A single-inductor three-output switching converter current ripple control system and method
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SOUTHWEST UNIVERSITY FOR NATIONALITIES
- Filing Date
- 2023-03-14
- Publication Date
- 2026-07-03
Smart Images
Figure CN116317502B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of switching converter technology, and specifically to a current ripple control system and method for a single-inductor three-output switching converter. Background Technology
[0002] With the widespread use of portable electronic products such as smartphones and tablets, users have increasingly higher requirements for the size, cost, and efficiency of their power supplies. A single-inductor three-output switching converter can provide three independent power supplies for portable electronic products, LED lighting, etc., reducing the number of inductors and control chips, thereby effectively reducing power supply size, lowering manufacturing costs, and improving conversion efficiency.
[0003] Traditional voltage control works by comparing the detected output voltage with a reference voltage using a voltage loop. The resulting error signal is compensated by an error amplifier and then compared with a sawtooth wave. The comparison result is used to control the switching transistor's on / off state, thereby regulating the output voltage of the switching converter. This method, used in single-inductor three-output converters, suffers from drawbacks such as severe crosstalk between output branches and slow transient response to load changes. Summary of the Invention
[0004] To address the problems existing in the prior art, the purpose of this invention is to provide a current ripple control system and method for a single-inductor three-output switching converter, which has better load transient performance and smaller output crossover effect, and is applicable to various topologies of single-inductor three-output switching converters.
[0005] The technical solution adopted in this invention is as follows:
[0006] A current ripple control system for a single-inductor three-output switching converter includes: a converter TD and control devices corresponding to switching transistors S1, S2, and S3, wherein the converter TD is electrically connected to the control devices corresponding to switching transistors S1, S2, and S3; the control devices include an inductor current ripple controller CTR1, an output current ripple controller CTR2, and a CTR3, wherein the inductor current ripple controller CTR1, the output current ripple controller CTR2, and the CTR3 are electrically connected to each other.
[0007] Preferably, the inductor current ripple controller CTR1 includes: an inductor current detection circuit, a voltage detection circuit VS1, an error amplifier EAP1, a comparator CMP1, an RS flip-flop TGR1, a drive circuit DR1, and a reference voltage V. ref1 The voltage detection circuit VS1, error amplifier EAP1, comparator CMP1, RS flip-flop TGR1, and drive circuit DR1 are sequentially electrically connected. The inductor current detection circuit is electrically connected to comparator CMP1. The reference voltage V... ref1Electrically connected to error amplifier EAP1, the RS flip-flop TGR1 is also connected to clock signal CLK; the output current ripple controller CTR2 includes: a b-channel output current detection circuit, a voltage detection circuit VS2, error amplifier EAP2, comparator CMP2, RS flip-flop TGR2, and drive circuit DR2, and reference voltage V. ref2 The b-channel output current detection circuit is electrically connected to comparator CMP2, and the reference voltage V ref2 Electrically connected to error amplifier EAP2, the RS flip-flop TGR2 is also connected to clock signal CLK; the output current ripple controller CTR3 includes: a c-channel output current detection circuit, a voltage detection circuit VS3, error amplifier EAP3, comparator CMP3, RS flip-flop TGR3, and drive circuit DR3, and reference voltage V. ref3 The c-channel output current detection circuit is electrically connected to comparator CMP3, and the reference voltage V ref3 The RS flip-flop TGR3 is electrically connected to the error amplifier EAP3 and is also connected to the clock signal CLK. The voltage detection circuits VS1, VS2, and VS3, the drive circuits DR1, DR2, and DR3 are respectively connected to the corresponding single-inductor three-output switching converters.
