Control system, docking station and power management method thereof

Abstract

The invention describes a control system, a docking station and a power supply management method thereof, and the method comprises the steps: when an MCU detects that the voltage of a first signal line or a second signal line in the first end of a power adapter is changed from high to low and accords with a disconnection characteristic, judging a pull-out event; the MCU sends a low-level pulse to a fourth signal line in the second end of the docking station; the MCU turns off the second switch and starts the discharging circuit; the terminal equipment starts to output a voltage higher than a first preset value to the third signal line when monitoring that the voltage on the third signal line is reduced to the first preset value; the voltage on the first signal line begins to drop; and when the MCU monitors that the voltage on the first signal line is reduced to be equal to or close to the voltage on the third signal line, the first switch is turned off, and the second switch is turned on. According to the invention, the docking station can realize quick switching of the power supply without increasing extra hardware cost, so that a backup power supply circuit is saved.

Description

Technical Field

[0001] The present invention relates to the technical field of expansion docks, and in particular to a control system, an expansion dock and a power management method thereof. Background Art

[0002] With the popularity of laptops, Type-C interfaces are widely used due to their versatility and high transmission speed. However, existing Type-C docking stations often require additional backup power circuits in their designs to ensure stability and reliability during power switching. This not only increases costs but also limits the miniaturization of devices. Summary of the invention

[0003] The present invention aims to provide a control system, an expansion dock and a power management method thereof, so that the expansion dock can realize rapid switching of power without increasing additional hardware costs, thereby saving a backup power circuit.

[0004] To this end, the first aspect of the present invention provides a power management method for an expansion dock, wherein the first end of the expansion dock is connected to the first end of a power adapter, the second end of the power adapter is connected to a power source, the second end of the expansion dock is connected to a terminal device, and the third end of the expansion dock is connected to a peripheral device. The expansion dock comprises an MCU, a first switch, a second switch, and a discharge circuit. The first signal line in the first end of the expansion dock is respectively connected to the first switch and the MCU, the second signal line in the first end of the expansion dock is connected to the MCU, the third signal line in the second end of the expansion dock is respectively connected to the second switch, the MCU, and the discharge circuit, the fourth signal line in the second end of the expansion dock is connected to the MCU, the MCU is connected to the discharge circuit, and the first switch is connected to the second switch. The method comprises the following steps: the MCU monitors the voltage change of the first signal line or the second signal line in the first end of the power adapter; when the MCU When U detects that the voltage at the first end of the power adapter changes from high to low and meets the disconnection characteristics, it is determined as an unplugging event; the MCU sends a low-level pulse to the fourth signal line in the second end of the expansion dock to initiate an FRS request to the terminal device; the MCU turns off the second switch and starts the discharge circuit, which is used to reduce the voltage on the third signal line; when the terminal device monitors that the voltage on the third signal line drops to a first preset value, it starts to output a voltage higher than the first preset value to the third signal line; when the first end of the expansion dock is disconnected from the first end of the power adapter, or the second end of the power adapter is disconnected from the power supply, the voltage on the first signal line starts to drop; when the MCU monitors that the voltage on the first signal line drops to be equal to or close to the voltage on the three signal lines, the first switch is turned off and the second switch is turned on to enable the terminal device to supply power to the expansion dock.

[0005] In the power management method of the expansion dock involved in the first aspect of the present invention, optionally, the first preset value is 4.75V.

[0006] In the power management method of the expansion dock involved in the first aspect of the present invention, optionally, the terminal device starts to output a voltage of 5V to the third signal line when monitoring that the voltage on the third signal line drops to 4.75V.

[0007] In the power management method of the expansion dock involved in the first aspect of the present invention, optionally, the first signal line is a VBUS_PD signal line (i.e., the power line VBUS at the first end of the expansion dock), the second signal line is a CC_PD signal line (i.e., the CC signal line at the first end of the expansion dock), the third signal line is a VBUS_UFP signal line (i.e., the power line VBUS at the second end of the expansion dock), and the fourth signal line is a CC_UFP signal line (i.e., the CC signal line at the second end of the expansion dock).

[0008] In the power management method of the expansion dock involved in the first aspect of the present invention, optionally, the power adapter inputs a voltage of 5V or 20V to the expansion dock through the first end of the expansion dock.

[0009] In the power management method of the expansion dock involved in the first aspect of the present invention, optionally, the voltage on the third signal line drops to 4.75V within 1000 microseconds, and increases from 4.75V to 5V within 200 microseconds.

