CN110994951A - Segmented slope compensation circuit and method thereof - Google Patents
Segmented slope compensation circuit and method thereof Download PDFInfo
- Publication number
- CN110994951A CN110994951A CN201911157237.XA CN201911157237A CN110994951A CN 110994951 A CN110994951 A CN 110994951A CN 201911157237 A CN201911157237 A CN 201911157237A CN 110994951 A CN110994951 A CN 110994951A
- Authority
- CN
- China
- Prior art keywords
- current mirror
- circuit
- segmented
- slope compensation
- operational amplifier
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 16
- 230000000875 corresponding effect Effects 0.000 claims description 15
- 230000001276 controlling effect Effects 0.000 claims description 4
- 230000002596 correlated effect Effects 0.000 claims description 2
- 230000004044 response Effects 0.000 abstract description 5
- 230000001052 transient effect Effects 0.000 abstract description 5
- 238000006243 chemical reaction Methods 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 10
- 230000008901 benefit Effects 0.000 description 2
- 230000001939 inductive effect Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000010355 oscillation Effects 0.000 description 2
- HEZMWWAKWCSUCB-PHDIDXHHSA-N (3R,4R)-3,4-dihydroxycyclohexa-1,5-diene-1-carboxylic acid Chemical compound O[C@@H]1C=CC(C(O)=O)=C[C@H]1O HEZMWWAKWCSUCB-PHDIDXHHSA-N 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 210000001503 joint Anatomy 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05F—SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
- G05F1/00—Automatic systems in which deviations of an electric quantity from one or more predetermined values are detected at the output of the system and fed back to a device within the system to restore the detected quantity to its predetermined value or values, i.e. retroactive systems
- G05F1/10—Regulating voltage or current
- G05F1/46—Regulating voltage or current wherein the variable actually regulated by the final control device is dc
- G05F1/56—Regulating voltage or current wherein the variable actually regulated by the final control device is dc using semiconductor devices in series with the load as final control devices
- G05F1/565—Regulating voltage or current wherein the variable actually regulated by the final control device is dc using semiconductor devices in series with the load as final control devices sensing a condition of the system or its load in addition to means responsive to deviations in the output of the system, e.g. current, voltage, power factor
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/0003—Details of control, feedback or regulation circuits
- H02M1/0025—Arrangements for modifying reference values, feedback values or error values in the control loop of a converter
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Automation & Control Theory (AREA)
- Amplifiers (AREA)
Abstract
The invention relates to the technical field of peak current control slope compensation, in particular to a segmented slope compensation circuit and a method thereof. The DC-DC circuit applied to peak current control comprises a reference voltage generating circuit, an operational amplifier circuit and a slope compensation generating circuit; the reference voltage generating circuit is provided with at least two voltage dividing resistors, and a plurality of reference voltage output ends are formed through the voltage dividing resistors; the operational amplifier circuit comprises at least three segmented operational amplifier circuits, the input end of each segmented operational amplifier circuit is connected with the external voltage output end, the comparison end of each segmented operational amplifier circuit is connected with the corresponding reference voltage output end, and the output end of each segmented operational amplifier circuit is connected with the input end of the slope compensation generation circuit. The segmented slope compensation circuit is simple and effective in structure, the conversion efficiency of current control cannot be influenced by over-compensation when the converter works at a small duty ratio, and the stability of transient response characteristics and load carrying capacity of the converter is ensured, so that the reliability of slope compensation is greatly improved, and the stability of a target circuit is improved.
Description
Technical Field
The invention relates to the technical field of peak current control slope compensation, in particular to a segmented slope compensation circuit and a method thereof.
Background
In a DCDC switching power supply, the mode technology has the characteristics of good dynamic characteristic, fast transient response, avoidance of system overcurrent in a fault state, large bandwidth and easiness in implementation and is widely used. However, when the switching converter is introduced into the peak current control mode, the interference resistance is poor, and when the duty ratio is more than 50%, an unstable phenomenon, namely subharmonic oscillation, is generated. It is often necessary to introduce artificial slope compensation to solve this problem.
