Converter circuit, power stage circuit and temperature balancing method

Abstract

The invention provides a converter circuit, a power stage circuit and a temperature balancing method. The converter circuit includes a plurality of power stage circuits and a control circuit. The power stage circuit includes a power circuit, a temperature sensing circuit, a current sensing circuit, and a current feedback control circuit. The temperature sensing circuit senses the temperature of the power stage circuit to output a temperature sensing value. The current sensing circuit senses an output current of the power circuit to output a current sensing value. The current feedback control circuit compares the temperature sensing value with the highest temperature value of the plurality of power level circuits, and outputs one of the current sensing value and the adjusted current sensing value to the control circuit according to the comparison result of the temperature sensing value and the highest temperature value. The current sensing value is selectively adjusted by the power level circuit according to the comparison result of the temperature sensing value and the highest temperature value, and the converter circuit can automatically control the plurality of power level circuits to achieve temperature balance without manual adjustment of a user.

Description

Technical Field

[0001] The present invention relates to a power stage circuit and a temperature balancing method, and more particularly to a power stage circuit and a temperature balancing method applied to a converter circuit. Background Art

[0002] In the related art of multi-phase buck converter, the controller adjusts the duty cycle of the pulse width modulation signal according to the current sensing value reported by each phase smart power stage (SPS) circuit to achieve current balance of each phase smart power stage circuit. In addition, the user can further manually adjust the current sensing value received by the controller through the controller to achieve temperature balance of each phase smart power stage circuit. However, since the user needs to manually adjust, this approach is extremely inconvenient for the user. Summary of the invention

[0003] One aspect of the present invention is a converter circuit. The converter circuit includes a plurality of power stage circuits and a control circuit. The plurality of power stage circuits are used to output a plurality of output currents according to a plurality of control signals, and to selectively adjust a plurality of current sensing values ​​corresponding to the plurality of output currents according to a comparison result between a plurality of temperature sensing values ​​of the plurality of power stage circuits and a maximum temperature value of the plurality of power stage circuits. The control circuit is electrically coupled to the plurality of power stage circuits, and is used to output the plurality of control signals to the plurality of power stage circuits, and is used to receive the plurality of current sensing values ​​from the plurality of power stage circuits, and is used to adjust the plurality of control signals according to the plurality of current sensing values, so that the magnitudes of the plurality of output currents change.

[0004] In some embodiments, each of the plurality of power stage circuits is used to reduce and output a corresponding one of the plurality of current sensing values ​​when the corresponding one of the plurality of temperature sensing values ​​is less than the highest temperature value. Each of the plurality of power stage circuits is used to directly output the corresponding one of the plurality of current sensing values ​​when the corresponding one of the plurality of temperature sensing values ​​is equal to the highest temperature value.

[0005] In some embodiments, each of the multiple power stage circuits further includes: a power circuit for outputting a corresponding one of the multiple output currents according to a corresponding one of the multiple control signals; a temperature sensing circuit for sensing the temperature of a corresponding one of the multiple power stage circuits to output a corresponding one of the multiple temperature sensing values; a current sensing circuit for sensing the corresponding one of the multiple output currents to output a corresponding one of the multiple current sensing values; a temperature feedback end; a current feedback end; and a current feedback control circuit electrically coupled to the temperature sensing circuit, the current sensing circuit, the temperature feedback end and the current feedback end, for comparing the corresponding one of the multiple temperature sensing values ​​with the highest temperature value, and for selectively adjusting the corresponding one of the multiple current sensing values ​​according to the comparison result of the corresponding one of the multiple temperature sensing values ​​with the highest temperature value.

[0006] In some embodiments, the current feedback control circuit includes: a temperature comparison circuit, electrically coupled to the temperature sensing circuit and the temperature feedback end at a first node and a second node, respectively, and used to compare the corresponding one of the multiple temperature sensing values ​​with the highest temperature value; and a sensing value adjustment circuit, electrically coupled to the current sensing circuit, the temperature comparison circuit and the current feedback end, and used to output the corresponding one of the multiple current sensing values ​​or the corresponding one of the multiple current sensing values ​​after adjustment to the current feedback end.

[0007] In some embodiments, when the corresponding one of the plurality of temperature sensing values ​​is less than the highest temperature value, the temperature comparison circuit outputs a compensation value according to the first voltage difference generated between the first node and the second node, and the sensing value adjustment circuit reduces the corresponding one of the plurality of current sensing values ​​by the compensation value, and outputs the reduced corresponding one of the plurality of current sensing values. When the corresponding one of the plurality of temperature sensing values ​​is equal to the highest temperature value, the temperature comparison circuit outputs the compensation value having a value of zero according to the second voltage difference generated between the first node and the second node, and the sensing value adjustment circuit directly outputs the corresponding one of the plurality of current sensing values.

[0008] One aspect of the present invention is a power stage circuit. The power stage circuit includes a power circuit, a temperature sensing circuit, a current sensing circuit, a temperature feedback terminal, a current feedback terminal, and a current feedback control circuit. The power circuit is used to output an output current according to a control signal. The temperature sensing circuit is used to sense the temperature of the power stage circuit to output a temperature sensing value. The current sensing circuit is electrically coupled to the power circuit and is used to sense the output current to output a current sensing value. The temperature feedback terminal is used to receive a maximum temperature value. The current feedback control circuit is electrically coupled to the temperature sensing circuit, the current sensing circuit, the temperature feedback terminal, and the current feedback terminal to compare the temperature sensing value with the maximum temperature value, and to output one of the current sensing value and the adjusted current sensing value to the current feedback terminal according to the comparison result between the temperature sensing value and the maximum temperature value.

