Multi-port fast charging system
By introducing a single-inductor multi-output control chip into a multi-port fast charging system and rationally distributing the transformer demagnetization energy, the low efficiency and resource waste problems of the existing multi-port fast charging system are solved, and efficient and accurate multi-port power control is achieved.
Patent Information
- Application Number
- CN202510837476.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-20
- Publication Date
- 2025-09-12
AI Technical Summary
Existing multi-port fast charging systems have problems such as low system efficiency, resource waste, poor current sharing control accuracy, slow dynamic response and backflow when charging simultaneously, and cannot meet the simultaneous charging needs of multiple mobile terminal devices.
A multi-port fast charging system based on an AC/DC switching power supply architecture is adopted, using a single inductor multiple output (SIMO) control chip. By rationally controlling the transformer demagnetization energy and distributing it on demand among multiple USB ports, combined with the on and off of the left and right switching tubes, efficient distribution of the transformer demagnetization energy is achieved.
It significantly improves power efficiency and power density, reduces the overall cost of the device, solves the problems of low efficiency and resource waste in multi-port fast charging systems, and achieves precise power control of each USB port.
Smart Images
Figure CN120638577A_ABST
Abstract
Description
Technical Field
[0001] The present invention generally relates to the field of circuits, and more particularly to a multi-port fast charging system. Background Art
[0002] With the increasing variety of mobile devices, users are increasingly demanding the ability to simultaneously charge multiple devices using a single fast-charging system. However, single-port fast-charging systems cannot meet the demand for simultaneous charging of multiple mobile devices, making highly integrated multi-port fast-charging systems the optimal solution. Summary of the Invention
[0003] According to an embodiment of the present invention, a multi-port fast charging system is provided, wherein the multi-port fast charging system is based on an AC / DC switching power supply architecture and includes a single inductor multiple output (SIMO) control chip and multiple USB ports. Each of the multiple USB ports is connected to the SIMO control chip via a corresponding left switch tube and a right switch tube. The left switch tube is used for anti-backfeeding function, and the right switch tube is used for power distribution function. The SIMO control chip is configured to distribute the demagnetization energy of the transformer in the AC / DC switching power supply architecture to multiple USB ports by controlling the conduction and shutdown of the left switch tube and the right switch tube connected to each of the multiple USB ports. BRIEF DESCRIPTION OF THE DRAWINGS
[0004] 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:
[0005] Figure 1 A schematic block diagram of the system architecture of a traditional multi-port fast charging system is shown.
[0006] Figure 2 A schematic block diagram of another system architecture of a traditional multi-port fast charging system is shown.
[0007] Figure 3 A schematic block diagram of the system architecture of a traditional single-port fast charging system is shown.
[0008] Figure 4 Shown Figure 3 The following are example waveforms of multiple signals of a single-port fast charging system in intermittent working mode.
[0009] Figure 5 A schematic block diagram shows the system architecture of a multi-port fast charging system according to an embodiment of the present invention.
[0010] Figure 6 Shown Figure 5FIG. 1 is a schematic block diagram of an exemplary implementation of a circuit portion related to energy distribution between various USB ports in a SIMO control chip.
[0011] Figure 7 Shown Figure 5 The following are example waveforms of multiple signals of a multi-port fast charging system in intermittent working mode.
[0012] Figure 8 Shown Figure 5 The waveform diagram shows an example switching timing of the left switch tube and the right switch tube connected to USB port 1 and USB port 2.
[0013] Figure 9A and Figure 9B Shown Figure 5 A schematic diagram of an example connection method between the left switch tube and the right switch tube connected to each USB port is shown. DETAILED DESCRIPTION
[0014] 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 in order 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, well-known structures and technologies are not shown in order to avoid unnecessary ambiguity in the present invention. In addition, it should be noted that the term "A is connected to B" used herein can mean "A is directly connected to B" or "A is indirectly connected to B via one or more other elements."