[0010] In the power management method of the expansion dock involved in the first aspect of the present invention, optionally, the method also includes: after the terminal device starts to output a voltage higher than the first preset value to the third signal line when monitoring that the voltage on the third signal line drops to a first preset value, the MCU turns off the discharge circuit.

[0011] In the power management method of the expansion dock involved in the first aspect of the present invention, optionally, the expansion dock is an expansion dock with a Type-C interface, the first end of the expansion dock is a first Type-C interface, and the second end of the expansion dock is a second Type-C interface.

[0012] A second aspect of the present invention provides an expansion dock, wherein a first end of the expansion dock is connected to a first end of a power adapter, a second end of the power adapter is connected to a power source, a second end of the expansion dock is connected to a terminal device, and a third end of the expansion dock is connected to a peripheral device. The expansion dock includes an MCU, a first switch, a second switch, and a discharge circuit. A first signal line in the first end of the expansion dock is respectively connected to the first switch and the MCU, a second signal line in the first end of the expansion dock is connected to the MCU, a third signal line in the second end of the expansion dock is respectively connected to the second switch, the MCU, and the discharge circuit, a fourth signal line in the second end of the expansion dock is connected to the MCU, the MCU is connected to the discharge circuit, the first switch is connected to the second switch, and the expansion dock is used to execute the method described in the first aspect.

[0013] A third aspect of the present invention provides a control system, which includes a power supply, a power adapter, a terminal device, a peripheral device, and the expansion dock described in the second aspect.

[0014] In the control system, expansion dock and power management method thereof involved in the present invention, power management is achieved through software control. Compared with the prior art, the backup power circuit can be omitted in the expansion dock, thereby reducing costs and improving the reliability and miniaturization of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The invention will now be explained in further detail, by way of example only, with reference to the accompanying drawings.

[0016] Figure 1 1 is a functional block diagram showing a control system according to an example of the present invention.

[0017] Figure 2 1 is a functional module diagram of a docking station involved in the prior art.

[0018] Figure 3 2 is a functional module diagram of a docking station according to an example of the present invention.

[0019] Figure 4 is a flow chart showing a power management method of a docking station according to an example of the present invention. DETAILED DESCRIPTION

[0020] Hereinafter, with reference to the accompanying drawings, the preferred embodiments of the present invention will be described in detail. In the following description, the same symbols are given to the same components, and repeated descriptions are omitted. In addition, the accompanying drawings are only schematic diagrams, and the ratio of the dimensions of the components or the shapes of the components may be different from the actual ones.

[0021] It should be noted that the terms "including" and "having" and any variations thereof in the present invention, such as a process, method, system, product or device that includes or has a series of steps or units, are not necessarily limited to those steps or units clearly listed, but may include or have other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0022] Reference Figure 1 The present invention provides a control system, which includes a power supply 5, a power adapter 2, a terminal device 3, a peripheral device 4, and an expansion dock 1.

[0023] In some embodiments, the terminal device 3 may be a laptop computer, a desktop computer, a mobile phone, a tablet, etc.

[0024] In some embodiments, the peripheral device 4 may be a display, a USB flash drive, a USB mobile hard drive, a keyboard, a mouse, etc.

[0025] Reference Figure 2In the existing docking station, a backup power circuit 70 is usually provided, wherein the first end of the docking station 1 is connected to the first end of the power adapter 2, the second end of the power adapter 2 is connected to the power supply 5, the second end of the docking station 1 is connected to the terminal device 3, the third end of the docking station 1 is connected to the peripheral device 4, and the docking station 1 includes an MCU10, a first switch 30, a second switch 40, and a discharge circuit 20. The first signal line in the first end of the docking station 1 is respectively connected to the first switch 30 and the MCU10, and the second signal line in the first end of the docking station 1 is connected to the MCU10. The third signal line in the second end of the docking station 1 is respectively connected to the second switch 30, the MCU10, and the discharge circuit 20, and the fourth signal line in the second end of the docking station 1 is connected to the MCU10. The MCU10 is connected to the discharge circuit 20. The first switch 30 and the second switch 40 are connected. In addition, the first switch 30 and the second switch 40 are interconnected with the system power management module 60. The system power management module 60 is connected to the backup power circuit 70. The interconnection end 50 of the first switch 30 and the second switch 40 and the system power management module 60 is VBUS_M.

[0026] The first switch is SW_PD (Switch for Power Delivery). The second switch is SW_UFP (Switch for USB Type-C Upstream Facing Port).