[0009] In some embodiments, the current feedback control circuit includes: a switch circuit, wherein a first end of the switch circuit is electrically coupled to the temperature sensing circuit at a first node, and a second end of the switch circuit is electrically coupled to the temperature feedback end at a second node; an amplifier circuit, wherein a first input end of the amplifier circuit is electrically coupled to the first node, and a second input end of the amplifier circuit is electrically coupled to the second node; and an operation circuit, electrically coupled to the current sensing circuit, an output end of the amplifier circuit, and the current feedback end.

[0010] In some embodiments, when the temperature sensing value is less than the maximum temperature value, the switch circuit is in an off state to generate a first voltage difference between the first node and the second node, the amplifier circuit outputs a compensation value according to the first voltage difference, and the operation circuit reduces the current sensing value by the compensation value, and outputs the reduced current sensing value to the current feedback terminal. When the temperature sensing value is equal to the maximum temperature value, the switch circuit is in an on state to generate a second voltage difference between the first node and the second node, the amplifier circuit outputs the compensation value of zero according to the second voltage difference, and the operation circuit directly outputs the current sensing value.

[0011] One aspect of the present invention is a temperature balancing method for a converter circuit. The temperature balancing method is applied to a converter circuit, wherein the converter circuit includes a plurality of power stage circuits and a control circuit, and the plurality of power stage circuits are used to output a plurality of output currents according to a plurality of control signals output by the control circuit. The temperature balancing method includes: comparing a plurality of temperature sensing values ​​of the plurality of power stage circuits with a maximum temperature value of the plurality of power stage circuits through the plurality of power stage circuits; selectively adjusting a plurality of current sensing values ​​corresponding to the plurality of output currents according to the comparison results of the plurality of temperature sensing values ​​with the maximum temperature value through the plurality of power stage circuits; and adjusting the plurality of control signals according to the plurality of current sensing values ​​through the control circuit, so that the magnitudes of the plurality of output currents change.

[0012] In some embodiments, the step of selectively adjusting the multiple current sensing values ​​based on the comparison results of the multiple temperature sensing values ​​and the maximum temperature value includes: when the corresponding one of the multiple temperature sensing values ​​is less than the maximum temperature value, reducing and outputting the corresponding one of the multiple current sensing values; and when the corresponding one of the multiple temperature sensing values ​​is equal to or greater than the maximum temperature value, directly outputting the corresponding one of the multiple current sensing values.

[0013] In summary, the power stage circuit selectively adjusts the current sensing value according to the comparison result between the temperature sensing value and the maximum temperature value. The converter circuit of the present invention can automatically control multiple power stage circuits to achieve temperature balance without manual adjustment by the user. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 FIG. 4 is a block diagram of a converter circuit according to some embodiments of the present invention.

[0015] Figure 2A The diagram is a schematic diagram of a current balancing operation performed by a control circuit in a converter circuit according to some embodiments of the present invention.

[0016] Figure 2B FIG. 1 is a schematic diagram of adjusting a control signal according to some embodiments of the present invention.

[0017] Figure 3 FIG. 4 is a block diagram of a power stage circuit according to some embodiments of the present invention.

[0018] Figure 4 FIG. 5 is a circuit diagram of a power stage circuit according to some embodiments of the present invention.

[0019] Figure 5 The figure is a flow chart of a temperature balancing method according to some embodiments of the present invention.

[0020] Figure 6 FIG. 4 is a schematic diagram of current sensing values ​​and adjusted current sensing values ​​according to some embodiments of the present invention.

[0021] Figure 7 FIG. 5 is a circuit diagram of a power stage circuit according to some embodiments of the present invention.

[0022] Figure 8 FIG. 5 is a circuit diagram of a power stage circuit according to some embodiments of the present invention. DETAILED DESCRIPTION

[0023] The following is a detailed description of the embodiments with the accompanying drawings, but the specific embodiments described are only used to explain the present case and are not used to limit the present case. The description of the structural operation is not used to limit the order of its execution. Any structure recombined by the elements to produce a device with equal functions is within the scope of the content of the present invention.

[0024] The terms used throughout the specification and claims generally have the ordinary meanings of each term used in the art, in this invention and in the specific context, unless otherwise noted.

[0025] As used herein, “coupled” or “connected” may refer to direct physical or electrical contact between two or more elements, or indirect physical or electrical contact between two or more elements, or may refer to mutual operation or action between two or more elements.

[0026] See also Figure 1 , Figure 1 FIG. 1 is a block diagram of a converter circuit 100 according to some embodiments of the present invention. Figure 1 In the present invention, the number indexes [1] to [4] are used to refer to individual components or signals, but this is not intended to limit the number of components or signals to a specific number. Figure 1 As shown, the converter circuit 100 includes a plurality of power stage circuits 10[1]-10[4] and a control circuit 12, wherein the control circuit 12 is electrically coupled to the plurality of power stage circuits 10[1]-10[4]. Specifically, the converter circuit 100 can be implemented by a multi-phase buck converter.

