Temperature compensation circuit

Abstract

The embodiment of the invention discloses a temperature compensation circuit. Wherein the first PTAT current generating circuit comprises a first resistor which is configured to output a first linear temperature compensation current with a first temperature coefficient; the second PTAT current generating circuit includes a second resistor configured to output a second linear temperature compensation current having a second temperature coefficient. The first temperature coefficient is different from the second temperature coefficient; and the resistance values of the first resistor and the second resistor are controlled to be equal to the current values of the first linear temperature compensation current and the second linear temperature compensation current at the set temperature. The comparison module is connected with the first PTAT current generation circuit and the second PTAT current generation circuit and is configured to compare the first linear temperature compensation current and the second linear temperature compensation current and output a comparison result. And the switching module is connected with the comparison module and is configured to output nonlinear temperature compensation current after changing the weighting proportion of the first linear temperature compensation current and the second linear temperature compensation current based on the comparison result.

Description

Technical Field

[0001] This application relates to integrated circuit technology, and to, but is not limited to, a temperature compensation circuit. Background Technology

[0002] In radio frequency and analog integrated circuit systems and modules, circuit temperature characteristics are crucial parameters. As temperature changes, circuits can generate linearly or non-linearly changing currents. Temperature sensors or temperature-compensated current circuits are needed to compensate for both linear and non-linear current changes, reducing the impact of temperature on circuit performance. Compensating for non-linear current changes is particularly challenging, requiring complex compensation circuits and resulting in less effective temperature compensation. Summary of the Invention

[0003] In view of this, the present application provides a temperature compensation circuit to solve at least one problem existing in the prior art. The temperature compensation current is obtained by weighting currents with different temperature compensation coefficients proportionally, thereby changing the slope of the nonlinear temperature compensation current. Moreover, the entire circuit structure is simple, occupies little space, and consumes little power.

[0004] The technical solution of this application embodiment is implemented as follows: This application provides a temperature compensation circuit. The temperature compensation circuit includes: a first PTAT current generating circuit, a second PTAT current generating circuit, a comparison module, and a switching module.

[0005] A first PTAT current generating circuit is configured to output a first linear temperature-compensated current with a first temperature coefficient. The first PTAT current generating circuit includes a first resistor for converting a temperature-proportional voltage into the first linear temperature-compensated current. A second PTAT current generating circuit is configured to output a second linear temperature-compensated current with a second temperature coefficient. The second PTAT current generating circuit includes a second resistor for converting a temperature-proportional voltage into the second linear temperature-compensated current. The first temperature coefficient and the second temperature coefficient are different. The resistance values ​​of the first resistor and the second resistor control the current values ​​of the first linear temperature-compensated current and the second linear temperature-compensated current, wherein, at a set temperature, the current values ​​of the first linear temperature-compensated current and the second linear temperature-compensated current are equal. A comparison module is connected to the first PTAT current generating circuit and the second PTAT current generating circuit, and is configured to compare the magnitudes of the first linear temperature-compensated current and the second linear temperature-compensated current, and output a comparison result. A switching module is connected to the output of the comparison module and is configured to, based on the comparison result, change the weighted ratio of the first linear temperature-compensated current and the second linear temperature-compensated current, and output a non-linear temperature-compensated current.

[0006] In the temperature compensation circuit, the first PTAT current generating circuit and the second PTAT current generating circuit generate a first linear temperature compensation current and a second linear temperature compensation current with different temperature coefficients, respectively. By comparing the first linear temperature compensation current and the second linear temperature compensation current, the output of the comparison module is triggered to flip. The output of the comparison module triggers the switching module to change the weighting ratio of the first linear temperature compensation current and the second linear temperature compensation current. This allows the current at the output of the switching module to exhibit different temperature characteristics at different temperatures, so that the temperature compensation current has different slopes as the temperature changes, thus achieving a nonlinear compensation current.

[0007] This solution eliminates the need for an external temperature sensor. By utilizing the temperature characteristics and dynamic switching mechanism of the first and second linear temperature compensation currents, it achieves switching of the temperature coefficient slope of the temperature compensation current, while simultaneously reducing circuit power consumption and area footprint.

[0008] The resistance values ​​of the first resistor and the second resistor control the current values ​​of the first linear temperature compensation current and the second linear temperature compensation current. At a set temperature, the current values ​​of the first linear temperature compensation current and the second linear temperature compensation current are equal. Therefore, the curves of the current of the first linear temperature compensation current and the second linear temperature compensation current changing with temperature intersect at the set temperature point. Automatic switching at the set temperature point is achieved through a comparator, which can realize seamless connection of temperature compensation current switching with different temperature coefficient slopes.

[0009] Switching modules to change the connection status includes two methods: First, the weighting coefficients of the first linear temperature-compensated current and the second linear temperature-compensated current in the switching module are 100% and 0%, or 0% and 100%, respectively. In other words, the switching module is configured such that connecting the output terminal of the switching module to the output terminal of the first PTAT current generation circuit or the output terminal of the second PTAT current generation circuit can easily realize the switching of current with two temperature coefficient slopes.

[0010] Second, the switching module is configured to change the weighting ratio of the first linear temperature compensation current and the second linear temperature compensation current. By using different weighting ratios, any combination of temperature coefficient slopes can be achieved, thereby improving the flexibility of adjusting the compensation current. Attached Figure Description

[0011] In the accompanying drawings, similar reference numerals may describe similar parts in different views. Similar reference numerals with different letter suffixes may indicate different examples of similar parts. The drawings illustrate, by way of example and not limitation, the various embodiments discussed herein.

[0012] Figure 1 A schematic diagram of a temperature compensation circuit is provided for some examples; Figure 2 for Figure 1 The diagram shows the temperature compensation circuit in which the two temperature compensation currents are equal at the set temperature value. Figure 3 for Figure 1 The diagram shows the actual output temperature compensation current and the target output temperature compensation current of the temperature compensation circuit. Figure 4 This is a schematic diagram of the structure of a temperature compensation circuit provided in an embodiment of this application; Figure 5A A schematic diagram showing the relationship between two linear temperature compensation currents with different temperature coefficients and temperature changes in the temperature compensation circuit provided in this embodiment of the application. Figure 5B for Figure 4 A schematic diagram showing the relationship between the nonlinear temperature compensation current output by the provided temperature compensation circuit and the temperature change. Figure 6 This is a schematic diagram of the structure of a temperature compensation circuit provided in an embodiment of this application; Figure 7A for Figure 6 A schematic diagram of the temperature compensation circuit in the first switch-on state; Figure 7B for Figure 6 A schematic diagram of the provided temperature compensation circuit in the second switch-on state; Figure 8 for Figure 6 A schematic diagram of another switching module of the provided temperature compensation circuit; Figure 9A for Figure 8 A schematic diagram of the provided temperature compensation circuit with both the third and fourth switches on. Figure 9B for Figure 8 A schematic diagram of the temperature compensation circuit with both the fifth and sixth switches on. Figure 9C for Figure 6 A schematic diagram of another switching module of the provided temperature compensation circuit; Figure 10 for Figure 8 A schematic diagram showing the relationship between the nonlinear temperature compensation current output by the provided temperature compensation circuit and the temperature change. Figure 11 for Figure 6 A schematic diagram of another first PTAT current generating circuit and a second PTAT current generating circuit provided for the temperature compensation circuit. Figure 12 for Figure 6The diagram shows another unidirectional conduction unit of the first PTAT current generating circuit and the second PTAT current generating circuit. Figure 13 for Figure 6 A schematic diagram of another comparison module provided for the temperature compensation circuit; Figure 14 (a) and (b) are schematic diagrams of the structures of two comparators provided in the embodiments of this application. Detailed Implementation

[0013] The technical solution of this application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0014] In the embodiments of this application, the terms "first," "second," etc., are used to distinguish similar objects, and not to describe a specific order or sequence.

[0015] It should be understood that the phrases "some embodiments" or "some examples" mentioned throughout the specification mean that a specific feature, structure, or characteristic related to an embodiment is included in at least one embodiment of this application. Therefore, "some embodiments" or "some examples" appearing throughout the specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It should be understood that in the various embodiments of this application, the sequence number of each process does not imply the order of execution; the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application. The sequence numbers of the embodiments in this application are merely descriptive and do not represent the superiority or inferiority of the embodiments.

[0016] It should be noted that, in this document, 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. Unless otherwise specified, 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 that element.

[0017] It should be noted that although this specification describes the embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0018] In RF and analog integrated circuit systems and modules, circuit temperature characteristics are a crucial parameter. For example, inconsistent gain temperature drift in the receiver link can cause changes in sensitivity and dynamic range at different temperatures; inconsistent gain temperature drift in the transmitter link may lead to a deterioration of the gain vector amplitude (EVM) at different temperatures; inconsistent gain temperature drift in the detector link can lead to increased detection errors at different temperatures; and inconsistent oscillator frequency temperature drift can cause phase-locked loop (PLL) loss of lock-in.

[0019] Therefore, it is usually necessary to ensure that the circuit characteristics remain consistent with temperature changes (of course, there may be some special scenarios where specific temperature change characteristics need to be maintained). However, since the active devices that make up the circuit usually change with temperature, temperature compensation circuits are usually needed to correct the changes in circuit temperature characteristics caused by changes in device parameters.

[0020] Temperature compensation circuits are generally divided into linear temperature compensation and nonlinear temperature compensation. Because linear temperature compensation is simpler and easier to implement, it is usually used in scenarios where the temperature compensation current requirement is not high. However, for scenarios with higher temperature compensation current requirements (such as those where the temperature change may be nonlinear), nonlinear temperature compensation is crucial. Compared to linear temperature compensation, nonlinear temperature compensation allows the gain to remain consistent over a wider temperature range. However, it is technically more difficult and has a more complex circuit structure.