[0008] Furthermore, the inductor current detection circuit includes: an inductor current detection circuit IS1 and a ramp signal I. c1 Adder ADD1, inductor current detection circuit IS1, and ramp signal I c1 Each is electrically connected to adder ADD1, which is electrically connected to comparator CMP1; the b-channel output current detection circuit includes: output current detection circuit IS2, ramp signal I... c2 Adder ADD2, output current detection circuit IS2, and ramp signal I c2 Each is electrically connected to adder ADD2, which is electrically connected to comparator CMP2; the c-channel output current detection circuit includes: output current detection circuit IS3, ramp signal I... c3 Adder ADD3, output current detection circuit IS3, and ramp signal I c3 Each is electrically connected to adder ADD3, which is electrically connected to comparator CMP3; the inductor current detection circuit IS1, output current detection circuit IS2, and output current detection circuit IS3 are respectively connected to the corresponding single-inductor three-output switching converter.
[0009] Furthermore, the converter TD is a Buck converter.
[0010] Furthermore, the converter TD is a Boost converter.
[0011] Furthermore, the converter TD is a Buck-Boost converter.
[0012] A current ripple control method for a single-inductor three-output switching converter, the control flow is as follows:
[0013] S1: The inductor current ripple controller CTR1 detects the output voltage V of the single-inductor three-output switching converter. oa The inductor current detection circuit detects the inductor current I. L The output current ripple controller CTR2 detects the output voltage V of the single-inductor three-output switching converter. ob The output current detection circuit detects the output current I. ob The CTR3 output current ripple controller detects the output voltage V of the single-inductor three-output switching converter. oc The output current detection circuit detects the output current I. oc ;
[0014] S2: Output voltage V oa and reference voltage V ref1 The error signal V is amplified by the error amplifier EAP1. e1 The current I fed into the positive input terminal of comparator CMP1 is the inductor current. L and ramp signal I c1 The inductor current I after compensation is obtained through adder ADD1. Lc The voltage is fed into the negative input terminal of comparator CMP1; the output voltage V ob and reference voltage V ref2 The error signal V is amplified by error amplifier EAP2. e2 The current I is fed into the positive input terminal of comparator CMP2, and the output current is... ob and ramp signal I c2 The output current I after compensation is obtained through adder ADD2 bc The voltage is fed into the negative input terminal of comparator CMP2; the output voltage V oc and reference voltage V ref3 The error signal V is amplified by error amplifier EAP3. e3 The current I is fed into the positive input terminal of comparator CMP3, and the output current is... oc and ramp signal I c3 The output current I after compensation is obtained through adder ADD3 cc The signal is fed into the negative input terminal of comparator CMP3;
[0015] S3: I Lc and V e1 The comparison result is sent to the S terminal of RS flip-flop TGR1; I bc and Ve2 The comparison result is sent to the S terminal of RS flip-flop TGR2; I cc and V e3 The comparison result is sent to the S terminal of RS flip-flop TGR3;
[0016] S4: Clock signal CLK is sent to the R terminal of RS flip-flop TGR1; clock signal CLK is sent to the R terminal of RS flip-flop TGR2; clock signal CLK is sent to the R terminal of RS flip-flop TGR3;
[0017] S5: The Q output signal of RS flip-flop TGR1 is used to obtain the control signal of switch S1, which controls the turn-on and turn-off of switch S1 in switch converter TD via drive circuit DR1; the output signal of RS flip-flop TGR2 is used to obtain the control signal of switch S2, which controls the turn-on and turn-off of switch S2 in switch converter TD via drive circuit DR2; the Q output signal of RS flip-flop TGR3 is used to obtain the control signal of switch S3, which controls the turn-on and turn-off of switch S3 in switch converter TD via drive circuit DR3.
[0018] In summary, the present invention has the following beneficial technical effects:
[0019] 1. When the load of the single-inductor three-output switching converter changes, the present invention can quickly adjust the control pulse of the switching transistor, resulting in a short output voltage adjustment time and good load transient performance of the converter.