[0027] During operation of the converter circuit 100, the control circuit 12 is used to output a plurality of control signals PWM[1]-PWM[4] to the plurality of power stage circuits 10[1]-10[4]. The plurality of power stage circuits 10[1]-10[4] are used to output a plurality of output currents IL[1]-IL[4] according to the plurality of control signals PWM[1]-PWM[4].

[0028] In some embodiments, the output current IL of each power stage circuit 10 is output to the corresponding passive circuit. Figure 1 As shown, the output current IL[1] of the power stage circuit 10[1] is output to the inductor L[1] and the capacitor C[1] connected in series between the current output terminal of the power stage circuit 10[1] and the ground terminal. The output current IL[2] of the power stage circuit 10[2] is output to the inductor L[2] and the capacitor C[2] connected in series between the current output terminal of the power stage circuit 10[2] and the ground terminal. The output current IL[3] of the power stage circuit 10[3] is output to the inductor L[3] and the capacitor C[3] connected in series between the current output terminal of the power stage circuit 10[3] and the ground terminal. The output current IL[4] of the power stage circuit 10[4] is output to the inductor L[4] and the capacitor C[4] connected in series between the current output terminal of the power stage circuit 10[4] and the ground terminal.

[0029] In some embodiments, multiple temperature feedback terminals (not shown) of multiple power stage circuits 10[1]-10[4] are Figure 1 The control circuit 12 and the power stage circuits 10[1] to 10[4] are coupled to each other and to the control circuit 12, so that the control circuit 12 and the power stage circuits 10[1] to 10[4] can receive the maximum temperature value Thest of the power stage circuits 10[1] to 10[4]. The generation of the maximum temperature value Thest will be described in detail in the following paragraphs.

[0030] In some embodiments, the plurality of power stage circuits 10[1]-10[4] are used to respectively output a plurality of current sensing values ​​Isen[1]-Isen[4] corresponding to the plurality of output currents IL[1]-IL[4] to the control circuit 12, so that the control circuit 12 can perform a current balancing operation according to the plurality of output currents IL[1]-IL[4]. Figure 2A and Figure 2B The current balancing operation performed by the control circuit 12 is described.

[0031] See also Figure 2A and Figure 2B , Figure 2A is a schematic diagram of a current balancing operation performed by the control circuit 12 according to some embodiments of the present invention. Figure 2B FIG. 1 is a schematic diagram of adjusting the control signal PWM according to some embodiments of the present invention. In some embodiments, the control circuit 12 includes an averaging circuit 21, a comparison circuit 23, and a signal generating circuit 25, wherein the comparison circuit 23 is electrically coupled between the averaging circuit 21 and the signal generating circuit 25. Figure 2AAs shown, the averaging circuit 21 is used to receive a plurality of current sensing values ​​Isen[1]~Isen[4], and to average the plurality of current sensing values ​​Isen[1]~Isen[4] to generate a current average value Iavg. The comparison circuit 23 is used to receive the current average value Iavg and a plurality of current sensing values ​​Isen[1]~Isen[4], and to compare each of the plurality of current sensing values ​​Isen[1]~Isen[4] with the current average value Iavg to generate a plurality of comparison results to the signal generating circuit 25. Accordingly, the signal generating circuit 25 is used to adjust a plurality of control signals PWM[1]~PWM[4] according to the plurality of comparison results generated by the comparison circuit 23. For example, the comparison result between the current sensing value Isen[1] and the current average value Iavg is used to adjust the control signal PWM[1], the comparison result between the current sensing value Isen[2] and the current average value Iavg is used to adjust the control signal PWM[2], and so on. Furthermore, the plurality of control signals PWM[1]-PWM[4] are respectively used to control the magnitudes of the plurality of output currents IL[1]-IL[4] output by the plurality of power stage circuits 10[1]-10[4].

[0032] In the following embodiments, if only a component or signal number is used without specifying the index of the component or signal number, it means that the component or signal number refers to any unspecified one in the component group or signal group to which it belongs. For example, the control signal PWM refers to any unspecified one of the control signals PWM[1] to PWM[4]. In some embodiments, Figure 2B As shown, the control signal PWM is a pulse width modulation (PWM) signal and has a duty ratio DR[B] before being adjusted. In some embodiments, the comparison result generated by the comparison circuit 23 shows that the current sensing value Isen is less than the current average value Iavg, so that the signal generating circuit 25 increases the corresponding duty ratio DR[B] of the control signal PWM to another higher duty ratio DR[H]. In some embodiments, the comparison result generated by the comparison circuit 23 shows that the current sensing value Isen is greater than the current average value Iavg, so that the signal generating circuit 25 reduces the corresponding duty ratio DR[B] of the control signal PWM to another lower duty ratio DR[L].

[0033] Undertake Figure 2BIn the embodiment of the present invention, the higher the duty cycle DR of the control signal PWM, the greater the output current IL output by the power stage circuit 10 receiving the control signal PWM. The lower the duty cycle DR of the control signal PWM, the smaller the output current IL output by the power stage circuit 10 receiving the control signal PWM. In other words, when the current sensing value Isen is less than the current average value Iavg, the control circuit 12 increases the duty cycle DR of the control signal PWM to increase the output current IL of the power stage circuit 10. When the current sensing value Isen is greater than the current average value Iavg, the control circuit 12 reduces the duty cycle DR of the control signal PWM to reduce the output current IL of the power stage circuit 10.

