Secondary slope compensation current generation circuit and electronic equipment

Abstract

The invention provides a secondary slope compensation current generation circuit and electronic equipment, a primary slope compensation current generation module generates a corresponding primary slope compensation current according to a received switching signal, so that a first current pulling module pulls a first reference current from a secondary slope compensation current generation module; the first reference current corresponds to the primary slope compensation current; the second current pulling module provides a second reference current for the secondary slope compensation current generation module; and the secondary slope compensation current generation module outputs secondary slope compensation current according to the first reference current and the second reference current, and the secondary slope compensation current and the primary slope compensation current meet a corresponding quadratic term relationship. The slope current with the fixed slope is changed into the quadratic slope compensation current, so that the compensation of the slope current has small influence on the maximum peak current of the inductor under the condition of small duty ratio, and the transient response and the maximum loading capacity of the system are improved.

Description

Technical Field

[0001] The present invention relates to the field of power supplies, and in particular to a secondary slope compensation current generating circuit and electronic equipment. Background Art

[0002] Traditional slope compensation technology is mainly fixed slope compensation. Although this solution can achieve the purpose of compensation (stabilizing the current loop), this slope compensation mechanism generally uses a single slope compensation slope, and the compensation amount is relatively fixed, which easily causes over-compensation under small duty cycle. Over-compensation limits the transient response and maximum load capacity of the system, causing the system transient response to deteriorate and affecting the normal operation of the system.

[0003] On this basis, how to achieve a smaller compensation current at a smaller duty cycle, while the compensation current increases rapidly when the duty cycle increases, has become a difficult problem that troubles those skilled in the art. Summary of the invention

[0004] The object of the present invention is to provide a secondary slope compensation current generating circuit and an electronic device to improve the above-mentioned problem.

[0005] In order to achieve the above purpose, the technical solution adopted by the embodiment of the present invention is as follows:

[0006] In a first aspect, an embodiment of the present invention provides a secondary slope compensation current generating circuit, the secondary slope compensation current generating circuit comprising: a primary slope compensation current generating module, a first current pulling module, a second current pulling module and a secondary slope compensation current generating module;

[0007] The primary slope compensation current generating module is connected to the first current pulling module, the first current pulling module is connected to the secondary slope compensation current generating module, and the secondary slope compensation current generating module is also connected to the second current pulling module;

[0008] The primary slope compensation current generating module is used to generate a corresponding primary slope compensation current according to the received switch signal, so that the first current pulling module pulls a first reference current from the secondary slope compensation current generating module, and the first reference current corresponds to the primary slope compensation current;

[0009] The second current pulling module is used to provide a second reference current to the secondary slope compensation current generating module;

[0010] The secondary slope compensation current generating module is used for outputting a secondary slope compensation current according to the first reference current and the second reference current, and the secondary slope compensation current satisfies a corresponding quadratic term relationship with the primary slope compensation current.

[0011] In a second aspect, an embodiment of the present invention provides an electronic device, comprising the above-mentioned secondary slope compensation current generating circuit.

[0012] Compared with the prior art, an embodiment of the present invention provides a secondary slope compensation current generating circuit and an electronic device, wherein the secondary slope compensation current generating circuit comprises: a primary slope compensation current generating module, a first current pulling module, a second current pulling module and a secondary slope compensation current generating module; the primary slope compensation current generating module is connected to the first current pulling module, the first current pulling module is connected to the secondary slope compensation current, and the secondary slope compensation current is also connected to the second current pulling module; the primary slope compensation current generating module is used to generate a corresponding primary slope compensation current according to a received switch signal, so that the first current pulling module pulls a first reference current from the secondary slope compensation current generating module, and the first reference current corresponds to the primary slope compensation current; the second current pulling module is used to provide a second reference current to the secondary slope compensation current generating module; the secondary slope compensation current generating module is used to output a secondary slope compensation current according to the first reference current and the second reference current, and the secondary slope compensation current satisfies a corresponding quadratic term relationship with the primary slope compensation current. The fixed slope ramp current is changed into a quadratic ramp compensation current, so that the slope current compensation has less influence on the maximum peak current of the inductor when the duty cycle is small, thereby improving the transient response and maximum load capacity of the system.