[0020] 2. When the load of the output branch of the single-inductor three-output switching converter changes, the present invention can effectively reduce the cross-influence between the output branches, resulting in good system stability. Attached Figure Description
[0021] The present invention will be described by way of example and with reference to the accompanying drawings, wherein:
[0022] Figure 1 This is a schematic diagram of the overall topology of the present invention;
[0023] Figure 2 This is a schematic diagram of the overall topology of Embodiment 1 of the present invention;
[0024] Figure 3 This is a timing diagram of the device of the present invention, including waveforms of inductor current and control pulses of switching devices;
[0025] Figure 4 The transient response waveform of a traditional voltage-controlled single-inductor three-output Buck converter when the load on output branch a changes.
[0026] Figure 5This is a transient response waveform diagram of the voltage-controlled single-inductor three-output Buck converter according to Embodiment 1 of the present invention when the load on output branch a changes.
[0027] Figure 6 The transient response waveform of a traditional voltage-controlled single-inductor three-output Buck converter when the load on output branch b changes.
[0028] Figure 7 This is a transient response waveform diagram of the voltage-controlled single-inductor three-output Buck converter according to Embodiment 1 of the present invention when the load on output branch b changes.
[0029] Figure 8 The transient response waveform of a traditional voltage-controlled single-inductor three-output Buck converter when the load on the output branch c changes.
[0030] Figure 9 This is a transient response waveform diagram of the voltage-controlled single-inductor three-output Buck converter according to Embodiment 1 of the present invention when the load on the output branch c changes. Detailed Implementation
[0031] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.
[0032] In the description of the embodiments of this application, it should be noted that the terms "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0033] The following is combined Figures 1-9 The present invention will be described in detail below.
[0034] Example 1
[0035] A current ripple control system for a single-inductor three-output switching converter includes: a converter TD and control devices corresponding to switching transistors S1, S2, and S3, wherein the converter TD is electrically connected to the control devices corresponding to switching transistors S1, S2, and S3; the control devices include an inductor current ripple controller CTR1, an output current ripple controller CTR2, and a CTR3, wherein the inductor current ripple controller CTR1, the output current ripple controller CTR2, and the CTR3 are electrically connected to each other.
[0036] The inductor current ripple controller CTR1 includes: an inductor current detection circuit, a voltage detection circuit VS1, an error amplifier EAP1, a comparator CMP1, an RS flip-flop TGR1, a drive circuit DR1, and a reference voltage V. ref1 The voltage detection circuit VS1, error amplifier EAP1, comparator CMP1, RS flip-flop TGR1, and drive circuit DR1 are sequentially electrically connected. The inductor current detection circuit is electrically connected to comparator CMP1. The reference voltage V... ref1 Electrically connected to error amplifier EAP1, the RS flip-flop TGR1 is also connected to clock signal CLK; the output current ripple controller CTR2 includes: a b-channel output current detection circuit, a voltage detection circuit VS2, error amplifier EAP2, comparator CMP2, RS flip-flop TGR2, and drive circuit DR2, and reference voltage V. ref2 The b-channel output current detection circuit is electrically connected to comparator CMP2, and the reference voltage V ref2 Electrically connected to error amplifier EAP2, the RS flip-flop TGR2 is also connected to clock signal CLK; the output current ripple controller CTR3 includes: a c-channel output current detection circuit, a voltage detection circuit VS3, error amplifier EAP3, comparator CMP3, RS flip-flop TGR3, and drive circuit DR3, and reference voltage V. ref3 The c-channel output current detection circuit is electrically connected to comparator CMP3, and the reference voltage V ref3 The RS flip-flop TGR3 is electrically connected to the error amplifier EAP3 and is also connected to the clock signal CLK. The voltage detection circuits VS1, VS2, and VS3, the drive circuits DR1, DR2, and DR3 are respectively connected to the corresponding single-inductor three-output switching converters.