[0034] As can be seen from the description of the above embodiment, the control circuit 12 is used to adjust the multiple control signals PWM[1]-PWM[4] according to the multiple current sensing values ​​Isen[1]-Isen[4], so as to change the values ​​of the multiple output currents IL[1]-IL[4]. After the multiple output currents IL[1]-IL[4] change, the multiple power stage circuits 10[1]-10[4] will update the multiple current sensing values ​​Isen[1]-Isen[4] of their outputs. In summary, based on this feedback control, the control circuit 12 will adjust the multiple control signals PWM[1]-PWM[4] multiple times according to the multiple current sensing values ​​Isen[1]-Isen[4] received from the multiple power stage circuits 10[1]-10[4], and then adjust the multiple output currents IL[1]-IL[4] multiple times until the multiple output currents IL[1]-IL[4] are substantially the same (that is, current balance is achieved).

[0035] Further explanation of the above embodiment is provided that, when the multiple power stage circuits 10[1] to 10[4] achieve current balance, the multiple power stage circuits 10[1] to 10[4] can theoretically also achieve temperature balance (i.e., the temperatures are substantially the same). However, in practice, the circuits are not ideal. When the multiple power stage circuits 10[1] to 10[4] achieve current balance, the heat dissipation capabilities of the multiple power stage circuits 10[1] to 10[4] may be affected by adjacent heat sources (e.g., circuits), so that temperature balance may not be achieved.

[0036] See also Figure 3 , Figure 3The block diagram of the power stage circuit 10 is shown according to some embodiments of the present invention. In some embodiments, the power stage circuit 10 includes a power circuit 31, a temperature sensing circuit 33, a current sensing circuit 35, and a current feedback control circuit 37. Specifically, the power circuit 31 is electrically coupled to the current output terminal LX of the power stage circuit 10. The current sensing circuit 35 is electrically coupled to the power circuit 31. The current feedback control circuit 37 is electrically coupled to the temperature sensing circuit 33, the current sensing circuit 35, the temperature feedback terminal Tmon of the power stage circuit 10, and the current feedback terminal Imon of the power stage circuit 10.

[0037] In addition, if Figure 3 As shown, the current feedback control circuit 37 includes a temperature comparison circuit 371 and a sensing value adjustment circuit 373. The temperature comparison circuit 371 is electrically coupled to the temperature sensing circuit 33 and the temperature feedback terminal Tmon at the first node N1 and the second node N2 respectively. The sensing value adjustment circuit 373 is electrically coupled to the current sensing circuit 35, the temperature comparison circuit 371 and the current feedback terminal Imon.

[0038] In some embodiments, the power circuit 31 is used to receive a control signal PWM, an input voltage VIN and a ground voltage GND, and is used to output an output current IL from a current output terminal LX according to the control signal PWM. The temperature sensing circuit 33 is used to sense the temperature of the power stage circuit 10 to output a temperature sensing value Tsen. The current sensing circuit 35 is used to sense the output current IL to output a current sensing value Isen corresponding to the output current IL. The temperature feedback terminal Tmon is used to receive a maximum temperature value Thest from the outside of the power stage circuit 10 (for example, other power stage circuits 10). The current feedback control circuit 37 is used to receive the temperature sensing value Tsen, the current sensing value Isen and the maximum temperature value Thest from the temperature sensing circuit 33, the current sensing circuit 35 and the temperature feedback terminal Tmon respectively, to output a current sensing value Isen or an adjusted current sensing value Isen_m. The current feedback terminal Imon is used to output the current sensing value Isen or the adjusted current sensing value Isen_m to the outside of the power stage circuit 10 (for example: Figure 1 The control circuit 12 in FIG.

[0039] In the above embodiment, the temperature sensing value Tsen and the maximum temperature value Thest are both transmitted in the form of a voltage signal, the temperature represented by the temperature sensing value Tsen is positively correlated with the voltage value of the voltage signal, and the temperature represented by the maximum temperature value Thest is also positively correlated with the voltage value of the voltage signal. When the temperature sensing value Tsen is less than the maximum temperature value Thest (that is, the voltage signal corresponding to the temperature sensing value Tsen has a voltage value less than the voltage signal corresponding to the maximum temperature value Thest), the temperature comparison circuit 371 continues to receive the maximum temperature value Thest from the outside of the power stage circuit 10 through the temperature feedback terminal Tmon. When the temperature sensing value Tsen is greater than or equal to the maximum temperature value Thest (that is, the voltage signal corresponding to the temperature sensing value Tsen has a voltage value greater than or equal to the voltage signal corresponding to the maximum temperature value Thest), the temperature comparison circuit 371 outputs the temperature sensing value Tsen to the outside of the power stage circuit 10 through the temperature feedback terminal Tmon. Furthermore, when at least one power stage circuit 10 outputs a temperature sensing value Tsen, since the temperature feedback terminals Tmon of the plurality of power stage circuits 10 are coupled to each other and to the control circuit 12 (eg Figure 1 As shown), the voltage signal with the highest voltage value will remain as the new maximum temperature value Thest (ie, the previous maximum temperature value Thest is replaced) and input to each power stage circuit 10 and the control circuit 12.