[0013] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0015] Figure 1 This is one of the structural schematic diagrams of the secondary slope compensation current generating circuit provided in an embodiment of the present invention.

[0016] Figure 2 A schematic diagram of a primary slope compensation current provided by an embodiment of the present invention.

[0017] Figure 3 The second structural schematic diagram of the secondary slope compensation current generating circuit provided in an embodiment of the present invention.

[0018] Figure 4A schematic diagram of a comparison between the current IO and the current I1 provided in an embodiment of the present invention.

[0019] Figure 5 The third structural schematic diagram of the secondary slope compensation current generating circuit provided in an embodiment of the present invention.

[0020] In the figure: 10 - primary slope compensation current generating module; 20 - first current pulling module; 30 - second current pulling module; 40 - secondary slope compensation current generating module; 41 - output unit; 42 - feedback unit. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. At the same time, in the description of the present invention, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0024] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0025] In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are directions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0026] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0028] In a current-mode controlled DCDC switching power supply, the control loop of the fixed slope compensation limits the maximum inductor current that can be achieved under different duty cycles. An embodiment of the present invention provides a secondary slope compensation current generating circuit, which is used to achieve the purpose of having a smaller compensation current at a smaller duty cycle and rapidly increasing the compensation current when the duty cycle increases.

[0029] Please refer to Figure 1 , Figure 1 This is one of the structural schematic diagrams of the secondary slope compensation current generating circuit provided in an embodiment of the present invention.

[0030] The secondary slope compensation current generating circuit comprises: a primary slope compensation current generating module 10 , a first current pulling module 20 , a second current pulling module 30 and a secondary slope compensation current generating module 40 .

[0031] The primary slope compensation current generating module 10 is connected to the first current pulling module 20 , the first current pulling module 20 is connected to the secondary slope compensation current generating module 40 , and the secondary slope compensation current generating module 40 is also connected to the second current pulling module 30 .

[0032] The primary slope compensation current generating module 10 is used to generate a corresponding primary slope compensation current according to the received switch signal, so that the first current pulling module 20 pulls a first reference current from the secondary slope compensation current generating module 40, and the first reference current corresponds to the primary slope compensation current.

[0033] It should be noted that the primary slope compensation current is a fixed slope compensation current corresponding to the duty cycle of the switching signal. Figure 2 , Figure 2 A schematic diagram of a primary slope compensation current provided by an embodiment of the present invention. In the figure, SW represents a switch signal, D represents a duty cycle corresponding to the SW switch signal, and I1 represents a primary slope compensation current. The primary slope compensation current generating module 10 generates a primary slope compensation current I1 by performing a logic operation on a fixed slope current and a SW switch signal in a switching power supply, and the primary slope compensation current is related to the duty cycle D.

[0034] The second current drawing module 30 is used to provide a second reference current to the secondary slope compensation current generating module 40 .

[0035] The secondary slope compensation current generating module 40 is used to output a secondary slope compensation current according to the first reference current, the second reference current and the feedback current. The secondary slope compensation current satisfies the corresponding quadratic term relationship with the primary slope compensation current, and the feedback current is proportional to the secondary slope compensation current.

[0036] The secondary slope compensation current generating circuit provided in the embodiment of the present invention changes the slope current with a fixed slope into a quadratic slope compensation current, so that the slope current compensation has a smaller impact on the maximum peak current of the inductor when the duty cycle is small, thereby improving the transient response and maximum load capacity of the system.

[0037] exist Figure 1 Based on the specific structure of the secondary slope compensation current generating module, the embodiment of the present invention also provides an optional implementation method, please refer to Figure 3 , Figure 3 The second structural schematic diagram of the secondary slope compensation current generating circuit provided in an embodiment of the present invention.

[0038] The secondary slope compensation current generating module 40 includes a first PMOS transistor M1 , a second PMOS transistor M2 , a third PMOS transistor M3 , a fourth PMOS transistor M4 , an output unit 41 and a feedback unit 42 .