[0037] The inductor current detection circuit includes: inductor current detection circuit IS1, and ramp signal I. c1 Adder ADD1, inductor current detection circuit IS1, and ramp signal I c1Each is electrically connected to adder ADD1, which is electrically connected to comparator CMP1; the b-channel output current detection circuit includes: output current detection circuit IS2, ramp signal I... c2 Adder ADD2, output current detection circuit IS2, and ramp signal I c2 Each is electrically connected to adder ADD2, which is electrically connected to comparator CMP2; the c-channel output current detection circuit includes: output current detection circuit IS3, ramp signal I... c3 Adder ADD3, output current detection circuit IS3, and ramp signal I c3 Each is electrically connected to adder ADD3, which is electrically connected to comparator CMP3; the inductor current detection circuit IS1, output current detection circuit IS2, and output current detection circuit IS3 are respectively connected to the corresponding single-inductor three-output switching converter.
[0038] The control flow is as follows:
[0039] S1: The inductor current ripple controller CTR1 detects the output voltage V of the single-inductor three-output switching converter. oa The inductor current detection circuit detects the inductor current I. L The output current ripple controller CTR2 detects the output voltage V of the single-inductor three-output switching converter. ob The output current detection circuit detects the output current I. ob The CTR3 output current ripple controller detects the output voltage V of the single-inductor three-output switching converter. oc The output current detection circuit detects the output current I. oc ;
[0040] S2: Output voltage V oa and reference voltage V ref1 The error signal V is amplified by the error amplifier EAP1. e1 The current I fed into the positive input terminal of comparator CMP1 is the inductor current. L and ramp signal I c1 The inductor current I after compensation is obtained through adder ADD1. Lc The voltage is fed into the negative input terminal of comparator CMP1; the output voltage V ob and reference voltage V ref2 The error signal V is amplified by error amplifier EAP2. e2 The current I is fed into the positive input terminal of comparator CMP2, and the output current is... ob and ramp signal I c2 The output current I after compensation is obtained through adder ADD2 bc The voltage is fed into the negative input terminal of comparator CMP2; the output voltage Voc and reference voltage V ref3 The error signal V is amplified by error amplifier EAP3. e3 The current I is fed into the positive input terminal of comparator CMP3, and the output current is... oc and ramp signal I c3 The output current I after compensation is obtained through adder ADD3 cc The signal is fed into the negative input terminal of comparator CMP3;
[0041] S3: I Lc and V e1 The comparison result is sent to the S terminal of RS flip-flop TGR1; I bc and V e2 The comparison result is sent to the S terminal of RS flip-flop TGR2; I cc and V e3 The comparison result is sent to the S terminal of RS flip-flop TGR3;
[0042] S4: Clock signal CLK is sent to the R terminal of RS flip-flop TGR1; clock signal CLK is sent to the R terminal of RS flip-flop TGR2; clock signal CLK is sent to the R terminal of RS flip-flop TGR3;
[0043] S5: The Q output signal of RS flip-flop TGR1 is used to obtain the control signal of switch S1, which controls the turn-on and turn-off of switch S1 in switch converter TD via drive circuit DR1; the output signal of RS flip-flop TGR2 is used to obtain the control signal of switch S2, which controls the turn-on and turn-off of switch S2 in switch converter TD via drive circuit DR2; the Q output signal of RS flip-flop TGR3 is used to obtain the control signal of switch S3, which controls the turn-on and turn-off of switch S3 in switch converter TD via drive circuit DR3.