[0021] For example, such as Figure 1 As shown, a nonlinear temperature compensation circuit includes two temperature-compensated current output circuits with different temperature characteristics (the linear temperature-compensated currents IPTAT1 and IPTAT2 output by the two circuits have different slopes as temperature changes), a multiplexer, and a temperature sensor. One temperature-compensated current output circuit includes transistors M1-M3, an amplifier, transistors Q1 and Q2, and a resistor RT1; the other temperature-compensated current output circuit includes transistors M4-M6, an amplifier, transistors Q3 and Q4, and a resistor RT2. The temperature of the circuit is sensed by the temperature sensor. When the temperature is lower than the temperature value T, the temperature sensor generates a control signal to control the multiplexer, which selects IPTAT1 as the output. When the temperature reaches and exceeds the temperature value T, the temperature sensor generates another control signal, which selects IPTAT2 as the output through the multiplexer, thus switching the temperature-compensated current IPTAT.

[0022] In the case of temperature-compensated current output circuits based on two different temperature characteristics, to ensure that the temperature-compensated currents output by the two circuits are equal at a certain temperature T, it is necessary to calibrate and match the slopes of the linear temperature-compensated currents IPTAT1 and IPTAT2 output by the two circuits as a function of temperature. For example, if the slopes of the temperature-compensated currents IPTAT1 and IPTAT2 as a function of temperature are not calibrated and matched, such as... Figure 2 As shown in (a), the curves of IPTAT1 and IPTAT2 changing with temperature do not intersect at temperature T. At temperature T, the magnitudes of the temperature compensation currents IPTAT1 and IPTAT2 are not equal. If current switching is performed, current jumps will occur, affecting the accuracy and reliability of temperature compensation.

[0023] Therefore, please refer to the following: Figure 1 In the temperature-compensated current output circuit of IPTAT1, the positive input terminal of the amplifier is connected to the reference voltage VBG, and the negative input terminal is connected to the output terminal of the amplifier, forming a negative feedback circuit. Transistors M7 and M8 form a current mirror. The output terminal of the amplifier is connected to one end of the thermistor RT3 and then to the output terminal of transistor M7. The output terminal of transistor M8 is connected to the output terminal of transistor M3. Through this structure, the current at the output terminal of transistor M8 compensates for the current at the output terminal of transistor M3, thereby increasing the magnitude of the temperature-compensated current IPTAT1. Figure 2 As shown in (b), the curves of IPTAT1 and IPTAT2 after compensation as a function of temperature can intersect, which can improve the accuracy of temperature compensation.

[0024] However, the inventors discovered that by setting up an external multiplexer and temperature sensor for the temperature-compensated current output circuit, the circuit structure of the multiplexer and temperature sensor occupies a large space, which is not conducive to reducing the size of the entire integrated circuit structure of the output nonlinear temperature-compensated current, and the power consumption is large. Moreover, the temperature sensor has limited accuracy in sensing temperature changes, making it difficult to switch precisely at the theoretical intersection temperature value T, which easily leads to temperature-compensated current connection problems.

[0025] For example, such as Figure 3 As shown in (a), because the slopes of the two linear temperature-compensated currents IPTAT1 and IPTAT2 change with temperature are different, when the two linear temperature-compensated currents IPTAT1 and IPTAT2 are combined, a nonlinear temperature-compensated current is ultimately generated. However, when the two linear temperature-compensated currents IPTAT1 and IPTAT2 are combined at temperature T, the target temperature-compensated current (such as...) Figure 3 (d) shown in the figure) and the actual temperature compensation current (as shown in the figure) Figure 3 The differences shown in (b) or (c) are significant, which seriously affects the accuracy and reliability of temperature compensation.

[0026] For example, such as Figure 3 As shown in (b), the temperature value sensed by the temperature sensor is greater than the actual temperature value T at the intersection of the linear temperature compensation currents IPTAT1 and IPTAT2. Therefore, the multiplexer will delay switching IPTAT1 to IPTAT2. Combined with... Figure 3 The linear temperature compensation currents IPTAT1 and IPTAT2 shown in (a) are related to the temperature value T. When the temperature is greater than T, the output nonlinear temperature compensation current IPTAT increases sharply from the current value IPTAT1 to the current value IPTAT2.

[0027] For example, such as Figure 3 As shown in (c), the temperature value sensed by the temperature sensor is less than the actual temperature value T at the intersection of the linear temperature compensation currents IPTAT1 and IPTAT2. The multiplexer will switch IPTAT1 to IPTAT2 prematurely. Combined with... Figure 3 The linear temperature-compensated currents IPTAT1 and IPTAT2 shown in (a) are related to the temperature value T. When the temperature is less than T, the output nonlinear temperature-compensated current IPTAT drops sharply from the current value IPTAT1 to the current value IPTAT2.

[0028] To address this issue, this application provides a temperature compensation circuit that eliminates the need for a temperature sensor. This circuit, through an integrated comparison and switching module, automatically and accurately selects or mixes different temperature compensation currents based on the comparison results of its internal branches. The entire circuit has a simple structure, occupies less space, and consumes less power.

[0029] In some examples, such as Figure 4 As shown, the temperature compensation circuit 100 includes: a first PTAT current generating circuit 110, a second PTAT current generating circuit 120, a comparison module 130, and a switching module 140. Both the first PTAT current generating circuit 110 and the second PTAT current generating circuit 120 are PTAT (Proportional To Absolute Temperature) current generating circuits, generating a voltage proportional to temperature.

[0030] The first PTAT current generating circuit 110 includes a first resistor R1, which is used to convert a voltage proportional to temperature into a first linear temperature-compensated current I. C1 The first PTAT current generating circuit 110 outputs a first linear temperature-compensated current I with a first temperature coefficient. C1 The first linear temperature-compensated current I C1 Its magnitude changes linearly with temperature.

[0031] The second PTAT current generating circuit 120 includes a second resistor R2, which is used to convert a temperature-proportional voltage into a second linear temperature-compensated current I. C2 The output terminal of the second PTAT current generating circuit 120 outputs a second linear temperature-compensated current I with a second temperature coefficient. C2 The second linear temperature-compensated current I C2 The magnitude of the temperature coefficient changes linearly with temperature; the first temperature coefficient is different from the second temperature coefficient. The resistance values ​​of the first resistor R1 and the second resistor R2 control the first linear temperature compensation current I. C1 With the second linear temperature compensation current I C2 The current value, wherein, at the set temperature, the first linear temperature-compensated current I C1 With the second linear temperature compensation current I C2 The current values ​​are equal.

[0032] Understandably, the temperature coefficient is a parameter used to describe the degree to which current or resistance changes with temperature; it is expressed as the relative rate of change of current or resistance caused by a unit change in temperature. The temperature coefficient of resistance is expressed as the relative rate of change of resistance caused by a unit change in temperature. The temperature coefficient of current is expressed as the relative rate of change of current caused by a unit change in temperature. Based on the difference in temperature coefficients between the first resistor R1 and the second resistor R2, the first linear temperature-compensated current I... C1 Second linear temperature-compensated current I C2 The slope varies with temperature, providing a basis for subsequent nonlinear compensation through comparison module 130 and switching module 140.

[0033] Continue reading Figure 4 The two signal input terminals of the comparison module 130 are respectively connected to the output terminals of the first PTAT current generation circuit 110 and the second PTAT current generation circuit 120, and are configured to compare the first linear temperature-compensated current I. C1 Second linear temperature-compensated current I C2 The size of I is used to output the comparison result. For example, when I C1 C2 When I, the comparison module 130 outputs the first comparison result; when I C1 ≥I C2 At that time, comparison module 130 outputs the second comparison result. For example, as... Figure 4 ​As shown, the switching module 140 requires two control signals to switch or mix. Therefore, the comparison result output by the comparison module 130 includes a first control signal Ctrl1 and a second control signal Ctrl2. The first control signal Ctrl1 and the second control signal Ctrl2 can be inverse signals. When the first control signal Ctrl1 is 1, the second control signal Ctrl2 is 0; when the first control signal Ctrl1 is 0, the second control signal Ctrl2 is 1.

[0034] Continue reading Figure 4 The switching module 140 includes an input terminal connected to the first PTAT current generating circuit 110, an input terminal connected to the second PTAT current generating circuit 120, two input terminals respectively connected to the two output terminals of the comparison module 130, and an output terminal connected to the output terminal of the entire temperature compensation circuit 100. For example, the input terminal of the switching module 140 connected to the first PTAT current generating circuit 110 is configured to receive a first linear temperature compensation current I transmitted from the output terminal of the third transistor T3. C1 The input terminal of the switching module 140, which is connected to the second PTAT current generating circuit 120, is configured to receive the second linear temperature-compensated current I transmitted from the output terminal of the sixth transistor T6. C2 The two input terminals connected to the two output terminals of the switching module 140 and the comparison module 130 are configured to receive different control signals. The output terminal of the switching module 140 is configured to output a first linear temperature-compensated current I. C1 Second linear temperature-compensated current I C2 The weighted sum.

[0035] For example, the control terminal of the switching module 140 is connected to the output terminal of the comparison module 130 and configured to: change the first linear temperature compensation current I based on the comparison result (e.g., the first control signal Ctrl1 and the second control signal Ctrl2). C1 Second linear temperature-compensated current I C2 After weighting, the output nonlinear temperature compensation current I is obtained. C For example, when the comparison module 130 outputs the first comparison result, the temperature compensation current I at the output of the switching module 140 is switched. C For: a1 × First linear temperature-compensated current I C1 +a2×Second linear temperature compensation current I C2 (Formula 1); or, when the comparison module 130 outputs the second comparison result, the temperature compensation current I at the output of the switching module 140 is switched. C For: b1 × first linear temperature compensation current I C1 +b2×Second linear temperature compensation current I C2(Formula 2), where a1:a2≠b1:b2, and a1, a2, b1, and b2 are weighted ratios. Then, the first linear temperature-compensated current I... C1 Second linear temperature-compensated current I C2 The weighted current is output to the output terminal of the temperature compensation circuit 100 (output terminal of the switching module 140).