[0027] Specifically, at a first end of the docking station 1 and a first end of the power adapter 2 , the docking station 1 and the power adapter 2 communicate via signal lines VBUS_PD and CC_PD.

[0028] At the second end of the docking station 1 , the docking station 1 and the terminal device 3 communicate via signal lines VBUS_UFP and CC_UFP.

[0029] The inventors have found that based on the PD3.0 (Power DeliveryR 3.0) specification, the transition time tSrcFRSwap of the FRS function during RoleSwap (power role switching) is 150uS. If the docking station wants to support the FRS (Fast Role Swap) function well, then a backup power circuit 70 (Backup Power) is required on the docking station to play the role of backup power.

[0030] The backup power circuit 70 is charged slowly at normal times, and is discharged quickly during the tSrcFRSwap period during the FRS to supply power to the following devices: the circuit of the docking station body, and other devices connected to the docking station (such as a USB flash drive, USB mobile hard drive, keyboard, mouse, etc.).

[0031] At present, the expansion docks on the market that support the FRS function, regardless of the type of MCU used (for example, Realtek, Cypress, TI, Synaptics, ITE, Analogloigic, CapStone, Fresco...), when the power adapter 2 charges the terminal device 3 through the expansion dock 1, when the first end of the power adapter 2 (the end where the power adapter 2 is connected to the expansion dock 1) is disconnected, all adopt the following processing method without exception: the first end of the power adapter is disconnected; the MCU10 sends an FRS request to the terminal device; the second switch 40 remains closed, and the first switch 30 changes from closed to open; the voltage at the interconnection end 50 of the first switch 30 and the second switch 40 and the system power management module 60 continues to decrease, and the backup power circuit 70 automatically discharges when the power is insufficient; when the terminal device 3 detects that the voltage at its interface is less than 4.75V, it outputs a 5V voltage, and the RoleSwap is completed.

[0032] However, the backup power circuit 70 is generally composed of an electrolytic capacitor and a peripheral circuit that can control the charging speed. The docking station with the backup power circuit 70 has the following disadvantages: 1. The electrolytic capacitor is large in size and takes up a lot of space. In fact, because the diameter is ≥6.3mm, it is necessary to dig a hole in the PCB board to put it down, and digging a hole can easily lead to difficulties in PCB wiring; 2. The life of the electrolytic capacitor at high temperature is about 2000 to 10000 hours. It has the shortest life in the entire docking station product, so its existence will seriously affect the usable life of the product; 3. The cost of the backup power circuit 70 is between 0.2 and 0.5 yuan, depending on the soft start time of the front-end power chip and whether it is Buck or BuckBoost topology. Although the cost is not large, it is also a considerable expense when the output is relatively large.

[0033] Based on this, the present invention proposes a method that can omit the use of the backup power circuit 70 and only rely on the hardware circuit of the docking station to achieve energy self-sufficiency during the interval of power role switching. In this way, the disadvantages of increased cost and limited device miniaturization caused by the additional use of the backup power circuit 70 in the docking station 1 can be solved.

[0034] Accordingly, the present invention provides a docking station and a power management method thereof.

[0035] The first end of the docking station 1 is connected to the first end of the power adapter 2 , the second end of the power adapter 2 is connected to the power source 5 , the second end of the docking station 1 is connected to the terminal device 3 , and the third end of the docking station 1 is connected to the peripheral device 4 .

[0036] The docking station 1 may include an MCU 10, a first switch 30, a second switch 40, and a discharge circuit 20. The first signal line in the first end of the docking station 1 is respectively connected to the first switch 30 and the MCU 10, and the second signal line in the first end of the docking station 1 is connected to the MCU 10. The third signal line in the second end of the docking station 1 is respectively connected to the second switch 30, the MCU 10, and the discharge circuit 20, and the fourth signal line in the second end of the docking station 1 is connected to the MCU 10. The MCU 10 is connected to the discharge circuit 20. The first switch 30 and the second switch 40 are connected.

[0037] In some embodiments, the docking station 1 is a docking station having a Type-C interface, the first end of the docking station 1 may be a first Type-C interface, and the second end of the docking station 1 may be a second Type-C interface.

[0038] In some embodiments, the first signal line may be a VBUS_PD signal line (i.e., the power line VBUS at the first end of the docking station 1), the second signal line may be a CC_PD signal line (i.e., the CC signal line at the first end of the docking station 1), the third signal line may be a VBUS_UFP signal line (i.e., the power line VBUS at the second end of the docking station 1), and the fourth signal line may be a CC_UFP signal line (i.e., the CC signal line at the second end of the docking station 1).