[0044] Figure 2 As shown, at the start of any cycle, the clock signal CLK resets RS flip-flops TGR1, TGR2, and TGR3. The Q signals of RS flip-flops TGR1, TGR2, and TGR3 control the turn-off of the main switch S1 and branch switches S2 and S3 respectively through drive circuits DR1, DR2, and DR3. The control circuit is divided into an inductor current ripple control circuit, a b-channel output current ripple control circuit, and a c-channel output current ripple control circuit; the inductor current ripple control circuit samples the a-channel output voltage V. oa and the compensated inductor current I Lc Output voltage V oa With reference voltage V ref1 The comparison result is passed through error amplifier EAP1 to obtain the reference current V. e1 Inductor current I L and ramp signal I c1The compensated inductor current I is obtained through adder ADD1. Lc ;I Lc With V e1 The input signal at the S terminal of RS flip-flop TGR1 is obtained by comparator CMP1, generating the turn-on signal for the main switch S1, which is connected to the input terminal of drive circuit DR1. The output terminal of DR1 is connected to the gate control terminal of the main switch S1, controlling the conduction of switch S1. The b-channel output current ripple control circuit samples the b-channel output voltage V. ob and the compensated output current I c2 Output voltage V ob and reference voltage V ref2 The error signal V is amplified by error amplifier EAP2. e2 The current I is fed into the positive input terminal of comparator CMP2, and the output current is... ob and ramp signal I c2 The compensated output current Ibc, obtained after passing through adder ADD2, is fed into the negative input terminal of comparator CMP2; bc and V e2 The comparison result is sent to the S terminal of RS flip-flop TGR2, controlling the conduction of branch switch S2. The c-channel output current ripple control circuit samples the c-channel output voltage V. oc and the compensated output current I c3 Output voltage V oc and reference voltage V ref3 The error signal V is amplified by error amplifier EAP3. e3 The current I is fed into the positive input terminal of comparator CMP3, and the output current is... oc and ramp signal I c3 The output current I after compensation is obtained through adder ADD3 cc The input is fed into the negative input terminal of comparator CMP3; I cc and V e3 The comparison result is sent to the S terminal of RS flip-flop TGR3 to control the conduction of branch switch S3.
[0045] Figure 3 The diagram shown is a timing diagram of the device of the present invention. At the beginning of each switching cycle, the clock signal CLK resets flip-flops TGR1, TGR2, and TGR3, and the control signal V... gs1 V gs2 and V gs3 When the voltage level is low, switches S1, S2, and S3 are turned off, and the inductor current I... L Output current I ob and I oc Linear decrease; when the output current I ob Drop to reference current V e2 When the switching transistor S2 is turned on, the output current I...ob It begins to rise linearly; when the output current I... oc Drop to reference current V e3 When the switching transistor S3 is turned on, the output current I... oc It begins to rise linearly; when the inductor current I... L Drop to reference current V e1 When the switching transistor S1 is turned on, the inductor current I... L It begins to rise linearly; until the next clock signal arrives, the circuit enters the next switching cycle.
[0046] The method of this invention was simulated and analyzed in the time domain using PSIM simulation software, and the results are as follows.
[0047] Figures 4 to 9 The time-domain simulation waveforms of the output voltage and output current of a single-inductor three-output Buck converter using voltage control and the present invention, when the load on the output branch changes abruptly. Figure 4 , Figure 5 The time-domain simulation waveforms of the output voltage and output current in the output branch a of the single-inductor three-output Buck converter, corresponding to voltage control and current ripple control respectively, are shown. Figure 6 , Figure 7 The time-domain simulation waveforms of the output voltage and output current of the output branch b of the single-inductor three-output Buck converter, corresponding to voltage control and current ripple control respectively, are shown. Figure 8 , Figure 9 The time-domain simulation waveforms of the output voltage and output current of the output branch c of the single-inductor three-output Buck converter, corresponding to voltage control and current ripple control respectively, are shown. Figure 4 , Figure 5 In the above, the output current I of output branch a of voltage-controlled single-inductor three-output Buck converter and current-ripple-controlled single-inductor three-output Buck converter is shown. oa The output current I of output branch b changes abruptly from 1A to 1.5A. ob and the output current I of the output branch c oc When each is 1A, the output voltage V of the output branch a of the voltage-controlled single-inductor three-output Buck converter is... oa After approximately 5ms, it enters a new steady state. The cross-effect of output branch a on output branch b is 339mV, and the cross-effect of output branch a on output branch c is 337mV. In contrast, the adjustment time for the single-inductor three-output Buck switch converter based on current ripple control of this invention to enter a new steady state is approximately 3ms. The cross-effect of output branch a on output branch b is 270mV, and the cross-effect of output branch a on output branch c is 260mV. Figure 6 , Figure 7In the voltage-controlled single-inductor three-output Buck converter and the single-inductor three-output Buck converter