JPH10171562A - Power supply device and power supply system using the power supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply device capable of preventing the generation of useless power consumption and a power supply system using the power supply device. SOLUTION: The power supply system is provided with plural power supply devices 10, 20, 30 each of which includes a power supply part P (P1 , P2 , P3 ) for outputting a power supply current connection terminals T1 , T2 connected to a power supply cable C1 for supplying the power supply current from the power supply part P and a power supply control means S for comparing the voltage value detected through the terminals T1 , T2 with a reference voltage value set up more than the output voltage value of the power supply part P and controlling the power supply part P so as to turn off the output of the power supply current when the detected voltage is higher than the reference voltage value and turn on the output of the power supply current when the detected voltage is lower than the reference voltage value based on the compared result and these power supply devices 10, 20, 30 are mutually connected through the power supply cables C1 .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a power supply device used as an interface for establishing a connection between electronic devices in a computer system and a power supply system using the power supply device, and more particularly, to an IEEE 1394 high performance serial system. Bus (hereinafter simply IEEE)
It is called E1394. )).

[0002]

2. Description of the Related Art In general, in a computer system of a personal computer (hereinafter referred to as a personal computer), it is general that a personal computer and other peripheral devices are connected by a cable via an interface for each peripheral device. is there. In the computer system, various devices such as a CRT display, a keyboard, a mouse, a printer, a modem, an image scanner, and an external storage device are used as the peripheral devices, and more recently, a video camera, an electronic still camera, and the like. Have also been used in connection with personal computers, and their types have been increasing and diversifying.

[0003] In response to this tendency, in recent years, for example, IEEE
As seen in E1394 and the like, a method has been proposed in which various peripheral devices can be connected by a unified interface, and power supply current for the interface can be supplied between the devices.

In this IEEE 1394, as shown in FIG. 4, three pairs of cables C ₁ , C ₂ , C
And each of the electronic devices are connected by a cable C provided with a C _3. Of these, the first cable C ₁ consisting of the line L ₁ and the line L ₂ Metropolitan has a power cable for supplying power current for the interface. Also,
A second cable C ₂ composed of a twisted pair of the line L ₃ and the line L ₄ is a cable for transmitting a protocol signal,
Third cable C ₃ consisting of twisted pairs of lines L ₅ and the line L ₆ is a cable for data transfer.

The cable C has both ends at each electronic device 10.
It is connected to a power supply device to be described later in detail through connection terminals T _{1 to} T ₆ of 0.

[0006]

In IEEE 1394, as hardware, a physical layer that defines a serial signal encoding method and electrical specifications of a signal, and a link layer that defines a low-level protocol for operations such as reading and writing are provided. And In the IEEE 1394 interface, a plurality of electronic devices 100 can be connected in various forms via the cable C. In such a case, all the controllers constituting the physical layer in each electronic device 100 may be connected. It is required that a load circuit such as an LSI is in a so-called live state.

Therefore, in the IEEE 1394 interface, even if the power of the main body of an electronic device 100 is turned off, the load circuit of the electronic device 100 is connected to the other electronic device 100 connected by the cable C.
It is configured to be driven by a power supply unit from the PC.
That is, in the power supply system in the IEEE1394, by containing the above-described power cable C ₁ on the cable C, for example, a personal computer can be supplied with power directly through the cable C with respect to the load circuit of the peripheral device.

FIG. 5 shows a conventional power supply device and power supply system for an IEEE 1394 interface.
This will be described with reference to FIG. In FIG. 5, each of the power supplies 101, 102, and 1 in each of the electronic devices when the three electronic devices are connected to each other via the cable C.
An example is shown in which 03 is extracted and represented.

Each of the power supply units 101, 102, and 103 is connected to a power supply unit P for supplying a DC power supply current, a load circuit R including a controller LSI constituting the physical layer, and a positive terminal of the power supply unit P. Terminals T (T ₁ , T ₂ ) for connecting the protected diode D to other electronic devices.
And is provided.

[0010] In each of these power supply 101 to 103, and the positive electrode side protective diode D of each power unit _{P (P 1, P 2,} P 3) (D 1, D 2, D 3), the load circuit R (R ₁ , R
₂ , R ₃ ) and the connection terminal T _1, and the negative terminal of each power supply unit P, the other end of each load circuit R, and the connection terminal T ₂ are grounded. It is configured to:

Here, in each power supply section P, the power supply section P
₁ the voltage of the 12 volt power supply unit P ₂ is 9 volts, the power supply portion P ₃ is adapted to output a power supply each at a voltage of 11 volts.

Each of the power supply units 101 to 103 is connected by a cable C shown in FIG. 4 provided with a power supply cable C ₁ and two signal cables C ₂ and C ₃ , thereby forming one power supply system. Make up.