[0015] Figure 1 The schematic block diagram of the system architecture of a traditional multi-port fast charging system is shown in FIG. Figure 1As shown, in the multi-port fast charging system 100, the power supply DC voltage is first output through a single AC / DC module, and then different charging DC voltages are output through multiple independent DC / DC modules. For example, when the multi-port fast charging system 100 is implemented as a dual-port fast charging system with a maximum output power of 60W, the advantage of this solution is that when only one Universal Serial Bus (USB) port is plugged into a mobile terminal device, the maximum power that the USB port can output is 60W, and when both USB ports are plugged into mobile terminal devices at the same time, the maximum power that each USB port can output is 30W. The disadvantage of this solution is that an additional DC / DC module is required, and the system energy efficiency is about 8% lower than that of a traditional single-port fast charging system. In addition, when both USB ports are plugged into mobile terminal devices at the same time, the maximum output power of each USB port is only 30W, which is a waste of resources for the power device selection to support a DC / DC module with a maximum output power of 60W.
[0016] Figure 2 FIG1 shows a schematic block diagram of another system architecture of a traditional multi-port fast charging system. Figure 2 As shown, in the multi-port fast charging system 200, multiple independent AC / DC modules are connected in parallel, and a parallel switch module is connected between any two AC / DC modules. The control chip connected to each AC / DC module distributes power by adjusting the output voltage of the corresponding AC / DC module. For example, when the multi-port fast charging system 200 is implemented as a dual-port fast charging system with a maximum output power of 60W, the advantage of this solution is that when only one USB port is plugged into a mobile terminal device, the maximum power that the USB port can output is 60W. Figure 1The solution shown here eliminates the need for a DC / DC module and offers high system energy efficiency. When both USB ports are connected simultaneously, the maximum output power per USB port is 30W, and the power device selection supports an AC / DC module with a maximum output power of 30W. However, this solution requires an additional parallel switch module between the AC / DC modules when only one USB port is connected to a mobile device. Furthermore, the accuracy of current sharing depends on the voltage regulation step size of the control chip connected to each AC / DC module and the impedance of the parallel switch module. For example, if the control chip's voltage regulation step size is 10mV and the impedance of the parallel switch module is 10mohm, each voltage regulation step increase or decrease in the output voltage of the AC / DC module by the control chip will increase or decrease the current flowing through the parallel switch module by 10mV / 10mohm (i.e., 1A). The output power of consumer electronics adapters typically ranges from 18W to 120W, corresponding to an output current of 1A to 6A. Therefore, current sharing is poor. To increase the current sharing to 0.1A, the control chip's voltage regulation step for the output voltage of the corresponding AC / DC module needs to be reduced to 1mV, which will greatly increase the internal resources of the control chip; or the impedance of the parallel switch module needs to be increased to 100mohm, which will reduce the system energy efficiency and will not solve the power supply open-loop problem caused by backflow.
[0017] exist Figure 2 In the multi-port fast-charging system 200 shown, to prevent the output voltage from flowing back when unloaded or lightly loaded, causing the power supply to open-loop, the parallel switch module is in the off state by default. When a USB port is suddenly loaded (i.e., a mobile terminal device is suddenly inserted), it cannot be changed from the off state to the on state in real time, resulting in a large undershoot of the output voltage of the corresponding AC / DC module. Therefore, there is also the problem of poor output dynamic response in the current sharing mode. In addition, after the control chip connected to each AC / DC module collects the voltage and current information of the corresponding AC / DC module, several bytes of data need to be exchanged between them to transmit the collected voltage and current information. This has problems such as slow communication speed, delayed interactive information, and susceptibility to interference, making it impossible to accurately control each AC / DC module in real time.
[0018] In order to solve one or more problems existing in the above-mentioned multi-port fast charging system, a multi-port fast charging system according to an embodiment of the present invention is proposed, wherein a single inductor multiple output (SIMO) control chip is added on the basis of the AC / DC switching power supply architecture. Through the reasonable control of the SIMO control chip, the demagnetization energy of the transformer in a single cycle is distributed on demand among multiple USB ports, which can significantly improve the power supply efficiency and power density while reducing the cost of the entire machine.