[0039] The source of the second PMOS tube M2 is used to access the voltage source (VIN), and the drain of the second PMOS tube M2 is connected to the source of the first PMOS tube M1 and the gate of the second PMOS tube M2.

[0040] The gate of the first PMOS transistor M1 is connected to the drain of the first PMOS transistor M1 and the gate of the third PMOS transistor M3 , and the drain of the first PMOS transistor M1 is connected to the first end of the feedback unit 42 .

[0041] A connection terminal is led out between the first end of the feedback unit 42 and the first PMOS tube M1, and connected to the pull-down end of the first current pull module 20 (the pull-down current is the first reference current I2) and the pull-down end of the second current pull module 30 (the pull-down current is the second reference current IFS).

[0042] The source of the third PMOS transistor M3 is connected to the output end of the second current pulling module 30 (the output current is the second reference current IFS), and the drain of the third PMOS transistor M3 is grounded.

[0043] The source of the fourth PMOS transistor M4 is used to access the voltage source (VIN), the gate of the fourth PMOS transistor M4 is connected to the source of the third PMOS transistor M3 , and the drain of the fourth PMOS transistor M4 is connected to the second end of the feedback unit 42 .

[0044] The first end of the output unit 41 is used to access the voltage source (VIN), the second end of the output unit 41 is connected to the gate of the fourth PMOS tube M4, and the third end of the output unit 41 is connected to the output end of the secondary slope compensation current generating module 40.

[0045] The output unit 41 is used to output a corresponding secondary slope compensation current following the gate voltage of the fourth PMOS transistor M4 .

[0046] The feedback unit 42 is used to generate a corresponding feedback current according to the current flowing through the fourth PMOS transistor M4 , wherein the feedback current is proportional to the current flowing through the fourth PMOS transistor M4 , and the current flowing through the fourth PMOS transistor M4 is proportional to the secondary slope compensation current.

[0047] Please continue to refer to Figure 3 In an optional implementation, the output unit 41 includes a fifth PMOS tube M5, and the feedback unit 42 includes a sixth NMOS tube M6 and a seventh NMOS tube M7.

[0048] The drain of the sixth NMOS tube M6 serves as the first end of the feedback unit 42 , the drain of the first PMOS tube M1 is connected to the drain of the sixth NMOS tube M6 , the gate of the sixth NMOS tube M6 is connected to the gate of the seventh NMOS tube M7 , and the source of the sixth NMOS tube M6 is grounded.

[0049] A connection terminal is led out between the sixth NMOS transistor M6 and the first PMOS transistor M1 and connected to the pull-down end of the first current pulling module 20 (the pull-down current is the first reference current I2) and the pull-down end of the second current pulling module 30 (the pull-down current is the second reference current IFS).

[0050] The drain of the seventh NMOS transistor M7 serves as the second end of the feedback unit 42 , the drain of the fourth PMOS transistor M4 is connected to the drain of the seventh NMOS transistor M7 , and the source of the seventh NMOS transistor M7 is grounded.

[0051] The source of the fifth PMOS transistor M5 is used to access the voltage source (VIN), the gate of the fifth PMOS transistor M5 is connected to the gate of the fourth PMOS transistor M4 , and the drain of the fifth PMOS transistor M5 is connected to the output end of the secondary slope compensation current generating module 40 .

[0052] like Figure 3 As shown, the fourth PMOS tube M4 and the fifth PMOS tube M5 form a current mirror, the current flowing through the fourth PMOS tube M4 is IO, the current flowing through the fifth PMOS tube M5 is K×IO, and K is the current correlation coefficient between the fourth PMOS tube M4 and the fifth PMOS tube M5.

[0053] like Figure 3 As shown, the current flowing through the fourth PMOS tube M4 is the same as the current flowing through the seventh NMOS tube M7, both are 10. The sixth NMOS tube M6 and the seventh NMOS tube M7 form a current mirror, that is, the current flowing through the sixth NMOS tube M6 is the same as the current flowing through the seventh NMOS tube M7, both are 10.