based on current ripple control, the output current I of output branch b is... ob The output current I of output branch a changes abruptly from 1A to 1.5A. oa and the output current I of the output branch c oc When each is 1A, the output voltage V of the output branch b of the voltage-controlled single-inductor three-output Buck converter is... ob After approximately 2ms, it enters a new steady state. The cross-effect of output branch b on output branch a is 1V, and the cross-effect of output branch b on output branch c is 330mV. In contrast, the adjustment time for the single-inductor three-output Buck switch converter based on current ripple control of this invention to enter a new steady state is approximately 1ms, and the cross-effect of output branch b on output branch a is 760mV, while the cross-effect of output branch b on output branch c is 280mV. Figure 8 , Figure 9 In the above, the output current I of the output branch c of the voltage-controlled single-inductor three-output Buck converter and the single-inductor three-output Buck converter based on current ripple control is... oc The output current I of output branch a changes abruptly from 1A to 1.5A. oa and the output current I of output branch b ob When each is 1A, the output voltage V of the output branch c of the voltage-controlled single-inductor three-output Buck converter is... oc After approximately 1.8 ms, the converter enters a new steady state. The cross-influence of output branch c on output branch a is 1V, and the cross-influence of output branch c on output branch b is 300mV. In contrast, the adjustment time for the single-inductor three-output Buck converter based on current ripple control of this invention to enter a new steady state is approximately 1 ms, the cross-influence of output branch c on output branch a is 740mV, and the cross-influence of output branch c on output branch b is 200mV. It can be seen that the switching converter of this invention has a short transient settling time, good load transient performance, and minimal cross-influence between output branches.
[0048] The embodiments described above merely illustrate specific implementation methods of this application, and while the descriptions are detailed and specific, they should not be construed as limiting the scope of protection of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the technical solution of this application, and these modifications and improvements all fall within the scope of protection of this application.
Claims
1. A current ripple control system for a single-inductor three-output switching converter, characterized in that, include: The converter TD and the control devices corresponding to the switching transistors S1, S2, and S3 are electrically connected. The control devices include an inductor current ripple controller CTR1, an output current ripple controller CTR2, and a CTR3, which are electrically connected to each other. The inductor current ripple controller CTR1 includes: an inductor current detection circuit, a voltage detection circuit VS1, an error amplifier EAP1, a comparator CMP1, an RS flip-flop TGR1, a drive circuit DR1, and a reference voltage V. ref1 The voltage detection circuit VS1, error amplifier EAP1, comparator CMP1, RS flip-flop TGR1, and drive circuit DR1 are sequentially electrically connected. The inductor current detection circuit is electrically connected to comparator CMP1. The reference voltage V... ref1 Electrically connected to error amplifier EAP1, the RS flip-flop TGR1 is also connected to clock signal CLK; the output current ripple controller CTR2 includes: a b-channel output current detection circuit, a voltage detection circuit VS2, error amplifier EAP2, comparator CMP2, RS flip-flop TGR2, and drive circuit DR2, and reference voltage V. ref2 The b-channel output current detection circuit is electrically connected to comparator CMP2, and the reference voltage V ref2 Electrically connected to error amplifier EAP2, the RS flip-flop TGR2 is also connected to clock signal CLK; the output current ripple controller CTR3 includes: a c-channel output current detection circuit, a voltage detection circuit VS3, error amplifier EAP3, comparator CMP3, RS flip-flop TGR3, and drive circuit DR3, and reference voltage V. ref3 The c-channel output current detection circuit is electrically connected to comparator CMP3, and the reference voltage V ref3 The RS flip-flop TGR3 is electrically connected to the error amplifier EAP3 and is also connected to the clock signal CLK; the voltage detection circuits VS1, VS2, and VS3, the drive circuits DR1, DR2, and DR3 are respectively connected to the corresponding single-inductor three-output switching converters. The inductor current detection circuit includes: an inductor current detection circuit IS1 and a ramp signal I. c1 Adder ADD1, inductor current detection circuit IS1, and ramp signal I c1 Each is electrically connected to adder ADD1, which is electrically connected to comparator CMP1; the b-channel output current detection circuit includes: output current detection circuit IS2, ramp signal I... c2 Adder ADD2, output current detection circuit IS2, and ramp signal I c2 Each is electrically connected to adder ADD2, which is electrically connected to comparator CMP2; the c-channel output current detection circuit includes: output current detection circuit IS3, ramp signal I... c3 Adder ADD3, output current detection circuit IS3, and ramp signal I c3 Each is electrically connected to adder ADD3, which is electrically connected to comparator CMP3; the inductor current detection circuit IS1, output current detection circuit IS2, and output current detection circuit IS3 are respectively connected to the corresponding single-inductor three-output switching converter.
