Power supply system of single-inductor multi-output architecture and control device applied to power supply system

Abstract

The invention discloses a power supply system of a single-inductor multi-output architecture and a control device applied to the power supply system. The power supply system comprises a transformer, an output voltage controller, a switch connected to a primary side of the transformer and a plurality of output ports connected to a secondary side of the transformer, and the control device comprises a plurality of voltage acquisition interfaces which are respectively connected to the plurality of output ports to receive a plurality of corresponding output voltages; a feedback voltage generation circuit for generating a feedback voltage based on at least two of the plurality of output voltages; and the feedback voltage output interface is used for being connected to a compensation device of the power supply system, so that the compensation device can control the action of the switch based on the feedback voltage and a compensation signal output by the output voltage controller.

Description

Technical Field

[0001] The present invention relates to the field of circuits, and in particular to a power supply system with a single inductance multi-output (SIMO) architecture and a control device used therein. Background Art

[0002] In the field of switching power supplies, a power supply system with a SIMO architecture is an efficient solution that uses a single inductor to achieve multiple outputs, providing multiple output voltages through multiple output ports. Summary of the Invention

[0003] According to an embodiment of the present invention, a control device for a power supply system applied to a single-inductor multiple-output architecture is provided. The power supply system includes a transformer, a switch connected to the primary side of the transformer, and multiple output ports connected to the secondary side of the transformer. The control device includes: multiple voltage acquisition interfaces, respectively connected to the multiple output ports to receive corresponding multiple output voltages; a feedback voltage generation circuit, used to generate a feedback voltage based on at least two of the multiple output voltages; and a feedback voltage output interface, used to be connected to a compensation device of the power supply system, so that the compensation device can control the action of the switch based on the feedback voltage and a compensation signal output by an output voltage controller of the power supply system.

[0004] A power supply system with a SIMO architecture according to an embodiment of the present invention includes the aforementioned control device and a pulse width modulation controller for controlling the operation of a switch, wherein the compensation device includes: an optocoupler connected to the control device, for generating a control signal for the pulse width modulation controller based on a feedback voltage and a compensation signal; and a resistor-capacitor network connected between the output voltage controller and the optocoupler. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] The present invention can be better understood from the following description of specific embodiments of the present invention in conjunction with the accompanying drawings, in which:

[0006] Figure 1 A schematic block diagram of a power supply system with a single inductor multiple output architecture according to an embodiment of the present invention is shown.

[0007] Figure 2 and Figure 3 Shown Figure 1 Schematic block diagram and logic diagram of the feedback voltage generation circuit in .

[0008] Figure 4 A schematic block diagram of a power supply system with a single inductor multiple output architecture according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0009] The features and exemplary embodiments of various aspects of the present invention will be described in detail below. In the detailed description below, many specific details are proposed to provide a comprehensive understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the present invention. The present invention is by no means limited to any specific configuration and algorithm proposed below, but covers any modification, replacement, and improvement of elements, components, and algorithms without departing from the spirit of the present invention. In the accompanying drawings and the following description, known structures and techniques are not shown to avoid causing unnecessary ambiguity to the present invention.

[0010] A power supply system with a SIMO architecture provides multiple output voltages through multiple output ports, which may experience transient load changes. Typically, the power supply system's controller receives direct feedback from only one of these output ports, providing a fast dynamic response to load changes at that port. However, when the loads of other output ports experience large transient changes, the controller is only indirectly affected through the power supply system's internal compensation network, including the operational amplifier. This makes it difficult to quickly respond to these load changes, resulting in poor dynamic performance.

[0011] According to an embodiment of the present invention, in a control device of a power supply system applied to a single-inductor multi-output architecture, a feedback voltage generating circuit generates a feedback voltage based on at least two of a plurality of output voltages, so that a compensation device in the power supply system controls the action of a switch in the power supply system based on the feedback voltage. Compared with the original control device which could only quickly and dynamically respond to load changes of an output port receiving direct feedback, the embodiment of the present invention realizes a fast dynamic response of the power supply system to a plurality of or even all output voltages corresponding to the feedback voltage, thereby improving the dynamic response characteristics of the power supply system to the output voltage corresponding to the feedback voltage.

[0012] Figure 1 FIG. 1 shows a schematic block diagram of a power supply system 100 with a single inductor multiple output architecture according to an embodiment of the present invention. Figure 1As shown, the power supply system 100 includes a control device 102, a transformer T1, a switch Q1 connected to the primary side of transformer T1, a pulse width modulation (PWM) controller U1, an output voltage controller U2, a compensation device 106, and multiple output ports Port 1-Port n, where n is an integer greater than 1. The control device 102 includes: multiple voltage acquisition interfaces P11-P1n, respectively connected to the multiple output ports of the power supply system to receive the corresponding multiple output voltages Vo_1-Vo_n; a feedback voltage generation circuit 104, configured to generate a feedback voltage Vo_x based on at least two of the multiple output voltages; and a feedback voltage output interface P2, configured to connect to the compensation device 106 so that the compensation device 106 can control the operation of the switch Q1 based on the feedback voltage Vo_x and a compensation signal S-OPTO output by the output voltage controller U2. Specifically, the compensation device 106 generates a control signal for the PWM controller U1 based on the feedback voltage Vo_x and the compensation signal. The PWM controller U1 controls the operation of the switch Q1 based on the control signal. The compensation signal is an indirect signal output by output voltage controller U2 based on the output voltage. Feedback voltage Vo_x not only powers compensation device 106 but also implements feedforward compensation for power supply system 100. Compensation device 106 controls the operation of switch Q1 based on feedback voltage Vo_x, enabling the power supply system to rapidly respond to feedback voltage Vo_x. This, in turn, dynamically responds to the multiple output voltages corresponding to feedback voltage Vo_x, thereby improving the power supply system's dynamic response to the corresponding output voltages.