[0054] like Figure 3 As shown, the drain of the first PMOS tube M1 is respectively connected to the pull-down end of the first current pulling module 20 (the pull-down current is the first reference current I2), the pull-down end of the second current pulling module 30 (the pull-down current is the second reference current IFS) and the drain of the sixth NMOS tube M6 (the current flowing through is IO), so the current IM1 flowing through the drain of the first PMOS tube M1 is the sum of the first reference current I2, the second reference current IFS and the current IO, that is, IM1=IFS+IO+I2.

[0055] From the current formula of MOS tube, we can know Among them, V gs Represents the voltage between the gate and source of the MOS tube, V th Indicates the voltage threshold corresponding to the MOS tube, I ds Indicates the current flowing through the drain and source of the MOS tube, K p It represents a fixed coefficient, which is determined by the process. W / L represents the width-to-length ratio of the MOS tube.

[0056] refer to Figure 3 , we can get V gs1 +V gs2 =V gs3 +V gs4 , where V gsirepresents the voltage between the gate and the source of the i-th PMOS tube (Mi). Optionally, the V th The first PMOS tube M1 and the second PMOS tube M2 have the same width-to-length ratio, and the first PMOS tube M1 and the second PMOS tube M2 have the same width-to-length ratio.

[0057] Therefore, the above formula can be rewritten as a current expression:

[0058]

[0059] Wherein, IMi represents the current flowing through the drain and source of the i-th PMOS tube, and Ki represents the width-to-length ratio of the i-th PMOS tube.

[0060] After transformation, we can know that:

[0061]

[0062] Combination Figure 3 It can be seen that IM3 = the second reference current IFS, IM4 = IO;

[0063] IM1=IFS+IO+I2. After conversion, we can know the corresponding conversion relationship between I2 and IO.

[0064] Because the first reference current I2 corresponds to the primary slope compensation current I1, after determining the corresponding conversion relationship between I2 and IO, the corresponding conversion relationship between the primary slope compensation current I1 and IO can be determined. When I2 = 2 × I1, we can get

[0065] Right now

[0066] It can be seen from the above that there is a slope relationship between the current IO flowing through the fourth PMOS transistor and the primary slope compensation current I1.

[0067] In an optional implementation, the width-to-length ratio of the first PMOS tube M1 and the width-to-length ratio of the second PMOS tube M2 is 4:1; the width-to-length ratio of the third PMOS tube M3 and the width-to-length ratio of the fourth PMOS tube M4 is 1:1, and I2=2×I1.

[0068] Right now And IM1=IFS+IO+2×I1, we can get IO=I1 2 / IFS, realizes the square relationship between the output current IO and the input current I1.

[0069] Please refer to Figure 4 , Figure 4A schematic diagram of a comparison between the current IO and the current I1 provided in an embodiment of the present invention.

[0070] In an optional implementation, the second reference current IFS may be a maximum value of the primary slope compensation current I1.

[0071] exist Figure 3 On this basis, the embodiment of the present invention also provides an optional implementation method for further improving the matching effect of the current mirror in the secondary slope compensation current generating circuit, reducing the deviation of the drain end of the MOS tube in the current mirror, and ensuring the stability of the output current of the secondary slope compensation current generating circuit. Please refer to Figure 5 , Figure 5 The third structural schematic diagram of the secondary slope compensation current generating circuit provided in an embodiment of the present invention.

[0072] The secondary slope compensation current generating module 40 further includes an eighth NMOS transistor M8 and a ninth PMOS transistor M9.

[0073] The drain and gate of the eighth NMOS tube M8 are connected to the drain of the third PMOS tube M3 , and the source of the eighth NMOS tube M8 is grounded.

[0074] The source of the ninth PMOS tube M9 is connected to the drain of the fourth PMOS tube M4 , the gate of the ninth PMOS tube M9 is connected to the drain of the ninth PMOS tube M9 , and the drain of the ninth PMOS tube M9 is connected to the drain of the seventh NMOS tube.

[0075] On the basis of the above, in order to prevent the external interference signal from affecting the secondary slope compensation current generating circuit, the embodiment of the present invention also provides an optional implementation method. Please continue to refer to Figure 5 The secondary slope compensation current generating module 40 further includes a tenth PMOS transistor M10. The ninth PMOS transistor M9 and the tenth PMOS transistor M10 form a current mirror structure.

