JP2006191377A - Power control system of switching device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To compose a power control system of a switching device that does not require a power supply dedicated to the switching device, such as a hub, a switch, and a modem; and a signal line for supplying power and performing the on-off control of the power supply, and suppresses wasted power consumption. <P>SOLUTION: The switching device 10 has a power receiving power circuit comprising power receiving circuits 12A, 12B, 12C and a power circuit 13. There are power supply circuits 22, 32, 42 in computers 20, 30 connected to the switching device 10, the switching device 40, and the like. Only when communication control circuits 23, 33 perform communication, or a data exchange control circuit 43 performs data exchange control; the power supply circuits 22, 32, 42 are activated for supplying power to the power receiving circuits 12A, 12B, 12C and the power circuit 13 in the switching device. In the switching device 10, no power is supplied from the power supply circuits 22, 32, 42 while no communication is being made, thus interrupting power supply to an internal circuit. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a power control system for a switching device in a local area network in which other nodes are connected to the switching device such as a hub, switch, and modem via a cable of the local area network.

  Conventionally, Patent Documents 1 and 2 are disclosed as inventions relating to power supply control for nodes of a local area network (hereinafter referred to as “LAN”).

  In the system of Patent Document 1, the exchange device supplies power to a server or printer connected to the exchange device (client).

The system of Patent Document 2 uses a link pulse transmitted separately from a signal for data communication. When a link pulse is input while the main power supply of the switching apparatus is off, the main power supply is turned on and the switching apparatus Is activated, and when the link pulse disappears, the switching device is turned off.
JP 2003-158529 A JP 2000-115222 A

  However, in the system of Patent Document 1, since the power supply of the server or printer connected to the exchange device is turned on and off by the exchange device, in order to operate the exchange device, a dedicated power supply is necessary. Further, a power port for supplying power from the exchange device to the server or printer is required. In addition, since the power supply of the exchange device is always on regardless of the on / off state of the power of other nodes connected to the exchange device, data exchange is not performed when data transmission is not performed through this exchange device. The device consumes wasted power.

  In the system of Patent Document 2, since the power supply of the exchange device is turned on and off using a link pulse, a dedicated power supply for operating the exchange device is required. In addition, special link pulse transmission means had to be provided.

  Accordingly, an object of the present invention is to provide an exchange that eliminates the need for a dedicated power source for a switching device such as a hub, switch, or modem, eliminates a signal line for power supply or power on / off control, and suppresses wasteful power consumption. An object is to provide a power control system for an apparatus.

  (1) The present invention provides a switching apparatus power control system in a local area network in which another node is connected to the switching apparatus via a local area network cable. A power receiving power supply circuit that receives power supply via a cable and supplies power to a circuit in the exchange device, and the other node performs data communication with the exchange device via the cable Only with a power supply control means for supplying power to the exchange device via the cable.

(2) The switching apparatus includes a plurality of ports to which the other nodes are connected via a cable of a local area network.
The power receiving power circuit supplies a power supply voltage to a circuit in the exchange apparatus in a state where power is supplied from any one of the plurality of ports via the cable, and power is not supplied from any port. In this state, the power supply to the circuit in the exchange device is stopped.

  (3) The cable is a converging cable of a plurality of twisted pair cables, and the power supply control means superimposes a power supply voltage on a data transmission core wire or a non-data transmission core wire of the converging cable.

  According to the switching apparatus power control system of the present invention, the switching apparatus is powered on only when a node connected to the switching apparatus via a local area network cable transmits data through the switching apparatus. Therefore, wasteful power consumption can be greatly suppressed. In addition, a dedicated power source for the exchange device is not required, and no special signal or cable for power control is required, so that the system is not complicated.

A power supply control system for an exchange apparatus according to the first embodiment will be described with reference to FIGS.
FIG. 1 is a block diagram showing a configuration example of a local area network including a power supply control system of an exchange device. The local area network shown in FIG. 1 includes switching devices 10 and 40 and computers 20 and 30.

  In FIG. 1, a computer 20 includes a jack 21 for connecting a plug of a cable used in a local area network, a power supply circuit 22 that supplies power via the cable, and a communication control circuit that performs communication control via the same cable. 23.