[0036] Thus, in the temperature compensation circuit 100, the first PTAT current generating circuit 110 and the second PTAT current generating circuit 120 respectively generate a first linear temperature compensation current I with different temperature coefficients. C1 Second linear temperature-compensated current I C2 (See also) Figure 5A By setting the resistance values ​​of the first resistor R1 and the second resistor R2 at a set temperature, the first linear temperature-compensated current I is such that at that set temperature... C1 Second linear temperature-compensated current I C2 They are equal. Therefore, when the temperature changes to the set temperature, the first linear temperature compensation current I is compared through the comparison module 130. C1 Second linear temperature-compensated current I C2 The magnitude triggers the comparator in the comparison module 130 to flip, and changes the first linear temperature compensation current I through the switching module 140. C1 Second linear temperature-compensated current I C2 The weighting ratio can adjust the temperature compensation current I at the output of the switching module 140. C It exhibits different temperature characteristics at different temperatures, realizing a nonlinear temperature compensation current I. C .

[0037] Specifically, at the set temperature point, the first linear temperature compensation current I C1 With the second linear temperature compensation current I C2 The current values ​​are equal, which means that the first linear temperature-compensated current I C1 With the second linear temperature compensation current I C2 The circuit exhibits the same current value at this temperature point. Therefore, when the circuit switches at this temperature point, it can achieve seamless connection between temperature-compensated currents with different temperature coefficients, avoiding the current jump problem caused by switching in traditional solutions.

[0038] Furthermore, this solution does not require an external temperature sensor, as it utilizes the first linear temperature compensation current I... C1 Second linear temperature-compensated current I C2 The temperature characteristics and dynamic switching mechanism enable switching between different temperature zones with varying slopes, while simultaneously reducing circuit power consumption and footprint.

[0039] It should be noted that the "set temperature point" corresponds to the inflection point where the slope of the current to be compensated for changes significantly with temperature, i.e., the boundary temperature between two different temperature response ranges. This "set temperature point" can be set according to the characteristic requirements of different currents to be compensated for.

[0040] In some examples, the first resistor R1 and the second resistor R2 can be set as thermistors, and their temperature coefficients and resistance values ​​can be adjusted by setting parameters such as their dimensions (e.g., aspect ratio) and materials (e.g., polycrystalline silicon resistors). The specific dimensions and materials set can be adjusted according to actual conditions, and the examples provided in this application do not impose specific limitations on this.

[0041] For example, the first resistor R1 and the second resistor R2 are thermistors with different temperature coefficients. For instance, both the first resistor R1 and the second resistor R2 are resistors with a positive temperature coefficient; however, the positive temperature coefficient of the first resistor R1 is smaller than that of the second resistor R2. That is, the rate of change of the resistance of the first resistor R1 with temperature is less than the rate of change of the resistance of the second resistor R2 with temperature. Thus, the rates of change of the resistance of the first resistor R1 with temperature are different from those of the resistance of the second resistor R2 with temperature.

[0042] For example, such as Figure 5A As shown, the rate of decrease in resistance of the first resistor R1 with increasing temperature is less than the rate of decrease in resistance of the second resistor R2 with increasing temperature, characterizing the first linear temperature-compensated current I transmitted by the first PTAT current generating circuit 110. C1 The rate of change that increases with increasing temperature is less than the second linear temperature-compensated current I transmitted by the second PTAT current generating circuit 120. C2 The rate of change that increases with increasing temperature.

[0043] For example, both the first resistor R1 and the second resistor R2 are resistors with negative temperature coefficients; and the negative temperature coefficient of the first resistor R1 is greater than that of the second resistor R2, that is, the rate of change of the resistance value of the first resistor R1 with temperature is greater than the rate of change of the resistance value of the second resistor R2 with temperature.

[0044] For example, the first resistor R1 is a resistor with zero temperature coefficient, and the second resistor R2 is a resistor with positive or negative temperature coefficient, so that it is easier to set the relationship between the resistance values ​​of the second resistor R2 and the first resistor R1 at a certain set temperature point Ta.

[0045] In this way, by setting the rates of change of the resistance value of the first resistor R1 with temperature to be different from those of the resistance value of the second resistor R2 with temperature, it is possible to achieve the following: Figure 5A The first linear temperature-compensated current I shown C1 Second linear temperature-compensated current I C2 The current values ​​at the set temperature point Ta are equal. Therefore, the comparison result of the comparator in the comparison module 130 flips, triggering the switching module 140 to switch. Since the currents transmitted by the first PTAT current generating circuit 110 and the second PTAT current generating circuit 120 are continuous at the set temperature point Ta before and after the switch, a smooth and seamless transition of the nonlinear temperature-compensated current can be achieved (e.g., ...). Figure 5B This can improve the temperature compensation current accuracy of the temperature compensation circuit 100.

[0046] This application does not impose any restrictions on this, and adjustments can be made according to the changes in temperature compensation current required by the actual application scenario.

[0047] The following example illustrates the use of a first PTAT current generating circuit 110 and a second PTAT current generating circuit 120 as exemplary illustrations of temperature-compensated current generation circuits for PTAT current generation.

[0048] In some examples, such as Figure 6 As shown, the first PTAT current generating circuit 110 includes a first resistor R1, a first current mirror, a first unidirectional conduction unit U1, and a second unidirectional conduction unit U2.

[0049] Specifically, the first current mirror includes a first transistor T1, a second transistor T2, and a third transistor T3. The control terminals of the first transistor T1 to the third transistor T3 are all connected together. The input terminals (sources) of the first transistor T1 to the third transistor T3 are all connected to the first power supply voltage terminal (e.g., VDD). The second transistor T2 and the third transistor T3 replicate the current flowing through the first transistor T1 in a certain proportion. The first terminal of the first unidirectional conduction unit U1 is connected to the output terminal of the first transistor T1, and the second terminal of the first unidirectional conduction unit U1 is connected to the second power supply voltage terminal (e.g., ground). The first terminal of the second unidirectional conduction unit U2 is connected to the output terminal of the second transistor T2, and the second terminal of the second unidirectional conduction unit U2 is connected to the second power supply voltage terminal (e.g., ground).

[0050] exist Figure 6In the circuit, the first PTAT current generating circuit 110 also includes a first amplifier 111. The output terminal of the first transistor T1 is connected to the first input terminal (e.g., the inverting input terminal) of the first amplifier 111, and the output terminal of the second transistor T2 is connected to the second input terminal (e.g., the non-inverting input terminal) of the first amplifier 111. The output terminal of the first amplifier 111 is connected to the control terminal of the first transistor T1, thereby forming a negative feedback loop together with the first transistor T1 and the second transistor T2 to clamp the voltage between the first input terminal and the second input terminal, so that the voltage at the output terminal of the first transistor T1 is equal to the voltage at the output terminal of the second transistor T2.

[0051] Understandably, a unidirectional conducting unit can be a diode or a transistor connected in diode form, which achieves unidirectional conduction under forward bias. For example, the second transistor T2 replicates the current of the first transistor T1, so the current flowing through the first unidirectional conducting unit U1 and the second unidirectional conducting unit U2 is the same. The first unidirectional conducting unit U1 and the second unidirectional conducting unit U2 have different dimensions, resulting in a difference in their forward voltage drops, forming a voltage difference ΔV. Since the unidirectional conducting unit itself has a temperature coefficient, this voltage difference... V is a voltage with a positive temperature coefficient; and the voltages at the output terminals of the first transistor T1 (node ​​N2) and the second transistor T2 (node ​​N1) are equal, therefore the voltage across the first resistor R1 is the voltage difference. V, voltage difference with temperature coefficient A current V is applied across the first resistor R1, forming a current with a positive temperature coefficient. Therefore, the current flowing through the second transistor T2 is also a current with a positive temperature coefficient. The current in the first transistor T1 is equal to the current in the second transistor T2, making the current flowing through the first transistor T1 a current with a positive temperature coefficient. When the unidirectional conducting unit can be a diode, its size is the area of ​​the PN junction; when the unidirectional conducting unit can be a transistor connected in a diode configuration, its size is the aspect ratio of the transistor's gate (the ratio of gate length to gate width).

[0052] The third transistor T3 replicates the current of the first transistor T1 by a certain ratio, therefore the output terminal of the third transistor T3 outputs the first linear temperature-compensated current I. C1 The first linear temperature-compensated current I C1 It has the same temperature characteristics as the first transistor T1 current.

[0053] Continue reading Figure 6 The second PTAT current generating circuit 120 includes a second resistor R2, a second current mirror, a third unidirectional conduction unit U3, and a fourth unidirectional conduction unit U4.

[0054] Specifically, the second current mirror includes a fourth transistor T4, a fifth transistor T5, and a sixth transistor T6. The control terminals of transistors T4 to T6 are all connected together. The input terminals (sources) of transistors T4 to T6 are all connected to a first power supply voltage terminal (e.g., VDD). Transistors T5 and T6 replicate the current flowing through the first transistor T1 in a certain proportion. One end of the third unidirectional conducting unit U3 is connected to the output terminal of the fourth transistor T4, and the other end of the third unidirectional conducting unit U3 is connected to a second power supply voltage terminal (e.g., ground). One end of the fourth unidirectional conducting unit U4 is connected to the output terminal of the fifth transistor T5, and the other end of the fourth unidirectional conducting unit U4 is connected to a second power supply voltage terminal (e.g., ground). In some embodiments, the third unidirectional conducting unit U3 and the fourth unidirectional conducting unit U4 have different dimensions, generating a positive temperature coefficient voltage. This voltage is applied to the second resistor R2, forming a positive temperature coefficient current. Through the current replication of the second current mirror, the current flowing through the fourth transistor T4 is a positive temperature coefficient current.

[0055] exist Figure 6 In the second PTAT current generating circuit 120, there is also a second amplifier 121. The output terminal of the fourth transistor T4 is connected to the first input terminal (e.g., the inverting input terminal) of the second amplifier 121, and the output terminal of the fifth transistor T5 is connected to the second input terminal (e.g., the non-inverting input terminal) of the second amplifier 121. The output terminal of the second amplifier 121 is connected to the control terminal of the fourth transistor T4, so that together with the fourth transistor T4 and the fifth transistor T5 / sixth transistor T6, a negative feedback loop is formed to clamp the voltage between the first input terminal and the second input terminal.

