Remote POE power supply device and power supply method

Abstract

The present application relates to the field of remote power supply, and more particularly to a remote POE power supply device and method, comprising a mainboard and a POE switch circuit for connecting to a PD device, wherein the mainboard and the POE switch circuit are connected via a network cable, a POE network card is inserted into the mainboard, and the POE network card supports the WOL function. The mainboard is provided with a step-down circuit, the input end of the step-down circuit is connected to the POE network card, and the output end of the step-down circuit is connected to the power input end of the mainboard. The present application has the effect of realizing remote POE power supply.

Description

Technical Field

[0001] The present application relates to the field of POE power supply, and in particular to a remote POE power supply device and power supply method. Background Art

[0002] POE refers to a technology that, without any changes to the existing Ethernet Category 5 cabling infrastructure, can transmit data signals to IP-based terminals while also providing DC power to such devices. IP-based terminals can include IP phones, network cameras, and other devices. A complete POE system consists of two components: the power supply (PSE) and the powered device (PD). The PSE provides power to Ethernet client devices and manages the entire POE power supply process. The PD, a PSE-powered load, is the client device of the POE system, such as the aforementioned IP phones and network cameras. Based on the IEEE 802.3af or IEEE 802.3at standards, the PSE and PD establish information about the PD's connection status, device type, and functional level, and use this information to provide power to the PD.

[0003] Common POE power supply methods rely on a fixed power supply, which uses an adapter to power the motherboard and POE switch. The POE switch then outputs both data signals and DC power to power the PSE load. However, this power supply method requires the installation of a fixed power supply and power cables, making it difficult for users to remotely power on the PD, making it inconvenient. Summary of the Invention

[0004] In order to enable the motherboard to control the remote power-on of the PD device and facilitate user use, the present application provides a remote POE power supply device and power supply method.

[0005] In a first aspect, the present application provides a remote POE power supply device, which adopts the following technical solution:

[0006] A remote POE power supply device includes a mainboard and a POE switch circuit for connecting to a PD device. The mainboard and the POE switch circuit are connected via a network cable. A POE network card is inserted into the mainboard, and the POE network card supports the WOL function. A step-down circuit is provided on the mainboard, the input end of the step-down circuit is connected to the POE network card, and the output end of the step-down circuit is connected to the power supply input end of the mainboard.

[0007] By adopting the above technical solution, since the network card supports the WOL function, the network card has the function of remote wake-up. After receiving the wake-up signal sent by the user, the POE network card can draw power from the motherboard, and then power the PD device, and reduce the voltage obtained by the POE network card to a voltage that can drive the motherboard through the step-down circuit, thereby achieving the effect of remotely turning on the PD device. There is no need to limit the user's position when turning on, which is convenient for user operation.

[0008] Optionally, the step-down circuit is a Buck step-down circuit including an MP9928 chip.

[0009] By adopting the above technical solution, the MP9928 chip, as a synchronous rectification buck controller, has a wide acceptable input range. It uses PWM current modulation, has precise cycle-by-cycle current limiting, and has good overheat protection and high working efficiency.

[0010] Optionally, the step-down circuit includes an upper bridge circuit and a lower bridge circuit, and the upper bridge circuit and the lower bridge circuit both include a MOS tube, the gate of the MOS tube of the upper bridge circuit is connected to the TG end of the MP9928 chip, the gate of the MOS tube of the lower bridge circuit is connected to the BG end of the MP9928 chip, and the source of the MOS tube of the upper bridge circuit, the drain of the MOS tube of the lower bridge circuit and the SW end of the MP9928 chip are connected.

[0011] By adopting the above technical solution, when the MP9928 chip outputs high and low levels, the MOS tubes in the upper bridge circuit and the MOS tubes in the lower bridge circuit work in turn to reduce the voltage and stably supply power to the POE network card.

[0012] Optionally, both the upper bridge circuit and the lower bridge circuit are double-bridge circuits.

[0013] By adopting the above technical solution, under the premise of ensuring the functions of the upper bridge circuit and the lower bridge circuit, the power consumption of each circuit in the dual-bridge circuit is only half of that of the single-bridge circuit, so that the power consumption of each MOS tube is relatively small and the loss of components is reduced.