In the traditional slope compensation mode, sawtooth wave signals with fixed slopes are directly superposed on the sampled inductive current, the slope of the compensation slopes added when the duty ratio is changed in the full range is set to be m, at the moment, one disturbance of the inductive current iL is changed into α × Δ iL0 in the next period, and in order to eliminate the subharmonic oscillation problem, when α is not more than 1,
then, then
That is, as can be seen from the above equation, the slope m of the compensation ramp is 0.5m minimum2. In practical application, the minimum value of the slope of the compensation slope is usually set according to the parameters of the maximum duty ratio, the output voltage, the inductance and the like of the practical application, the slope m of the compensation slope is usually set to be 1.5 to 2 times of the minimum value,
the compensation slope thus designed is necessary for the converter to remain stable when operating at a large duty cycle for stability, but should affect the conversion efficiency of the current control for overcompensation when operating at a smaller duty cycle. Moreover, the slope compensation amount of the circuit at a low duty ratio is obviously overlarge due to the sawtooth wave signal with a fixed slope, and the current feedback capability of the converter is weakened due to the overlarge compensation amount, so that the transient response characteristic and the load carrying capability of the converter are influenced.
Disclosure of Invention
The invention provides a segmented slope compensation circuit and a method thereof, aiming at overcoming the technical problems that the slope compensation quantity is too large in low duty ratio and the current feedback capacity of a converter is weakened due to the excessive compensation quantity, so that the transient response characteristic and the load carrying capacity of the circuit are influenced.
In order to solve the technical problems, the technical scheme of the invention is as follows:
a segmented slope compensation circuit is applied to a peak current control DC-DC circuit and comprises a reference voltage generating circuit, an operational amplifier circuit and a slope compensation generating circuit; the reference voltage generating circuit is provided with at least two voltage dividing resistors, and a plurality of reference voltage output ends are formed by the voltage dividing resistors; the operational amplifier circuit comprises at least three segmented operational amplifier circuits, the input end of each segmented operational amplifier circuit is respectively connected with an external voltage output end, the comparison end of each segmented operational amplifier circuit is respectively connected with the corresponding reference voltage output end, and the output end of each segmented operational amplifier circuit is connected with the input end of the slope compensation generation circuit; the output end of the segmented operational amplifier circuit is switched on and off by comparing an external voltage value with a reference voltage, and the slope compensation generating circuit generates a corresponding slope compensation signal according to the voltage input of the segmented operational amplifier circuit and outputs the corresponding slope compensation signal to the circuit to be compensated.
Further, the reference voltage generating circuit further comprises a first current mirror; a first drain electrode and a grid electrode of the first current mirror are connected with an external bias current output end through a first resistor, and a second drain electrode of the first current mirror is grounded through a divider resistor; and adjacent nodes among the second drain electrode of the first current mirror, the divider resistor and the ground wire are respectively arranged to form a reference voltage output end.
Furthermore, a first NMOS transistor is connected in parallel between the second drain of the first current mirror and the voltage-dividing resistor; and the grid electrode of the first NMOS tube is connected with the second drain electrode, and the source electrode and the drain electrode are grounded.
Furthermore, each segmented operational amplifier circuit comprises a second current mirror, a third current mirror, a load resistor, an input MOS (metal oxide semiconductor) tube and a comparison MOS tube; the grid electrode and the source electrode of the input MOS tube are respectively connected with the external voltage output end and the first drain electrode of the second current mirror; the grid electrode and the source electrode of the comparison MOS tube are respectively connected with the corresponding reference voltage output end and the second drain electrode of the second current mirror; the drain electrodes of the input MOS tube and the comparison MOS tube are respectively connected with the first source electrode and the second source electrode of the third current mirror; the drain electrode of the third current mirror is grounded, and the grid electrode of the third current mirror is connected with the grid electrode of the input MOS tube; and the load resistor is connected between the source electrodes of the input MOS tube and the comparison MOS tube in series.
Furthermore, the specification and the size of the load resistor of each segmented operational amplifier circuit are positively correlated with the size of the reference voltage value received by the segmented operational amplifier circuit.