In the above power supply system, power can be supplied to all the load circuits R _{1 to} R ₃ by operating any one of the power supply units P. On the other hand, the power supply system, when the cells are driven each power unit P ₁ to P ₃ is a so-called switching function of the protection diode D ₂ and D _3, all the power of the power supply unit P ₁ of the highest 12 volts load circuits R ₁ through R ₃ is to be driven.

Furthermore, in the power system, even when the operation of the power supply unit P ₁ of the power supply device 101 is stopped, each load circuit R ₁ to R ₃ by the operation of the power supply unit P ₃ of the power supply device 103 It will be driven. This allows
In this power supply system, even when the power supply of the electronic device including the power supply 101 is turned off, the power supply 10
2 does not interfere with data transfer between the electronic device including the power supply device 103 and the electronic device including the power supply device 103.

However, in IEEE 1394, since the power supply for the load circuit constituting the physical layer is always operating in each electronic device, there is a problem that wasteful power is used. Though specifically, in the power supply system, when the cells are driven each power unit P ₁ to P _3, to drive the respective load circuits R ₁ to R ₃ as described above are performed by only the power supply unit P ₁ not have always had since been other power source portion P ₂ and P ₃ is also actuated, resulting in wasteful power consumption as a whole system, that the problem.

The present invention has been proposed to solve the above-mentioned problems, and provides a power supply device capable of preventing wasteful power consumption and a power supply system using the power supply device. With the goal.

[0017]

To solve the above-mentioned problems, a power supply unit according to the present invention has a power supply unit for outputting a power supply current and a connection terminal to which a power supply cable for supplying a power supply current from the power supply unit is connected. And, based on the comparison result of the voltage value comparison means, which compares the voltage value detected via the connection terminal with the reference voltage value set to be equal to or higher than the output voltage value of the power supply unit, When the detected voltage is higher than the reference voltage value, the power supply current output is turned off,
Power supply control means for controlling the power supply to turn on the output of the power supply current when the detected voltage is lower than the reference voltage value;

According to the power supply device, the operation of the power supply unit is automatically stopped when a voltage value higher than the reference voltage value is detected, so that wasteful power consumption can be prevented.

Further, in order to solve the above problems, the power supply system according to the present invention comprises: a power supply section for outputting a power supply current; a connection terminal to which a power supply cable for supplying a power supply current from the power supply section is connected; Voltage value comparing means for comparing the level of the voltage value detected via the power supply unit with the reference voltage value set to be equal to or higher than the output voltage value of the power supply unit, and the detected voltage is determined based on the comparison result of the voltage value comparing means. The power supply unit is controlled so that the output of the power supply current is turned off when it is higher than the reference voltage value, and the output of the power supply current is turned on when the detection voltage is lower than the reference voltage value. A plurality of power supply devices each including a power supply control unit are provided, and each of these power supply devices is mutually connected by a power cable.

According to the power supply system, when a voltage value higher than the reference voltage value is detected, the operation of one of the power supply units is automatically stopped, so that the number of activated power supply units is reduced. Useless power consumption of the entire system is prevented.

[0021]

Embodiments of the present invention will be described in detail with reference to the drawings. In this embodiment, a case is shown in which the present invention is applied to a power supply device for an IEEE 1394 interface. However, the present invention is not limited to such a case and does not depart from the scope of the claims. Of course, it can be applied to various interfaces.

As shown in FIG. 1, the power supply unit includes a power supply unit P
, A protection diode D, a load circuit R, a voltage sensor S, and a connection terminal T for connecting to other electronic devices.
(T ₁ , T ₂ ).

In this power supply device, the positive side of the power supply unit P is connected to the anode side of the protection diode D, and the cathode side of the protection diode D is connected to one electrode side of the load circuit R and one side of the voltage sensor S, respectively. , Connection terminal T
With ₁ are sequentially connected, the negative side of the power supply unit P, the other electrode side of the load circuit R, the other electrode side of the voltage sensor S, and the connection terminal T ₂ are configured to be grounded.

The power supply section P outputs a DC power supply current. In this embodiment, the output voltage is 9 volts. ON / OFF of the output of the power supply unit P is controlled by a control signal from a voltage sensor S described in detail later.

The protection diode D disconnects the connection between the power supply unit P and the load circuit R when the output voltage of another power supply device described later is higher than the output voltage of the power supply unit P, and at the same time, the protection diode D Has a function as a switch for protecting the power supply unit P by preventing the power supply current from flowing to the power supply unit P side.

The connection terminals T ₁ and T ₂ are for connecting to other electronic devices, and can be connected to the power cable C ₁ provided with the lines L ₁ and L ₂ shown in FIG. It has become. Voltage sensor S, together with one electrode connected to the positive electrode side of the power unit P through the protective diode D, is connected ₁ both connection terminals T, which is the electrode and the input side of the power supply current .