[0019] Figure 3 The schematic block diagram of the system architecture of a traditional single-port fast charging system is shown. Figure 3 As shown, the single-port fast charging system 300 is based on an AC / DC switching power supply architecture, wherein the fast charging control chip obtains the voltage and current requirements of the device to be charged from the USB port through the DP / DN / CC1 / CC2 pins, adjusts its internal reference voltage and reference current based on the voltage and current requirements of the device to be charged, detects the output voltage Vo of the USB port through the Vin pin, detects the output current Io of the USB port through the HCSN pin (not shown in the figure), and compares the output voltage Vo and output current Io of the USB port with their internal reference voltage and reference current respectively. Finally, the power loop compensation network composed of the VFB / IFB / OPTO pins and the peripheral devices connected to them feeds back the signal related to the output power of the USB port to the pulse width modulation (PWM) controller on the primary side of the transformer T1 through the optocoupler, so that the USB port can output a stable voltage and current required by the device to be charged.
[0020] exist Figure 3 In the fast charging control chip shown, the first operational amplifier generates an operational amplifier signal based on the output voltage feedback signal representing the output voltage Vo of the USB port and its corresponding reference signal, and outputs it to the OPTO pin. The resistor-capacitor circuit between the VFB pin and the OPTO pin and the first operational amplifier together constitute a feedback compensation network Z1; the second operational amplifier generates an operational amplifier signal based on the output current feedback signal representing the output current Io of the USB port and its corresponding reference signal, and outputs it to the OPTO pin. The resistor-capacitor circuit between the IFB pin and the OPTO pin and the second operational amplifier together constitute a feedback compensation network Z2; the feedback compensation networks Z1 and Z2 act on the optocoupler OC through the OPTO pin to transmit the signal related to the output power of the USB port to the FB pin of the PWM controller on the primary side of the transformer T1, thereby achieving the purpose of regulating the output voltage and output current of the USB port. Here, the upper end of the optocoupler OC is usually powered directly by the USB port's output voltage Vo through resistor R1 (not shown). This has the advantage that when the USB port's output voltage Vo changes, the feedback compensation network Z1 / Z2 can be skipped and the optocoupler OC can directly affect the PWM controller on the primary side of transformer T1 to adjust the total output power of the USB port, thus providing feedforward compensation.
[0021] Figure 4 Shown Figure 3The figure shows an example waveform diagram of multiple signals of a single-port fast charging system in intermittent working mode, where PWM_gate represents the power switch control signal for controlling the on and off of the power switch tube Q1, IL_pri represents the charging current of the primary side inductor Lp of the transformer T1, SR_gate represents the synchronous rectification control signal for controlling the on and off of the synchronous rectifier tube Q2, and IL_sec represents the discharge current of the secondary side inductor Ls of the transformer T1.
[0022] like Figure 3 and Figure 4 As shown, the working process of the single-port fast charging system 300 includes: at time t0, the power switch control signal PWM_gate changes from low level to high level, the power switch tube Q1 changes from off state to on state, the bus voltage Vbulk starts to charge the primary side inductor Lp of the transformer T1, and the charging current IL_pri starts to increase; at time t1, the power switch control signal PWM_gate changes from high level to low level, the power switch tube Q1 changes from on state to off state, the synchronous rectification control signal SR_gate changes from low level to high level, and the synchronous rectifier tube Q2 changes from off state to on state. In the state, the output voltage Vo at the USB port discharges (i.e., demagnetizes) the secondary-side inductor Ls of the transformer T1, and the discharge current (i.e., demagnetization current) IL_sec begins to decrease; at time t2, the discharge current IL_sec decreases to 0, the synchronous rectification control signal SR_gate changes from a high level to a low level, and the synchronous rectifier Q2 changes from an on state to an off state; from time t2 to time t3, both the power switch Q1 and the synchronous rectifier Q2 are in the off state; at time t3, the power switch control signal PWM_gate changes from a low level to a high level, and the above working process is repeated in sequence.
[0023] Figure 5 FIG2 shows a schematic block diagram of the system architecture of a multi-port fast charging system according to an embodiment of the present invention. Figure 5As shown, the multi-port fast charging system 500 is based on an AC / DC switching power supply architecture and includes a SIMO control chip 502 and multiple USB ports (for example, USB ports 1 to n, where n is an integer greater than or equal to 2), wherein each USB port is connected to the SIMO control chip 502 via corresponding two switching tubes (for example, the left switching tube Gate iL and the right switching tube Gate iR, where i is an integer greater than or equal to 1 and less than or equal to n), the right switching tube Qi_R is used for power distribution function, and the left switching tube Qn_L is used for anti-backflow function (i.e., preventing the formation of a large current path between the USB ports due to different output voltages), and the SIMO control chip 502 is configured to distribute the demagnetization energy of the transformer T1 in the AC / DC switching power supply architecture to multiple USB ports by controlling the conduction and shutdown of the left switching tube and the right switching tube connected to each USB port.