[0076] The source of the tenth PMOS tube M10 is connected to the drain of the fifth PMOS tube M5, the gate of the tenth PMOS tube M10 is connected to the gate of the ninth PMOS tube M9, and the drain of the tenth PMOS tube M10 serves as the output end of the secondary slope compensation current generating module 40. The tenth PMOS tube M10 is used to filter external noise interference.

[0077] Please continue to refer to Figure 3 Regarding the specific structure of the first current pulling module, the embodiment of the present invention also provides an optional implementation.

[0078] The first current pulling module 20 includes an eleventh PMOS transistor M11 , a twelfth PMOS transistor M12 , a thirteenth NMOS transistor M13 and a fourteenth NMOS transistor M14 .

[0079] The source of the eleventh PMOS transistor M11 and the source of the twelfth PMOS transistor M12 are used to access a voltage source (VIN).

[0080] The gate of the eleventh PMOS transistor M11 is connected to the gate of the twelfth PMOS transistor M12 and the drain of the eleventh PMOS transistor M11 , and the drain of the eleventh PMOS transistor M11 is connected to the pull-down end of the primary slope compensation current generating module 10 .

[0081] It should be noted that the pull-down current of the primary slope compensation current generating module 10 is the primary slope compensation current (I1). The eleventh PMOS transistor M11 and the twelfth PMOS transistor M12 form a current mirror, and the currents flowing through the two are equal or related.

[0082] The drain of the twelfth PMOS tube M12 is connected to the drain of the thirteenth NMOS tube M13, the drain of the thirteenth NMOS tube M13 is connected to the gate of the thirteenth NMOS tube M13, the gate of the thirteenth NMOS tube M13 is connected to the gate of the fourteenth NMOS tube M14, and the source of the thirteenth NMOS tube M13 and the source of the fourteenth NMOS tube M14 are grounded.

[0083] The drain of the fourteenth NMOS transistor M14 serves as a pull-down end of the first current pulling module 20 and is connected between the sixth NMOS transistor M6 and the first PMOS transistor M1 .

[0084] The current flowing through the twelfth PMOS tube M12 is equal to the current flowing through the thirteenth NMOS tube M13. The thirteenth NMOS tube M13 and the fourteenth NMOS tube M14 form a current mirror, and the currents flowing through the two are equal or related. The current flowing through the fourteenth NMOS tube M14 is the first reference current.

[0085] Please continue to refer to Figure 3 Regarding the specific structure of the second current pulling module, the embodiment of the present invention also provides an optional implementation.

[0086] The second current pulling module 30 includes a fifteenth NMOS transistor M15, a sixteenth NMOS transistor M16, a seventeenth PMOS transistor M17, an eighteenth PMOS transistor M18 and a nineteenth NMOS transistor M19.

[0087] The drain of the fifteenth NMOS tube M15 is used to access the second reference power supply (IFS shown in the figure), the drain of the fifteenth NMOS tube M15 is connected to the gate of the fifteenth NMOS tube M15, and the gate of the fifteenth NMOS tube M15 is connected to the gate of the sixteenth NMOS tube M16 and the gate of the nineteenth NMOS tube M19, and the source of the fifteenth NMOS tube M15, the source of the sixteenth NMOS tube M16 and the source of the nineteenth NMOS tube M19 are grounded.

[0088] The fifteenth NMOS transistor M15, the sixteenth NMOS transistor, and the nineteenth NMOS transistor M19 form a current mirror, and the currents flowing through the three transistors are equal, which are all the second reference current IFS.

[0089] The drain of the sixteenth NMOS tube M16 is connected to the drain of the seventeenth PMOS tube M17, the source of the seventeenth PMOS tube M17 and the source of the eighteenth PMOS tube M18 are used to access the voltage source (VIN), and the gate of the seventeenth PMOS tube M17 is connected to the drain of the seventeenth PMOS tube M17 and the gate of the eighteenth PMOS tube M18.