[0013] In some embodiments, the feedback voltage generating circuit 104 can be used to generate the feedback voltage Vo_x based on all the output voltages Vo_1-Vo_n of the power system. In this case, the compensation device 106 controls the operation of the switch Q1 based on the feedback voltage Vo_x, thereby achieving a dynamic response to all the output voltages Vo_1-Vo_n.

[0014] Figure 2 and Figure 3 Shown Figure 1 Schematic block diagram and logic diagram of the feedback voltage generating circuit 104 in FIG. Figure 2 and Figure 3 This is an example of generating the feedback voltage Vo_x based on the output voltages Vo_1 -Vo_n of the power supply system. In other embodiments, the feedback voltage Vo_x may be generated based on only a portion of the output voltages Vo_1 -Vo_n.

[0015] In some embodiments, as Figure 2 and Figure 3As shown, the feedback voltage generating circuit 104 may include multiple weighting circuits 202_i (i=1, ..., n) and a summing circuit 204. The weighting circuit 202_i is used to generate a weighted voltage based on the corresponding output voltage Vo_i (i=1, ..., n) according to the corresponding weight value Ki. The summing circuit 204 is used to generate a feedback voltage Vo_x based on the multiple weighted voltages. The weight value Ki of the weighting circuit 202_i can be set according to the amplitude of the output voltage Vo_i and the importance the power supply system attaches to each output voltage. In some embodiments, the weight value Ki of each weighting circuit 202_i is not less than zero. In other embodiments, the weight value of one or more weighting circuits 202_i can be zero, and the weighted voltage output by the weighting circuit 202_i is zero. In this case, the feedback voltage Vo_x is not affected by the output voltage corresponding to the weighting circuit 202_i.

[0016] In some embodiments, as Figure 2 and Figure 3 As shown, the feedback voltage generation circuit 104 may further include multiple reference voltage generation circuits 206_i (i=1, ..., n) and multiple difference circuits 208_i (i=1, ..., n). Each reference voltage generation circuit 206_i is configured to generate a corresponding reference voltage Vref_i. Each difference circuit 208_i is configured to generate a difference voltage Error_i based on a corresponding output voltage Vo_i and a corresponding reference voltage Vref_i, and provide the difference voltage Error_i to a corresponding weighting circuit 202_i.

[0017] In some embodiments, as Figure 3 As shown, each reference voltage generating circuit 206_i may include a digital-to-analog converter DACi (i=1, . . . , n) for generating a corresponding reference voltage Vref_i based on a signal from a digital control circuit.

[0018] In some embodiments, the feedback voltage generating circuit 104 may further include a plurality of voltage dividing circuits for dividing the corresponding output voltage Vo_i, and the divided voltage Vfb_i is provided to the corresponding difference circuit 208_i. Figure 2 and Figure 3 As shown, the voltage divider circuit can be realized by connecting resistors in series.

[0019] In some embodiments, as Figure 2 and Figure 3 As shown, the feedback voltage generating circuit 104 may further include an offset voltage generating circuit 210 for generating an offset voltage Vup. Accordingly, the summing circuit 204 may sum the offset voltage Vup with a plurality of weighted voltages to generate the feedback voltage Vo_x.

[0020] In some embodiments, the voltages related to the feedback voltage generating circuit 104 , such as the offset voltage Vup, the reference voltage Vref_i, and the divided voltage Vfb_i, are generally relatively low, for example, within a voltage range of 2 to 20V.

[0021] According to an embodiment of the present invention, changes in the feedback voltage Vo_x are associated with changes in the corresponding output voltages Vo_i. Therefore, when the compensation device uses the feedback voltage Vo_x as a basis for controlling the switching action, a dynamic response to two or more output voltages corresponding to the feedback voltage Vo_x is achieved.

[0022] Figure 4 FIG. 1 shows a schematic block diagram of a power supply system of a single inductor multiple output architecture according to an embodiment of the present invention. Figure 4 As shown, a SIMO power system 400 includes a transformer T1, a switch Q1 connected to the primary side of transformer T1, multiple output ports Port 1-Port n (n is an integer greater than 1), a control device 402, a pulse width modulation controller U1 for controlling the operation of switch Q1, an output voltage controller U2, and a compensation device. The compensation device includes an optocoupler OC for generating a control signal FB for the pulse width modulation controller U1 based on a feedback voltage Vo_x and a compensation signal; and a resistor-capacitor network connected between the output voltage controller U2 and the optocoupler OC.