[0040] See also Figure 4 , Figure 4 The circuit diagram of the power stage circuit 10 is shown according to some embodiments of the present invention. In some embodiments, the power circuit 31 includes a high-side switch T1, a low-side switch T2 and a driving circuit 311. The first end of the high-side switch T1 is used to receive the input voltage VIN, the second end of the high-side switch T1 and the first end of the low-side switch T2 are coupled to the current output terminal LX, and the second end of the low-side switch T2 is used to receive the ground voltage GND. The driving circuit 311 is coupled to the control end of the high-side switch T1 and the control end of the low-side switch T2, respectively, to receive the control signal PWM, and to control the high-side switch T1 and the low-side switch T2 to be alternately turned on according to the control signal PWM, so as to generate an output current IL at the current output terminal LX. For example, if the duty cycle of the control signal PWM is 60%, it means that the control signal PWM is at an enable level for 60% of the time and at a disable level for 40% of the time in each cycle, and the enable level and the disable level of the control signal PWM are used to turn on the high-side switch T1 and the low-side switch T2 respectively. Specifically, the high-side switch T1 and the low-side switch T2 may be implemented by transistors (eg, metal oxide semiconductor (MOS) transistors).

[0041] In some embodiments, such as Figure 4 As shown, the current feedback control circuit 37 includes a switch circuit D1, an amplifier circuit A1 and an operation circuit C1. The first end of the switch circuit D1 is electrically coupled to the temperature sensing circuit 33 at a first node N1, and the second end of the switch circuit D1 is electrically coupled to the temperature feedback end Tmon at a second node N2. The first input end (at Figure 4 The first node N1 is electrically coupled to the first input terminal of the amplifier circuit A1 (indicated by the symbol “-” in FIG. Figure 4 The operation circuit C1 is electrically coupled to the current sensing circuit 35, the output terminal of the amplifier circuit A1 and the current feedback terminal Imon. Specifically, the switch circuit D1 can be implemented by a diode circuit, the amplifier circuit A1 can be implemented by an operational amplifier, and the operation circuit C1 can be implemented by an addition / subtraction circuit.

[0042] For further explanation, please also refer to Figure 3 and Figure 4 , Figure 4 The switch circuit D1 and amplifier circuit A1 in the embodiment can be used to realize Figure 3 The temperature comparison circuit 371 in the Figure 4 The operation circuit C1 in the Figure 3 The sensing value adjustment circuit 373 in.

[0043] Then match Figure 5 The temperature balancing method 500 is shown to detail the operation of the power stage circuit 10. Figure 5 , Figure 5 FIG. 5 is a flow chart of a temperature balancing method 500 according to some embodiments of the present invention. In some embodiments, Figure 5 As shown, the temperature balancing method 500 includes steps S501 - S503 .

[0044] In step S501, the temperature sensing value Tsen of the power stage circuit 10 is compared with the maximum temperature value Thest by the power stage circuit 10. In some embodiments, Figure 4 As shown, the switch circuit D1 and the amplifier circuit A1 receive the temperature sensing value Tsen from the temperature sensing circuit 33 via the first node N1, and receive the maximum temperature value Thest from the temperature feedback terminal Tmon via the second node N2 to compare the temperature sensing value Tsen with the maximum temperature value Thest. Figure 3 In the embodiment, the comparison between the temperature sensing value Tsen and the maximum temperature value Thest can be performed by comparing the voltage value of the voltage signal corresponding to the temperature sensing value Tsen with the voltage value of the voltage signal corresponding to the maximum temperature value Thest.

[0045] Thereafter, in step S502, the current sensing value Isen corresponding to the output current IL of the power stage circuit 10 is selectively adjusted according to the comparison result between the temperature sensing value Tsen and the maximum temperature value Thest by the power stage circuit 10. Figure 6 Step S502 is described. Figure 6 FIG. 4 is a schematic diagram of a current sensing value Isen and an adjusted current sensing value Isen_m according to some embodiments of the present invention.

[0046] In some embodiments, when the temperature sensing value Tsen is less than the maximum temperature value Thest, Figure 4 The switch circuit D1 in the circuit is in the turn-off state, so a first voltage difference is generated between the first node N1 and the second node N2, wherein the first voltage difference is a non-zero voltage difference (because the switch circuit D1 is in the turn-off state, and the voltage value of the first node N1 is less than the voltage value of the second node N2). The amplifier circuit A1 outputs the compensation value Icom according to the first voltage difference. For example, the amplifier circuit A1 amplifies the first voltage difference to generate the compensation value Icom. The operation circuit C1 reduces the current sensing value Isen by the compensation value Icom. For example, the operation circuit C1 subtracts the compensation value Icom from the current sensing value Isen to generate an adjusted current sensing value Isen_m (such as Figure 6 Furthermore, the operation circuit C1 outputs the lower adjusted current sensing value Isen_m to the current feedback terminal Imon.

[0047] In some embodiments, when the temperature sensing value Tsen is greater than or substantially equal to the maximum temperature value Thest, Figure 4 The switch circuit D1 in the circuit is in the turn-on state, so a second voltage difference is generated between the first node N1 and the second node N2, wherein the second voltage difference is a zero voltage difference (because the switch circuit D1 is in the turn-on state). In other words, the first node N1 and the second node N2 are short-circuited in this case. The amplifier circuit A1 outputs a compensation value Icom with a value of zero according to the second voltage difference, so that the operation circuit C1 still generates a current sensing value Isen after subtracting the compensation value Icom from the current sensing value Isen. Therefore, it can also be understood that the operation circuit C1 directly outputs the current sensing value Isen (such as Figure 6 shown).