  The cable is, for example, a twisted pair converging cable used in standards such as 100BASE-TX and 1000BASE-T with RJ-45 plugs attached to both ends. The jack 21 is a jack into which the RJ-45 plug is inserted.

  The power supply circuit 22 is a PoE (Power over Ethernet (registered trademark)) standardized by IEEE 802.3af, that is, a circuit (PSE: Power Sourcing Equipment) for supplying / receiving power with Ethernet (registered trademark). .

  Another computer 30 in FIG. 1 has the same configuration as the computer 20 and includes a jack 31, a power feeding circuit 32, and a communication control circuit 33.

  The exchange device 40 includes jacks 41A and 41B for inserting cable plugs, a power feeding circuit 42, and a data exchange control circuit 43. The jacks 41A and 41B of the exchange device 40 are inserted with cable plugs in the same manner as the jacks 21 and 31 of the computers 20 and 30. Similarly to the power supply circuits 22 and 32 in the computers 20 and 30, the power supply circuit 42 supplies power to the connected power reception circuit via a cable. The data exchange control circuit 43 exchanges data with devices connected to the jacks 41A and 41B via cables.

  The exchange device 10 includes jacks 11A, 11B, 11C, and 11D, power receiving circuits 12A, 12B, and 12C, a power supply circuit 13, and a data exchange for connecting a plug of the local area network cable (hereinafter simply referred to as “cable”). A control circuit 14 is included.

  The power receiving circuits 12A, 12B, and 12C are circuits (PD: Powered Devices) that receive power from the power supply circuit (PSE) by the PoE.

  The power receiving circuit 12 </ b> A receives power supply from the power feeding circuit 22 of the computer 20 via the cable 101. In addition, the power supply circuit 12 </ b> B receives power supply from the power supply circuit 32 of the computer 30 via the cable 102. Similarly, the power feeding circuit 12 </ b> C receives power supply from the power feeding circuit 42 of the exchange device 40 via the cable 103.

  The power supply circuit 13 receives power at the power receiving circuits 12A, 12B, and 12C, converts the power into a predetermined power supply voltage, and supplies it to a circuit inside the exchange apparatus 10.

  The power receiving circuits 12A, 12B, 12C and the power supply circuit 13 constitute a “power receiving power circuit” according to the present invention.

  The data exchange control circuit 14 performs data input / output control between the ports PA, PB, PC, PD corresponding to the jacks 11A, 11B, 11C, 11D, respectively. In this example, data exchange control is performed with the communication control circuits 23 and 33 of the computers 20 and 30 or the data exchange control circuit 43 of the exchange device 40 via the cables 101, 102 and 103. For example, when a data packet is transmitted from the computer 20 to the computer 30, the data exchange control circuit 14 reads the destination IP address of the packet received from the computer 20, and outputs the packet to the corresponding port PB.

  The computers 20 and 30 and the exchange device 40 shown in FIG. 1 operate the power supply circuits 22, 32, and 42 only when data transmission is performed via the exchange device 10, and stop in other states. The outputs of the power receiving circuits 12A, 12B, and 12C are connected in parallel and supplied to the power supply circuit 13. Therefore, if at least one of the power receiving circuits 12A, 12B, and 12C is receiving power, the power supply circuit 13 generates a predetermined power supply voltage. When any of the power receiving circuits 12A, 12B, and 12C is not supplied with power, the input power to the power supply circuit 13 is lost. Therefore, the supply of power supply voltage to each part of the circuit inside the exchange device 10 is interrupted, and the exchange device 10 Stops its operation.

  FIG. 2 is a specific circuit diagram of the power receiving circuits 12A, 12B, and 12C shown in FIG. Since each of the power receiving circuits 12A, 12B, and 12C has the same configuration, the power receiving circuit 12A will be described as a representative here.

  The power receiving circuit 12A includes a jack 11A into which a cable plug is inserted, a pulse transformer PT1, and diode bridges DB11 and DB12. Since the jack 11A is an RJ-45 connector jack as described above, the 8-pin signal names are as follows.