Further, the slope compensation generating circuit comprises a fourth current mirror and at least three groups of fifth current mirrors; the first drain and the grid of the fifth current mirror are connected with the drain of the comparison MOS tube of the corresponding segmented operational amplifier circuit, the source is grounded, and the second drain is connected with the first drain and the grid of the fourth current mirror; and the slope compensation generation circuit is connected with the external compensation input end through a second drain electrode of a fourth current mirror.
Further, the first current mirror and the second current mirror are both composed of a source current mirror and a drain current mirror; two drains of the source current mirror are respectively butted with two sources of the drain current mirror; the source electrode of the source current mirror is the source electrode of the first current mirror or the second current mirror, and the drain electrode of the drain current mirror is the drain electrode of the first current mirror or the second current mirror.
Further, the source electrodes of the source current mirrors of the first current mirror and the second current mirror and the source electrode of the fourth current mirror are connected with each other; the source electrode current mirror of the first current mirror, the source electrode current mirror of the second current mirror and the grid electrode of the fourth current mirror are connected with an external bias current output end through a first resistor; and the grids of the drain current mirrors of the first current mirror and the second current mirror are connected with an external bias current output end.
Furthermore, the MOS transistors forming the first current mirror, the second current mirror and the fourth current mirror are PMOS transistors, and the MOS transistors forming the third current mirror and the fifth current mirror are NMOS transistors.
The invention also provides a segmented slope compensation method, which is used for performing slope compensation on the peak current control DC-DC circuit and is applied to a segmented slope compensation circuit, wherein the segmented slope compensation circuit comprises a slope compensation generating circuit and at least three segmented operational amplifier circuits; the method comprises the following steps:
acquiring at least three reference voltage values;
controlling a DC-DC circuit according to the peak current to obtain a sawtooth wave voltage output signal;
comparing the sawtooth wave voltage output signal with a reference voltage value, and judging the opening and closing of the output ends of the plurality of segmented operational amplifier circuits;
the input end of the slope compensation generating circuit receives the output voltage of the segmented operational amplifier circuit and generates and outputs a slope compensation signal.
The segmented slope compensation circuit is provided with the plurality of segmented operational amplifier circuits, and the output voltage value of the circuit to be compensated is compared with the reference voltage value in the segmented operational amplifier circuits, so that segmented regulation of the slope compensation signal is realized according to the duty ratio of the circuit to be compensated.
Drawings
Fig. 1 is a block diagram of a segmented slope compensation circuit according to an embodiment of the present invention.
Fig. 2 is a circuit diagram of a reference voltage generating circuit according to an embodiment of the invention.
Fig. 3 is a structural diagram of a panoramic calibration apparatus for a third vehicle according to an embodiment of the present invention.
Fig. 4 is a circuit structure diagram of the segmented operational amplifier circuit according to the embodiment of the present invention.
Fig. 5 is a diagram illustrating an overall circuit structure of the segmented slope compensation circuit according to the embodiment of the present invention.
Fig. 6 is a flow chart illustrating a structure of a segmented slope compensation method according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Examples
Fig. 1 shows a block diagram of the segmented slope compensation circuit of the present embodiment.
As shown in fig. 1, a segmented slope compensation circuit, which is particularly applied to a peak current control DC-DC circuit, includes a reference circuit generating circuit 101, an operational amplifier circuit 102, and a slope compensation generating circuit 103; the reference circuit generating circuit 101 is provided with at least two voltage dividing resistors 202, and the reference circuit generating circuit 101 provides a reference voltage output terminal among an input terminal, the voltage dividing resistors 202, and a ground terminal, thereby generating a plurality of different reference voltages through the voltage dividing resistors 202. Meanwhile, the operational amplifier circuit 102 includes at least three segmented operational amplifier circuits 301, specifically, the number of the voltage dividing resistors 202 and the number of the reference voltage output ends may be determined by the number of the segmented operational amplifier circuits 301, more specifically, the number of the voltage dividing resistors 202 is reduced by one from the number of the segmented operational amplifier circuits 301, and the number of the reference voltage output ends is the same as the number of the segmented operational amplifier circuits 301. The input end of each segmented operational amplifier circuit 301 is connected with the external voltage output end, the comparison end is connected with the corresponding reference voltage output end, the output end is connected with the input end of the slope compensation generating circuit 103, the output end of each segmented operational amplifier circuit 301 is opened and closed by comparing the external voltage value with the reference voltage value, specifically, when the external voltage value is greater than or equal to the reference voltage value, the output end of the segmented operational amplifier circuit 301 is connected, and when the external voltage value is smaller than the reference voltage value, the output end of the segmented operational amplifier circuit 301 is closed. It should be noted that the external voltage output terminal mentioned in this embodiment controls the output voltage of the DC-DC circuit for the peak current to be compensated by the segmented slope compensation circuit. Of course, the voltage output by the external voltage output terminal may specifically be the maximum peak value of the output voltage of the peak current control DC-DC circuit.