This voltage sensor S has a voltage value comparing function for comparing the level of a voltage value detected via the connection terminal T ₁ with two reference voltage values which will be described in detail later.

The voltage sensor S outputs a control signal to the power supply unit P. In an initial state, the voltage sensor S outputs a control signal for operating the power supply unit P (hereinafter, this control signal is a control signal for turning on the control signal). Is output, and when the detected voltage value is higher than the first reference voltage value, a control signal for stopping the operation of the power supply unit P (hereinafter, this control signal is turned off)
Control signal. ) Is output. Further, the voltage sensor S outputs an ON control signal to the power supply unit P when the detected voltage value becomes lower than the second reference voltage value.

That is, the reference voltage value includes a first reference voltage value at which the output control signal changes from ON to OFF and a second reference voltage value at which the control signal changes from OFF to ON. It is set to a value equal to or higher than the output voltage value of the section P. Each of these reference voltage values is desirably equal to the output voltage value of the power supply unit P from the viewpoint of minimizing waste of power. However, the output voltage of the power supply unit in the power supply unit P and other electronic devices (not shown) is preferable. The first reference voltage value is set to 11 volts, and the second reference voltage value is set to 10 volts in consideration of the fluctuation of the voltage, the detection error of the voltage sensor S, and the like.

Hereinafter, the relationship between each reference voltage value and the control signal in the voltage sensor S will be described with reference to FIG. The voltage sensor S outputs an ON control signal in an initial state. Then, the voltage sensor S outputs an OFF control signal when the detected voltage value becomes 11 volts or more. The voltage sensor S needs to have a detected voltage value of 10 volts or less in order to shift from this state of outputting an OFF control signal to the initial state of outputting an ON control signal.

When the voltage sensor S is set as described above, the detected voltage is 10 volts or 1 volt.
Instability of the output state of the control signal at around 1 volt is prevented, and the switching operation of the power supply to the load circuit R is performed smoothly.

In the case where the power supply unit is desired to have upward compatibility with the conventional power supply unit described with reference to FIG. May be set so that the power supply unit P always operates by setting the reference voltage value to infinity (hereinafter, this setting is referred to as a normal mode).

The power supply having the above configuration is, for example,
When another electronic device is not connected, or when another electronic device is connected via each connection terminal T but has an output voltage of 10 volts or less, the voltage sensor S turns on the power supply unit P. Is output, the load circuit R is driven by the power supply unit P.

On the other hand, another electronic device is connected via each connection terminal T, and the power source of the other electronic device is
In the case of an output voltage equal to or higher than volts, the operation of the power supply unit P is stopped by outputting an OFF control signal from the voltage sensor S to the power supply unit P. Thus, in the power supply device, the load circuit R is driven by the power supply unit (not shown) of the other electronic device, so that useless power consumption is prevented.

Next, a power supply system using a plurality of the power supply devices and connecting the power supply devices with cables will be described with reference to FIG. Incidentally, in FIG. 3, three power supplies 10, 20 and 30 showed an example of a power supply system is configured by connecting the cable C _1, in the present invention, the number and connections of the connected power supply The embodiment is not particularly limited.

[0036] Each power supply 10, 20, with each DC power supply current supplied power unit _{P (P 1, P 2,} P 3),
A load circuit R (R ₁ , R ₂ , R ₃ ) including a controller LSI constituting a physical layer, a protection diode D connected to the positive side of each power supply unit P, and the voltage sensor S (S ₁ ,
S ₂ , S ₃ ) and connection terminals T (T ₁ , T ₂ ) for connecting to other electronic devices.

[0037] In each of these power supplies 10, 20, 30, a positive electrode side protective diode D of the power supply unit P, a one end of the load circuit R, and one end of the voltage sensor S, sequentially the connection terminals T ₁ is connected, the negative side of the power supply unit P, a second end of each load circuit R, and the other end side of each voltage sensor S, a connection terminal T ₂ are configured to grounded.

[0038] Here, each power unit P is adapted to P ₁ is the voltage of 12 volts, P ₂ is 9 volts voltage, is P ₃ outputs the respective supply current at a voltage of 10 volts.

For each voltage sensor S, the output control signal for the voltage sensor S ₁ is changed from ON to O
The first reference voltage value for the FF state is set to 14 volts, and the second reference voltage value for the control signal to change from the OFF state to the ON state is set to 13 volts. Voltage sensor S
_{For 2} , the first reference voltage value is 11 volts,
The second reference voltage value is set to 10 volts. The voltage sensor S _3, the first reference voltage value to 12 volts, and the second reference voltage value respectively set to 11 volts.