1: + TD → reception +
2: -TD-> reception-
3: + RD → Send +
4: For power transmission 5: For power transmission 6: -RD-> Transmission-
7: For power transmission 8: For power transmission The pulse transformer PT1 is a two-system pulse transformer having a center tap for both input and output. The first and second pins of the jack 11A are connected to the PHY via one pulse transformer of the pulse transformer PT1. Signals are transmitted to the chip. Further, the signals of the 3rd and 6th pins of the jack 11A are transmitted to the PHY chip through another pulse transformer of the pulse transformer PT1. This PHY chip is a so-called physical layer device, and performs signal processing on communication signals of Ethernet (registered trademark).

  Further, the 4th and 5th pins and the 7th and 8th pins are connected to the diode bridge DB12 so that the rectified output is supplied to the power supply circuit 13 described later. The center tap on the input side of the two pulse transformers of the pulse transformer PT1 is connected to the diode bridge DB11. Thus, the diode bridge DB 11 rectifies the signal for power transmission superimposed between the 1st and 2nd pins and the 3rd and 6th pins of the jack 11A and supplies the signal to the power supply circuit 13.

  FIG. 3 is a circuit diagram of the power supply circuit 13 shown in FIG. A combined signal of the output signals of the power receiving circuits 12A, 12B, and 12C shown in FIG. The power supply circuit 13 includes a so-called PD controller PDC and a DC-DC converter CNV. The PD controller PDC detects whether power is received and controls the DC-DC converter CNV. That is, if a DC voltage is output from any of the power receiving circuits 12A, 12B, and 12C shown in FIG. 2, the DC-DC converter CNV is activated.

  The DC-DC converter CNV steps up and down the DC voltage input to the + VIN and −VIN to a predetermined voltage and outputs it to + VOUT and −VOUT. This output voltage becomes a power supply voltage for each circuit in the exchange device 10.

  FIG. 4 is a flowchart showing the processing contents of the communication control circuit 23 of the computer 20 shown in FIG. First, the presence / absence of a communication process is determined. If there is a process to be communicated, the power supply circuit (PSE) 22 is activated (S1 → S2). Subsequently, predetermined data transmission is performed (S3). When there is no longer processing to communicate, the operation of the power feeding circuit (PSE) 22 is stopped (S4). The processing contents of the communication control circuit 33 of the computer 30 are the same as those of the communication control circuit 23.

  Similarly, for the exchange device 40, the data exchange control circuit 43 performs communication with a node (the exchange device 10 in the example shown in FIG. 1) connected to the jack 41A via a cable. Only the power supply circuit (PSE) 42 is activated to supply power to the switching apparatus 10. When the communication is not performed, the operation of the power feeding circuit (PSE) 42 is stopped.

  When communication processing is performed in this way, power is supplied to the switching device unit 10 shown in FIG. 1 via the cable 101. When communication is not performed, the power supply is stopped. The exchange device 10 can be activated.

  As described above, the exchange device 10 performs data exchange processing by receiving power supply only when communicating with another node (computer or other exchange device) connected via a cable. The power is cut off when no power is supplied from any of the nodes, and wasteful power consumption can be suppressed.

Next, a power supply control system for an exchange apparatus according to the second embodiment will be described with reference to FIG.
FIG. 5 is a block diagram showing a configuration of a local area network including a power supply control system for an exchange apparatus according to the second embodiment. The exchange device 50 is connected to a computer 60 via a cable 201 and another exchange device 70 via a cable 202. The configuration of the computer 60 is the same as that of the computers 20 and 30 shown in FIG. 1, and includes a jack 61 into which a cable plug is inserted, a power feeding circuit 62, and a communication control circuit 63. The exchange device 50 includes jacks 51A, 51B, 51C for inserting cable plugs, power receiving circuits 52A, 52B, a power supply circuit 53, a data exchange control circuit 54, and a power feeding circuit 55. The configuration of the power receiving circuits 52A and 52B is the same as that of the power receiving circuits 12A, 12B, and 12C shown in the first embodiment. The power supply circuit 55 receives the power supply voltage output from the power supply circuit 53, and supplies power to the node connected to the jack 51C with PoE.