[0024] like Figure 5 As shown, in some embodiments, each USB port is also connected to the circuit reference ground via a corresponding voltage stabilizing filter capacitor (eg, voltage stabilizing filter capacitor Ci, where i is an integer greater than or equal to 1 and less than or equal to n).
[0025] like Figure 5 As shown, in some embodiments, the SIMO control chip 502 is further configured to distribute a portion of the demagnetization energy of the transformer T1 to any USB port by controlling the left switch tube and the right switch tube connected to the USB port to be in the on state during the demagnetization period of the transformer T1 in each cycle.
[0026] like Figure 5 As shown, in some embodiments, the SIMO control chip 502 is further configured to control the right switch connected to only one USB port among the multiple USB ports to be in the on state at the same time.
[0027] like Figure 5 As shown, in some embodiments, the SIMO control chip 502 is further configured to, for two USB ports among the multiple USB ports that are successively allocated a portion of the demagnetization energy of the transformer T1: after the left switch tube connected to the first USB port of the two USB ports changes from the on state to the off state, control the left switch tube connected to the second USB port of the two USB ports to change from the off state to the on state; and before the right switch tube connected to the first USB port changes from the on state to the off state, control the right switch tube connected to the second USB port to change from the off state to the on state, wherein the first USB port is allocated a portion of the demagnetization energy of the transformer T1 earlier than the second USB port.
[0028] like Figure 5 As shown, in some embodiments, the SIMO control chip 502 performs the following functions for each USB port:
[0029] 1) The voltage and current requirements of the device 1 to be charged inserted into USB port 1 are obtained from USB port 1 via the Port1 BUS pin of the SIMO control chip 502 and the DP / DN / CC1 / CC2 pins of USB port 1. Based on the voltage and current requirements of the device 1 to be charged, the corresponding reference voltage and reference current within the SIMO control chip 502 are adjusted. The output voltage Vo_1 of the USB port 1 is detected via the Vo_1 pin, and the output current Io_1 of the USB port 1 is detected via the HCSN1 pin (not shown in the figure). The output voltage Vo_1 and output current Io_1 of the USB port 1 are compared with the corresponding reference voltage and reference current within the SIMO control chip 502, respectively. Finally, a power loop compensation network consisting of the VFB / IFB / OPTO pins and the peripheral devices connected thereto is used to feed back a signal related to the output power of the USB port 1 to the PWM controller on the primary side of the transformer T1 via the optocoupler OC, thereby enabling the USB port 1 to output the voltage and current required by the device 1 to be charged.
[0030] 2) The voltage and current requirements of device 2 to be charged are obtained from USB port 2 via the Port 2BUS pin of the SIMO control chip 502 and the DP / DN / CC1 / CC2 pins of USB port 2. Based on the voltage and current requirements of device 2 to be charged, the corresponding reference voltage and reference current within the SIMO control chip 502 are adjusted. The output voltage Vo_2 of USB port 2 is detected via the Vo_2 pin, and the output current Io_2 of USB port 2 is detected via the HCSN1 pin. The output voltage Vo_2 and output current Io_2 of USB port 2 are compared with the corresponding reference voltage and reference current within the SIMO control chip 502, respectively. Finally, a power loop compensation network consisting of the Comp2 and OPTO pins and the peripheral devices connected thereto is used to feed back a signal related to the output power of USB 2 to the PWM controller on the primary side of transformer T1 via the optocoupler OC, thereby ensuring that USB port 2 outputs the voltage and current required by device 2 to be charged.
[0031] 3) The control principle for USB port 3 to USB port n is the same as that for USB port 2, and will not be repeated here.