[0056] The sixth transistor T6 replicates the current of the fourth transistor T4 at a certain ratio, therefore the output of the sixth transistor T6 outputs the second linear temperature-compensated current I. C2 The second linear temperature-compensated current I C2 The temperature coefficient is equal to the temperature coefficient of the current of the fourth transistor T4.

[0057] The first PTAT current generating circuit 110 and the second PTAT current generating circuit 120 are independent of each other, and the first transistor T1 and the fourth transistor T4 are not shared, so that the first PTAT current generating circuit 110 and the second PTAT current generating circuit 120 can independently generate their respective temperature compensation currents.

[0058] In some embodiments, the dimensions of the first transistor T1 are equal to those of the fourth transistor T4, the dimensions of the second transistor T2 are equal to those of the fifth transistor T5, and the dimensions of the third transistor are equal to those of the sixth transistor. Thus, the corresponding transistors in the first and second current mirrors form a matched size, ensuring that the current replication ratios of the second transistor T2 and the fifth transistor T5 are the same, and the current replication ratios of the third transistor T3 and the sixth transistor T6 are the same. This symmetrical design helps ensure the first linear temperature-compensated current I... C1 With the second linear temperature compensation current I C2 The current magnitude remains consistent at the set temperature to avoid current jumps during current switching. In other embodiments, the dimensions of the first transistor T1 to the sixth transistor T6 can also be set to other dimensions and proportions.

[0059] The size difference between the first unidirectional conducting unit U1 and the second unidirectional conducting unit U2 affects the voltage difference between the two ends of the first unidirectional conducting unit U1 and the second unidirectional conducting unit U2. V, thus affecting the magnitude of the current flowing through the first resistor R1, and the current flowing through the first resistor R1 is related to the first linear temperature-compensated current I. C1 The size difference between the first unidirectional conducting unit U1 and the second unidirectional conducting unit U2 is proportional to the first linear temperature-compensated current I. C1 The size of the second linear temperature-compensated current I is also affected by the size difference between the third unidirectional conduction unit U3 and the fourth unidirectional conduction unit U4. C2 The size of the first unidirectional conducting unit U1 and the third unidirectional conducting unit U3 can be set to be the same to facilitate a smooth transition and seamless connection between the two linear temperature compensation currents before and after switching at the set temperature point T. This ensures that the first linear temperature compensation current I... C1 Second linear temperature-compensated current I C2 The reference standards are consistent, which facilitates the setting of the first resistor R1 and the second resistor R2. Therefore, the second unidirectional conduction unit U2, the fourth unidirectional conduction unit U4, the first resistor R1, and the second resistor R2 satisfy the following relationship: 1) If the size of the second unidirectional conducting unit U2 is equal to the size of the fourth unidirectional conducting unit U4, then the resistance values ​​of the first resistor R1 and the second resistor R2 are equal at the set temperature point Ta. Because the size of the second unidirectional conducting unit U2 is equal to the size of the fourth unidirectional conducting unit U4, the second unidirectional conducting unit U2 provides resistance to the first linear temperature-compensated current I. C1 The influence of the fourth unidirectional conduction unit U4 on the second linear temperature compensation current I C2 The effect is consistent; if the first resistor R1 and the second resistor R2 are not set, then the first linear temperature-compensated current I... C1 With the second linear temperature compensation current I C2The temperature coefficients are the same. Because the temperature coefficients of the first resistor R1 and the second resistor R2 are different, the rates of change of the resistance of the first resistor R1 with temperature and the rates of change of the resistance of the second resistor R2 with temperature are different. At the temperature corresponding to the intersection of the first and second temperature curves (i.e., the set temperature point Ta), the resistance of the first resistor R1 and the resistance of the second resistor R2 are equal, characterized as follows: Figure 5A The first linear temperature-compensated current I shown C1 Second linear temperature-compensated current I C2 At a fixed temperature point Ta, the current values ​​are equal, and the input currents across comparator 133 are exactly equal. This causes the comparator's comparison result to flip, triggering the switching module 140 to perform a switch. Because the two first linear temperature-compensated currents I before and after the switch... C1 With the second linear temperature compensation current I C2 Since the temperature point Ta is continuous, it is possible to achieve a smooth and seamless connection of the nonlinear temperature compensation current. 2) If the size of the second unidirectional conducting unit U2 is larger than the size of the fourth unidirectional conducting unit U4, then at the set temperature point, the resistance of the first resistor R1 is greater than the resistance of the second resistor R2. Since the size of the second unidirectional conducting unit U2 is larger than the size of the fourth unidirectional conducting unit U4, if the first resistor R1 and the second resistor R2 are not set, then the first linear temperature-compensated current I... C1 The temperature coefficient is greater than the second linear temperature compensation current I. C2 The temperature coefficient. Therefore, at the set temperature point, the resistance of the first resistor R1 is greater than the resistance of the second resistor R2, and the first resistor R1 can reduce the first linear temperature compensation current I. C1 This is to achieve a smooth transition and seamless connection of the transmission current of the two branches before and after switching at the set temperature point Ta; 3) If the size of the second unidirectional conducting unit U2 is smaller than the size of the fourth unidirectional conducting unit U4, then at the set temperature point, the resistance of the first resistor R1 is smaller than the resistance of the second resistor R2. Since the size of the second unidirectional conducting unit U2 is smaller than the size of the fourth unidirectional conducting unit U4, if the first resistor R1 and the second resistor R2 are not set, then the first linear temperature-compensated current I... C1 The temperature coefficient is less than that of the second linear temperature-compensated current I C2 The temperature coefficient. At the set temperature point, the resistance of the first resistor R1 is less than the resistance of the second resistor R2, and the second resistor R2 can reduce the second linear temperature compensation current I. C2 This is to achieve a smooth transition and seamless connection of the transmission current of the two branches before and after switching at the set temperature point Ta.

[0060] In some examples, such as Figure 6As shown, the first unidirectional conduction unit U1 includes a ninth transistor T9, which is a PNP transistor. The first terminal of the ninth transistor T9 is connected to the inverting input terminal of the first amplifier 111, the second terminal of the ninth transistor T9 is grounded, and the control terminal of the ninth transistor T9 is connected to the second terminal of the ninth transistor T9 (i.e., grounded), forming a diode connection.

[0061] The second unidirectional conduction unit U2 includes a tenth transistor T10, which is a PNP transistor. The first terminal of the tenth transistor T10 is connected to one end of the first resistor R1, the second terminal of the tenth transistor T10 is grounded, and the control terminal of the tenth transistor T10 is connected to the second terminal of the tenth transistor T10 (i.e., grounded), forming a diode connection.

[0062] The third unidirectional conduction unit U3 includes an eleventh transistor T11, which is a PNP transistor. The first terminal of the eleventh transistor T11 is connected to the inverting input terminal of the second amplifier 121, the second terminal of the eleventh transistor T11 is grounded, and the control terminal of the eleventh transistor T11 is connected to the second terminal of the eleventh transistor T11 (i.e., grounded), forming a diode connection.

[0063] The fourth unidirectional conduction unit U4 includes a twelfth transistor T12, which is a PNP transistor. The first terminal of the twelfth transistor T12 is connected to one end of the second resistor R2, the second terminal of the twelfth transistor T12 is grounded, and the control terminal of the twelfth transistor T12 is connected to the second terminal of the twelfth transistor T12 (i.e., grounded), forming a diode connection.

[0064] It should be noted that the "first terminal" of a transistor can be the emitter, the "second terminal" can be the collector, and the "control terminal" can be the base; or, the "first terminal" can be the collector, the "second terminal" can be the emitter, and the "control terminal" can be the base. The examples provided in this application do not impose specific limitations on the "first terminal" and the "second terminal," and these can be adjusted according to different transistor types.

[0065] In some examples, the first amplifier 111 and the second amplifier 121 may include at least one of a five-tube amplifier, a sleeve amplifier, and a folded amplifier. The examples provided in this application are not limiting and can be selected according to actual needs.

[0066] like Figure 6 As shown, in some examples, the temperature compensation circuit 100 further includes a first current replication unit 150 and a second current replication unit 160. The first current replication unit 150 is connected to the first PTAT current generation circuit 110 and is configured to replicate the first linear temperature compensation current I. C1By introducing an independent replication path, the replicated current is provided to the comparison module 130 for comparison, avoiding direct comparison of the first linear temperature-compensated current I. C1 It generates noise. For example, such as... Figure 6 As shown, the first current replication unit 150 includes a seventh transistor T7. The control terminal of the seventh transistor T7 is connected to the control terminal of the first transistor T1, and the input terminals of the seventh transistor T7, the first transistor T1 (and the second transistor T2 and the third transistor T3) are all connected to the same power supply voltage terminal (e.g., VDD). Thus, the seventh transistor T7 and the first transistor T1 are included in a current mirror structure, replicating the current flowing through the first transistor T1 according to a preset ratio, such that the current output from the output terminal of the seventh transistor T7 is similar to the first linear temperature-compensated current I. C1 Proportional. The structure of the first current replication unit 150 is not limited to... Figure 6 The structure shown can also employ cascode current mirrors, Wilson current mirrors, etc.

[0067] The second current replication unit 160 is connected to the second PTAT current generation circuit 120 and is configured to replicate the second linear temperature-compensated current I. C2 By introducing an independent replication path, the replicated current is provided to the comparison module 130 for comparison, avoiding direct comparison of the second linear temperature-compensated current I. C2 It generates noise. For example, such as... Figure 6 As shown, the second current replication unit 160 includes an eighth transistor T8. The control terminal of the eighth transistor T8 is connected to the control terminal of the fourth transistor T4, and the input terminals of the eighth transistor T8 and the fourth transistor T4 (as well as the input terminals of the fifth transistor T5 and the sixth transistor T6) are all connected to the same power supply voltage terminal (e.g., VDD). Thus, the eighth transistor T8 and the fourth transistor T4 are included in a current mirror structure, replicating the current flowing through the fourth transistor T4 according to a preset ratio, such that the current output from the output terminal of the eighth transistor T8 is similar to the second linear temperature-compensated current I. C2 Proportional. The structure of the second current replication unit 160 is not limited to... Figure 6 The structure shown can also employ cascode current mirrors, Wilson current mirrors, etc.