[0039] When the first end or the second end of the power adapter 2 is unplugged, the docking station 1 can monitor in real time through the MCU 10 that the voltage of the first signal line or the second signal line in the first end of the power adapter 2 changes from high to low, and the MCU 10 will perform the following operations.

[0040] Figure 4 is a flow chart showing a power management method of a docking station according to an example of the present invention.

[0041] Reference Figure 4 , the present invention provides a power management method for an expansion dock 1.

[0042] In some embodiments, the docking station 1, the power adapter 2, the terminal device 3, the peripheral device 4, and the power supply 5 may be connected first.

[0043] In some embodiments, the power management method of the docking station 1 may include: the MCU 10 monitors the voltage change of the first signal line or the second signal line in the first end of the power adapter 2 .

[0044] In some embodiments, the power management method of the docking station 1 may include: when the MCU 10 detects that the voltage of the first signal line or the second signal line in the first end of the power adapter 2 changes from high to low and meets the disconnection characteristics, it is determined as an unplug event. The unplug event may be that the first end of the power adapter 2 is being unplugged from the first end of the docking station but is not completely disconnected from the first end of the docking station. The unplug event may also be that the second end of the power adapter 2 is being unplugged from the power supply 5 but is not completely disconnected from the power supply.

[0045] In some embodiments, when the first end of the docking station 1 is disconnected from the first end of the power adapter 2, a signal line named CC (i.e., the second signal line) inside the cable of the power adapter 2 will be disconnected first because its pin length is 0.5 mm shorter than GND and VBUS. Thus, the MCU 10 can monitor that the voltage of the first signal line in the first end of the power adapter 2 changes from high to low.

[0046] In some embodiments, the power management method of the docking station 1 may include: sending a low level pulse to a fourth signal line in the second end of the docking station 1 through the MCU 10 to initiate a Fast Role Swap (FRS) request to the terminal device 3 .

[0047] In some embodiments, the power management method of the docking station 1 may include: the MCU 10 turns off the second switch 40 and starts the discharge circuit 20. The discharge circuit 20 is used to reduce the voltage on the third signal line or quickly pull down the voltage on the third signal line.

[0048] In some embodiments, the power management method of the docking station 1 may include: when the terminal device 3 detects that the voltage on the third signal line drops to a first preset value, it starts to output a voltage higher than the first preset value to the third signal line.

[0049] In some embodiments, the first preset value may be 4.75V.

[0050] In some embodiments, the terminal device 3 starts to output a voltage of 5V to the third signal line when the voltage on the third signal line is monitored to drop to 4.75V.

[0051] In some embodiments, because the terminal device 3 has previously received the FRS request initiated by the expansion dock 1, when it detects that the voltage on the third signal line has dropped to 4.75V, it will consider that the time is ripe to supply power to the expansion dock, and thus send 5V to the third signal line of the expansion dock.

[0052] In some embodiments, the voltage on the third signal line drops to 4.75V within 1000 microseconds, and rises from 4.75V to 5V within 200 microseconds.

[0053] It is understandable that in the above steps, the first end or the second end of the docking station 1 is not completely unplugged, and at this time, the docking station 1 is still powered normally by the power supply 5 and the power adapter 2.

[0054] In some embodiments, after several mS, the first end of the expansion dock 1 is completely disconnected from the first end of the power adapter 2, or the second end of the power adapter 2 is completely disconnected from the power source 5, at which time the voltage on the first signal line on the expansion dock will enter a decreasing stage from a stable voltage.

[0055] In some embodiments, the power management method of the expansion dock 1 may include: when the MCU 10 detects that the voltage on the first signal line drops to be equal to or close to the voltage on the three signal lines, turning off the first switch 30 (SW_PD) in the expansion dock 1 and turning on the second switch 40 so that the terminal device 3 supplies power to the expansion dock 1.

[0056] In some embodiments, the power adapter 2 can input a voltage of 5V or 20V to the docking station 1 through the first end of the docking station 1 .

[0057] The above steps of the present invention may be executed sequentially, or may be adaptively adjusted according to actual conditions, without limiting the above execution order.

[0058] In some embodiments, the power management method of the docking station 1 may further include: after the terminal device 3 detects that the voltage on the third signal line drops to the first preset value, the MCU 10 starts to output a voltage higher than the first preset value to the third signal line, thereby preventing energy waste.

[0059] The present invention can achieve the above steps by modifying the program without adding a new hardware circuit. The present invention monitors the CC pin voltage change of the Type-C socket and uses the MCU to control the power switching process to achieve Fast Role Swap (FRS), thereby eliminating the need for an additional backup power circuit.

[0060] The present invention realizes power management through software control, does not need to add new hardware circuits, reduces costs, and improves the reliability and miniaturization of equipment.

[0061] Although the present invention is specifically described above in conjunction with the accompanying drawings and examples, it is to be understood that the above description does not limit the present invention in any form. Those skilled in the art can deform and change the present invention as needed without departing from the essential spirit and scope of the present invention, and these deformations and changes all fall within the scope of the present invention.

Claims

1. A power management method for an expansion dock, wherein a first end of the expansion dock is connected to a first end of a power adapter, a second end of the power adapter is connected to a power source, a second end of the expansion dock is connected to a terminal device, a third end of the expansion dock is connected to a peripheral device, the expansion dock comprises an MCU, a first switch, a second switch, and a discharge circuit, a first signal line in the first end of the expansion dock is respectively connected to the first switch and the MCU, a second signal line in the first end of the expansion dock is connected to the MCU, a third signal line in the second end of the expansion dock is respectively connected to the second switch, the MCU, and the discharge circuit, a fourth signal line in the second end of the expansion dock is connected to the MCU, the MCU is connected to the discharge circuit, and the first switch is connected to the second switch, characterized in that The method comprises the following steps: The MCU monitors a voltage change of the first signal line or the second signal line in the first end of the power adapter; When the MCU detects that the voltage of the first signal line or the second signal line in the first end of the power adapter changes from high to low and meets the disconnection feature, it is determined as a pull-out event; The MCU sends a low level pulse to the fourth signal line in the second end of the docking station to initiate an FRS request to the terminal device; The MCU turns off the second switch and starts the discharge circuit, where the discharge circuit is used to reduce the voltage on the third signal line; When the terminal device detects that the voltage on the third signal line drops to a first preset value, it starts to output a voltage higher than the first preset value to the third signal line; When the first end of the docking station is disconnected from the first end of the power adapter, or the second end of the power adapter is disconnected from the power source, the voltage on the first signal line starts to drop; When the MCU detects that the voltage on the first signal line drops to be equal to or close to the voltage on the three signal lines, the first switch is turned off and the second switch is turned on, so that the terminal device supplies power to the expansion dock.

2. The method according to claim 1, characterized in that The first preset value is 4.75V.

3. The method according to claim 2, characterized in that The terminal device starts to output a voltage of 5V to the third signal line when monitoring that the voltage on the third signal line drops to 4.75V.

4. The method according to claim 1, characterized in that: The first signal line is a VBUS_PD signal line, the second signal line is a CC_PD signal line, the third signal line is a VBUS_UFP signal line, and the fourth signal line is a CC_UFP signal line.

5. The method according to claim 3, characterized in that: The power adapter inputs a voltage of 5V or 20V to the expansion dock through the first end of the expansion dock.

6. The method according to claim 3, characterized in that The voltage on the third signal line drops to 4.75V and rises from 4.75V to 5V in 200 microseconds.

7. The method according to claim 1, characterized in that The method further includes: after the terminal device detects that the voltage on the third signal line drops to a first preset value, the MCU starts to output a voltage higher than the first preset value to the third signal line, and turns off the discharge circuit.

8. The method according to claim 1, characterized in that: The expansion dock is an expansion dock with a Type-C interface, a first end of the expansion dock is a first Type-C interface, and a second end of the expansion dock is a second Type-C interface.

9. A docking station, characterized in that: The first end of the expansion dock is connected to the first end of the power adapter, the second end of the power adapter is connected to the power supply, the second end of the expansion dock is connected to the terminal device, the third end of the expansion dock is connected to the peripheral device, the expansion dock includes an MCU, a first switch, a second switch, and a discharge circuit, the first signal line in the first end of the expansion dock is respectively connected to the first switch and the MCU, the second signal line in the first end of the expansion dock is connected to the MCU, the third signal line in the second end of the expansion dock is respectively connected to the second switch, the MCU and the discharge circuit, the fourth signal line in the second end of the expansion dock is connected to the MCU, the MCU is connected to the discharge circuit, the first switch is connected to the second switch, and the expansion dock is used to execute the method described in any one of claims 1 to 8.

10. A control system, characterized in that: The control system includes a power supply, a power adapter, a terminal device, a peripheral device, and the expansion dock as claimed in claim 9.

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