[0048] As can be seen from the description of step S501 and step S502, the current feedback control circuit 37 compares the temperature sensing value Tsen with the maximum temperature value Thest through the temperature comparison circuit 371 (i.e., the switch circuit D1 and the amplifier circuit A1), and outputs one of the current sensing value Isen and the adjusted current sensing value Isen_m to the current feedback terminal Imon through the sensing value adjustment circuit 373 (i.e., the operation circuit C1) according to the comparison result between the temperature sensing value Tsen and the maximum temperature value Thest.

[0049] In step S503, the control circuit 12 controls the current sensing value (eg: Figure 6 The control signal PWM is adjusted according to the current sensing value Isen or the adjusted current sensing value Isen_m, so that the value of the output current IL of the power stage circuit 10 changes. The description of step S503 is similar to the description of the above-mentioned current balancing operation, so it is not repeated here. Figure 5 As shown, after step S503 , the converter circuit 100 may execute steps S501 - S503 again.

[0050] Then based on Figure 1 The architecture of the converter circuit 100 is described with some specific values ​​as an example to illustrate the temperature balancing method 500. In some assumptions, the multiple current sensing values ​​Isen[1]~Isen[4] sensed by the multiple power stage circuits 10[1]~10[4] are all 10 amperes (A). Under non-ideal conditions, the temperature sensing value Tsen of the power stage circuit 10[1] is 67 degrees, the temperature sensing value Tsen of the power stage circuit 10[2] is 72 degrees, the temperature sensing value Tsen of the power stage circuit 10[3] is 85 degrees, and the temperature sensing value Tsen of the power stage circuit 10[4] is 70 degrees. It can be seen that the highest temperature value Thest of the multiple power stage circuits 10[1]~10[4] is 85 degrees.

[0051] Following the above description, since the temperature sensing value Tsen of the power stage circuit 10[3] is equal to the maximum temperature value Thest, the power stage circuit 10[3] directly outputs a current sensing value Isen[3] of 10 amperes to the control circuit 12 (corresponding to step S502). In addition, assume that the compensation value Icom is 3. Since the temperature sensing value Tsen of the power stage circuit 10[1], the temperature sensing value Tsen of the power stage circuit 10[2] and the temperature sensing value Tsen of the power stage circuit 10[4] are all less than the maximum temperature value Thest, the power stage circuit 10[1], the power stage circuit 10[2] and the power stage circuit 10[4] adjust the current sensing value Isen[1], the current sensing value Isen[2] and the current sensing value Isen[4] from 10 amperes to 7 amperes according to the compensation value Icom and output them to the control circuit 12 (corresponding to step S502). Incidentally, this current sensing value of 7 amperes is the aforementioned Figure 3 and Figure 4 In addition, it should be understood that the compensation value Icom of 3 is only an example and convenient for explanation. In practice, different compensation values ​​Icom may be used to adjust the current sensing value Isen[1], the current sensing value Isen[2], and the current sensing value Isen[4] respectively according to the different temperature sensing values ​​Tsen of the power stage circuit 10[1], the power stage circuit 10[2], and the power stage circuit 10[4].

[0052] Thereafter, corresponding to step S503, the control circuit 12 calculates that the current average value Iavg is 7.75 amperes, determines that the current sensing values ​​Isen[1], Isen[2], and Isen[4] are all less than the current average value Iavg, and determines that the current sensing value Isen[3] is greater than the current average value Iavg. Figure 2A and Figure 2B As can be seen from the description, the control circuit 12 increases the duty cycle DR of the control signal PWM[1], the control signal PWM[2] and the control signal PWM[4], and reduces the duty cycle DR of the control signal PWM[3].

[0053] Accordingly, the current sensing value Isen[1] sensed by the power stage circuit 10[1], the current sensing value Isen[2] sensed by the power stage circuit 10[2], and the current sensing value Isen[4] sensed by the power stage circuit 10[4] all change from 10 amps to 11 amps, and the current sensing value Isen[3] sensed by the power stage circuit 10[3] changes from 10 amps to 7 amps. Due to the changes in the multiple output currents IL[1] to IL[4], the temperature sensing value Tsen of the power stage circuit 10[1] changes to 70 degrees, the temperature sensing value Tsen of the power stage circuit 10[2] changes to 74 degrees, the temperature sensing value Tsen of the power stage circuit 10[3] changes to 79 degrees, and the temperature sensing value Tsen of the power stage circuit 10[4] changes to 72 degrees. It can be seen that the temperature difference between the multiple power stage circuits 10[1] to 10[4] has become smaller.

[0054] In the above description, since the temperature of the power stage circuit 10[3] is still the highest, the converter circuit 100 will repeat the above operation again to further reduce the temperature difference between the multiple power stage circuits 10[1] to 10[4]. Finally, the multiple power stage circuits 10[1] to 10[4] will reach temperature balance.