[0014] Optionally, a boost circuit is further provided on the mainboard, the input end of the boost circuit is connected to the power supply input end of the mainboard, and the output end of the boost circuit is connected to the POE network card.

[0015] By adopting the above technical solution, under normal power supply conditions, the power supply input end of the motherboard normally supplies power to the motherboard, so that the motherboard can start normally and enter the operating system. At the same time, the power supply voltage can be increased to a voltage that can power the PD device through the boost circuit, thereby avoiding the need for a motherboard to be equipped with two power supplies to realize the POE function.

[0016] Optionally, the boost circuit is a Boost circuit including a MAX15157ATJ chip.

[0017] By adopting the above technical solution, the voltage can be stably increased.

[0018] Optionally, the PSE controller in the POE switch circuit is an IP804 chip.

[0019] By adopting the above technical solution, IP804 supports 4-way PSE function and can control the settings of each network port through I2C. That is, one IP804 can control the connection of 4 RJ45 ports, and 8 IP804 cascades can control 32 RJ45 ports, which is equivalent to connecting 32 PD devices.

[0020] Optionally, the PSE controller in the POE switch circuit is an IP808 chip.

[0021] By adopting the above technical solution, compared with IP804, IP808 can support 8-way PSE functions. When 8 IP808s are cascaded, they can control 64 PD devices, doubling the number of PD devices that can be controlled by the same motherboard and expanding the scope of use.

[0022] Optionally, the port PortN of the PSE controller in the POE switch circuit is connected to the POE network card through a diode, the anode of the diode is connected to the POE network card, and the cathode of the diode is connected to the port PortN of the PSE controller in the POE switch circuit.

[0023] By adopting the above technical solution, the diode can limit the flow of current. When the power is supplied by the PSE device, the diode is cut off. When the POE network card realizes remote power supply, the current can flow through the diode to supply power to the PSE end. The diode is only turned on when the POE network card realizes remote power supply, ensuring the stability of remote power supply.

[0024] In a second aspect, the present application provides a remote POE power supply method, which adopts the following technical solution:

[0025] A remote power supply method, comprising:

[0026] Receive a wake-up signal sent by the user;

[0027] According to the wake-up signal, the POE network card takes 48V voltage from the motherboard;

[0028] The POE network card transmits the 48V voltage to the step-down circuit, and the step-down circuit can reduce the 48V voltage to 12V;

[0029] Deliver 12V voltage to the power input terminal of the motherboard.

[0030] By adopting the above technical solution, users can use wireless communication to transmit the correct circuit to the motherboard from a place far away from the POE device, thereby turning on the motherboard without the need for on-site operation, which is convenient for operation.

[0031] In summary, this application includes at least one of the following beneficial technical effects:

[0032] 1. By waking up the motherboard via the network card, the motherboard can be used as a PD device, realizing the remote start of the POE power supply circuit without the need for on-site operation, which is easy to operate;

[0033] 2. Under normal power supply conditions, the voltage that powers the motherboard can also be used as the voltage for the PD device through the boost circuit, avoiding the need for a motherboard to be equipped with two power supplies to achieve the POE function;

[0034] 3. While keeping other devices unchanged, 8 IP808 cascades can control 64 PD devices, increasing the upper limit of PD quantity. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a module schematic diagram of the remote power supply circuit of an embodiment of the present application.

[0036] Figure 2 It is a structural diagram of the step-down circuit of an embodiment of the present application.

[0037] Figure 3 This is a schematic diagram of the POE switch circuit structure of Example 1 of the present application.

[0038] Explanation of the accompanying symbols: 1. Main board; 2. Step-down circuit; 21. Buck circuit; 211. Upper bridge circuit; 212. Lower bridge circuit; 213. Sampling circuit; 214. Output feedback circuit; 3. Boost circuit; 4. POE network card; 5. POE switch circuit. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solutions and advantages of this application more clear, the following Figure 1-3 It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application.

[0040] The embodiment of the present application discloses a remote POE power supply device.