[0068] Comparison module 130, connected to the output terminal of the first current replication unit 150 (output terminal of the seventh transistor T7) and the output terminal of the second current replication unit 160 (output terminal of the eighth transistor T8), is configured to replicate the first linear temperature-compensated current I. C1 and the replicated second linear temperature-compensated current I C2 Compare them.

[0069] In some embodiments, the first current replication unit 150 and the second current replication unit 160 replicate the first linear temperature-compensated current I at a 1:1 ratio. C1 Second linear temperature-compensated current I C2 To ensure that the replicated current accurately reflects the first linear temperature-compensated current I C1 Second linear temperature-compensated current I C2 This ensures the accuracy of subsequent comparisons. For example, the dimensions of the seventh transistor T7 and the third transistor T3 can be set to be the same (the aspect ratios of the transistors are the same). This indicates that the threshold voltages of the seventh transistor T7 and the third transistor T3 are equal, meaning that the currents transferred by the seventh transistor T7 and the third transistor T3 are equal. The current in the seventh transistor T7 is equal to the first linear temperature-compensated current I. C1 The dimensions of the eighth transistor T8 and the sixth transistor T6 can be set to be the same (the aspect ratios of the transistors are the same). This indicates that the threshold voltages of the eighth transistor T8 and the sixth transistor T6 are equal, and therefore the currents transferred by the eighth transistor T8 and the sixth transistor T6 are equal. The current of the eighth transistor T8 is equal to the second linear temperature-compensated current I. C2 .

[0070] In some examples, such as Figure 6 As shown, the comparison module 130 in the temperature compensation circuit 100 includes a first voltage conversion circuit 131, a second voltage conversion circuit 132, and a comparator 133; wherein, the comparator 133 is a voltage comparator used to compare voltages, so the first voltage conversion circuit 131 and the second voltage conversion circuit 132 first need to convert the current into voltage so that the comparator 133 can make comparisons.

[0071] The first voltage conversion circuit 131 is connected to the first PTAT current generation circuit and is configured to convert the first linear temperature-compensated current I... C1 Convert to the first voltage V1. See example for further details. Figure 6 The first voltage conversion circuit 131 is connected to the output terminal of the first current replication unit, and is connected to the first PTAT current generation circuit 110 through the first current replication unit, so as to convert the replicated first linear temperature-compensated current I... C1 This is converted to a first voltage V1. For example, the first voltage conversion circuit 131 includes a resistor R. Z1 resistance R Z1 It is connected between the output of the first current replication unit and ground. The first voltage conversion circuit 131 converts current into voltage output based on Ohm's law. And, a resistor R is used. Z1 Shunt, resistor R Z1 A linear temperature-compensated current I is generated at both ends. C1 The voltage drop is proportional to the voltage drop, that is, the first voltage V1 output by the first voltage conversion circuit 131 and the first linear temperature-compensated current I.C1 Related.

[0072] Furthermore, the second voltage conversion circuit 132 is configured to convert the second linear temperature-compensated current I... C2 This is converted to the second voltage V2. See the example for further details. Figure 6 The second voltage conversion circuit 132 is connected to the output terminal of the second current replication unit, and is connected to the second PTAT current generation circuit 120 through the second current replication unit, so as to convert the replicated second linear temperature-compensated current I... C2 This is converted to a second voltage V2. For example, the second voltage conversion circuit 132 includes a resistor R. Z2 The second voltage conversion circuit 132 converts current into voltage output based on Ohm's law. It also uses a resistor R. Z2 Shunt, resistor R Z2 A second linear temperature-compensated current I is generated at both ends. C2 The voltage drop is proportional to the voltage drop, that is, the second voltage V2 output by the second voltage conversion circuit 132 and the second linear temperature-compensated current I. C2 Related.

[0073] The two input terminals of comparator 133 in comparison module 130 are respectively connected to the first voltage conversion circuit 131 and the second voltage conversion circuit 132. For example, the output terminal of the first voltage conversion circuit 131 is coupled to one input terminal of comparator 133, and the output terminal of the second voltage conversion circuit 132 is coupled to the other input terminal of comparator 133. Comparator 133 in comparison module 130 compares the first voltage V1 and the second voltage V2 and outputs the comparison result. The comparison result output by comparator 133 can characterize the first linear temperature-compensated current I. C1 Second linear temperature-compensated current I C2 The size relationship.

[0074] In some embodiments, both the first voltage conversion circuit 131 and the second voltage conversion circuit 132 have zero temperature coefficients, such as the resistor R mentioned above. Z1 and resistance R Z2 It can be a zero-temperature coefficient resistor; and for the same input current, the magnitude of the first voltage V1 output by the first voltage conversion circuit 131 is equal to the magnitude of the second voltage V2 output by the second voltage conversion circuit 132, for example, the resistor R mentioned above. Z1 and resistance R Z2 The resistance values ​​are equal. Thus, the first voltage V1 output by the first voltage conversion circuit 131 is related to the temperature characteristics of the first resistor R1 in the first PTAT current generating circuit 110, and is not affected by the temperature characteristics of the resistor R1 in the first voltage conversion circuit 131. z1 The resistance value affects the first linear temperature-compensated current I. C1 The magnitude and stability of the first voltage V1 characterize the first linear temperature-compensated current I.C1 The temperature characteristics of the second voltage V2 output by the second voltage conversion circuit 132 and the second resistor R2 in the second PTAT current generation circuit 120 are related and will not be affected by the temperature characteristics of the resistor R in the second voltage conversion circuit 132. z2 The resistance value affects the second linear temperature-compensated current I. C2 The magnitude and stability of the second voltage V2 characterize the second linear temperature-compensated current I. C2 Temperature characteristics. This ensures that the comparator module can operate under the first linear temperature-compensated current I. C1 Second linear temperature-compensated current I C2 When they are equal, the comparison result of the comparison module 130 is flipped.

[0075] based on Figure 6 The circuit structure of the temperature compensation circuit 100 shown has a switching module 140 configured to selectively connect either the output terminal of the first PTAT current generating circuit 110 to the output terminal of the switching module 140, or the output terminal of the second PTAT current generating circuit 120 to the output terminal of the switching module 140. The first linear temperature compensation current I... C1 Second linear temperature-compensated current I C2 The weighting coefficients are 0% and 100%, or 0% and 100%.

[0076] For example, such as Figure 6 As shown, the switching module 140 includes a first switch S1 and a second switch S2. The first terminal of the first switch S1 is connected to the output terminal of the switching module 140, and the second terminal of the first switch S1 is connected to the output terminal of the first PTAT current generating circuit 110. The control terminal of the first switch S1 receives a first control signal Ctrl1 and is configured to selectively conduct the first PTAT current generating circuit 110 to the output terminal of the switching module 140 based on the first control signal Ctrl1 output by the comparison module. The current at the output terminal of the switching module 140 is equal to the first linear temperature-compensated current I. C1 .

[0077] The first terminal of the second switch S2 is connected to the output terminal of the switching module 140, and the second terminal of the second switch S2 is connected to the output terminal of the second PTAT current generating circuit 120. The control terminal of the second switch S2 receives the second control signal Ctrl2 and is configured to selectively conduct the output terminal of the second PTAT current generating circuit 120 connected to the output terminal of the switching module 140 based on the second control signal Ctrl2 output by the comparison module. The current at the output terminal of the switching module 140 is equal to the second linear temperature-compensated current I. C2 .

[0078] The following example illustrates how the resistance values ​​of the first resistor R1 and the second resistor R2 are equal at a set temperature point Ta. Figure 7Aand Figure 7B This example illustrates how the temperature compensation circuit 100 outputs different temperature compensation currents at different temperature ranges.

[0079] When the temperature is below the set temperature point Ta, the resistance of the first resistor R1 is less than the resistance of the second resistor R2, and the first linear temperature-compensated current I... C1 Less than the second linear temperature compensation current I C2 The first voltage V1 is less than the second voltage V2. For example... Figure 7A As shown, comparator 133 outputs a first control signal Ctrl1 and a second control signal Ctrl2, controlling the first switch S1 to turn on and the second switch S2 to turn off. The output terminal of the first PTAT current generating circuit 110 is connected to the output terminal of the temperature compensation circuit 100, and the first linear temperature compensation current I is generated. C1 The actual temperature compensation current I of the temperature compensation circuit 100 C Output.

[0080] Within a temperature range greater than or equal to the set temperature point, the resistance of the first resistor R1 is greater than or equal to the resistance of the second resistor R2, and the first linear temperature-compensated current I... C1 Greater than or equal to the second linear temperature-compensated current I C2 The first voltage V1 is greater than or equal to the second voltage V2. For example... Figure 7B As shown, comparator 133 outputs a first control signal Ctrl1 and a second control signal Ctrl2, controlling the first switch S1 to open and the second switch S2 to open. The output terminal of the second PTAT current generating circuit 120 is connected to the output terminal of the temperature compensation circuit 100, and the second linear temperature compensation current I is generated. C2 The actual temperature compensation current I of the temperature compensation circuit 100 C Output.

[0081] In this way, the compensation current output of different linear current generating modules can be switched through module 140 according to different temperature change ranges. Among them, the temperature coefficients of the first resistor R1 and the second resistor R2 in different linear current generating modules are different, which can provide different degrees of current compensation for non-linear current changes and improve the accuracy of temperature-compensated current.