[0055] At Figure 4 In the embodiment of FIG. 1 , the amplifier circuit A1 is preset to have a gain, and the gain is not adjusted during the operation of the power stage circuit 10 . However, the present invention is not limited thereto.

[0056] See also Figure 7 , Figure 7 FIG. 1 is a circuit diagram of a power stage circuit 10 according to some embodiments of the present invention. Figure 7 Zhongyu Figure 4 The same or similar components or signals are represented by the same symbols and will not be described again here. Figure 7 In the embodiment of the present invention, the temperature sensing value Tsen is output to the inside of the amplifier circuit A1, so that the amplifier circuit A1 adjusts the gain according to the temperature sensing value Tsen. In some embodiments, the gain is negatively correlated with the temperature sensing value Tsen. For example, the gain decreases as the temperature sensing value Tsen increases, and increases as the temperature sensing value Tsen decreases. Generally speaking, the larger the temperature sensing value Tsen is, the closer the temperature of the power stage circuit 10 is to the maximum temperature value Thest, and there is no need to adjust the current sensing value Isen and / or the output current IL too much.

[0057] See also Figure 8 , Figure 8 FIG. 1 is a circuit diagram of a power stage circuit 10 according to some embodiments of the present invention. Figure 8 Zhongyu Figure 4The same or similar components or signals are represented by the same symbols and will not be described again here. Figure 8 In the embodiment of the present invention, the current sensing value Isen is output to the inside of the amplifier circuit A1, so that the amplifier circuit A1 adjusts the gain according to the current sensing value Isen. In some embodiments, the gain is negatively correlated with the current sensing value Isen. For example, the gain decreases as the current sensing value Isen increases, and increases as the current sensing value Isen decreases. Generally speaking, the larger the current sensing value Isen is, the closer the temperature of the power stage circuit 10 is to the maximum temperature value Thest, and there is no need to adjust the current sensing value Isen and / or the output current IL too much.

[0058] From the above-mentioned implementation of the present invention, it can be known that the power stage circuit 10 selectively adjusts the current sensing value Isen according to the comparison result of the temperature sensing value Tsen and the maximum temperature value Thest. The converter circuit 100 of the present invention can automatically control multiple power stage circuits 10 to achieve temperature balance without manual adjustment by the user.

[0059] As used herein, "about", "approximately" or "roughly" generally refers to an error or range of a numerical value within 20%, preferably within 10%, and more preferably within 5%. If there is no explicit explanation in the text, the numerical values ​​mentioned are all regarded as approximate values, that is, the error or range represented by "about", "approximately" or "roughly about".

[0060] Although the contents of the present invention have been disclosed as above in the form of implementation methods, they are not intended to limit the contents of the present invention. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the contents of the present invention. Therefore, the scope of protection of the contents of the present invention shall be determined by the definition of the appended claims.

[0061]

Explanation of symbols

[0062] 10: Power stage circuit

[0063] 12: Control circuit

[0064] 21: Average Circuit

[0065] 23: Comparison Circuit

[0066] 25:Signal generating circuit

[0067] 31: Power Circuit

[0068] 33: Temperature sensing circuit

[0069] 35: Current sensing circuit

[0070] 37: Current feedback control circuit

[0071] 100:Converter circuit

[0072] 311: Driving circuit

[0073] 371: Temperature comparison circuit

[0074] 373: Sensing value adjustment circuit

[0075] 500: Temperature balance method

[0076] A1: Amplifier circuit

[0077] C: Capacitor

[0078] C1: Operation circuit

[0079] D1: Switching circuit

[0080] DR: Duty cycle

[0081] GND: Ground voltage

[0082] IL: Output current

[0083] Iavg: average current

[0084] Icom: Compensation value

[0085] Imon: Current feedback terminal

[0086] Isen, Isen_m: current sensing value

[0087] L: Inductance

[0088] LX: Current output terminal

[0089] N1: First Node

[0090] N2: Second node

[0091] PWM: control signal

[0092] S501~S503: Steps

[0093] T1: High-side switch

[0094] T2: Low-side switch

[0095] Thest: Maximum temperature value

[0096] Tmon: Temperature feedback terminal

[0097] Tsen: Temperature sensing value

[0098] VIN: input voltage.

Claims

1. A converter circuit, characterized in that: include: A plurality of power stage circuits, configured to output a plurality of output currents according to a plurality of control signals, and to selectively adjust a plurality of current sensing values ​​corresponding to the plurality of output currents according to a comparison result of a plurality of temperature sensing values ​​of the plurality of power stage circuits and a maximum temperature value of the plurality of power stage circuits; as well as The control circuit is electrically coupled to the multiple power stage circuits, and is used to output the multiple control signals to the multiple power stage circuits, to receive the multiple current sensing values ​​from the multiple power stage circuits, and to adjust the multiple control signals according to the multiple current sensing values ​​so that the magnitudes of the multiple output currents change.

2. The converter circuit according to claim 1, characterized in that Each of the plurality of power stage circuits is used to reduce and output a corresponding one of the plurality of current sensing values ​​when a corresponding one of the plurality of temperature sensing values ​​is less than the highest temperature value; Each of the plurality of power stage circuits is configured to directly output the corresponding one of the plurality of current sensing values ​​when the corresponding one of the plurality of temperature sensing values ​​is equal to the highest temperature value.