[0041] Example 1

[0042] Reference Figure 1A remote POE power supply device includes a motherboard 1, the model of the motherboard is J1900. The power input terminal Q of the motherboard 1 can obtain a 12V power supply voltage from the outside through an adapter to power components on the motherboard 1 such as the CPU / memory / hard disk, so that the motherboard 1 can start normally. The motherboard 1 serves as part of the PSE device. A boost circuit 3 is provided on the motherboard 1. The input terminal of the boost circuit 3 is connected to the power input terminal Q of the motherboard 1 to boost the power voltage input by the power input terminal Q. In this application, the boost circuit 3 boosts the 12V power supply voltage to 48V. The output terminal of the boost circuit 3 is connected to the input terminal of the POE network card 4, that is, 48V is output to the POE network card 4 to power the POE network card 4. The output terminal of the POE network card 4 is connected to the POE switch circuit 5 through a network filter. The POE switch circuit 5 is then connected to several PD devices that support POE power supply through an RJ45 interface. In this application, the PD device is a network camera, which works and transmits data under the drive of the 48V power supply voltage.

[0043] In order to facilitate the control of the start and stop of the PD device, the POE network card 4 supports the WOL function, that is, the POE network card 4 has a network wake-up function. When the user sends a data wake-up packet, the motherboard 1 is used as the control part of the PD device to control the startup of the PD device. There is no standby voltage. Figure 1 The POE network card 4 is connected to the output of the boost circuit 3 to obtain a 48V input voltage from the boost circuit 3. The POE network card 4 is connected to the motherboard 1 via the step-down circuit 2. Specifically, the input of the step-down circuit 2 is connected to the output of the POE network card 4, and the output of the step-down circuit 2 is connected to the power input terminal Q of the motherboard 1. The step-down circuit 2 can reduce the 48V voltage obtained by the POE network card 4 to 12V to power the motherboard 1, thereby enabling the motherboard 1 to control the remote power-on of the PD device.

[0044] Reference Figure 2 The step-down circuit 2 includes an MP9928GF-Z chip. The 48V_POE terminal of the POE network card 4 is connected to the IN terminal of the MP9928GF-Z chip. The switching circuit inside the MP9928GF-Z chip can convert the 48V voltage into a pulse voltage with a square wave waveform. The 48V_POE terminal of the POE network card 4 is connected to a first resistor R1 and a second resistor R2 connected in series. The second resistor R2 is grounded. The junction between the first resistor R1 and the second resistor R2 is connected to the EN / SYNC terminal of the MP9928GF-Z chip to provide an enable signal for the chip. At the same time, the junction between the first resistor R1 and the second resistor R2 is grounded through a first capacitor C1. The 48V_POE terminal of the POE network card 4 is grounded through a second capacitor C2, which filters the voltage input signal and the enable signal.

[0045] Reference Figure 2The MP9928GF-Z chip's SS terminal is grounded via a fifth capacitor C5. The COMP terminal is connected to a sixth capacitor C6 and a third resistor R3. The six capacitors C6 and R3 are connected in series, with one end of the sixth capacitor C6 connected to the COMP terminal of the chip, and one end of the third resistor R3 is grounded. A seventh capacitor C7 is connected in parallel with the sixth capacitor C6 and the third resistor R3, forming a feedback and compensation loop that helps stabilize the chip's operation.

[0046] Reference Figure 2 The 48V_POE terminal of the POE network card 4 is connected to the CCM / AAM terminal of the MP9928GF-Z chip via a fourth resistor R4. The connection between the fourth resistor R4 and the CCM / AAM terminal of the chip is grounded via a fifth resistor R5. The FREQ terminal of the chip is connected to a sixth resistor R6 and a seventh resistor R7 connected in series. One end of the seventh resistor R7 is connected to the sixth resistor R6, and the other end of the seventh resistor R7 is grounded, thereby setting the switching frequency for the switching circuit within the chip.

[0047] Reference Figure 2 The TG, SW, and BG terminals of the MP9928GF-Z chip are collectively connected to a buck circuit 21. Buck circuit 21 works with the MP9928GF-Z chip to reduce the voltage to the required 12V, providing the appropriate current required by the load. Buck circuit 21 includes an upper bridge circuit 211 and a lower bridge circuit 212. Upper bridge circuit 211 includes a first MOS transistor DN1 and a second MOS transistor DN2, both of which are N-channel MOS transistors. A tenth resistor R10 is connected in parallel between the source and gate of the first MOS transistor DN1. The drain of the first MOS transistor DN1 and the drain of the second MOS transistor DN2 are both connected to the 48V_POE terminal of the POE network card 4. The gates of the first MOS transistor DN1 and the gates of the second MOS transistor DN2 are both connected to the TG terminal of the chip via a ninth resistor R9. The first and second MOS transistors DN1 and DN2 form a dual-bridge structure. Compared to a single-bridge structure, the dual-bridge structure can provide a smaller input resistance, thereby reducing the power loss of each MOS transistor.

[0048] Reference Figure 2The lower bridge circuit 212 includes a third MOS transistor DN3 and a fourth MOS transistor DN4. Both the third MOS transistor DN3 and the fourth MOS transistor DN4 are N-channel MOS transistors. The gates of the third MOS transistor DN3 and the fourth MOS transistor DN4 are connected to the BG terminal of the chip via an eleventh resistor R11. The drain of the third MOS transistor DN3 is connected to the source of the first MOS transistor DN1. The drain of the fourth MOS transistor DN4 is connected to the source of the second MOS transistor DN2. The sources of the third MOS transistor DN3 and the fourth MOS transistor DN4 are both grounded. The third MOS transistor DN3 and the fourth MOS transistor DN4 also form a dual-bridge structure, thereby reducing the power loss of each MOS transistor.

[0049] Reference Figure 2 The 48V_POE terminal of the POE network card 4 is connected to the BST terminal of the MP9928GF-Z chip via a first diode D1. The first diode D1 is a voltage-stabilizing diode. The anode of the first diode D1 is connected to the 48V output terminal of the POE network card 4, and the cathode of the first diode D1 is connected to the BST terminal of the MP9928GF-Z chip. The cathode of the first diode D1 is connected to an eighth resistor R8 and an eighth capacitor C8 connected in series. One electrode of the eighth capacitor C8 is connected to the eighth resistor R8, and the other electrode of the eighth capacitor C8 is connected to the SW terminal of the chip. The first diode D1 forms a bootstrap circuit, which raises the voltage of the SW terminal to the turn-on voltage of the MOS transistor in the Buck circuit 21.

[0050] Reference Figure 2 The 48V_POE of the POE network card 4 serves as the input of the internal switching power supply of the chip. A ninth capacitor C9, a tenth capacitor C10, and an eleventh capacitor C11 connected in parallel are connected between the upper bridge circuit 211. One pole of the ninth capacitor C9, the tenth capacitor C10, and the eleventh capacitor C11 are all connected to the 48V_POE terminal, and the other poles are all grounded. The three capacitors filter the 48V voltage input by the POE network card 4.

[0051] Reference Figure 2 A sampling circuit 213 is connected to the connection between the source of the second MOS transistor DN2 and the fourth MOS transistor DN4. The sampling circuit 213 includes a twelfth resistor R12 and a twelfth capacitor C12 connected in series. One end of the twelfth resistor R12 is connected to the drain of the fourth MOS transistor DN4, and one end of the twelfth capacitor C12 is grounded.

[0052] Reference Figure 2The junction between the twelfth resistor R12 and the drain of the fourth MOS transistor DN4 is also connected to a first inductor L1. A second inductor L2 is connected in parallel to the first inductor L1. One end of the first inductor L1 is connected to the twelfth resistor R12, and the other end is connected to a thirteenth resistor R13. The thirteenth resistor R13 is connected to fourteenth, fifteenth, sixteenth, and seventeenth resistors R14, R15, R16, and R17, which are connected in parallel. The junction between the thirteenth resistor R13 and the first inductor L1 is connected to the SENSE+ terminal of the MP9928GF-Z chip via an eighteenth resistor R18. The other end of the thirteenth resistor R13 is connected to the SENSE- terminal of the MP9928GF-Z chip via a nineteenth resistor R19. The SENSE+ and SENSE- terminals of the chip draw current from the first and second inductors L1 and L2, and adjust the AV gain within the chip based on the current draw.

[0053] Reference Figure 2 The connection point of the thirteenth resistor R13 and the nineteenth resistor R19 is connected to the voltage feedback terminal FB of the MP9928GF-Z chip. As the load changes, the internal switching frequency is controlled according to the current feedback obtained from the first inductor L1 and the second inductor L2, thereby adjusting the output duty cycle and ultimately stabilizing the output voltage.

[0054] Reference Figure 2 The junction of the thirteenth resistor R13 and the nineteenth resistor R19 is connected to an output feedback circuit 214. The output feedback circuit 214 includes a fifth capacitor C5, a sixth capacitor C6, and a seventh capacitor C7 connected in parallel. The seventh capacitor C7 is a polarized capacitor. The positive electrode of the seventh capacitor C7 is connected to the 12V output terminal along with one electrode of the fifth capacitor C5 and the sixth capacitor C6. The negative electrode of the seventh capacitor C7 is connected to ground along with one electrode of the fifth capacitor C5 and the sixth capacitor C6.

[0055] Reference Figure 2 When the input voltage is high, the upper bridge circuit 211 is turned on, the first MOS transistor DN1 and the second MOS transistor DN2 are turned on, and the current supplies power to the load capacitor. During this period, the current in the first inductor L1 and the second inductor L2 gradually increases, and the inductors convert electrical energy into magnetic energy and store it. After a period of time, the upper bridge circuit 211 is turned off. Since the current in the inductor cannot change suddenly, the lower bridge circuit 212 is turned on, forming a loop, converting the magnetic energy stored in the inductor into electrical energy and releasing it to the output capacitor.

[0056] Reference Figure 2The positive electrode of the seventh capacitor C7 is also connected to a twelfth resistor R12 and a thirteenth resistor R13 connected in series. One end of the twelfth resistor R12 is connected to the positive electrode of the seventh capacitor C7, and one end of the thirteenth resistor R13 is grounded. The twelfth resistor R12 is connected in parallel to a fourteenth resistor R14 and an eighth capacitor C8. The fourteenth resistor R14 and the eighth capacitor C8 are connected in series, thereby filtering the output voltage.

[0057] In order to enable the POE switch circuit 5 to drive as many PD devices as possible, refer to Figure 3 The PSE controller in POE switch circuit 5 is an IP804 chip. The IP804 supports four PSE ports: PortN0, PortN1, PortN2, and PortN3. The circuit connection structures of the four return ports are identical. Taking PortN0 as an example, the chip's PortN0 is connected to a third inductor L3 and a third diode D3 connected in series. The third diode D3 is a voltage-stabilizing diode. The anode of the third diode D3 is connected to the third inductor L3, and the cathode of the third diode D3 is connected to a port P48V_POE of the circuit, namely, the RX tap of the network filter. The 48V port of the circuit is also connected to a ninth capacitor C9. One electrode of the ninth capacitor C9 is connected to the 48V port, and the other electrode of the ninth capacitor C9 is connected to the TX tap of the network filter through port PortN_0. One electrode of the ninth capacitor C9 connected to the circuit port PortN_0 and the anode of the third diode D3 are both grounded through the second diode D2. The second diode D2 is a voltage regulator. The cathode of the second diode D2 is connected to the third inductor L3. The anode of the second diode D2 is grounded.

[0058] The IP804 uses the pins at PortN0, PortN1, PortN2, and PortN3 to identify whether the device on the other end of the PoE network card is a PD. The PD then detects power consumption and status based on the protocol of the other end. The PoE switch circuit 5 is connected to the network filter to provide power to the PD.

[0059] Reference Figure 3 The IP804 chip can communicate with multiple IP804s through its own I2C interface, thereby realizing the cascading of multiple IP804 chips, making it easier to control and collect the status of multiple PD devices without changing the hardware equipment.

[0060] The implementation principle of Example 1 is as follows: since the POE network card 4 has the WOL function, the user remotely sends a wake-up data packet to the POE network card 4, so that the POE network card 4 obtains 48V power from the motherboard, and the voltage is reduced from 48V to 12V through the step-down circuit 2 and transmitted to the power supply input terminal Q of the motherboard 1, which has the effect of remotely turning on the motherboard; at the same time, the POE network card 4 uses the obtained 48V power to power the POE switch circuit 5, and supplies power and transmits data to several PD devices connected to the POE switch circuit 5 through the network cable.

[0061] In addition, when the motherboard 1 is in a normal power supply state, the adapter obtains 12V voltage from the outside world. The 12V voltage is increased to 48V by the boost circuit 3 to power the POE network card 4, and then the POE network card 4 powers the POE switch circuit 5. The POE switch circuit 5 is powered and transmits data with several PD devices through the network cable.

[0062] Example 2

[0063] The difference between this embodiment and embodiment 1 is that, in order to control more PD devices while ensuring that other circuits remain unchanged, the PSE controller in the POE switch circuit 5 is an IP808 chip. The IP808 supports 8-way PSE output, and each output can be connected to a PD device via RJ45.

[0064] Example 3

[0065] The present application also discloses a remote POE power supply method. The method is based on the above-mentioned remote POE power supply device and includes the following steps:

[0066] S100: Acquire a wake-up signal sent by a user.

[0067] S200: According to the wake-up signal, the POE network card with WOL function obtains 48V power from the motherboard.

[0068] Specifically, after the POE network card obtains the 48V voltage, it jumps to S300 and S400 synchronously.

[0069] S300: The step-down circuit reduces the 48V voltage to 12V and transmits it to the power input and output terminals.

[0070] S400: POE network card drives 48V POE switch circuit.

[0071] S500: The POE switch circuit checks and supplies power to the PD device according to the peer protocol.

[0072] The above are all preferred embodiments of the present application and are not intended to limit the scope of protection of this application. Unless otherwise specified, any feature disclosed in this specification (including the abstract and drawings) may be replaced by other equivalent or similar features. In other words, unless otherwise specified, each feature is merely an example of a series of equivalent or similar features.

Claims

1. A remote POE power supply device, comprising a mainboard (1) and a POE switch circuit (5) for connecting to a PD device, wherein the mainboard (1) and the POE switch circuit (5) are connected via a network cable, and is characterized in that: A POE network card (4) supporting the WOL function is inserted into the mainboard (1), and a step-down circuit (2) is provided on the mainboard (1). The POE network card (4) is connected to the power supply input end of the mainboard (1) via the step-down circuit (2). The input end of the step-down circuit (2) receives the 48V voltage of the POE network card (4) and steps it down to 12V and outputs it to the mainboard (1); The mainboard (1) is further provided with a boost circuit (3), the input end of the boost circuit (3) is connected to the power supply input end of the mainboard (1), and the output end of the boost circuit (3) is connected to the POE network card (4), for boosting the 12V power supply of the mainboard (1) to 48V to drive the POE switch circuit (5); The step-down circuit (2) comprises an upper bridge circuit (211) and a lower bridge circuit (212), the upper bridge circuit (211) and the lower bridge circuit (212) both comprising a MOS tube, the gate of the MOS tube of the upper bridge circuit (211) being connected to the TG end of the chip of the step-down circuit (2), the gate of the MOS tube of the lower bridge circuit (212) being connected to the BG end of the chip of the step-down circuit (2), the source of the MOS tube of the upper bridge circuit (211), the drain of the MOS tube of the lower bridge circuit (212) being connected to the SW end of the chip of the step-down circuit (2); the upper bridge circuit (211) and the lower bridge circuit (212) being both dual-bridge circuits; The PSE controller in the POE switch circuit (5) is an IP804 chip or an IP808 chip. The PSE port PortN of the PSE controller is connected to the POE network card (4) through a diode. The positive electrode of the diode is connected to the POE network card (4), and the negative electrode of the diode is connected to the port PortN of the PSE controller. When the power is supplied by the PSE device, the diode is cut off. When the POE network card realizes remote power supply, the power flows through the diode to supply power to the PSE port. The diode is only turned on when the POE network card (4) is remotely powered to ensure the stability of the remote power supply.

2. The remote POE power supply device according to claim 1, wherein: The step-down circuit (2) is a Buck step-down circuit including an MP9928 chip.

3. The remote POE power supply device according to claim 1, wherein: The boost circuit (3) is a Boost circuit including a MAX15157ATJ chip.

4. A remote POE power supply method, characterized in that: Based on the implementation of the remote POE power supply device according to claim 1, the power supply method includes: Receive a wake-up signal sent by the user; According to the wake-up signal, the POE network card (4) takes a 48V voltage from the motherboard (1); The POE network card (4) transmits the 48V voltage to the step-down circuit (2), and the step-down circuit (2) is capable of reducing the 48V voltage to 12V; The 12V voltage is passed to the power input terminal of the mainboard (1).

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