  The exchange device 70 includes jacks 71A and 71B into which cable plugs are inserted, power receiving circuits 72A and 72B, a power supply circuit 73, and a data exchange device 74. The power receiving circuits 72A and 72B have the same configuration as the power receiving circuits 12A, 12B, and 12C shown in the first embodiment. The power supply circuit 73 is the same as the power supply circuit 13 of the exchange device 10 shown in FIG. The data exchange control circuit 74 is the same as the data exchange control circuit 14 shown in FIG.

  The second embodiment is characterized in that the exchange device 50 includes a power feeding circuit 55 together with the power receiving circuits 52A and 52B.

  When the computer 60 communicates with a node on the network (computer 80 in this example), the power feeding circuit 62 is activated in the same manner as the operation described in the first embodiment. Thus, the power supply voltage is supplied to the circuit inside the exchange device 50 by the action of the power receiving circuit 52A and the power supply circuit 53 of the exchange device 50. At the same time, the power receiving circuit 55 supplies power to the power receiving circuit 72A of the exchange device 70 via the cable 202. As a result, the power supply voltage is supplied to the circuit inside the exchange device 70 by the action of the power receiving circuit 72A and the power supply circuit 73.

  Note that when the computer 80 activates the power feeding circuit 82, the power feeding circuit 82 feeds power to the power receiving circuit 72 </ b> B of the exchange device 70. The power supply voltage is also supplied to the circuit inside the exchange device 70 by the action of the power receiving circuit 72B and the power supply circuit 73.

  When the communication between the computer 60 and the computer 80 is completed, the operation of the power feeding circuit 62 is stopped, so that the power output of the power supply circuit 53 is stopped. Along with this, power feeding in the path from the power feeding circuit 55 → the cable 202 → the power receiving circuit 72 </ b> A → the power supply circuit 73 is stopped. Further, when the communication by the communication control circuit 83 of the computer 80 is completed, the operation of the power feeding circuit 82 is stopped, so that power feeding is performed on the path from the power feeding circuit 82 → the cable 203 → the power receiving circuit 73 B → the power supply circuit 73. Also stop. Thereby, the power receiving to the power receiving circuit 72B of the exchange device 70 is stopped, and the wasteful power consumption of the exchange device 70 can be reduced.

It is a block diagram which shows the structure of the whole local area network containing the power supply control system of the switching device which concerns on 1st Embodiment. It is a circuit diagram of the electric power receiving circuit in the switching device used in the system. It is a circuit diagram of the power supply circuit in the same exchange apparatus. It is a flowchart which shows operation | movement of the communication control circuit in the computer shown in FIG. It is a block diagram which shows the structure of the whole local area network containing the power supply control system of the switching device which concerns on 2nd Embodiment.

Explanation of symbols

10, 40, 70-switching device 11, 21, 31, 41, 51, 61, 71-jack 12, 52, 72-power receiving circuit (PD)
13-Power supply circuit 14, 43-Data interchangeability control circuit 20, 30, 60, 80-Computer 22, 32, 42, 62-Power supply circuit (PSE)
23, 33, 63-communication control circuit 101-103, 201-203-cable

Claims (3)

In a power control system for a switching device in a local area network in which other nodes are connected to the switching device via a local area network cable,
The switching apparatus includes a power receiving power supply circuit that receives power from the other node via the cable and supplies power to a circuit in the switching apparatus.
The other node includes power supply control means for supplying power to the switching apparatus via the cable only in a state where data communication is performed with the switching apparatus via the cable. Power control system for switching equipment. The switching apparatus includes a plurality of ports to which the other nodes are connected via a local area network cable,
The power receiving power circuit supplies a power supply voltage to a circuit in the exchange apparatus in a state where power is supplied from any one of the plurality of ports via the cable, and power is not supplied from any port. The power supply control system for an exchange apparatus according to claim 1, wherein power supply to a circuit in the exchange apparatus is stopped in a state.   The cable is a converging cable of a plurality of twisted pair cables, and the power supply control means superimposes a power supply voltage on a data transmission core wire or a non-data transmission core wire of the converging cable. A power control system for the described exchange device.

Images