit through the seventh switch, and the second end of the second capacitor is connected to the reset voltage source of the comparator through the eighth switch.

10. The temperature detection circuit according to claim 1, characterized in that: The temperature voltage acquisition circuit includes at least two current sources and at least two detection transistors, each of the current sources is connected to the first electrode of the corresponding detection transistor, and the second electrode of each detection transistor is grounded. The temperature voltage acquisition circuit is configured to output the temperature voltage according to the first electrode voltage of at least two detection transistors.

11. The temperature detection circuit according to claim 10, characterized in that: At least two of the detection transistors have the same voltage temperature coefficient, and the currents of the current sources connected to the detection transistors with the same voltage temperature coefficient are different.

12. The temperature detection circuit according to claim 10, characterized in that: The temperature voltage acquisition circuit includes a differential amplification unit, and the differential amplification unit is configured to output the temperature voltage according to a voltage difference between first electrode voltages of at least two detection transistors.

13. An image sensor, characterized in that: The image sensor comprises the temperature detection circuit according to any one of claims 1 to 12.

14. A vehicle, characterized in that: The vehicle comprises the temperature detection circuit according to any one of claims 1 to 12 or the image sensor according to claim 13.

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