In addition, each segmented operational amplifier circuit 301 is switched on and off by comparing an internal external voltage value with a reference voltage value, so that whether the voltage output to the slope compensation generating circuit 103 exists or not is completed, the slope compensation generating circuit 103 generates a corresponding slope compensation signal according to the received voltage and outputs the corresponding slope compensation signal to the circuit to be compensated, so that slope compensation segmented linear change in the circuit to be compensated is completed, and the segmented slope compensation circuit can complete adjustment of the slope compensation signal according to the duty ratio of the circuit to be compensated.
The advantage of this structure lies in, the sectional slope compensation circuit of this embodiment is through setting up a plurality of sectional operational amplifier circuit 301, and through the inside comparison of treating the output voltage value of compensating circuit and reference voltage value of sectional operational amplifier circuit 301, realize realizing the sectional type regulation of slope compensation signal according to the duty cycle of treating the compensating circuit, guarantee that converter work can not influence current control's conversion efficiency because of overcompensation when less duty cycle, guaranteed its transient response characteristic and the stability of on-load ability, thereby greatly increased the reliability of slope compensation, the stability of target circuit has been improved.
Fig. 2 shows a circuit configuration diagram of the reference voltage generating circuit 101 of the present embodiment. In this embodiment, the current mirror is formed by matching and butting the gates of two MOS transistors, and thus the current mirror is formed by two sources and two drains, for clarity, when two sources or two drains of the current mirror need to be described respectively, the current mirror is divided into a first source, a second source, a first drain and a second drain, and certainly, if two sources or two drains do not need to be described respectively, two sources or two drains of the current mirror are referred to by the sources or the drains.
As shown in fig. 2, in some embodiments, the reference voltage generating circuit 101 further includes a first current mirror 201, a first drain and a gate of the first current mirror 201 are connected to the external bias current output terminal through a first resistor, a second drain of the first current mirror 201 is grounded through a voltage-dividing resistor 202, specifically, the voltage-dividing resistors 202 are connected in series, adjacent nodes among the second drain of the first current mirror 201, the voltage-dividing resistor 202 and a ground line are respectively disposed to form a reference voltage output terminal, and each reference voltage output terminal is respectively connected to the comparison terminal of each segmented operational amplifier circuit 301. The reference voltage generating circuit 101 receives an external bias current through the first current mirror 201, forms a constant current in the voltage dividing resistor 202, obtains a plurality of reference voltage values by adjusting the external bias current and the voltage dividing resistor 202, and outputs the reference voltage values to the operational amplifier circuit 102.
In some embodiments, a first NMOS transistor is further connected in parallel between the second drain of the first current mirror 201 and the voltage-dividing resistor 202, a gate of the first NMOS transistor is connected to the second drain, and a source and a drain of the first NMOS transistor are grounded. Specifically, the first NMOS transistor acts as a capacitor in the reference voltage generating circuit 101 to reduce jitter of the reference voltage value output and increase stability of the circuit.
Fig. 3 shows a circuit configuration diagram of the segmented operational amplifier circuit 301 according to the present embodiment.