[0082] In other embodiments, when the resistance values ​​of the first resistor R1 and the second resistor R2 are in other relationships, when the temperature reaches the set temperature point Ta, the voltage difference between the first voltage V1 and the second voltage V2 can also trigger changes in the first control signal Ctrl1 and the second control signal Ctrl2 output by the comparator 133, thereby controlling the switching module 140 to connect to the output terminal of the third transistor, so as to convert the first linear temperature-compensated current I... C1As an output, or control switching module 140 is connected to the output terminal of the sixth transistor T6 to convert the second linear temperature-compensated current I... C2 As output.

[0083] In the example above, the switching module 140 employs multiple independent switches to select the first linear temperature-compensated current I in response to different control signals. C1 Or the second linear temperature-compensated current I C2 The data is transmitted to the output of the switching module 140. The switching module 140 may also be a single-pole double-throw switch, a multiplexer, or other electronic components or circuits used to selectively connect at least one of the multiple linear current generating modules to the output of the switching module 140. This application does not impose specific limitations on this, and it can be configured according to actual needs.

[0084] In some examples, the first transistor T1 through the eighth transistor T8 can all be metal-oxide-semiconductor field-effect transistors (MOSFETs), bipolar transistors (BJTs), or transistors of other structures.

[0085] In the examples provided in this application, the current mirrors can all be single-transistor MOS current mirrors for illustration. For example, the first current mirror and the second current mirror adopt a simple single-transistor MOS current mirror structure. However, under the same design concept, all current mirrors can also include other improved structures, such as cascode current mirrors, Wilson current mirrors, etc.

[0086] Figure 8 The temperature compensation circuit 100 shown is... Figure 6 The main difference between the temperature compensation circuit 100 shown lies in the circuit structure of the switching module 140. The following example is based on... Figure 8 The circuit of the switching module 140 shown is illustrated by way of example. Figure 8 The temperature compensation circuit 100 shown outputs a temperature compensation current I. C The process and principles.

[0087] exist Figure 8 In the middle, the temperature compensation current I output by the switching module 140 C It is part of the first linear temperature-compensated current I C1 and part of the second linear temperature-compensated current I C2 The weighted sum, switching module 140 changes the first linear temperature compensation current I C1 Or the second linear temperature-compensated current I C2The weighting ratio. For example, the switching module 140 includes a first voltage divider element 141A and a second voltage divider element 141B. The first voltage divider element 141A is connected between the output terminal of the first PTAT current generating circuit 110 and the output terminal of the switching module 140, and the second voltage divider element 141B is connected between the output terminal of the second PTAT current generating circuit 120 and the output terminal of the switching module 140. The first voltage divider element 141A and / or the second voltage divider element 141B are adjustable resistors. The resistance value of the adjustable resistor is adjusted based on the comparison result of the comparator 133, thereby adjusting the resistance ratio of the first voltage divider element 141A and the second voltage divider element 141B. This adjustable resistance ratio allows for different voltage division ratios in the transmission paths of the first linear temperature-compensated current IC1 and the second linear temperature-compensated current IC2, resulting in two different weighted combinations of the first linear temperature-compensated current IC1 and the second linear temperature-compensated current IC2. In other words, in Formulas 1 and 2, a1, a2, b1, and b2 are all less than 1 and greater than 0, and a1:a2 ≠ b1:b2.

[0088] For example, the adjustable resistor includes at least one switching unit and multiple regulating resistors connected in parallel, with the switching unit connected in series with a corresponding regulating resistor. The switching unit turns on or off based on a comparison result. Figure 8 As shown, the first voltage divider element 141A is an adjustable resistor, including multiple adjustable resistors connected in parallel (the third resistor R3 and the fifth resistor R5); the second voltage divider element 141B is an adjustable resistor, including multiple adjustable resistors connected in parallel (the fourth resistor R4 and the sixth resistor R6). The temperature coefficients of the third resistor R3, the fourth resistor R4, the fifth resistor R5, and the sixth resistor R6 are all zero temperature coefficients to avoid affecting the temperature compensation current Ic.

[0089] For example, the switching unit includes a third switch S3, a fourth switch S4, a fifth switch S5, and a sixth switch S6. A third resistor R3 and a third switch S3 are connected in series between the output of the switching module 140 and the output of the first PTAT current generating circuit 110; a fourth resistor R4 and a fourth switch S4 are connected in series between the output of the switching module 140 and the output of the second PTAT current generating circuit 120. A fifth resistor R5 and a fifth switch S5 are connected in series between the output of the switching module 140 and the output of the first PTAT current generating circuit 110; and a sixth resistor R6 and a sixth switch S6 are connected in series between the output of the switching module 140 and the output of the second PTAT current generating circuit 120.

[0090] For example, the control terminals of the third switch S3 and the fourth switch S4 receive the first control signal Ctrl1, and the control terminals of the fifth switch S5 and the sixth switch S6 receive the second control signal Ctrl2. When the first control signal Ctrl1 is valid, the third switch S3 and the fourth switch S4 are turned on, and the fifth switch S5 and the sixth switch S6 are turned off, so that the third resistor R3 and the fourth resistor R4 are respectively connected to the transmission paths of the first linear temperature compensation current IC1 and the second linear temperature compensation current IC2; when the second control signal Ctrl2 is valid, the fifth switch S5 and the sixth switch S6 are turned on, and the third switch S3 and the fourth switch S4 are turned off, so that the fifth resistor R5 and the sixth resistor R6 are respectively connected to the transmission paths of the first linear temperature compensation current IC1 and the second linear temperature compensation current IC2.

[0091] The resistance ratio of the third resistor R3 to the fourth resistor R4 (R3:R4) differs from the resistance ratio of the fifth resistor R5 to the sixth resistor R6 (R5:R6). This causes the voltage division coefficients of the first and second voltage divider elements to change under different switching states, resulting in different voltage division ratios in the transmission paths of the first linear temperature compensation current IC1 and the second linear temperature compensation current IC2. This enables two different weighted combinations of the first and second linear temperature compensation current IC1 and IC2. When the comparator 133 flips at the set temperature point Ta, the control signals Ctrl1 and Ctrl2 switch accordingly, changing the current weights of the first PTAT current generation circuit 110 and the second PTAT current generation circuit 120 on the output temperature compensation current IC, thereby adjusting the slope of the overall temperature compensation characteristic.

[0092] Specifically, based on the first voltage conversion circuit 131 in the comparison module 130, the (copied) first linear temperature-compensated current I... C1 Converted to the first voltage V1; the second voltage conversion circuit 132 in the comparison module 130 converts the (copied) second linear temperature-compensated current I... C2 It is converted into the second voltage V2.

[0093] The following example illustrates how the resistance values ​​of the first resistor R1 and the second resistor R2 are equal at a set temperature point Ta. Figure 9A and Figure 9B This example illustrates how the temperature compensation circuit 100 outputs different temperature compensation currents at different temperature ranges.

[0094] When the temperature is below the set temperature point Ta, the resistance of the first resistor R1 is less than the resistance of the second resistor R2, and the first linear temperature-compensated current I... C1 Less than the second linear temperature compensation current I C2 The first voltage V1 is less than the second voltage V2. For example... Figure 9AAs shown, comparator 133 outputs a first control signal Ctrl1 and a second control signal Ctrl2, controlling the third switch S3 and the fourth switch S4 to be turned on, and the fifth switch S5 and the sixth switch S6 to be turned off. The first PTAT current generating circuit 110 is connected to the output terminal of the temperature compensation circuit 100 through the third resistor R3; the second PTAT current generating circuit 120 is connected to the output terminal of the temperature compensation circuit 100 through the fourth resistor R4; assuming that the ratio of the resistance of the third resistor R3 to the resistance of the fourth resistor R4 is 1 / 2; the first linear temperature compensation current I... C1 The weighting ratio is 1 / 3, and the second linear temperature-compensated current I C2 The weighting ratio is 2 / 3, and 1 / 3 of the first linear temperature-compensated current I is used. C1 and 2 / 3 of the second linear temperature-compensated current I C2 The weighted sum is output to the output terminal of the temperature compensation circuit 100 (i.e., the output terminal of the switching module 140).

[0095] When the temperature reaches or exceeds the temperature point Ta, the resistance of the first resistor R1 is greater than or equal to the resistance of the second resistor R2, and the first linear temperature-compensated current I... C1 Greater than or equal to the second linear temperature-compensated current I C2 The first voltage V1 is greater than the second voltage V2. For example... Figure 9B As shown, the third switch S3 and the fourth switch S4 are open, while the fifth switch S5 and the sixth switch S6 are open. The first PTAT current generating circuit 110 is connected to the output terminal of the temperature compensation circuit 100 through the fifth resistor R5; the second PTAT current generating circuit 120 is connected to the output terminal of the temperature compensation circuit 100 through the sixth resistor R6; assuming that the ratio of the resistance of the fifth resistor R5 to the resistance of the sixth resistor R6 is 2 / 1; the first linear temperature compensation current I... C1 The weighting ratio is 2 / 3, and the second linear temperature-compensated current I C2 The weighting ratio is 1 / 3, and 2 / 3 of the first linear temperature-compensated current I is used. C1 and 1 / 3 of the second linear temperature-compensated current I C2 The weighted sum is output to the output terminal of the temperature compensation circuit 100.

[0096] exist Figure 8 , Figure 9A and Figure 9B In the illustrated embodiment, the relationship between the temperature compensation current Ic and the temperature is as follows: Figure 10 As shown. Within a temperature range below the set temperature point Ta, the first linear temperature-compensated current I transmitted by the first PTAT current generating circuit 110 is... C1 The weighting value is 1 / 3, and the second linear temperature-compensated current I transmitted by the second PTAT current generation circuit 120 is... C2The weighting value is 2 / 3; within a temperature range greater than or equal to the set temperature point Ta, the first linear temperature-compensated current I transmitted by the first PTAT current generating circuit 110 is... C1 The weighting value is 2 / 3, and the second linear temperature-compensated current I transmitted by the second PTAT current generation circuit 120 is... C2 The weighting value is 1 / 3, which realizes the nonlinear temperature compensation current.