[0023] In some embodiments, as Figure 4 As shown, the RC network in the compensation device 404 includes resistors R2 and R3 and capacitors C1 - C4 .

[0024] In some embodiments, as Figure 4 As shown, the compensation device 404 further includes a resistor R1 connected between the control device 402 and the optocoupler OC.

[0025] In some embodiments, as Figure 4 As shown, the power supply system 400 may further include an output voltage controller U2 connected to the RC network. The output voltage controller U2 and the control device 402 may be integrated into the same chip. The output voltage controller U2 may generate a compensation signal based on one or more of the multiple output voltages of the multiple output ports through an operational amplifier (not shown) and a RC network. Specifically, as Figure 4As shown, the RC network portion between the OPTO pin and the IFB pin (related to the current outputted by at least one of the multiple output ports) of the output voltage controller U2 and the corresponding operational amplifier inside the output voltage controller U2 together constitute a feedback compensation network, and the RC network portion between the OPTO pin and the VFB pin (related to the voltage outputted by at least one of the multiple output ports) of the output voltage controller U2 and the corresponding operational amplifier inside the output voltage controller U2 together constitute another feedback compensation network. These two feedback compensation networks output compensation signals through the OPTO pin to act on the optocoupler OC.

[0026] The output voltage controller U2 can also control the on / off between the secondary side of the transformer T1 and each output port through gate signals SR_Gate, Gate iL, and Gate iR (i=1, 2, . . . n) to control the output voltage of each output port Port 1-Port n.

[0027] The present invention may be implemented in other specific forms without departing from its spirit and essential characteristics. For example, the algorithms described in the specific embodiments may be modified without departing from the basic spirit of the present invention. Therefore, the present embodiments are to be considered in all respects as illustrative and not restrictive, the scope of the invention is defined by the appended claims rather than the foregoing description, and all modifications coming within the meaning and scope of equivalents of the claims are intended to be included within the scope of the present invention.

Claims

1. A control device for a power supply system in a single-inductor multiple-output (SIMO) architecture, the power supply system comprising a transformer, an output voltage controller, a switch connected to the primary side of the transformer, and multiple output ports connected to the secondary side of the transformer, the control device comprising: a plurality of voltage acquisition interfaces, configured to be respectively connected to the plurality of output ports to receive a corresponding plurality of output voltages; a feedback voltage generating circuit, configured to generate a feedback voltage based on at least two output voltages of the plurality of output voltages; as well as A feedback voltage output interface is used to connect to a compensation device of the power supply system, so that the compensation device can control the action of the switch based on the feedback voltage and the compensation signal output by the output voltage controller.

2. The control device according to claim 1, wherein: The feedback voltage generating circuit includes: a plurality of weighting circuits for generating a plurality of weighted voltages according to each corresponding weight value of the plurality of weighting circuits based on corresponding ones of the plurality of output voltages; and A summing circuit is connected to the plurality of weighting circuits and is configured to generate the feedback voltage based on the plurality of weighted voltages.

3. The control device according to claim 2, wherein: The feedback voltage generating circuit further includes: a plurality of reference voltage generating circuits for generating a plurality of reference voltages; and Multiple difference circuits are respectively connected to corresponding voltage acquisition interfaces among the multiple voltage acquisition interfaces and corresponding reference voltage generation circuits among the multiple reference voltage generation circuits, and are used to generate multiple difference voltages based on the multiple output voltages and the multiple reference voltages and provide them to the multiple weighting circuits.

4. The control device according to claim 3, wherein: Each of the reference voltage generating circuits includes a digital-to-analog converter for generating a corresponding reference voltage based on a signal from a digital control circuit.

5. The control device according to claim 3, wherein: The feedback voltage generating circuit further includes: An offset voltage generating circuit for generating an offset voltage, The summing circuit is configured to sum the offset voltage and the plurality of weighted voltages to generate the feedback voltage.

6. The control device according to claim 2, wherein: Each corresponding weight value of the plurality of weighting circuits is not less than zero.

7. The control device according to claim 1, wherein: The feedback voltage generating circuit is configured to generate the feedback voltage based on all output voltages.

8. A power supply system with a single-inductor multiple-output architecture, comprising a control device according to any one of claims 1 to 7 and a pulse width modulation controller for controlling the operation of the switch, wherein: The compensation device comprises: a photoelectric coupler connected to the control device, configured to generate a control signal for the pulse width modulation controller based on the feedback voltage and the compensation signal; and A resistor-capacitor network is connected between the output voltage controller and the optocoupler.

9. The power supply system according to claim 8, wherein: The compensation device also includes a first resistor, a first end of the first resistor receives the feedback voltage, a second end of the first resistor is connected to the anode of the light emitter of the photoelectric coupler, a cathode of the light emitter of the photoelectric coupler is connected to the resistor-capacitor network, and the light receiver of the photoelectric coupler sends the control signal to the pulse width modulation controller.

10. The power supply system according to claim 8, wherein: The output voltage controller is configured to generate the compensation signal through an operational amplifier and the resistor-capacitor network based on one or more of the output voltages of the output ports.

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