[0032] Figure 6 Shown Figure 5 FIG. 1 is a schematic block diagram of an exemplary implementation of a circuit portion in a SIMO control chip related to energy distribution between various USB ports. Figure 6As shown, in some embodiments, for any USB port i, Figure 5 The SIMO control chip 502 shown can execute the following control scheme: using the transconductance operational amplifier EA_i, based on the output voltage feedback signal Vfb_i representing the output voltage Vo_i of the USB port i and its corresponding reference signal Vref_cvi, generates an output voltage compensation signal Vcomp_i; using the sawtooth wave generator, based on the inductor demagnetization characterization signal Vd representing the demagnetization condition of the secondary side inductor Ls of the transformer T1, generates an on-time characterization signal Vsw representing the duration of time the synchronous rectifier Q2 is in the on state; using the power distribution network, based on the output voltage compensation signal Signal Vcom_i determines the proportion of the duration of the right-side switch tube Gate_iR connected to the USB port i being in the on-state in the duration of the synchronous rectifier tube Q2 being in the on-state (that is, the proportion of the output energy of the USB port i in the demagnetization energy of the secondary-side inductor Ls of the transformer T1), and generates a port proportion control signal (not shown in the figure) based on the determined proportion and the conduction time characterization signal Vsw; and uses the output switch control unit to generate switch control signals Gate_iL and Gate_iR for controlling the conduction and shutoff of the left-side switch tube GateiL and the right-side switch tube Gate iR connected to the USB port i, respectively, based on the port proportion control signal.
[0033] Figure 7 Shown Figure 5 The figure shows an example waveform diagram of multiple signals of a multi-port fast charging system in a discontinuous working mode, wherein PWM_gate represents a power switch control signal for controlling the on and off of the power switch tube Q1, IL_pri represents the charging current of the primary side inductor Lp of the transformer T1, SR_gate represents the synchronous rectification control signal for controlling the on and off of the synchronous rectifier tube Q2, IL_sec represents the discharge current of the secondary side inductor Ls of the transformer T1, Gate 1L and Gate 1R respectively represent the switch control signals for controlling the on and off of the left switch tube Gate 1L and the right switch tube Gate 1R connected to USB port 1, Gate 2L and Gate 2R respectively represent the switch control signals for controlling the on and off of the left switch tube Gate 2L and the right switch tube Gate 2R connected to USB port 2, and Gate nL and Gate nR respectively represent the switch control signals for controlling the on and off of the left switch tube Gate nL and the right switch tube Gate connected to USB port n. The switch control signal for turning on and off nR.
[0034] like Figure 5 and Figure 7As shown, the working process of the multi-port fast charging system 500 includes: at time t0, the power switch control signal PWM_gate changes from low level to high level, the power switch tube Q1 changes from off state to on state, the bus voltage Vbulk charges the primary side inductor Lp of the transformer T1, and the charging current IL_pri begins to increase; at time t1, the power switch control signal PWM_gate changes from high level to low level, the power switch tube Q1 changes from on state to off state, the synchronous rectification control signal SR_gate changes from low level to high level, the synchronous rectifier tube Q2 changes from off state to on state, and the output voltage Vo_1 to V o_n discharges the secondary-side inductor Ls of transformer T1, and the discharge current IL_sec begins to decrease. From time t1 to time t2, the decreasing slope of the discharge current IL_sec varies with the output voltage of different USB ports. After the discharge current IL_sec decreases to 0, the synchronous rectification control signal SR_gate changes from a high level to a low level at time t2, and the synchronous rectifier Q2 changes from an on state to an off state at time t2. From time t2 to time t3, both the power switch Q1 and the synchronous rectifier Q2 are in the off state. At time t3, the power switch control signal PWM_gate changes from a low level to a high level, and the above working process is repeated.
[0035] like Figure 5 and Figure 7As shown, assuming that USB port 1 to USB port n output energy in sequence under the control of the SIMO control chip 502, the working process of the multi-port fast charging system 500 includes: during the period from time t1 to time tm1, the SIMO control chip 502 controls the switch tubes Q1_L and Q1_R to be in the on state and controls the switch tubes Q2_L to Qn_L and Q2_R to Qn_R to be in the off state, and discharges the secondary side inductor Ls of the transformer T1 through the output voltage Vo_1 of the USB port 1, and the discharge current IL_sec flows to the USB port 1, that is, the demagnetization energy of the secondary side inductor Ls of the transformer T1 is distributed to the USB port 1; during the period from time tm1 to time tm2, the SIMO control chip 502 controls the switch tubes Q2_L and Q2_R to be in the on state and controls the switch tubes Q1_L, Q3_R to be in the off state. _L to Qn_L, Q1_R, and Q3_R to Qn_R are in the off state, and the secondary inductor Ls of the transformer T1 is discharged through the output voltage Vo_2 of USB port 2. The discharge current IL_sec flows to USB port 2, that is, the demagnetization energy of the secondary inductor Ls of the transformer T1 is distributed to USB port 2. During the period from time tm2 to time t2, the SIMO control chip 502 controls the switch tubes Qn_L and Qn_R to be in the on state and controls the switch tubes Q1_L to Q(n-1)_L and Q1_R to Q(n-1)_R to be in the off state. The secondary inductor Ls of the transformer T1 is discharged through the output voltage Vo_n of USB port n, and the discharge current IL_sec flows to USB port n. That is, the demagnetization energy of the secondary inductor Ls of the transformer T1 is distributed to USB port n.