[0097] In other embodiments, when the resistance values ​​of the first resistor R1 and the second resistor R2 are in other relationships, when the temperature reaches the set temperature point Ta, the voltage magnitude between the first voltage V1 and the second voltage V2 can also trigger the first control signal Ctrl1 and the second control signal Ctrl2 output by the comparator 133 to change, so as to control the switching module 140 to change the weighting ratio.

[0098] In the example above, the adjustable resistor in the switching module 140 achieves the voltage division effect by combining a switch and a resistor. The adjustable resistor can also be implemented by a digital programmable voltage divider, a MOS gate voltage divider structure, or other active / passive circuits with voltage division function.

[0099] In other embodiments, the first voltage divider element 141A can be a fixed resistor, and the second voltage divider element 141B can be an adjustable resistor. For example, the first voltage divider element 141A includes a third resistor R3, meaning the transmission path of the first linear temperature-compensated current IC1 is connected to the output terminal through the third resistor R3, eliminating the need for a separate fifth resistor R5. In this case, the third switch S3 and the fifth switch S5 can also be omitted. By controlling the fourth switch S4 and the sixth switch S6 to turn on or off through control signals Ctrl1 and Ctrl2 respectively, the second linear temperature-compensated current IC2 can still be selectively introduced to the output terminal via the fourth resistor R4 or the sixth resistor R6, thereby adjusting the resistance ratio of the first voltage divider element and the second voltage divider element, changing the current distribution ratio between the first linear temperature-compensated current IC1 and the second linear temperature-compensated current IC2, and realizing two different weighted output modes. This structure simplifies circuit complexity, reduces power consumption and chip area while ensuring the weighted switching function, making it suitable for applications with high integration requirements.

[0100] In the above example, the switching unit uses multiple independent switches, with each regulating resistor corresponding to an independent switch. In other embodiments, the third resistor R3 and the fourth resistor R4 are connected in series between the output terminal of the first PTAT current generating circuit 110 (e.g., the output terminal of the third transistor T3) and the output terminal of the second PTAT current generating circuit 120 (e.g., the output terminal of the sixth transistor T6). The intermediate node between the third resistor R3 and the fourth resistor R4 is connected to the output terminal of the switching module 140 through the third switch. The fifth resistor R5 and the sixth resistor R6 are connected in series between the output terminal of the first PTAT current generating circuit 110 (e.g., the output terminal of the third transistor T3) and the output terminal of the second PTAT current generating circuit 120 (e.g., the output terminal of the sixth transistor T6). The intermediate node between the fifth resistor R5 and the sixth resistor R6 is connected to the output terminal of the switching module 140 through the fifth switch, thereby adjusting the resistance ratio of the first voltage divider element and the second voltage divider element.

[0101] In the above example, multiple adjustable resistors are connected in parallel. In other embodiments, the multiple adjustable resistors can also be connected in series, and the switching unit is connected in parallel with the corresponding adjustable resistor. Figure 9C As shown, the first voltage divider element 141A includes multiple adjustable resistors connected in series (third resistor R3 and fifth resistor R5); the second voltage divider element 141B includes multiple adjustable resistors connected in series (fourth resistor R4 and sixth resistor R6). The switching unit includes third switches S3 to sixth switches S6. Third switches S3 to sixth switches S6 are connected in parallel with third resistors R3 to sixth resistors R6 respectively, and the corresponding resistors are short-circuited when the switches are on. The control terminals of third switches S3 and fourth switches S4 receive a first control signal Ctrl1, and the control terminals of fifth switches S5 and sixth switches S6 receive a second control signal Ctrl2. When the first control signal Ctrl1 is valid, the third switch S3 and the fourth switch S4 are turned on, and the fifth switch S5 and the sixth switch S6 are turned off, so that the fifth resistor R5 and the sixth resistor R6 are respectively connected to the transmission paths of the first linear temperature compensation current IC1 and the second linear temperature compensation current IC2; when the second control signal Ctrl2 is valid, the fifth switch S5 and the sixth switch S6 are turned on, and the third switch S3 and the fourth switch S4 are turned off, so that the third resistor R3 and the fourth resistor R4 are respectively connected to the transmission paths of the first linear temperature compensation current IC1 and the second linear temperature compensation current IC2, thereby adjusting the resistance ratio of the first voltage divider element and the second voltage divider element to achieve two different current weighting ratios.

[0102] Figure 11 A schematic diagram of another temperature compensation circuit 100 is shown. Compared to Figure 6 The temperature compensation circuit shown is... Figure 11In the temperature compensation circuit 100, voltage clamping is achieved through a first auxiliary transistor T13 and a second auxiliary transistor T14. The output terminal of the first transistor T1 is connected to the first terminal of the first auxiliary transistor T13, the second terminal of the first auxiliary transistor T13 is connected to the first terminal of the first unidirectional conduction unit U1, and the first terminal of the first auxiliary transistor T13 is connected to its control terminal. The first terminal of the second auxiliary transistor T14 is connected to the control terminal of the second transistor T2, the second terminal of the second auxiliary transistor T14 is connected to one end of the first resistor R1, and the control terminal of the second auxiliary transistor T14 is connected to the control terminal of the first transistor T13. The output terminal of the second transistor T2 is connected to its control terminal. The negative feedback between the second transistor T2 and the first auxiliary transistor T13 ensures that the voltage at the second terminal of the first auxiliary transistor T13 is equal to the voltage at the second terminal of the second auxiliary transistor T14.

[0103] Continue reading Figure 11 In the second PTAT current generating circuit 120, voltage clamping is achieved through the third auxiliary transistor T15 and the fourth auxiliary transistor T16. The output terminal of the fourth transistor T4 is connected to the first terminal of the third auxiliary transistor T15, the second terminal of the third auxiliary transistor T15 is connected to the first terminal of the third unidirectional conduction unit U3, and the first terminal of the third auxiliary transistor T15 is connected to its control terminal. The first terminal of the fourth auxiliary transistor T16 is connected to the control terminal of the fifth transistor T5, the second terminal of the fourth auxiliary transistor T16 is connected to one end of the second resistor R2, and the control terminal of the fourth auxiliary transistor T16 is connected to the control terminal of the third auxiliary transistor T15. The output terminal of the fifth transistor T5 is connected to its control terminal. The negative feedback between the fifth transistor T5 and the third auxiliary transistor T15 ensures that the voltage at the second terminal of the third auxiliary transistor T15 is equal to the voltage at the second terminal of the fourth auxiliary transistor T16.

[0104] Figure 12 A schematic diagram of yet another temperature compensation circuit 100 is shown. Figure 12 The temperature compensation circuit 100 shown is... Figure 6 The main difference in the temperature compensation circuit 100 shown lies in the type and connection of the transistors within the unidirectional conduction unit. For example, Figure 6 The ninth transistor T9, tenth transistor T10, eleventh transistor T11 and twelfth transistor T12 of the first unidirectional conduction unit U1 in the temperature compensation circuit 100 shown are PNP type transistors.

[0105] like Figure 12As shown, the ninth transistor T9 to the twelfth transistor T12 of the first unidirectional conduction unit U1 in the temperature compensation circuit 100 are NPN type transistors. The control terminal of the NPN type transistor is connected to the first terminal of the ninth transistor T9.

[0106] Figure 13 A schematic diagram of another temperature compensation circuit 100 is shown. Compared to Figure 6 The temperature compensation circuit shown is... Figure 13 The temperature compensation circuit 100 also includes a third amplifier 134 and a fourth amplifier 135. The resistor R of the first voltage conversion circuit... Z1 A resistor is connected in series between the output of the second transistor T2 and the first resistor R1 to convert the current flowing through the second transistor T2 into voltage; the two input terminals of the third amplifier 134 are respectively connected to resistor R. Z1 The two ends are used to connect the resistor R Z1 The voltage at both ends is converted into a single-ended voltage; the output of the third amplifier 134 outputs a first voltage V1, which is used to characterize the magnitude of the current flowing through the second transistor T2.

[0107] The resistor R in the second voltage conversion circuit Z2 A resistor R2 is connected in series between the output of the fifth transistor T5 and the second resistor to convert the current flowing through the fifth transistor T5 into voltage; the two inputs of the fourth amplifier 135 are respectively connected to resistor R Z2 The two ends are used to connect the resistor R Z2 The voltage at both ends is converted into a single-ended voltage; the output of the fourth amplifier 135 outputs a second voltage V2, which is used to characterize the magnitude of the current flowing through the fifth transistor T5.

[0108] In the first PTAT current generating circuit 110, the gates of the first transistor T1, the second transistor T2, and the third transistor T3 are connected, and their sources are all connected to the power supply voltage (such as VDD). Therefore, the current flowing through the second transistor T2 and the current output by the third transistor T3 are related. C1 They are in a fixed ratio; similarly, the fourth transistor T4, the fifth transistor T5, and the sixth transistor T6 have the same gate voltage and source potential, and the current flowing through the fifth transistor T5 is proportional to the I output of the sixth transistor T6. C2 It is in a fixed ratio. Combined with resistance R Z1 With resistance R Z2 Having the same resistance and zero temperature coefficient, the voltage signals generated by both can accurately reflect the first linear temperature-compensated current I. C1 Second linear temperature-compensated current I C2 The magnitude of the current.

[0109] Therefore, comparator 133 can compare the currents flowing through the second transistor T2 and the fifth transistor T5 to compare the first linear temperature-compensated current I. C1 Second linear temperature-compensated current I C2 Size.