Each of the power supply units 10 to 30 is connected by a cable C shown in FIG. 4 provided with a power supply cable C ₁ and two signal cables C ₂ and C ₃ , thereby forming one power supply system. Make up.

In this power supply system, each of the power supply units P _{1 to} P ₃
Is activated, the so-called switching function of the protection diodes D ₂ and D ₃ causes the highest 12 volt power supply P
All load circuits R ₁ through R ₃ will be driven by the _first current.

[0042] At this time, in the power supply system, since each voltage sensor S _1, S _2, S ₃ detects the voltage value of 12 volts, the voltage sensor S ₁ to the power supply unit P ₁ O
N control signal, the voltage sensor S ₂ outputs an OFF control signal to the power supply unit P ₂ , and the voltage sensor S ₃ outputs an OFF control signal to the power supply unit P ₃ .
Operation of the power unit P ₂ and P ₃ is stopped.

Therefore, in this power supply system, all the load circuits R ₁ , R ₂ , R ₃ are driven by _one power supply unit P ₁ , and the operation of the other power supply units P ₂ and P ₃ is automatically performed. Since the operation is stopped, useless power consumption is prevented.

[0044] Incidentally, in the power supply system, for example, is substantially the output voltage of the same 12 volt power supply unit P ₃ and the power supply unit P _1, when the power supply unit P ₂ is a 9 volt output voltage lower than the The normal mode is set for each of the voltage sensors S ₁ and S ₂ of the power supply device 10 and the power supply device 20, so that the power supply device 20
The load circuit R ₂ can be driven in parallel. The power system, even in this case, the voltage sensor S ₂ and outputs a control signal of the OFF to the power unit P ₂ in the power supply device 20,
Since the operation of the power supply portion P ₂ is stopped, wasteful power consumption of the whole power supply system can be prevented.

The setting of the normal mode is as shown in FIG.
If to perform a bus command using the second cable C ₂ shown in, it is possible to easily set the power source device of a plurality of electronic devices from a single electronic device.

[0046]

As described in detail above, according to the power supply device of the present invention, the operation of the power supply unit is automatically stopped when a voltage value higher than the reference voltage value is detected. Therefore, useless power consumption is prevented.

Further, according to the power supply system of the present invention, when a voltage value higher than the reference voltage value is detected, the operation of any one of the power supply units is automatically stopped so that the power supply unit operates. Since the number is reduced, useless power consumption of the entire system is prevented.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a configuration of a power supply device to which the present invention is applied.

FIG. 2 is a diagram illustrating a relationship between a detection voltage and a control signal in a voltage sensor.

FIG. 3 is a circuit diagram showing an example of a power supply system in which a number of power supply devices are connected by cables.

FIG. 4 is a diagram showing a configuration of an IEEE 1394 cable.

FIG. 5 is a circuit diagram showing a configuration of each power supply device in a conventional computer system.

[Explanation of symbols]

10, 20, 30 power _{supply, P (P 1, P 2} , P 3)
Power unit, D protective _{diode, R (R 1, R 2} , R 3)
Load circuit, S (S ₁ , S ₂ , S ₃ ) voltage sensor, T
(T _1, T ₂₎ connection terminal

Claims (4)

[Claims] A power supply unit for outputting a power supply current; a connection terminal to which a power supply cable for supplying a power supply current from the power supply unit is connected; a voltage value detected via the connection terminal; Voltage value comparing means for comparing the level with a reference voltage value set to be equal to or higher than the output voltage value, and based on a comparison result of the voltage value comparing means, the detected voltage is determined to be higher than the reference voltage value. Power supply unit control means for controlling the power supply unit to turn off the output of the power supply current and to turn on the output of the power supply current when the detected voltage is lower than the reference voltage value. A power supply device characterized by the above-mentioned. 2. The power supply device according to claim 1, wherein the power supply unit control means includes a control mode for controlling output of a power supply current in the power supply unit to be always ON. 3. A power supply section for outputting a power supply current, a connection terminal to which a power supply cable for supplying a power supply current from the power supply section is connected, and a voltage value detected via the connection terminal and a voltage value of the power supply section. When the detected voltage is determined to be higher than the reference voltage value based on a comparison result of the voltage value comparison unit that compares the level with a reference voltage value set to be equal to or higher than the output voltage value. Power supply unit control means for controlling the power supply unit to turn off the output of the power supply current and to turn on the output of the power supply current when the detected voltage is lower than the reference voltage value. A power supply system comprising a plurality of devices, each of which is connected to each other by the power cable. 4. The power supply system according to claim 3, wherein the power supply unit control means is provided with a control mode for controlling output of a power supply current in the power supply unit to be always ON.