As shown in fig. 3, in some embodiments, each segmented operational amplifier circuit 301 includes a second current mirror 302, a third current mirror 303, a load resistor R, an input MOS transistor 304, and a comparison MOS transistor 305. The gate of the input MOS transistor 304 is connected to the external voltage output terminal, the source is connected to the first drain of the second current mirror 302, and the drain is connected to the first drain and the gate of the third current mirror 303; the gate of the comparison MOS transistor 305 is connected to the corresponding reference voltage output terminal, the source is connected to the second drain of the second current mirror 302, the drain is connected to the second drain of the third current mirror 303, and the drain of the comparison MOS transistor 305 is connected to the input terminal of the slope compensation generating circuit 103 as the output terminal of the segmented operational amplifier circuit 301. Specifically, the segmented operational amplifier circuit 301 is used as an operational amplifier input geminate transistor by the input MOS transistor 304 and the comparison MOS transistor 305, compares the external voltage value with the reference voltage value, and completes the output of the segmented operational amplifier circuit 301 according to the sizes of the external voltage value and the reference voltage value, so that the structure is simple, and the operation is practical and effective. In addition, the load resistor R is connected in series between the source of the input MOS transistor 304 and the source of the comparison MOS transistor 305, the specification and the resistance value of the load resistor R of each segmented operational amplifier circuit 301 are in positive correlation with the magnitude of the reference voltage value received by the load resistor R, and the control of the magnitude of the output voltage is realized by adjusting the magnitude of the load resistor R by each segmented operational amplifier circuit 301.
Fig. 4 shows a circuit configuration diagram of the slope compensation circuit of the present embodiment.
As shown in fig. 4, in some embodiments, the slope compensation generating circuit 103 includes a fourth current mirror 401 and at least three sets of fifth current mirrors 402, and specifically, the number of the fifth current mirrors 402 matches the number of the segmented operational amplifier circuits 301. A first drain and a gate of each fifth current mirror 402 are respectively connected with the output end of the corresponding segmented operational amplifier circuit 301, and a second drain is connected with a first drain and a gate of the fourth current mirror 401. The second drain of the fourth current mirror 401 is used as the output terminal of the slope compensation generating circuit 103, and is connected to the compensation input terminal of the circuit to be compensated. The slope compensation generating circuit 103 receives the output voltage of the segmented operational amplifier circuit 301 through the fifth current mirror 402, converts the output voltage into a compensation current signal, outputs the compensation current signal to the fourth current mirror 401, collects the compensation current signal through the multiple segmented operational amplifier circuits 301, and obtains a final slope compensation current signal through the fourth current mirror 401.
Referring to fig. 2-3, in some embodiments, the first current mirror 201 and the second current mirror 302 each include a source current mirror and a drain current mirror, and two drains of the source current mirror are respectively connected to two sources of the drain current mirror to form the first current mirror 201 or the second current mirror 302. Specifically, two sources of the source current mirror are used as the sources of the first current mirror 201 or the second current mirror 302, and two drains of the drain current mirror are used as the drains of the first current mirror 201 or the second current mirror 302. The first current mirror 201 and the second current mirror 302 are formed by two sets of current mirrors in a butt joint mode, and therefore the gain of the operational amplifier circuit 102 can be effectively enhanced.
Referring to fig. 2-4, in some embodiments, the source of the source current mirror of the first current mirror 201, the source of the source current mirror of each second current mirror 302, and the source of the fourth current mirror 401 are connected to each other, the source current mirror of the first current mirror 201, the source current mirror of each second current mirror 302, and the gate of the fourth current mirror 401 are all connected to the external bias current output terminal through a first resistor, and the gates of the drain current mirrors of the first current mirror 201 and the second current mirror 302 are connected to the external bias current output terminal. And each current mirror is connected with an external current output end, so that the normal work of each current mirror is realized.
In some embodiments, the MOS transistors forming the first current mirror 201, the second current mirror 302, and the fourth current mirror 401 are PMOS transistors, and the MOS transistors forming the third current mirror 303 and the fifth current mirror 402 are NMOS transistors, and specification parameters of the MOS transistors are determined and adjusted according to requirements of the operational amplifier circuit 102 and the ramp current generating circuit, so as to ensure normal operation of the circuits.