[0110] In some examples, comparator 133 may include a static comparator or a dynamic comparator. The examples provided in this application are not limited in this regard, and the appropriate comparator can be selected according to actual needs. Comparator 133 can be a differential structure, thereby outputting two opposite control signals Ctrl1 and Ctrl2. For example, as... Figure 14 As shown in (a), the static comparator includes transistors M9-M15. The control terminal of transistor M9 is connected to the bias voltage VB1. The control terminals of transistors M10 and M11 are connected to the first node N1 and the second node N2, respectively. The voltages of the first node N1 and the second node N2 serve as the control signals Vin1 and Vin2 for transistors M10 and M11, respectively. The drains of transistors M13 and M14 output control signals Ctrl2 and Ctrl1, respectively. For example, as... Figure 14 As shown in (b), the dynamic comparator includes transistors M16-M24, wherein transistors M18 and M20, together with transistors M19 and M21, form a set of inverters. The control terminals of transistors M22-M24 receive the clock CLK. The control terminals of transistors M16 and M17 are connected to the first node N1 and the second node N2, respectively. The voltages of the first node N1 and the second node N2 serve as the control signals INN and INP of transistors M16 and M17. The series connection point of transistors M18 and M20 transmits signal Ctrl1, and the series connection point of transistors M19 and M21 transmits signal Ctrl2.

[0111] The above description is merely an embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A temperature compensation circuit, characterized in that, include: The first PTAT current generating circuit is configured to output a first linear temperature-compensated current having a first temperature coefficient. The first PTAT current generating circuit includes a first resistor, which is used to convert a temperature-proportional voltage into the first linear temperature-compensated current. The second PTAT current generating circuit is configured to output a second linear temperature-compensated current having a second temperature coefficient; the second PTAT current generating circuit includes a second resistor, which is used to convert a temperature-proportional voltage into the second linear temperature-compensated current; wherein the first temperature coefficient is different from the second temperature coefficient; the resistance values ​​of the first resistor and the second resistor are used to control the current values ​​of the first linear temperature-compensated current and the second linear temperature-compensated current, wherein, at a set temperature, the current values ​​of the first linear temperature-compensated current and the second linear temperature-compensated current are equal; The comparison module, connected to the first PTAT current generation circuit and the second PTAT current generation circuit, is configured to compare the magnitudes of the first linear temperature-compensated current and the second linear temperature-compensated current, and output the comparison result. The switching module is connected to the comparison module and configured to: based on the comparison result, change the weighting ratio of the first linear temperature compensation current and the second linear temperature compensation current, and then output a temperature compensation current.

2. The temperature compensation circuit according to claim 1, characterized in that, The switching module is configured to selectively connect the output terminal of the first PTAT current generating circuit to the output terminal of the switching module, or connect the output terminal of the second PTAT current generating circuit to the output terminal of the switching module.

3. The temperature compensation circuit according to claim 2, characterized in that, The switching module includes a first switch and a second switch; The first switch is configured to selectively connect the output terminal of the first PTAT current generating circuit to the output terminal of the switching module based on the first control signal output by the comparison module. The second switch is configured to selectively connect the output terminal of the second PTAT current generating circuit to the output terminal of the switching module based on the second control signal output by the comparison module.

4. The temperature compensation circuit according to claim 1, characterized in that, The switching module includes a first voltage divider element and a second voltage divider element. The first voltage divider element is connected between the output terminal of the first PTAT current generating circuit and the output terminal of the switching module, and the second voltage divider element is connected between the output terminal of the second PTAT current generating circuit and the output terminal of the switching module. The first voltage divider element and / or the second voltage divider element are adjustable resistors, and the resistance value of the adjustable resistors is adjusted based on the comparison result to adjust the resistance ratio between the first voltage divider element and the second voltage divider element.

5. The temperature compensation circuit according to claim 4, characterized in that, The adjustable resistor includes at least one switching unit and multiple adjusting resistors, wherein the switching unit is turned on or off based on the comparison result; Multiple regulating resistors are connected in parallel, and the switching unit is connected in series with the corresponding regulating resistor; or, Multiple regulating resistors are connected in series, and the switching unit is connected in parallel with the corresponding regulating resistor.

6. The temperature compensation circuit according to claim 5, characterized in that, The temperature coefficient of the first voltage divider element and / or the temperature coefficient of the second voltage divider element are zero.

7. The temperature compensation circuit according to claim 1, characterized in that, The temperature coefficient of the first resistor is zero, and the temperature coefficient of the second resistor is either positive or negative. Alternatively, the temperature coefficients of the first resistor and the second resistor may both be positive or negative temperature coefficients.

8. The temperature compensation circuit according to claim 1, characterized in that, The first PTAT current generating circuit includes: The first current mirror includes a first transistor, a second transistor, and a third transistor, wherein the control terminals of the first transistor, the second transistor, and the third transistor are all coupled together. The first unidirectional conduction unit and the second unidirectional conduction unit are respectively connected to the output terminal of the first transistor and the output terminal of the second transistor; The first resistor is connected between the second transistor and the second unidirectional conduction unit; The output terminal of the third transistor outputs the first linear temperature-compensated current. And / or, The second PTAT current generating circuit includes: The second current mirror includes a fourth transistor, a fifth transistor, and a sixth transistor, wherein the control terminals of the fourth transistor, the fifth transistor, and the sixth transistor are all coupled together. The third unidirectional conduction unit and the fourth unidirectional conduction unit are respectively connected to the output terminal of the fourth transistor and the output terminal of the fifth transistor; The second resistor is connected between the fourth transistor and the fourth unidirectional conduction unit; The output terminal of the sixth transistor outputs the second linear temperature-compensated current.

9. The temperature compensation circuit according to claim 8, characterized in that, The first PTAT current generating circuit further includes: A first amplifier, wherein the output terminal of the first amplifier is connected to the control terminal of the first transistor, the first input terminal of the first amplifier is connected to the output terminal of the first transistor, and the second input terminal of the first amplifier is connected to the output terminal of the second transistor; or A first auxiliary transistor and a second auxiliary transistor; the first terminal of the first auxiliary transistor is connected to the output terminal of the first transistor, the second terminal of the first auxiliary transistor is connected to the first terminal of the first unidirectional conduction unit, and the first terminal of the first auxiliary transistor is connected to the control terminal of the first auxiliary transistor; the first terminal of the second auxiliary transistor is connected to the control terminal of the second transistor, the second terminal of the second auxiliary transistor is connected to one end of the first resistor, and the control terminal of the second auxiliary transistor is connected to the control terminal of the first auxiliary transistor.

10. The temperature compensation circuit according to claim 9, characterized in that, The second PTAT current generating circuit also includes: A second amplifier, the output of which is connected to the control terminal of the first transistor, the first input of which is connected to the output of the fourth transistor, and the second input of which is connected to the output of the fifth transistor; or... A third auxiliary transistor and a fourth auxiliary transistor; the first terminal of the third auxiliary transistor is connected to the output terminal of the fourth transistor, the second terminal of the third auxiliary transistor is connected to the first terminal of the first unidirectional conduction unit, and the first terminal of the third auxiliary transistor is connected to the control terminal of the first auxiliary transistor; the first terminal of the fourth auxiliary transistor is connected to the control terminal of the fifth transistor, the second terminal of the fourth auxiliary transistor is connected to one end of the first resistor, and the control terminal of the fourth auxiliary transistor is connected to the control terminal of the third auxiliary transistor.

11. The temperature compensation circuit according to claim 8, characterized in that, The first unidirectional conduction unit and the third unidirectional conduction unit have the same size; The second unidirectional conducting unit, the fourth unidirectional conducting unit, the first resistor, and the second resistor satisfy the following relationship: The size of the second unidirectional conduction unit is larger than that of the fourth unidirectional conduction unit. When the temperature point is set, the resistance value of the first resistor is greater than that of the second resistor. The size of the second unidirectional conduction unit is equal to the size of the fourth unidirectional conduction unit, and at the set temperature point, the resistance value of the first resistor is equal to the resistance value of the second resistor. The size of the second unidirectional conduction unit is smaller than that of the fourth unidirectional conduction unit, and at the set temperature point, the resistance value of the first resistor is smaller than that of the second resistor.

12. The temperature compensation circuit according to claim 11, characterized in that, The size of the first transistor is equal to the size of the fourth transistor, the size of the second transistor is equal to the size of the fifth transistor, and the size of the third transistor is equal to the size of the sixth transistor.

13. The temperature compensation circuit according to claim 9, characterized in that, The comparison module includes: A first voltage conversion circuit is connected in series between the output terminal of the second transistor and the second input terminal of the first amplifier. The third amplifier is connected across the first voltage conversion circuit and outputs the first voltage; The second voltage conversion circuit is connected in series between the output terminal of the fifth transistor and the second input terminal of the second amplifier. The fourth amplifier is connected across the two ends of the second voltage conversion circuit and outputs the second voltage; The comparator, with its two inputs connected to the outputs of the third amplifier and the fourth amplifier respectively, is configured to compare the first voltage and the second voltage and output the comparison result.

14. The temperature compensation circuit according to claim 1, characterized in that, The temperature compensation circuit also includes: The first current replication unit is connected to the first PTAT current generation circuit and is configured to replicate the first linear temperature-compensated current. The second current replication unit, connected to the second PTAT current generation circuit, is configured to replicate the second linear temperature-compensated current. The comparison module is connected to the output terminals of the first current replication unit and the second current replication unit, respectively, and is configured to compare the replicated first linear temperature-compensated current and the replicated second linear temperature-compensated current.

15. The temperature compensation circuit according to claim 14, characterized in that, The first current replication unit replicates the first linear temperature-compensated current at a 1:1 ratio, and the second current replication unit replicates the second linear temperature-compensated current at a 1:1 ratio.

16. The temperature compensation circuit according to claim 14, characterized in that, The comparison module includes: A first voltage conversion circuit, connected to the output of the first current replication unit, is configured to convert the replicated first linear temperature-compensated current into a first voltage. The second voltage conversion circuit, connected to the output of the second current replication unit, is configured to convert the replicated second linear temperature-compensated current into a second voltage. A comparator, whose two input terminals are respectively connected to the output terminals of the first voltage conversion circuit and the second voltage conversion circuit, is configured to compare the first voltage and the second voltage and output the comparison result.

17. The temperature compensation circuit according to claim 13 or 16, characterized in that, Both the first voltage conversion circuit and the second voltage conversion circuit have a temperature coefficient of zero; and for the same input current, the magnitude of the first voltage output by the first voltage conversion circuit is equal to the magnitude of the second voltage output by the second voltage conversion circuit.

Images