[0090] The seventeenth PMOS tube M17 and the eighteenth PMOS tube M18 form a current mirror. The current flowing through the seventeenth PMOS tube M17 is equal to the current flowing through the sixteenth NMOS tube, that is, the second reference current IFS. Therefore, the current flowing through the eighteenth PMOS tube M18 is also the second reference current IFS, or the second reference current IFS multiplied by a related coefficient.

[0091] The drain of the eighteenth PMOS transistor M18 serves as the output end of the second current pulling module 30 , is connected to the source of the third PMOS transistor M3 , and outputs the second reference current IFS thereto.

[0092] The drain of the nineteenth NMOS transistor M19 serves as the pull-down end of the second current pulling module 30 , and is connected between the sixth NMOS transistor M6 and the first PMOS transistor M1 , and the pull-down current is the second reference current IFS.

[0093] In order to further improve the matching effect of the current mirror in the secondary slope compensation current generating circuit, reduce the deviation of the drain end of the MOS tube in the current mirror, and ensure the stability of the output current of the secondary slope compensation current generating circuit, the embodiment of the present invention also provides an optional implementation method, please continue to refer to Figure 5 .

[0094] The second current pulling module 30 further includes a twentieth PMOS transistor M20 .

[0095] The source of the twentieth PMOS tube M20 is connected to the drain of the seventeenth PMOS tube M17, the gate of the twentieth PMOS tube M20 is connected to the drain of the twentieth PMOS tube M20, and the drain of the twentieth PMOS tube M20 is connected to the drain of the sixteenth NMOS tube M16.

[0096] Please continue to refer to Figure 3 and Figure 5 Regarding the specific structure of the primary slope compensation current generating module, the embodiment of the present invention also provides an optional implementation.

[0097] The primary slope compensation current generating module 10 includes a first PNP transistor Q1 , a second NPN transistor Q2 , a first resistor R1 and a twenty-first NMOS transistor M21 .

[0098] The base of the first PNP transistor Q1 is used to access the reference voltage (VSLP), the collector of the first PNP transistor Q1 is grounded, and the emitter of the first PNP transistor Q1 is used to connect to the first reference power supply.

[0099] The base of the second NPN transistor Q2 is connected to the emitter of the first PNP transistor Q1 , and the collector of the second NPN transistor Q2 serves as a pull-down terminal of the primary slope compensation current generating module 10 and is connected to the drain of the eleventh PMOS transistor M11 .

[0100] An emitter of the second NPN transistor Q2 is connected to one end of the first resistor R1 , and the other end of the first resistor R1 is grounded.

[0101] The gate of the twenty-first NMOS transistor M21 is used to access the switch signal, the drain of the twenty-first NMOS transistor M21 is connected to the base of the second NPN transistor Q2, and the source of the twenty-first NMOS transistor M21 is grounded.

[0102] It should be understood that the current flowing through the second NPN transistor Q2 is the first reference current I1. The relationship between the first reference current I1 and the duty cycle of the switch signal is as follows: Figure 2 shown.

[0103] An embodiment of the present invention further provides an electronic device, which includes the above-mentioned secondary slope compensation current generating circuit.

[0104] In summary, an embodiment of the present invention provides a secondary slope compensation current generating circuit and an electronic device, wherein the secondary slope compensation current generating circuit comprises: a primary slope compensation current generating module, a first current pulling module, a second current pulling module and a secondary slope compensation current generating module; the primary slope compensation current generating module is connected to the first current pulling module, the first current pulling module is connected to the secondary slope compensation current, and the secondary slope compensation current is also connected to the second current pulling module; the primary slope compensation current generating module is used to generate a corresponding primary slope compensation current according to a received switch signal, so that the first current pulling module pulls a first reference current from the secondary slope compensation current generating module, and the first reference current corresponds to the primary slope compensation current; the second current pulling module is used to provide a second reference current to the secondary slope compensation current generating module; the secondary slope compensation current generating module is used to output a secondary slope compensation current according to the first reference current and the second reference current, and the secondary slope compensation current satisfies a corresponding quadratic term relationship with the primary slope compensation current. The fixed slope ramp current is changed into a quadratic ramp compensation current, so that the slope current compensation has less influence on the maximum peak current of the inductor when the duty cycle is small, thereby improving the transient response and maximum load capacity of the system.

[0105] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0106] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A secondary slope compensation current generating circuit, characterized in that: The secondary slope compensation current generating circuit comprises: a primary slope compensation current generating module, a first current pulling module, a second current pulling module and a secondary slope compensation current generating module; The primary slope compensation current generating module is connected to the first current pulling module, the first current pulling module is connected to the secondary slope compensation current generating module, and the secondary slope compensation current generating module is also connected to the second current pulling module; The primary slope compensation current generating module is used to generate a corresponding primary slope compensation current according to the received switch signal, so that the first current pulling module pulls a first reference current from the secondary slope compensation current generating module, and the first reference current corresponds to the primary slope compensation current; The second current pulling module is used to provide a second reference current to the secondary slope compensation current generating module; The secondary slope compensation current generating module is used to output a secondary slope compensation current according to the first reference current, the second reference current and a feedback current, the secondary slope compensation current satisfies a corresponding quadratic term relationship with the primary slope compensation current, and the feedback current is proportional to the secondary slope compensation current.

2. The secondary slope compensation current generating circuit according to claim 1, characterized in that: The secondary slope compensation current generation module includes a first PMOS tube, a second PMOS tube, a third PMOS tube, a fourth PMOS tube, an output unit and a feedback unit; The source of the second PMOS tube is used to connect to a voltage source, and the drain of the second PMOS tube is connected to the source of the first PMOS tube and the gate of the second PMOS tube; The gate of the first PMOS tube is connected to the drain of the first PMOS tube and the gate of the third PMOS tube, and the drain of the first PMOS tube is connected to the first end of the feedback unit; A connection terminal is led out between the first end of the feedback unit and the first PMOS tube, and is connected to the pull-down end of the first current pulling module and the pull-down end of the second current pulling module; The source of the third PMOS tube is connected to the output end of the second current pulling module, and the drain of the third PMOS tube is grounded; The source of the fourth PMOS tube is used to connect to a voltage source, the gate of the fourth PMOS tube is connected to the source of the third PMOS tube, and the drain of the fourth PMOS tube is connected to the second end of the feedback unit; The first end of the output unit is used to connect to a voltage source, the second end of the output unit is connected to the gate of the fourth PMOS tube, and the third end of the output unit is connected to the output end of the secondary slope compensation current generating module; The output unit is used to output the corresponding secondary slope compensation current following the gate voltage of the fourth PMOS tube; The feedback unit is used to generate a corresponding feedback current according to the current flowing through the fourth PMOS tube, wherein the feedback current is proportional to the current flowing through the fourth PMOS tube, and the current flowing through the fourth PMOS tube is proportional to the secondary slope compensation current.

3. The secondary slope compensation current generating circuit according to claim 2, characterized in that: The feedback unit includes a sixth NMOS tube and a seventh NMOS tube; The drain of the sixth NMOS tube serves as the first end of the feedback unit and is connected to the drain of the first PMOS tube; The gate of the sixth NMOS tube is connected to the gate of the seventh NMOS tube, and the source of the sixth NMOS tube is grounded; The drain of the seventh NMOS tube serves as the second end of the feedback unit and is connected to the drain of the fourth PMOS tube, and the source of the seventh NMOS tube is grounded; And / or, the output unit includes a fifth PMOS tube; The source of the fifth PMOS tube is used to access a voltage source, the gate of the fifth PMOS tube is connected to the gate of the fourth PMOS tube, and the drain of the fifth PMOS tube is connected to the output end of the secondary slope compensation current generating module.

4. The secondary slope compensation current generating circuit according to claim 3, characterized in that: The secondary slope compensation current generating module further includes an eighth NMOS tube and / or a current mirror structure composed of a ninth PMOS tube and a tenth PMOS tube; The drain and gate of the eighth NMOS tube are connected to the drain of the third PMOS tube, and the source of the eighth NMOS tube is grounded; The source of the ninth PMOS tube is connected to the drain of the fourth PMOS tube, the gate of the ninth PMOS tube is connected to the drain of the ninth PMOS tube, and the drain of the ninth PMOS tube is connected to the drain of the seventh NMOS tube; The source of the tenth PMOS tube is connected to the drain of the fifth PMOS tube, the gate of the tenth PMOS tube is connected to the gate of the ninth PMOS tube, and the drain of the tenth PMOS tube serves as the output end of the secondary slope compensation current generating module.

5. The secondary slope compensation current generating circuit according to claim 2, characterized in that: The width-to-length ratio of the first PMOS tube and the width-to-length ratio of the second PMOS tube are 4:1; The width-to-length ratio of the third PMOS tube and the width-to-length ratio of the fourth PMOS tube are 1:

1.

6. The secondary slope compensation current generating circuit according to claim 2, characterized in that: The first current pulling module includes an eleventh PMOS tube, a twelfth PMOS tube, a thirteenth NMOS tube and a fourteenth NMOS tube; The source of the eleventh PMOS tube and the source of the twelfth PMOS tube are used to connect to a voltage source; The gate of the eleventh PMOS tube is connected to the gate of the twelfth PMOS tube and the drain of the eleventh PMOS tube, and the drain of the eleventh PMOS tube is connected to the pull-down end of the primary slope compensation current generating module; The drain of the twelfth PMOS tube is connected to the drain of the thirteenth NMOS tube, the gate of the thirteenth NMOS tube is connected to the gate of the fourteenth NMOS tube, and the source of the thirteenth NMOS tube and the source of the fourteenth NMOS tube are grounded; The drain of the fourteenth NMOS tube serves as the pull-down end of the first current pulling module.

7. The secondary slope compensation current generating circuit according to claim 2, characterized in that: The second current pulling module includes a fifteenth NMOS tube, a sixteenth NMOS tube, a seventeenth PMOS tube, an eighteenth PMOS tube and a nineteenth NMOS tube; The drain of the fifteenth NMOS tube is used to connect to the second reference power supply, the gate of the fifteenth NMOS tube is connected to the gate of the sixteenth NMOS tube and the gate of the nineteenth NMOS tube, and the source of the fifteenth NMOS tube, the source of the sixteenth NMOS tube and the source of the nineteenth NMOS tube are grounded; The drain of the sixteenth NMOS tube is connected to the drain of the seventeenth PMOS tube, the source of the seventeenth PMOS tube and the source of the eighteenth PMOS tube are used to access a voltage source, and the gate of the seventeenth PMOS tube is connected to the drain of the seventeenth PMOS tube and the gate of the eighteenth PMOS tube; The drain of the eighteenth PMOS tube serves as the output end of the second current pulling module; The drain of the nineteenth NMOS tube serves as the pull-down end of the second current pulling module.

8. The secondary slope compensation current generating circuit according to claim 7, characterized in that: The second current pull module also includes a twentieth PMOS tube; The source of the 20th PMOS tube is connected to the drain of the 17th PMOS tube, the gate of the 20th PMOS tube is connected to the drain of the 20th PMOS tube, and the drain of the 20th PMOS tube is connected to the drain of the 16th NMOS tube.

9. The secondary slope compensation current generating circuit according to claim 2, characterized in that: The primary slope compensation current generating module includes a first PNP transistor, a second NPN transistor, a first resistor and a twenty-first NMOS transistor; The base of the first PNP transistor is used to access a reference voltage, the collector of the first PNP transistor is grounded, and the emitter of the first PNP transistor is used to connect to a first reference power supply; The base of the second NPN transistor is connected to the emitter of the first PNP transistor, the collector of the second NPN transistor serves as a pull-down terminal of the primary slope compensation current generating module, the emitter of the second NPN transistor is connected to one end of the first resistor, and the other end of the first resistor is grounded; The gate of the twenty-first NMOS tube is used to access the switch signal, the drain of the twenty-first NMOS tube is connected to the base of the second NPN transistor, and the source of the twenty-first NMOS tube is grounded.

10. An electronic device, characterized in that: The invention comprises the secondary slope compensation current generating circuit according to any one of claims 1 to 9.

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