[0036] As can be seen from the above description, the multi-port fast charging system 500 can distribute the demagnetization energy of the secondary-side inductor Ls of the transformer T1 to one or more USB ports as needed within a single switching cycle, thereby enabling different USB ports to independently output different output voltages. The order in which the USB ports output energy can be changed based on actual needs and the specific control strategy of the SIMO control chip 502. For example, if USB port 2 requires an output power of 50W and the other USB ports are unloaded (the total required power of these USB ports is less than 0.1W), the demagnetization energy of the secondary-side inductor Ls of the transformer T1 will be allocated to USB port 2 during most of the switching cycles, and only the demagnetization energy in very few cycles will be allocated to the other USB ports.
[0037] Due to the limitations of actual switching devices, a certain dead time is usually reserved to ensure power supply safety. Figure 8 Shown Figure 5The waveform diagram shows an example switching timing of the left and right switch tubes connected to USB port 1 and USB port 2, where IL_sec represents the discharge current of the secondary-side inductor Ls of transformer T1, Gate 1L and Gate 1R respectively represent the switch control signals for controlling the on / off of the left switch tube Gate 1L and the right switch tube Gate 1R connected to USB port 1, and Gate 2L and Gate 2R respectively represent the switch control signals for controlling the on / off of the left switch tube Gate 2L and the right switch tube Gate 2R connected to USB port 2.
[0038] like Figure 8 As shown, when USB port 1 and USB port 2 are sequentially allocated a portion of the demagnetization energy of transformer T1's secondary inductor Ls, a time interval Δt1 = Δt must be maintained between the turn-off time of the left switch Q1_L connected to USB port 1 and the turn-on time of the left switch Q2_L connected to USB port 2 to prevent a path from forming between USB port 1 and USB port 2, potentially damaging the switches. Furthermore, to maintain a path for the demagnetization energy of transformer T1's secondary inductor Ls, the turn-on time of the right switch Q1_R connected to USB port 1 must precede time t1, when the discharge current IL_sec begins to decrease (i.e., when transformer T1's secondary inductor Ls begins to demagnetize). The turn-off time of the right switch Q2_R connected to USB port 2 must be later than time t2, when the discharge current IL_sec reaches zero (i.e., when transformer T1's secondary inductor Ls completes demagnetization). There is a time overlap between the turn-off time of the right switch Q1_R connected to USB port 1 and the turn-on time of the right switch Q2_R connected to USB port 2, that is, it is necessary to ensure that they have a common turn-on time Δt2=Δt, where Δt1 and Δt2 can be different.
[0039] Figure 9A and Figure 9B Shown Figure 5 The diagram shows an example connection method between the left switch tube and the right switch tube connected to each USB port. Figure 9A and Figure 9B As shown, in some embodiments, a back-to-back switching method can be adopted between the left switch tube and the right switch tube connected to each USB port, that is, the source or drain of the two switch tubes are connected together, and the left switch tube and the right switch tube connected to each USB port can adopt N-type or P-type metal oxide semiconductor field effect transistors (N-MOSFET or P-MOSFET), or semiconductor power devices such as GaN or SiC.
[0040] In some embodiments, Figure 5The AC / DC switching power supply architecture shown can adopt a flyback architecture, a boost architecture, a buck architecture, or a buck-boost architecture, and can also adopt their variants, such as a zero-voltage turn-on flyback switching power supply architecture, an asymmetric half-bridge flyback switching power supply architecture, etc.