2. The current ripple control system for a single-inductor three-output switching converter according to claim 1, characterized in that, The converter TD is a Buck converter.
3. The current ripple control system for a single-inductor three-output switching converter according to claim 1, characterized in that, The converter TD is a Boost converter.
4. The current ripple control system for a single-inductor three-output switching converter according to claim 1, characterized in that, The converter TD is a Buck-Boost converter.
5. A current ripple control method for a single-inductor three-output switching converter, characterized in that, This is achieved through a single-inductor three-output switching converter current ripple control system as described in any one of claims 1-4, with the control flow as follows: S1: The inductor current ripple controller CTR1 detects the output voltage V of the single-inductor three-output switching converter. oa The inductor current detection circuit detects the inductor current I. L ; The output current ripple controller CTR2 detects the output voltage V of the single-inductor three-output switching converter. ob The output current detection circuit detects the output current I. ob ; The output current ripple controller CTR3 detects the output voltage V of the single-inductor three-output switching converter. oc The output current detection circuit detects the output current I. oc ; S2: Output voltage V oa and reference voltage V ref1 The error signal V is amplified by error amplifier EAP1. e1 The current I fed into the positive input terminal of comparator CMP1 is the inductor current. L and ramp signal I c1 The inductor current I after compensation is obtained through adder ADD1. Lc The voltage is fed into the negative input terminal of comparator CMP1; the output voltage V ob and reference voltage V ref2 The error signal V is amplified by error amplifier EAP2. e2 The current I is fed into the positive input terminal of comparator CMP2, and the output current is... ob and ramp signal I c2 The output current I after compensation is obtained through adder ADD2 bc The voltage is fed into the negative input terminal of comparator CMP2; the output voltage V oc and reference voltage V ref3 The error signal V is amplified by error amplifier EAP3. e3 The current I is fed into the positive input terminal of comparator CMP3, and the output current is... oc and ramp signal I c3 The output current I after compensation is obtained through adder ADD3 cc The signal is fed into the negative input terminal of comparator CMP3; S3: I Lc and V e1 The comparison result is sent to the S terminal of RS flip-flop TGR1; I bc and V e2 The comparison result is sent to the S terminal of RS flip-flop TGR2; I cc and V e3 The comparison result is sent to the S terminal of RS flip-flop TGR3; S4: Clock signal CLK is sent to the R terminal of RS flip-flop TGR1; clock signal CLK is sent to the R terminal of RS flip-flop TGR2; clock signal CLK is sent to the R terminal of RS flip-flop TGR3; S5: The Q output signal of RS flip-flop TGR1 is used to obtain the control signal of switch S1, which controls the turn-on and turn-off of switch S1 in switch converter TD via drive circuit DR1; the output signal of RS flip-flop TGR2 is used to obtain the control signal of switch S2, which controls the turn-on and turn-off of switch S2 in switch converter TD via drive circuit DR2; the Q output signal of RS flip-flop TGR3 is used to obtain the control signal of switch S3, which controls the turn-on and turn-off of switch S3 in switch converter TD via drive circuit DR3.