Fig. 5 shows an overall circuit configuration diagram of the segmented slope compensation circuit of the present embodiment. For better operation experience, a specific application scheme of the segmented slope compensation circuit is provided, as shown in fig. 5, specifically, the voltage dividing resistor 202 is provided with two resistors R1 and R2, and the reference voltage output terminal is respectively provided at a node between the second drain of the first current mirror 201 and R1, a node between R1 and R2, and a ground line, which respectively form terminals VH, VM, and GND. The segmented operational amplifier circuit 301 is provided with three operational amplifier circuits, wherein the comparison end of the first segmented operational amplifier circuit is connected with the GND end, the comparison end of the second segmented operational amplifier circuit is connected with the VM end, the comparison end of the third segmented operational amplifier circuit is connected with the VH end, and whether the output end of the three segmented operational amplifier circuits 301 is turned on or not is judged according to the voltage magnitude of the external voltage output end, so that a slope compensation current signal is generated and output through the slope compensation generation circuit 103.
Fig. 6 shows a structural flow chart of the segmented slope compensation method of the present embodiment.
As shown in fig. 6, the present embodiment further provides a segmented slope compensation method, which is applied to a segmented slope compensation circuit for performing slope compensation on a peak current controlled DC-DC circuit, where the compensation method is applied to the segmented slope compensation circuit, and the segmented slope compensation circuit includes a slope compensation generating circuit and at least three segmented operational amplifier circuits; the method comprises the following steps:
601. at least three reference voltage values are obtained.
At least three reference voltage values are obtained through the reference voltage generating circuit, the difference values of the three reference voltage values are uniformly set, and one reference voltage value is 0V, so that the output of the basic slope compensation current is ensured.
602. And controlling the DC-DC circuit according to the peak current to obtain a sawtooth wave voltage output signal.
The output voltage of the DC-DC circuit is controlled by receiving the peak current, so that the duty ratio of the output voltage is judged, and the output voltage which can represent the duty ratio of the output voltage is obtained.
603. And comparing the sawtooth wave voltage output signal with a reference voltage value, and judging the opening and closing of the output ends of the plurality of segmented operational amplifier circuits.
And comparing the reference voltage value through the received sawtooth wave voltage output signal so as to judge and decide the opening and closing of the output end of the segmented operational amplifier circuit. Here, the duty interval to be compensated may be controlled by controlling the magnitude of the reference voltage value.
604. The input end of the slope compensation generating circuit receives the output voltage of the segmented operational amplifier circuit and generates and outputs a slope compensation signal.
The output voltages of the segmented operational amplifier circuits are collected to the input end of the slope compensation generating circuit, the slope compensation generating circuit converts the output voltages according to the received output voltages, generates slope compensation current and outputs the slope compensation current to the circuit to be compensated.
The segmented slope compensation method is simple and effective, and can avoid the phenomenon of over-compensation easily occurring when the duty ratio of the peak current control circuit is low, so that under the condition that the duty ratio of the converter is changed, a proper compensation amount is generated, and the stability and the reliability of the circuit to be compensated are effectively improved.
It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.
Claims (10)
1. A segmented slope compensation circuit is applied to a peak current control DC-DC circuit and is characterized by comprising a reference voltage generating circuit (101), an operational amplifier circuit (102) and a slope compensation generating circuit (103); the reference voltage generating circuit (101) is provided with at least two voltage dividing resistors (202), and a plurality of reference voltage output ends are formed by the voltage dividing resistors (202); the operational amplifier circuit (102) comprises at least three segmented operational amplifier circuits (301), the input end of each segmented operational amplifier circuit (301) is respectively connected with an external voltage output end, the comparison end is respectively connected with the corresponding reference voltage output end, and the output end is connected with the input end of the slope compensation generation circuit (103); the output end of the segmented operational amplifier circuit (301) is switched on and off through comparison of an external voltage value and a reference voltage, and the slope compensation generating circuit (103) generates a corresponding slope compensation signal according to the voltage input of the segmented operational amplifier circuit (301) and outputs the corresponding slope compensation signal to a circuit to be compensated.
2. The segmented slope compensation circuit of claim 1, wherein the reference voltage generation circuit (101) further comprises a first current mirror (201); a first drain and a gate of the first current mirror (201) are connected with an external bias current output end through a first resistor, and a second drain of the first current mirror (201) is grounded through a voltage dividing resistor (202); and adjacent nodes among the second drain of the first current mirror (201), the voltage dividing resistor (202) and the ground wire are respectively arranged to form a reference voltage output end.