[0041] 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, and the scope of the present invention is defined by the appended claims rather than the foregoing description. All modifications that come within the meaning and scope of the claims and equivalents are intended to be included within the scope of the present invention.
Claims
1. A multi-port fast charging system, wherein: The multi-port fast charging system is based on an AC / DC switching power supply architecture and includes a single inductor multiple output (SIMO) control chip and multiple USB ports. Each of the multiple USB ports is connected to the SIMO control chip via a corresponding left switch tube and a right switch tube. The left switch tube is used for anti-backfeeding function, and the right switch tube is used for power distribution function. The SIMO control chip is configured to distribute the demagnetization energy of the transformer in the AC / DC switching power supply architecture to the multiple USB ports by controlling the conduction and shutdown of the left switch tube and the right switch tube connected to each of the multiple USB ports.
2. The multi-port fast charging system according to claim 1, wherein: Each of the plurality of USB ports is further connected to a circuit reference ground via a corresponding voltage stabilizing filter capacitor.
3. The multi-port fast charging system according to claim 1, wherein: The SIMO control chip is further configured to distribute a portion of the demagnetization energy of the transformer to any one of the multiple USB ports by controlling the left switch tube and the right switch tube connected to the USB port to be in an on state during the demagnetization period of the transformer in each cycle.
4. The multi-port fast charging system according to claim 1, wherein: The SIMO control chip is further configured to control the right switch connected to only one of the multiple USB ports to be in an on state at the same time.
5. The multi-port fast charging system according to claim 1, wherein: The SIMO control chip is further configured to: for two USB ports among the plurality of USB ports that are successively allocated a portion of the demagnetization energy of the transformer: After the left switch connected to the first USB port of the two USB ports changes from the on state to the off state, controlling the left switch connected to the second USB port of the two USB ports to change from the off state to the on state; and Before the right switch tube connected to the first USB port changes from the on state to the off state, the right switch tube connected to the second USB port is controlled to change from the off state to the on state, wherein the first USB port is allocated a portion of the demagnetization energy of the transformer earlier than the second USB port.
6. The multi-port fast charging system according to claim 1, wherein: The AC / DC switching power supply architecture further includes a synchronous rectifier tube, and the SIMO control chip is configured to: generating an output voltage compensation signal based on an output voltage feedback signal representing an output voltage of the USB port and a corresponding reference signal using a transconductance operational amplifier; Using a sawtooth wave generator, based on an inductance demagnetization characterization signal characterizing the demagnetization condition of the secondary-side inductance of the transformer, a conduction time characterization signal characterizing the duration that the synchronous rectifier is in a conduction state is generated; Determining, using a power distribution network, based on the output voltage compensation signal, a proportion of a duration during which the right-side switch tube connected to the USB port is in an on-state relative to a duration during which the synchronous rectifier tube is in an on-state, and generating a port proportion control signal based on the determined proportion and the on-time characterization signal; as well as The output switch control unit is used to generate switch control signals for controlling the on and off of the left switch tube and the right switch tube connected to the USB port based on the port ratio control signal.
7. The multi-port fast charging system according to claim 1, wherein: The AC / DC switching power supply architecture includes a pulse width modulation controller, and the SIMO control chip is configured to: Obtaining voltage and current requirements of a device to be charged plugged into the USB port, and adjusting corresponding reference voltage and reference current within the SIMO control chip based on the voltage and current requirements of the device to be charged; Detecting the output voltage and output current of the USB port, and comparing the output voltage and output current of the USB port with corresponding reference voltage and reference current inside the SIMO control chip; A signal related to the output power of the USB port is fed back to the pulse width modulation controller via an optical coupler through a power loop compensation network.
8. The multi-port fast charging system according to claim 1, wherein: The AC / DC switching power supply architecture adopts one of a flyback architecture, a boost architecture, a buck architecture, or a buck-boost architecture.
9. The multi-port fast charging system according to claim 1, wherein: The left switch tube and the right switch tube connected to any one of the multiple USB ports are N-MOSFET, P-MOSFET, or GaN or SiC semiconductor power devices.
10. The multi-port fast charging system according to claim 1, wherein: For any one USB port among the multiple USB ports, the source or drain of the left switch tube and the right switch tube connected to the USB port are connected together.