3. The converter circuit according to claim 1, characterized in that Each of the plurality of power stage circuits further comprises: A power circuit, configured to output corresponding ones of the plurality of output currents according to corresponding ones of the plurality of control signals; A temperature sensing circuit, used to sense the temperature of a corresponding one of the plurality of power stage circuits to output a corresponding one of the plurality of temperature sensing values; A current sensing circuit, configured to sense the corresponding one of the plurality of output currents to output the corresponding one of the plurality of current sensing values; Temperature feedback terminal; Current feedback terminal; as well as A current feedback control circuit is electrically coupled to the temperature sensing circuit, the current sensing circuit, the temperature feedback end and the current feedback end, and is used to compare the corresponding one of the multiple temperature sensing values ​​with the highest temperature value, and to selectively adjust the corresponding one of the multiple current sensing values ​​according to the comparison result of the corresponding one of the multiple temperature sensing values ​​with the highest temperature value.

4. The converter circuit according to claim 3, characterized in that The current feedback control circuit comprises: A temperature comparison circuit is electrically coupled to the temperature sensing circuit and the temperature feedback terminal at a first node and a second node respectively, and is used to compare the corresponding one of the plurality of temperature sensing values ​​with the highest temperature value; as well as The sensing value adjustment circuit is electrically coupled to the current sensing circuit, the temperature comparison circuit and the current feedback end, and is used to output the corresponding one of the multiple current sensing values ​​or the corresponding one of the multiple current sensing values ​​after adjustment to the current feedback end.

5. The converter circuit according to claim 4, characterized in that In a case where the corresponding one of the plurality of temperature sensing values ​​is less than the highest temperature value, the temperature comparison circuit outputs a compensation value according to a first voltage difference generated between the first node and the second node, and the sensing value adjustment circuit reduces the corresponding one of the plurality of current sensing values ​​by the compensation value, and outputs the reduced corresponding one of the plurality of current sensing values; When the corresponding one among the multiple temperature sensing values ​​is equal to the highest temperature value, the temperature comparison circuit outputs the compensation value with a value of zero according to the second voltage difference generated between the first node and the second node, and the sensing value adjustment circuit directly outputs the corresponding one among the multiple current sensing values.

6. A power stage circuit, characterized in that: Include: A power circuit for outputting an output current according to a control signal; A temperature sensing circuit, used to sense the temperature of the power stage circuit to output a temperature sensing value; A current sensing circuit, electrically coupled to the power circuit, and used to sense the output current to output a current sensing value; Temperature feedback terminal, used to receive the maximum temperature value; Current feedback terminal; as well as The current feedback control circuit is electrically coupled to the temperature sensing circuit, the current sensing circuit, the temperature feedback end and the current feedback end, and is used to compare the temperature sensing value with the maximum temperature value, and to output one of the current sensing value and the adjusted current sensing value to the current feedback end according to the comparison result between the temperature sensing value and the maximum temperature value.

7. The power stage circuit according to claim 6, characterized in that: The current feedback control circuit comprises: A switch circuit, wherein a first end of the switch circuit and the temperature sensing circuit are electrically coupled to a first node, and a second end of the switch circuit and the temperature feedback end are electrically coupled to a second node; an amplifier circuit, wherein a first input terminal of the amplifier circuit is electrically coupled to the first node, and a second input terminal of the amplifier circuit is electrically coupled to the second node; as well as The operation circuit is electrically coupled to the current sensing circuit, the output end of the amplifier circuit and the current feedback end.

8. The power stage circuit according to claim 7, characterized in that: When the temperature sensing value is less than the maximum temperature value, the switch circuit is in an off state to generate a first voltage difference between the first node and the second node, the amplifier circuit outputs a compensation value according to the first voltage difference, and the operation circuit reduces the current sensing value by the compensation value, and outputs the reduced current sensing value to the current feedback terminal; When the temperature sensing value is equal to the maximum temperature value, the switch circuit is in an on state to generate a second voltage difference between the first node and the second node, the amplifier circuit outputs the compensation value of zero according to the second voltage difference, and the operation circuit directly outputs the current sensing value.

9. A temperature balancing method, characterized in that: The invention is applied to a converter circuit, wherein the converter circuit comprises a plurality of power stage circuits and a control circuit, the plurality of power stage circuits are used to output a plurality of output currents according to a plurality of control signals output by the control circuit, and the temperature balancing method comprises: By means of the plurality of power stage circuits, comparing the plurality of temperature sensing values ​​of the plurality of power stage circuits with the highest temperature value of the plurality of power stage circuits; By means of the plurality of power stage circuits, selectively adjusting a plurality of current sensing values ​​corresponding to the plurality of output currents according to a comparison result between the plurality of temperature sensing values ​​and the highest temperature value; as well as The control circuit adjusts the control signals according to the current sensing values, so that the magnitudes of the output currents are changed.

10. The temperature balancing method according to claim 9, characterized in that: The step of selectively adjusting the plurality of current sensing values ​​according to the comparison results between the plurality of temperature sensing values ​​and the highest temperature value comprises: When a corresponding one of the plurality of temperature sensing values ​​is less than the highest temperature value, reducing and outputting a corresponding one of the plurality of current sensing values; as well as In a case where the corresponding one of the plurality of temperature sensing values ​​is equal to or greater than the highest temperature value, the corresponding one of the plurality of current sensing values ​​is directly output.

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