3. The segmented slope compensation circuit according to claim 2, wherein a first NMOS transistor is further connected in parallel between the second drain of the first current mirror (201) and the voltage dividing resistor (202); and the grid electrode of the first NMOS tube is connected with the second drain electrode, and the source electrode and the drain electrode are grounded.
4. The segmented slope compensation circuit according to claim 2 or 3, wherein each segmented operational amplifier circuit (301) comprises a second current mirror (302), a third current mirror (302), a load resistor, an input MOS transistor (304) and a comparison MOS transistor (305); the grid electrode and the source electrode of the input MOS tube (304) are respectively connected with the external voltage output end and the first drain electrode of the second current mirror (302); the grid electrode and the source electrode of the comparison MOS tube (305) are respectively connected with the corresponding reference voltage output end and the second drain electrode of the second current mirror (302); the drains of the input MOS tube (304) and the comparison MOS tube (305) are respectively connected with the first source and the second source of the third current mirror (302); the drain electrode of the third current mirror (302) is grounded, and the grid electrode of the third current mirror is connected with the grid electrode of the input MOS tube (304); the load resistor is connected in series between the source electrodes of the input MOS tube (304) and the comparison MOS tube (305).
5. The segmented slope compensation circuit according to claim 4, wherein the size and magnitude of the load resistor of each segmented operational amplifier circuit (301) is positively correlated with the magnitude of the reference voltage value received by the segmented operational amplifier circuit.
6. The segmented slope compensation circuit according to claim 4, wherein the slope compensation generating circuit (103) comprises a fourth current mirror (401) and at least three sets of fifth current mirrors (402); a first drain and a gate of the fifth current mirror (402) are connected with the drain of the comparison MOS tube (305) of the corresponding segmented operational amplifier circuit (301), a source is grounded, and a second drain is connected with the first drain and the gate of the fourth current mirror (401); the slope compensation generation circuit (103) is connected with the external compensation input end through a second drain electrode of a fourth current mirror (401).
7. The segmented slope compensation circuit of claim 6, wherein the first current mirror (201) and the second current mirror (302) are each comprised of a source current mirror and a drain current mirror; two drains of the source current mirror are respectively butted with two sources of the drain current mirror; the source electrode of the source current mirror is the source electrode of the first current mirror (201) or the second current mirror (302), and the drain electrode of the drain current mirror is the drain electrode of the first current mirror (201) or the second current mirror (302).
8. The segmented slope compensation circuit according to claim 7, wherein the source of the source current mirror of the first current mirror (201), the second current mirror (302) and the source of the fourth current mirror (401) are connected to each other; the source electrode current mirror of the first current mirror (201), the source electrode current mirror of the second current mirror (302) and the grid electrode of the fourth current mirror (401) are all connected with an external bias current output end through a first resistor; the gates of the drain current mirrors of the first current mirror (201) and the second current mirror (302) are connected to an external bias current output.
9. The segmented slope compensation circuit according to claim 8, wherein the MOS transistors constituting the first current mirror (201), the second current mirror (302) and the fourth current mirror (401) are PMOS transistors, and the MOS transistors constituting the third current mirror (302) and the fifth current mirror (402) are NMOS transistors.
