Mainboard and server

Abstract

The utility model provides a mainboard and a server. The mainboard comprises a south bridge chip PCH and an RTC power supply circuit. The RTC power supply circuit is used for supplying power to the south bridge chip PCH; the RTC power supply circuit comprises a main power supply circuit, a first standby power supply circuit and a second standby power supply circuit. The first standby power supply circuit comprises a first standby power supply and a first standby power supply charging and discharging circuit. The input end of the first standby power supply charging and discharging circuit is coupled with the main power supply through a first terminal, and the output end is coupled with the south bridge chip PCH through a second terminal; the second standby power supply circuit comprises a second standby power supply and a second standby power supply circuit; the input end of the second standby power supply circuit is coupled with a second standby power supply, and the output end of the second standby power supply circuit is coupled with the south bridge chip PCH; the second standby power supply circuit comprises a switching circuit; a control terminal of the switching circuit is coupled to the second terminal. The system is suitable for outdoor and indoor service, and even power supply for equipment which is used for a long time.

Description

Technical Field

[0001] The present invention relates to the technical field of clock chip power supply, and in particular to a mainboard and a server. Background Art

[0002] Computing devices, such as servers, require an additional power supply to ensure the normal operation of the real-time clock (RTC) in the south bridge chip (Platform Controller Hub, PCH) after the system loses power. Otherwise, the Basic Input Output System (BIOS) settings will be lost after the power is turned off, and the BIOS needs to be reconfigured when it is powered on again.

[0003] For safety reasons, when the system loses power, the traditional way is to switch to the backup power supply to power the RTC. The backup power supply usually selects a single power supply of a certain type of power supply. However, after the backup power supply is exhausted, if the main power supply is not restored, the BIOS settings will be lost. Utility Model Content

[0004] In view of the problem in the prior art that when the main power supply fails, a single backup power supply is used to power the south bridge chip PCH, which cannot meet the requirements of some devices being inconvenient to disassemble and replace the backup power supply, and the BIOS settings being lost due to the short continuous power supply time of the backup power supply, the present embodiment provides a motherboard and a server.

[0005] In the first aspect, an embodiment of the present application provides a mainboard, including a south bridge chip PCH and an RTC power supply circuit, wherein the RTC power supply circuit is coupled to the south bridge chip PCH for supplying power to the south bridge chip PCH; the RTC power supply circuit includes: a main power supply circuit, whose input end is coupled to the main power supply through a first terminal, and whose output end is coupled to the south bridge chip PCH through a second terminal; a first backup power supply circuit; the first backup power supply circuit includes a first backup power supply and a first backup power supply charge and discharge circuit; the first end of the first backup power supply charge and discharge circuit is coupled to the main power supply through the first terminal, and the second end of the first backup power supply charge and discharge circuit is coupled to the south bridge chip PCH through the second terminal; the third end of the first backup power supply charge and discharge circuit is coupled to the first backup power supply; the second backup power supply circuit includes a second backup power supply and a second backup power supply circuit; the input end of the second backup power supply circuit is coupled to the second backup power supply, and the output end of the second backup power supply circuit is coupled to the south bridge chip PCH; the second backup power supply circuit includes a switch circuit; the control end of the switch circuit is coupled to the second terminal.

[0006] In the RTC power supply circuit in the motherboard, the voltage difference between the first terminal and the second terminal is used to determine whether the main power supply or the first backup power supply is used to supply power to the south bridge chip PCH, and the voltage of the second terminal is used to determine whether the second backup power supply is turned on to supply power to the south bridge chip PCH. In this way, automatic switching among the main power supply, the first backup power supply and the second backup power supply can be achieved.

[0007] In one possible implementation, based on the voltages of the first terminal and the second terminal, the main power supply circuit or the first backup power supply charging and discharging circuit is selected to supply power to the south bridge chip PCH; and when the main power supply circuit supplies power to the south bridge chip PCH, the first backup power supply is charged by the first backup power supply charging and discharging circuit; when the voltage of the second terminal is lower than a preset threshold, the switch circuit is turned on to turn on the second backup power supply circuit, and the south bridge chip PCH is supplied with power by the second backup power supply circuit.

[0008] In a possible implementation, based on the voltages of the first terminal and the second terminal, the main power supply circuit or the first backup power supply charge and discharge circuit is selected to supply power to the south bridge chip PCH, including: when the voltage of the first terminal is less than the voltage of the second terminal, the main power supply circuit is disconnected, and the first backup power supply charge and discharge circuit is turned on; the first backup power supply charge and discharge circuit supplies power to the south bridge chip PCH; when the voltage of the first terminal is not less than the voltage of the second terminal, the main power supply circuit is turned on, and the first backup power supply charge and discharge circuit is disconnected; the main power supply circuit supplies power to the south bridge chip PCH.

[0009] In a possible implementation, when the voltage of the second terminal is lower than a preset threshold, the switch circuit is turned off to disconnect the second backup power supply circuit.

[0010] In the RTC power supply circuit on the mainboard, the preset threshold is the closing threshold of the switch circuit, and the circuit switch is closed or opened by automatically controlling the voltage of the second terminal.

[0011] In one possible implementation, the first backup power supply circuit includes: a first backup power supply charging circuit; the first backup power supply charging circuit includes: a first resistor (R1), whose first end is coupled to the first backup power supply; a first diode (D11), whose anode is coupled to the first terminal, and whose cathode is coupled to the second end of the first resistor (R1); a first backup power supply discharging circuit; the first backup power supply discharging circuit includes: a first resistor (R1), whose first end is coupled to the first backup power supply; a second diode (D12), whose anode is coupled to the second end of the first resistor (R1), and whose cathode is coupled to the second terminal.

[0012] In a possible implementation, the switch tube is a metal oxide semiconductor field effect tube.

[0013] In a possible implementation, the main power supply circuit includes at least one diode; when the number of diodes in the main power supply circuit is n, the first backup power supply charging and discharging circuit includes at least n+1 series diodes; the n diodes included in the main power supply circuit are connected in series in sequence, and each of the n diodes connected in series in sequence has an anode coupled to the cathode of the previous diode, and a cathode coupled to the anode of the next diode; wherein the first diode close to the first terminal of the n diodes has an anode coupled to the first terminal; the nth diode close to the second terminal of the n diodes has a cathode coupled to the second terminal; the first backup power supply charging and discharging circuit includes at least n+1 series diodes; the n diodes included in the main power supply circuit are connected in series in sequence, and the anode of each diode in the n diodes connected in series in sequence is coupled to the cathode of the previous diode, and the cathode of each diode in the n diodes connected in series is coupled to the anode of the next diode; wherein the first diode close to the first terminal of the n diodes has an anode coupled to the first terminal; the cathode of the nth diode close to the second terminal of the n diodes is coupled to the second terminal; The power supply circuit includes n+1 diodes connected in series in sequence, and each of the n+1 diodes in series has an anode coupled to the cathode of the previous diode, and a cathode coupled to the anode of the next diode; wherein the first diode close to the first terminal among the n+1 diodes has an anode coupled to the first terminal; the n+1th diode close to the second terminal among the n+1 diodes has a cathode coupled to the second terminal; the sum of the conduction voltage drops of the n diodes included in the main power supply circuit is lower than the sum of the conduction voltage drops of the n+1 diodes included in the first backup power supply circuit; and n is a natural number greater than or equal to 1.

[0014] In a possible implementation, the main power supply provides low voltage direct current; the first backup power supply is a super capacitor, and the second backup power supply is a button battery. The supply voltage of the main power supply is greater than the supply voltages of the first backup power supply and the second backup power supply.

[0015] In the RTC power supply circuit on the mainboard, a plurality of diodes are arranged to realize automatic switching between the main power supply circuit and the backup power supply circuit, and the structure is simple and easy to realize.

[0016] In a second aspect, an embodiment of the present application provides a server, including a mainboard power supply and the mainboard as described in the first aspect. The mainboard is powered by the mainboard power supply, and when the mainboard power supply is powered off, the first backup power supply circuit or the second backup power supply circuit in the RTC power supply circuit on the mainboard supplies power to the south bridge chip PCH in the mainboard.

[0017] For the specific description of the second aspect in the embodiment of the present application, reference may be made to the description of the mainboard in the first aspect and its various implementations. Also, for the beneficial effects of the second aspect and its various implementations, reference may be made to the analysis of the beneficial effects in the first aspect and its various implementations, which will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of a mainboard;

[0019] Figure 2 A schematic diagram of the structure of using a button battery to power the south bridge chip PCH in the prior art;

[0020] Figure 3 A schematic diagram of the structure of a mainboard provided in an embodiment of the present application;

[0021] Figure 4 A schematic diagram of the structure of a mainboard provided in an embodiment of the present application;

[0022] Figure 5 A schematic diagram of a topological structure of a mainboard provided in an embodiment of the present application;

[0023] Figure 6 A schematic diagram of a circuit topology structure of another mainboard provided in an embodiment of the present application;

[0024] Figure 7 A server 700 is provided in an embodiment of the present application. DETAILED DESCRIPTION

[0025] The terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and need not be used to describe a specific order or sequential order. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, which is only to describe the distinction mode adopted by the objects of the same attributes when describing in the embodiments of the present application. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, so that the process, method, system, product or equipment comprising a series of units need not be limited to those units, but may include other units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0026] The term "and / or" in this article is a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The symbol " / " in this article indicates that the associated objects are in an or relationship, for example, A / B means A or B.

[0027] The terms "first" and "second" in the specification and claims herein are used to distinguish different objects rather than to describe a specific order of the objects. For example, a first response message and a second response message are used to distinguish different response messages rather than to describe a specific order of the response messages.

[0028] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0029] In the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more than two. For example, multiple processing units refer to two or more processing units, etc.; multiple elements refer to two or more elements, etc.

[0030] To facilitate understanding of the embodiments of the present application, the terms involved in the embodiments of the present application are first introduced.

[0031] Server: A high-performance computer that runs corresponding application software in a network environment, provides shared information resources and various services to online users, and provides various shared services and other applications to terminal users. The server may include a central processing unit, memory, hard disk, various buses, etc., and has high-speed computing capabilities, long-term reliability, and strong external data throughput capabilities.

[0032] The motherboard, also known as the mainboard, system board, or motherboard, is used to connect the various components in the server. The motherboard is used to transmit various electronic signals and perform data calculation and processing.

[0033] Basic input output system (BIOS) chip: It carries the computer's basic input and output programs, the self-test program after powering on, and the system startup program. BIOS is the computer's firmware, specifically a set of programs fixed on a read-only memory (ROM) chip on the computer motherboard.

[0034] Central processing unit (CPU): As the computing and control core of the information processing system, it is the execution unit for information processing and program running.

[0035] The bridge chip (platform controller hub, referred to as PCH), can also be called the south bridge chip. The south bridge chip is used to process low-speed signals and is connected to the CPU through communication circuits.

[0036] Real-time clock (RTC) is a key component in computer systems that provides real-time time and date information. It has important functions such as persistent storage, system startup clock, and timing functions.

[0037] Power supply unit (PSU): also known as a power supply, is a power supply that converts electrical energy (different from a battery-powered power supply) and is used to convert standard AC power into low-voltage stable DC power, and provide DC power to other devices.

[0038] Electronic devices, such as servers, require an additional power supply to ensure the normal operation of the real-time clock RTC in the south bridge chip PCH after the system loses power, so as to provide the BIOS with clock signals and some setting information.

[0039] Figure 1 A schematic diagram of the structure of a motherboard is shown in FIG. Figure 1 As shown, the motherboard 110 includes a CPU 10, a BIOS program 20 running in the CPU 10, a south bridge chip PCH 30, a PSU 40, and a memory stick 50. The CPU 10 communicates and transmits data with the memory stick 50 through a memory controller, and can also read data from the memory stick 50. The PSU 40 can be used as a motherboard power supply to power the south bridge chip 30 and the CPU 10 after passing through a voltage conversion device. The RTC is located in the south bridge chip PCH (not shown in the figure), and the RTC can be powered by powering the south bridge chip PCH.

[0040] When the server starts, some BIOS setting information such as the startup parameters for startup operation is stored in the complementary metal oxide semiconductor (CMOS) in the south bridge chip PCH30. Each time the computer is turned on, the south bridge chip PCH30 reads the BIOS setting information from the CMOS to execute the BIOS program 20 to implement hardware detection, hardware initialization, resource allocation, operating system (OS) startup boot, etc. CMOS is a volatile memory that requires uninterrupted power supply to maintain data. And when the server starts, the BIOS needs to provide a clock signal to the CPU or other control chips on the main board through the RTC in the PCH, so the south bridge chip PCH30 needs to be continuously powered on.

[0041] In order to continuously supply power to the south bridge chip PCH when the main power supply fails, the prior art uses a button battery as a backup power supply to supply power to the south bridge chip PCH when the main power supply fails. Figure 2 The schematic diagram of the structure of using a button battery to power the south bridge chip PCH in the prior art is as follows: Figure 2 The power supply circuit includes a mainboard power supply 21, a button battery 22, a diode D1 and a diode D2. The mainboard power supply 21 and the button battery 22 supply power to the south bridge chip PCH23 through the diode D1 and the diode D2 respectively.

[0042] The mainboard power supply 21 is the main power supply of the electronic device, and provides the power supply voltage for the south bridge chip PCH23 after the mainboard power supply 21 is powered on. The prior art is a backup power supply for the south bridge chip PCH23, which provides the power supply voltage when the main power supply is powered off. The button battery 22 serves as the backup power supply for the south bridge chip PCH23. When the mainboard power supply 21 is powered off, it automatically switches to the button battery 22 to power the south bridge chip PCH. When both the mainboard power supply 21 and the button battery 22 can supply power, the mainboard power supply 21 is selected for power supply because the voltage of the mainboard power supply 21 is higher than the voltage provided by the button battery 22. The mainboard power supply 21 can be a 12V voltage output by the PSU on the mainboard (the PSU can convert the connected 220V input voltage into 12V DC), which is obtained by a voltage conversion chip. For example, the voltage conversion chip is a DC-DC voltage converter, which converts the 12V voltage output by the PSU into 3.3V DC.

[0043] Although the shelf life of a button battery can reach 10 years, traditional button batteries cannot be recharged and are constantly discharged during use. The actual usable power is often exhausted in 2-3 years. If the south bridge chip PCH is not powered after the button battery is exhausted, the PCH clock signal will be lost. This requires replacing the button battery. Please continue to read Figure 1 , the server's motherboard (including the components installed on the motherboard) is installed in the server's chassis. If the power supply for the motherboard needs to be replaced, according to the existing settings, the chassis needs to be opened for replacement. This is not applicable in some usage scenarios where the server shell is not convenient to disassemble. For example, most of the current servers are placed in a cabinet, and a cabinet can hold more than a dozen servers. If the power supply for each server is replaced, the backplane of each server needs to be disassembled, which will be a lot of work.

[0044] In order to solve the problems existing in using button batteries as backup power sources, an embodiment of the present application provides a motherboard that automatically switches to power a south bridge chip PCH using a main power supply and at least two backup power sources. Figure 3 A schematic diagram of the structure of a mainboard provided in an embodiment of the present application is shown in FIG. Figure 3 As shown. The motherboard 300 includes a main power supply circuit 31, a backup power supply circuit 32, and a south bridge chip PCH33. The main power supply 35 supplies power to the main power supply circuit 31 and part of the backup power supply circuit 32. The backup power supply circuit 32 includes at least two backup power supply circuits. When the main power supply 35 loses power, the voltage of point A and point B is automatically switched to the backup power supply circuit 32 to supply power to the south bridge chip PCH33.

[0045] At least two backup power circuits included in the backup power circuit 32 are automatically switched based on the voltages at point A (first terminal) and point B (second terminal) to continuously supply power to the south bridge chip PCH33.

[0046] Figure 4 A schematic diagram of the structure of a mainboard provided in an embodiment of the present application is shown in FIG. Figure 4 The mainboard 400 includes an RTC power supply circuit 410 and a south bridge chip PCH 60. The RTC power supply circuit 410 includes a main power supply circuit 30, a first backup power supply circuit 40, and a second backup power supply circuit 50.

[0047] The input end of the main power supply circuit 30 is coupled to the main power supply 20 via point A, and the output end is coupled to the south bridge chip PCH60 via point B; the RTC set in the south bridge chip PCH60 is used to provide a clock signal for the BIOS.

[0048] The first backup power circuit 40 is coupled between point A and point B, with its input end coupled to point A and its output end coupled to point B. The first backup power circuit 40 includes a first backup power charge and discharge circuit 46 and a first backup power source 44 , and the first backup power charge and discharge circuit 46 includes a first backup power charge circuit 43 and a first backup power discharge circuit 45 .

[0049] The first end of the first backup power supply charge and discharge circuit 46 is coupled to the main power supply 20 through point A, and the second end of the first backup power supply charge and discharge circuit 46 is coupled to the south bridge chip PCH60 through point B; the third end of the first backup power supply charge and discharge circuit 46 is coupled to the first backup power supply 44.

[0050] The first backup power charging circuit 43 includes a first resistor R1 and a first diode D11. The first end of the first resistor R1 is coupled to the first backup power source 44, and the second end is coupled to the cathode of the first diode D11; the anode of the first diode D11 is coupled to point A. The first diode D11 is used to prevent the discharge current of the first backup power source 44 from flowing back to the main power source 20.

[0051] The first backup power supply discharge circuit 45 includes a first resistor R1 and a second diode D12. Its input end is coupled to the first backup power supply 44, and its output end is coupled to point B. The first end of the first resistor R1 is coupled to the first backup power supply 44, and the second end is coupled to the anode of the second diode D12; the cathode of the second diode D12 is coupled to point B.

[0052] The second backup power circuit 50 includes a second backup power supply 52 and a second backup power supply circuit 53. Its input end is coupled to point B, and its output end is coupled to the south bridge chip PCH60. The second backup power circuit 50 includes a switch circuit 51; the control end of the switch circuit 51 is coupled to point B.

[0053] The main power supply circuit 30 includes at least one diode. It should be noted that when the main power supply circuit 30 includes n diodes, the first backup power supply circuit 40 includes at least n+1 diodes.

[0054] The main power supply circuit 30 includes n diodes connected in series in sequence. The anode of each of the n diodes connected in series in sequence is coupled to the cathode of the previous diode, and the cathode of each diode is coupled to the anode of the next diode.

[0055] The anode of the first diode close to point A among the n diodes is coupled to point A; the cathode of the nth diode close to point B among the n diodes is coupled to point B.

[0056] The first backup power circuit 40 includes n+1 diodes connected in series. The anode of each of the n+1 diodes connected in series is coupled to the cathode of the previous diode, and the cathode of each diode is coupled to the anode of the next diode.

[0057] The anode of the first diode close to point A among the n+1 diodes is coupled to point A; the cathode of the n+1th diode close to point B among the n+1 diodes is coupled to point B.

[0058] The sum of the conduction voltage drops of the n diodes included in the main power supply circuit 30 is lower than the sum of the conduction voltage drops of the n+1 diodes included in the first backup power supply circuit 40. Where n is a natural number greater than or equal to 1.

[0059] Figure 4 As shown, the main power supply circuit 30 includes a fourth diode D14, and the first backup power supply circuit 40 includes two diodes, namely the first diode D11 and the second diode D12, to ensure that when the main power supply 20 is powered on, the diode voltage drop of the main power supply 20 through the fourth diode D14 is less than the sum of the diode voltage drops of the main power supply 20 through the first diode D11 and the second diode D12. Therefore, when the main power supply 20 is powered on, the south bridge chip PCH60 is powered through the fourth diode D14. In other words, when the main power supply 20 is powered on, the main power supply 20 supplies power to the south bridge chip PCH60 through the main power supply circuit 30. At this time, the voltage at point B is lower than the voltage at point A.

[0060] When the main power supply 20 is powered on, because the voltage at point B is lower than the voltage at point A, the fourth diode D14 is turned on, and the main power supply circuit 30 supplies power to the south bridge chip PCH60 through the fourth diode D14; the second diode D12 is turned off, and the main power supply 20 does not supply power to the south bridge chip PCH60 through the first diode D11 and the second diode D12. At the same time, because the first diode D11 is forward-conducted, the main power supply 20 charges the first backup power supply 44 through the first diode D11.

[0061] When the main power supply 20 is powered on, the voltage at point B is the voltage at point A minus the diode conduction voltage drop of a diode (the fourth diode D14).

[0062] When the main power supply 20 loses power, the voltage at point A is 0V, the first diode D11 is turned off, and the fourth diode D14 is turned off. At this time, since the first backup power supply 44 has stored a certain amount of electric energy, the voltage at the cathode of the first diode D11 is higher than the voltage at point B, and the second diode D12 is forwardly turned on. The first backup power supply 44 supplies power to the south bridge chip PCH60 through the first backup power supply discharge circuit 45.

[0063] When the main power supply 20 loses power, the voltage at point B is the voltage provided by the first backup power supply minus the diode voltage drop of the diode (second diode D12), and the voltage at point B is greater than the voltage at point A. When the main power supply 20 loses power, the first backup power supply 44 supplies power to the south bridge chip PCH60. As the first backup power supply 44 continues to supply power, the output voltage of the first backup power supply 44 decreases, and the voltage at point B also decreases. When the voltage at point B decreases to a preset threshold, the south bridge chip PCH38 is powered by the second backup power supply circuit 50. The preset threshold is a voltage threshold that turns on the switch circuit 51.

[0064] In a possible implementation, when the first backup power supply 44 supplies power to the south bridge chip PCH60, the main power supply 20 is powered on again, the voltage at point A is greater than the voltage at point B, the main power supply circuit 30 is turned on, and the main power supply circuit 30 continues to supply power to the south bridge chip PCH60. In other words, the present application will automatically switch to the backup power supply only when the main power supply is unavailable, and automatically switch to the main power supply after the main power supply is powered on.

[0065] The main power supply 20 charges the first backup power supply 44 until the first backup power supply 44 reaches the rated power and then stops automatically. The rated power of the first backup power supply 44 is determined by the type of the selected first backup power supply. Further, the type of the first backup power supply can be determined according to the power supply voltage range of the south bridge chip PCH60.

[0066] It should be noted that the diodes provided in the embodiments of the present application may be diodes of a uniform model so that the parameters of the circuit can be easily adjusted.

[0067] When the main power supply 20 charges the first backup power supply 44, the first resistor R1 plays a role of current limiting, so that the charging current of the main power supply 20 for the first backup power supply 44 is less than the maximum charging current of the first backup power supply 44. For example, the resistance value of the first resistor R1 is determined according to the current size of the main power supply 20 charging the first backup power supply 44.

[0068] The main power supply circuit 30, the first backup power supply charging circuit 43 and the first backup power supply discharging circuit 45 provided in the embodiment of the present application are only an implementation circuit of the multi-power switching RTC power supply circuit. The circuit that can realize automatic switching according to the changes in the output voltage of the main power supply and the first backup power supply also belongs to the protection scope of the embodiment of the present application, and the present application is not limited to this.

[0069] The RTC power supply circuit with multiple power supply switching provided in the embodiment of the present application can be applied to electronic devices powered by a main power supply and a backup power supply, wherein the main power supply can be a mainboard power supply of the electronic device, and the mainboard power supply is a power supply that provides voltage for components on the mainboard, such as a CPU, a south bridge chip PCH, and a memory stick, etc. The first backup power supply can be a power supply that can be charged and discharged, such as a capacitor or a rechargeable battery.

[0070] In one possible implementation, a power source that can be considered as a backup power source is used to obtain a longer operating time in the backup mode, such as a supercapacitor. The first backup power source 32 can be a supercapacitor, which can be implemented with any suitable capacitor. For example, the capacitor has a higher capacitance and a lower effective series resistance to provide a suitable current for the south bridge chip PCH60 for a longer duration. A supercapacitor is a power source with special properties between a traditional capacitor and a battery, which relies on double-layer and redox pseudocapacitor charge to store electrical energy. A supercapacitor is a commonly used backup power source.

[0071] Specifically, the supercapacitor may be a capacitor with a capacity of several hundred millifarads, and a plurality of supercapacitors connected in parallel are used as the first backup power source 44. When the main power supply is powered off, the supercapacitor is turned on to supply power to the south bridge chip PCH60. When the main power supply is powered on, the charging circuit from the main power supply to the supercapacitor is turned on to charge the supercapacitor.

[0072] In another possible implementation, the first backup power source 44 may also be a rechargeable battery, and the rechargeable battery may be used as a battery module formed by connecting a plurality of battery cells in series and / or in parallel.

[0073] The second backup power source may be a button battery.

[0074] In a possible implementation, the button battery is configured to conduct the second backup power circuit 50 between the button battery and the south bridge chip PCH60 when the super capacitor is about to be exhausted, that is, the output voltage of the super capacitor drops to a preset threshold value, so as to power the south bridge chip PCH60 when both the main power supply and the super capacitor cannot supply power. The embodiment of the present application first uses the main power supply to power the south bridge chip PCH, and charges the super capacitor at the same time, uses the super capacitor to power the south bridge chip PCH60 after the mainboard power is powered off, and uses the button battery to power the south bridge chip PCH60 when the super capacitor is about to be exhausted, which prolongs the use time compared to the traditional use of button batteries alone. When the outdoor product is powered off and deactivated or powered off for maintenance, the first backup power supply and the second backup power supply can be used to provide power supply voltage for the south bridge chip PCH60, so as to keep the BIOS settings from being lost, and the BIOS does not need to be reconfigured after the system is powered on. At the same time, because the first backup power supply is charged during the system power-on period, it is not necessary to disassemble the casing and replace the second backup power supply during a longer service life. Therefore, the RTC power supply circuit provided in the embodiment of the present application can provide power to the south bridge chip PCH60 for a long time, so that the BIOS settings can maintain information loss for a long time, for example, within 10 years.

[0075] In a possible implementation, the first backup power supply charging circuit may also be incorporated with a circuit for controlling the charging current of the supercapacitor to ensure that it does not charge too fast. For example, the first resistor R1 may be replaced with a circuit for controlling the charging current of the supercapacitor to adjust the charging current.

[0076] Please continue to see Figure 4 The second backup power circuit 50 includes a second resistor R2, a third diode D13, a switch circuit 51 and a third resistor R3. The first end of the second resistor R2 is coupled to the ground, and the second end is coupled to the control end of the switch circuit 51. The cathode of the third diode D13 is coupled to the south bridge chip PCH60, the anode of the third diode D13 is coupled to the second end of the switch circuit 51, the control end of the switch circuit 51 is coupled between the second end of the second resistor R2 and the B node, and the third end of the switch circuit 51 is coupled to the first end of the third resistor (R3). The second end of the third resistor (R3) is coupled to the second backup power 52.

[0077] The switch circuit 51 controls the second backup power supply discharge circuit 50 to be turned on or off. When the switch circuit 51 is turned off, the second backup power supply circuit 50 is disconnected, and the main power supply 20 or the first backup power supply 44 supplies power to the south bridge chip PCH. When the switch circuit 51 is turned on, the second backup power supply circuit 50 is turned on, and a stable power supply voltage is provided to the south bridge chip PCH within a certain range of the voltage provided by the second backup power supply 52.

[0078] When the main power supply 20 loses power and the power of the first backup power supply 44 is about to be exhausted, specifically, the voltage of the first backup power supply 44 is lower than the diode voltage drop of the second diode D12, the second diode D12 is cut off, and point B is a low level. In other words, the conduction condition of the circuit switch 51 is met, the circuit switch 51 is turned on, and power is supplied to the south bridge chip PCH through the second backup power supply circuit 50.

[0079] It should be noted that the high level at point B is a voltage value not lower than a preset threshold value of the switch circuit 51 , and the low level at point B is a voltage value lower than a preset threshold value of the switch circuit 39 .

[0080] In a possible implementation, the circuit switch 51 includes a first switch tube Q1 and a second switch tube Q2.

[0081] It can be understood that the switch tubes Q1 and Q2 are controllable switch tubes. The types of the switch tubes Q1 and Q2 can be any of the following: Metal-Oxide-Semiconductor Field-EffectTransistor (MOSFET), Insulated Gate Bipolar Transistor (IGBT), Gallium Nitride Transistor (GaN Transistor), Silicon Carbide Transistor (SiC Transistor), triode, thyristor, etc. Among them, the switch tube Q1 can be an N-type MOSFET (NMOS for short) or a P-type MOSFET (PMOS for short).

[0082] In the present embodiment, the switch tubes Q1 and Q2 are PMOS tubes. Figure 4 The topology of the multi-power switching RTC power supply circuit shown is described.

[0083] It should be noted that when the switch tube Q1 is a PMOS tube, the first end of the switch tube Q1 is the gate electrode (that is, the G electrode) of the PMOS tube; the second end of the switch tube Q1 is the source electrode (that is, the S electrode) of the PMOS tube; and the third end of the switch tube Q1 is the drain electrode (that is, the D electrode) of the PMOS tube. When the switch tube Q2 is a PMOS tube, the first end of the switch tube Q2 is the gate electrode of the PMOS tube; the second end of the switch tube Q2 is the source electrode of the PMOS tube; and the third end of the switch tube Q2 is the drain electrode of the PMOS tube.

[0084] In a possible implementation, the switch circuit 51 includes a first PMOS transistor Q1 and a second PMOS transistor Q2. Figure 4As shown, the first end of the first PMOS tube Q1 and the first end of the second PMOS tube Q2 are commonly coupled between the second end of the second resistor R2 and point B. The second end of the first PMOS tube Q1 is coupled to the first end of the third resistor R3, and the third end of the first PMOS tube Q1 is coupled to the third end of the second PMOS tube Q2. The second end of the second PMOS tube Q2 is coupled to the anode of the third diode D13. Because of the parasitic diodes inside the first PMOS tube Q1 and the second PMOS tube Q2, when the voltage difference between the main power supply 31 and the second backup power supply 33 is small or even equal, the gate of the first PMOS tube Q1 and the gate of the second PMOS tube Q2 are connected in series, and the drains are coupled at the same end, so as to prevent the current of the main power supply from flowing to the second backup power supply 52 through the first PMOS tube Q1 and the second PMOS tube Q2.

[0085] It should be noted that the conduction condition of the PMOS tube is Ug-Us<0, and |Ug-Us|>|Ugs(th)|, where Ug is the gate voltage of the PMOS tube, Us is the source voltage of the PMOS tube, Ugs is the gate-source voltage of the PMOS tube, and Ugs(th) is the threshold voltage of the PMOS tube; that is, when the absolute value of the difference between the gate voltage and the source voltage of the PMOS tube is greater than its threshold voltage, the PMOS tube is turned on.

[0086] When the main power supply 20 is powered on, the voltage at point B is at a high level (the high level here means that the voltage at point B is higher than the voltage at the gate of the PMOS tube, that is, Ug-Us>0); when the main power supply 20 is powered off and the first backup power supply 44 supplies power to the south bridge chip PCH through the first backup power supply circuit 43, the voltage at point B is still at a high level; when the main power supply 20 is powered off and the first backup power supply 44 is about to be exhausted, the voltage at point B flips to a low level (the low level here means that the voltage at point B is lower than the voltage at the gate of the PMOS tube, that is, Ug-Us<0, and it is guaranteed that |Ug-Us|>|Ugs(th)|).

[0087] When the voltage at point B is low, the first ends of the first PMOS tube Q1 and the second PMOS tube Q2 are low, the first PMOS tube Q1 and the second PMOS tube Q2 are turned on, and the second backup power supply 52 supplies power to the south bridge chip PCH through the third diode D13. When the voltage at point B is high, the first ends of the first PMOS tube Q1 and the second PMOS tube Q2 are high, the first PMOS tube Q1 and the second PMOS tube Q2 are turned off, and the second backup power supply 52 cannot supply power to the south bridge chip PCH through the third diode D13.

[0088] In a possible implementation, the switch circuit 51 includes only the first switch tube Q1. Take the switch tube Q1 as a PMOS tube as an example for explanation. The first end of the first PMOS tube Q1 is coupled between the second resistor R2 and point B. The second end of the first PMOS tube Q1 is coupled to the first end of the third resistor R3, and the third end of the first PMOS tube Q1 is coupled to the anode of the third diode D13. The second end of the third resistor R3 is coupled to the second backup power supply 52. ​​The third resistor R3 is used to limit the power supply current when the second backup power supply 52 supplies power to the south bridge chip PCH.

[0089] In a possible implementation, the circuit switch 51 may be a switch tube and a diode connected in series. It should be noted that any circuit that can implement a switch function is applicable to the embodiment of the present application.

[0090] In one possible implementation, when the second backup power supply 52 supplies power to the south bridge chip PCH, the main power supply 20 resumes power, the voltage at point B is pulled up, and the first terminal voltages of the first PMOS tube Q1 and the second PMOS tube Q2 also become high level and are cut off, and then the second backup power supply circuit 50 is disconnected.

[0091] The multi-power switching RTC power supply circuit also includes a capacitor C11. The capacitor C11 is coupled in parallel to the common output terminal of the main power supply circuit, the first backup power supply circuit and the second backup power supply circuit, and is used to output a stable voltage to the south bridge chip PCH.

[0092] The embodiment of the present application uses simple components to build circuits, thereby achieving low cost.

[0093] Figure 5 A schematic diagram of a topological structure of a mainboard provided in an embodiment of the present application, such as Figure 5 As shown. The main power supply 20 is implemented as a mainboard power supply P3V3_AUY, the first backup power supply 44 is implemented as a supercapacitor group composed of a plurality of supercapacitors connected in parallel, and the second backup power supply 52 is implemented as a button battery, which is an optional solution for supplying power to the south bridge chip PCH60. The positive electrode of the supercapacitor group 44 is coupled to the first end of the first resistor R1, and the negative electrode is coupled to the ground. The positive electrode of the button battery 52 is coupled to the second end of the third resistor R3, and the negative electrode is coupled to the ground.

[0094] The button cell may be a lithium battery, or other types, such as a lithium thionyl chloride battery. The supply voltage of the button cell is about 3V.

[0095] It should be noted that the main power supply 20 may be a mainboard power supply P3V3_AUY. Specifically, the mainboard power supply P3V3_AUY may be a 12V voltage output by a PSU on the mainboard (the PSU may convert an input voltage of, for example, 220V into 12V DC) obtained through a voltage conversion chip. For example, the voltage conversion chip is a DC-DC voltage converter, which converts the 12V voltage output by the PSU into 3.3V DC.

[0096] The main power supply circuit 30 includes a fourth diode D14, so that the mainboard power supply P3V3_AUY supplies power to the south bridge chip PCH through the fourth diode D14, and charges the super capacitor bank through the first diode D11. That is, the mainboard power supply P3V3_AUY and the diode D11 act as a charging circuit to charge the super capacitor bank when the voltage output by the system power supply P3V3_AUY is high enough.

[0097] The supercapacitor group 32 includes supercapacitors C21, C22 and C23. The common first end thereof is coupled to the ground, and the second end thereof is coupled to the first end of the first resistor R1. The button battery is coupled to the second end of the third resistor R3. The motherboard power supply P3V3_AUY is coupled to the anode of the first diode D11, and the cathodes of the second diode D12 and the fourth diode D14 are commonly coupled to point B. The capacitor C11 plays a role in stabilizing the output and filtering the power supply voltage of the south bridge chip PCH.

[0098] When the mainboard power supply P3V3_AUY continues to supply power, the fourth diode D14 is forward-conducted, and the mainboard power supply P3V3_AUY supplies power to the south bridge chip PCH through the fourth diode D14; when the mainboard power supply P3V3_AUY loses power, the fourth diode D14 and the first diode D11 are cut off; at this time, the anode voltage of the second diode D12 is the voltage provided by the supercapacitor group 44, the second diode D12 is forward-conducted, and the supercapacitor group 44 supplies power to the south bridge chip PCH through the second diode D12.

[0099] The third diode D13 is a protection diode of the button battery 52, which prevents the current at the power supply end of the south bridge chip PCH from flowing back to the positive electrode of the button battery.

[0100] In a possible implementation, a first resistor R1 having a resistance of 33 ohms is electrically connected between the supercapacitor group 44 and the first diode D11. A second resistor R2 having a resistance of 33 ohms is coupled between the ground and the gates of the first PMOS tube Q1 and the second PMOS tube Q2. A third resistor R3 having a resistance of 1 ohm is coupled between the positive electrode of the button battery 52 and the source electrode of the first PMOS tube Q1. The standard supercapacitor provided in the embodiment of the present application, for example, with a capacitance of 0.33 F or more, is sufficient to enable the south bridge chip PCH to operate for a long time, for example, up to 10 years. The larger the capacitance, the longer the working time; similarly, using a smaller capacitance, for example, the supply current of the first backup power supply can be adjusted by adjusting the first resistor R1, and a lower supply current will allow a longer discharge time.

[0101] In a possible implementation, the duration of the charging current from the mainboard power supply P3V3_AUY to the super capacitor group 44 is adjusted to adjust the time during which the current provided by the super capacitor group 44 is input to the south bridge chip PCH.

[0102] For example, the discharge time of the supercapacitor group is changed by changing the discharge circuit parameters of the supercapacitor group (the capacity of the supercapacitor group, the resistance value of the first resistor R1).

[0103] The anode of the first diode D11 is connected to the mainboard power supply P3V3_AUY, and the cathode of the first diode D11 is connected to the first resistor R1. When the mainboard power supply P3V3_AUY is powered on, the current provided by the system power supply P3V3_AUY is input to the supercapacitor group 44 through the first resistor R1 in a unidirectional manner, so that the supercapacitor group 44 stores electrical energy.

[0104] One end of the first resistor R1 is connected to the cathode of the first diode D11, and the other end of the first resistor R1 is connected to the supercapacitor group 44, which is used to limit the current input to the supercapacitor group 44 by the mainboard power supply P3V3_AUY to prevent the charging current from being too large and causing the supercapacitor group to be broken down.

[0105] One end of the supercapacitor group 44 is connected to the first resistor R1, and the other end of the supercapacitor group 44 is grounded. It is used to receive the current input by the mainboard power supply P3V3_AUY when the mainboard power supply P3V3_AUY is powered on and store it as electrical energy; when the mainboard power supply P3V3_AUY is powered off, it releases the electrical energy to generate the first backup power supply current.

[0106] In a possible implementation, when the supercapacitor group 44 supplies power to the south bridge chip PCH, the mainboard power supply P3V3_AUY is powered on again, at which time the fourth diode D14 is forward-conducted, point B becomes high level, the second diode D12 is turned off, and the mainboard power supply P3V3_AUY continues to supply power to the south bridge chip PCH to achieve automatic switching. When the button battery 52 supplies power to the south bridge chip PCH through the third diode D13, the mainboard power supply P3V3_AUY is powered on again, the fourth diode D14 is forward-conducted, point A becomes high level, and the gates of the first PMOS tube Q1 and the second PMOS tube Q2 become high level and turned off, so as to achieve automatic switching from the button battery to the mainboard power supply P3V3_AUY.

[0107] Figure 6 A schematic diagram of a circuit topology structure of another motherboard provided in an embodiment of the present application is provided. Figure 5 The circuit shown differs in that:

[0108] The second diode D12 and the fourth diode D14 adopt a double diode structure, and the double diode D31 includes the second diode D12 and the fourth diode D14; the first end of the double diode D31 is coupled to the motherboard power supply P3V3_AUY, the second end is coupled to the second end of the first resistor R1, and the third end is coupled to the cathode of the fourth diode D14 and the second diode D12.

[0109] The third diode D13 also adopts a double diode structure. The double diode D33 includes a third diode. The first end of the double diode D33 is coupled to the second end of the switch circuit 51 , and the second end of the double diode D33 is idle. The third end of the double diode D33 is coupled to point B.

[0110] The first diode D11 adopts a dual diode structure, and the dual diode D32 includes the first diode D11. The first end of the dual diode D32 is coupled to the motherboard power supply P3V3_AUY, the second end is idle, and the third end is coupled to the second end of the first resistor R1.

[0111] A double diode refers to a combination of two diodes whose anodes (positive poles) or cathodes (negative poles) are connected together to increase current capacity or change electrical characteristics. The cathodes (or anodes) of these diodes are connected to a point in the circuit by sharing an output pin to form a parallel circuit. There are many double diode packaged chips of different specifications on the market. The RTC power supply circuit of the embodiment of the present application can use a double diode chip to achieve a simple implementation of the circuit.

[0112] Because the structure of the diodes is unified, the circuit can be more convenient to implement. In addition, the first diode D11, the second diode D12, the third diode D13 and the fourth diode D14 use a unified model to make the parameters of the circuit easier to control and make the circuit run more stably.

[0113] See also Figure 5 and Figure 6 , the third end of the dual diode D31 is coupled to point B, and the third end of the dual diode D32 is coupled to point A. The main power supply circuit 30 supplies power to the south bridge chip PCH through the fourth diode D14 in the dual diode D31 and point B. The first backup power supply circuit 45 outputs current from the first backup power supply 44, and supplies power to the south bridge chip PCH through the second diode D12 in the dual diode D31 and point B. The motherboard power supply P3V3_AUY supplies power to the super capacitor group 44 through the first end of the dual diode D32 and the first resistor R1. The second backup power supply circuit 50 supplies power to the south bridge chip PCH through the switch circuit 51 and the third end of the dual diode D33.

[0114] When the double diode is powered through the third terminal, the diode that is turned on is determined by the voltage of the anode and cathode of each of the two parallel diodes. Figure 5 The voltage drop analysis of the diode is the same as in , so it will not be repeated here.

[0115] By adopting an RTC power supply circuit solution in which a supercapacitor and a button battery coexist, the embodiment of the present application can be applied in a usage scenario where the device cannot be disassembled and a long-term continuous power supply in the PCH is required.

[0116] The embodiment of the present application can be applied outdoors. When the outdoor product is powered off or powered off for maintenance, a button battery can be used to keep the BIOS settings from being lost, and the BIOS does not need to be reconfigured next time the system is powered on. At the same time, because of the presence of the supercapacitor, there is no need to remove the shell to replace the battery.

[0117] The embodiments of the present application can be applied indoors. For equipment with an indoor service usage cycle of many years or long-term use, such as equipment with a usage cycle of up to 10 years, the circuit provided by the embodiments of the present application can be used.

[0118] On outdoor 5G supporting edge server equipment, since it is generally a pole-mounted device, it can only be maintained remotely, and the casing cannot be disassembled. Once the power is off for maintenance or power outage, the solution provided by the embodiment of the present application can ensure that the machine will not lose the BIOS settings due to power failure, because the supercapacitor and button battery can continuously supply power and the battery does not need to be replaced within 5-10 years.

[0119] According to a second aspect, an embodiment of the present application provides a server, Figure 7A server 700 provided in an embodiment of the present application is shown, comprising a mainboard 710 and a mainboard power supply 720 as described in the first aspect. The mainboard 710 comprises a south bridge chip 711. When the mainboard power supply 720 is powered on, the server supplies power to the south bridge chip PCH711 through the mainboard power supply 720. When the mainboard power supply 720 is powered off, the south bridge chip PCH711 is powered through the RTC power supply circuit in the mainboard.

[0120] It should be understood that in various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0121] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0122] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0123] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0124] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or an access network device, etc.) to perform all or part of the steps of the method described in each embodiment of the embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk and other media that can store program code.

[0125] The above is only a specific implementation of the embodiments of the present application, but the protection scope of the embodiments of the present application is not limited to this. Any technician familiar with the technical field can easily think of changes or replacements within the technical scope disclosed in the embodiments of the present application, which should be covered within the protection scope of the embodiments of the present application.

Claims

1. A motherboard, characterized in that: include: South bridge chip PCH, An RTC power supply circuit, the RTC power supply circuit is coupled to the south bridge chip PCH and is used to supply power to the south bridge chip PCH; The RTC power supply circuit comprises: A main power supply circuit, an input end of which is coupled to a main power supply via a first terminal, and an output end of which is coupled to a south bridge chip PCH via a second terminal; a first backup power supply circuit; The first backup power supply circuit includes a first backup power supply and a first backup power supply charge-discharge circuit; a first end of the first backup power supply charge-discharge circuit is coupled to the main power supply through the first terminal, and a second end of the backup power supply charge-discharge circuit is coupled to the south bridge chip PCH through the second terminal; a third end of the backup power supply charge-discharge circuit is coupled to the first backup power supply; A second backup power supply circuit; The second backup power supply circuit includes a second backup power supply and a second backup power supply circuit; the input end of the second backup power supply circuit is coupled to the second backup power supply, and the output end of the second backup power supply circuit is coupled to the south bridge chip PCH; the second backup power supply circuit includes a switching circuit; the control end of the switching circuit is coupled to the second terminal.

2. The mainboard according to claim 1, characterized in that: Based on the voltages of the first terminal and the second terminal, a main power supply circuit or a first backup power supply charging and discharging circuit is selected to supply power to the south bridge chip PCH; and when the main power supply circuit supplies power to the south bridge chip PCH, the first backup power supply is charged by the first backup power supply charging and discharging circuit; When the voltage of the second terminal is lower than a preset threshold, the switch circuit is turned on to turn on the second backup power supply circuit, and power is supplied to the south bridge chip PCH through the second backup power supply circuit.

3. The mainboard according to claim 2, characterized in that: The selecting a main power supply circuit or a first backup power supply charging and discharging circuit to supply power to the south bridge chip PCH based on the voltages of the first terminal and the second terminal includes: When the voltage of the first terminal is less than the voltage of the second terminal, the main power supply circuit is disconnected, and the first backup power supply charging and discharging circuit is turned on; the first backup power supply charging and discharging circuit supplies power to the south bridge chip PCH; When the voltage of the first terminal is not less than the voltage of the second terminal, the main power supply circuit is turned on, and the first backup power supply charging and discharging circuit is turned off; the main power supply circuit supplies power to the south bridge chip PCH.

4. The mainboard according to claim 1, characterized in that: Also includes: When the voltage of the second terminal is higher than a preset threshold, the switch circuit is turned off to disconnect the second backup power supply circuit.

5. The mainboard according to any one of claims 1 to 4, characterized in that: The first backup power supply circuit comprises: A first backup power supply charging circuit; The first backup power supply charging circuit comprises: a first resistor (R1), a first end of which is coupled to the first backup power source; a first diode (D11), an anode of which is coupled to the first terminal, and a cathode of which is coupled to the second end of the first resistor (R1); The first standby power supply discharge circuit; The first backup power supply discharge circuit comprises: a first resistor (R1), a first end of which is coupled to the first backup power source; A second diode (D12) has an anode coupled to the second end of the first resistor (R1) and a cathode coupled to the second terminal.

6. The mainboard according to claim 1, characterized in that: The second backup power supply circuit comprises: A second resistor (R2) having a first end coupled to ground; A third diode (D13), a cathode of which is coupled to the south bridge chip PCH, and an anode of which is coupled to the second end of the switch circuit; The switch circuit comprises at least one switch tube, wherein a control end of the switch tube is coupled between the second terminal and the second end of the second resistor (R2); a second end is coupled to the south bridge chip PCH; a third end is coupled to the first end of a third resistor (R3); when the number of the switch tubes is more than one, a plurality of the switch tubes are connected in parallel; A third resistor (R3) has a second end coupled to the second backup power source.

7. The mainboard according to claim 6, characterized in that: The switch tube is a metal oxide semiconductor field effect tube.

8. The mainboard according to claim 1, characterized in that: The main power supply circuit includes at least one diode; When the number of diodes in the main power supply circuit is n, the first backup power supply charging and discharging circuit includes at least n+1 series-connected diodes; The main power supply circuit comprises n diodes connected in series in sequence, and each of the n diodes connected in series in sequence has an anode coupled to the cathode of the previous diode and a cathode coupled to the anode of the next diode; wherein the first diode among the n diodes close to the first terminal has an anode coupled to the first terminal; and the nth diode among the n diodes close to the second terminal has a cathode coupled to the second terminal; The first backup power supply circuit comprises n+1 diodes connected in series in sequence, wherein each of the n+1 diodes connected in series in sequence has an anode coupled to the cathode of a previous diode and a cathode coupled to the anode of a subsequent diode; wherein the first diode among the n+1 diodes close to the first terminal has an anode coupled to the first terminal; and the n+1th diode among the n+1 diodes close to the second terminal has a cathode coupled to the second terminal; The sum of the conduction voltage drops of the n diodes included in the main power supply circuit is lower than the sum of the conduction voltage drops of the n+1 diodes included in the first backup power supply circuit; The n is a natural number greater than or equal to 1.

9. The mainboard according to claim 1, characterized in that: The main power supply provides low voltage direct current; The first backup power source is a supercapacitor, and the second backup power source is a button battery; The supply voltage of the main power supply is greater than the supply voltages of the first backup power supply and the second backup power supply.

10. A server, characterized in that: It comprises a mainboard power supply and a mainboard as described in any one of claims 1 to 9, wherein the mainboard is powered by the mainboard power supply; when the mainboard power supply is powered off, the south bridge chip PCH on the mainboard is powered by the first backup power supply circuit or the second backup power supply circuit in the RTC power supply circuit on the mainboard.

Images