10. A segmented slope compensation method is used for slope compensation of a peak current control DC-DC circuit, and is characterized in that the compensation method is applied to a segmented slope compensation circuit which comprises a slope compensation generation circuit and at least three segmented operational amplifier circuits; the method comprises the following steps:
acquiring at least three reference voltage values;
controlling a DC-DC circuit according to the peak current to obtain a sawtooth wave voltage output signal;
comparing the sawtooth wave voltage output signal with a reference voltage value, and judging the opening and closing of the output ends of the plurality of segmented operational amplifier circuits;
the input end of the slope compensation generating circuit receives the output voltage of the segmented operational amplifier circuit and generates and outputs a slope compensation signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911157237.XA CN110994951A (en) | 2019-11-22 | 2019-11-22 | Segmented slope compensation circuit and method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911157237.XA CN110994951A (en) | 2019-11-22 | 2019-11-22 | Segmented slope compensation circuit and method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110994951A true CN110994951A (en) | 2020-04-10 |
Family
ID=70085987
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911157237.XA Pending CN110994951A (en) | 2019-11-22 | 2019-11-22 | Segmented slope compensation circuit and method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110994951A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112631366A (en) * | 2020-11-26 | 2021-04-09 | 玄武石半导体(武汉)有限公司 | Control circuit and control method for continuous piecewise linear current |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011091888A (en) * | 2009-10-20 | 2011-05-06 | Sharp Corp | Switching control circuit and switching power supply device using the same |
| CN102324843A (en) * | 2011-05-17 | 2012-01-18 | 浙江大学 | High-precision sectional type linear slope compensation circuit |
| US9444338B1 (en) * | 2013-03-15 | 2016-09-13 | Maxim Integrated Products, Inc. | Systems and methods to calibrate switching regulators |
| CN108599566A (en) * | 2018-05-08 | 2018-09-28 | 电子科技大学 | A kind of buck DC-DC converter self-adaptable slop compensation circuit |
| CN211089432U (en) * | 2019-11-22 | 2020-07-24 | 深圳市德赛微电子技术有限公司 | Sectional slope compensation circuit |
-
2019
- 2019-11-22 CN CN201911157237.XA patent/CN110994951A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011091888A (en) * | 2009-10-20 | 2011-05-06 | Sharp Corp | Switching control circuit and switching power supply device using the same |
| CN102324843A (en) * | 2011-05-17 | 2012-01-18 | 浙江大学 | High-precision sectional type linear slope compensation circuit |
| US9444338B1 (en) * | 2013-03-15 | 2016-09-13 | Maxim Integrated Products, Inc. | Systems and methods to calibrate switching regulators |
| CN108599566A (en) * | 2018-05-08 | 2018-09-28 | 电子科技大学 | A kind of buck DC-DC converter self-adaptable slop compensation circuit |
| CN211089432U (en) * | 2019-11-22 | 2020-07-24 | 深圳市德赛微电子技术有限公司 | Sectional slope compensation circuit |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112631366A (en) * | 2020-11-26 | 2021-04-09 | 玄武石半导体(武汉)有限公司 | Control circuit and control method for continuous piecewise linear current |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI406489B (en) | Dc-dc converter and method | |
| US9774255B2 (en) | Synchronous buck DC-DC converter and method thereof | |
| US11848609B2 (en) | Control circuit and method for switching power converters | |
| CN101728822B (en) | Current limiting load switch with dynamically generated tracking reference voltage | |
| US20090115388A1 (en) | DC/DC converter | |
| US6885177B2 (en) | Switching regulator and slope correcting circuit | |
| KR20010060367A (en) | Band-gap reference circuit | |
| US20130278239A1 (en) | Precharge circuits and methods for dc-dc boost converters | |
| CN111869072A (en) | Control circuit of voltage conversion circuit | |
| CN108900069B (en) | Self-adaptive secondary slope compensation circuit based on duty ratio | |
| US7508174B2 (en) | Anti-ringing switching regulator and control method therefor | |
| US20190393786A1 (en) | Two-stage multi-phase switching power supply with ramp generator dc offset for enhanced transient response | |
| US9231470B2 (en) | Control circuit, time calculating unit, and operating method for control circuit | |
| CN211089432U (en) | Sectional slope compensation circuit | |
| CN108900082B (en) | Switching power supply conversion system | |
| CN112886823B (en) | Primary side control circuit, control method and isolated switching power supply | |
| CN110994951A (en) | Segmented slope compensation circuit and method thereof | |
| KR100279294B1 (en) | Source follower circuit having improved gain and output circuit of solid-state imaging device using the same | |
| CN113014216B (en) | Operational amplifier | |
| TWI847203B (en) | Power limiting circuit | |
| CN218124554U (en) | Frequency compensation circuit applied to step-down DC-DC converter | |
| CN219875468U (en) | Self-adaptive delay compensation current comparison circuit and switching power supply circuit | |
| US11955880B2 (en) | Overcurrent protection circuit, power supply control device, inverting type switching power supply | |
| CN111525782B (en) | Drive control method and circuit of power tube | |
| US11239758B2 (en) | Power supply system with stable loop |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |