JP2001037208A - Power source control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a power source control device wherein connection work is not generated when a power source is loaded, and control is easy, in satellite communication terminal equipment or the like. SOLUTION: In this power source control device, a DC/DC converter 1 is made a power source, and a remote terminal 5, a transistor Tr1 for switching and a resistor R for current supply are installed on an external power source supplying side of the converter. In the initial state that an external power source 2 is loaded, the transistor Tr1 for switching is turned on, and the DC/DC converter 1 is turned into an on-state. By connecting the remote terminal 5 with a ground level in the outside, the transistor Tr1 for switching is turned off, and the DC/DC converter 1 is turned into the off-state. The power source is thus controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal device using a DC / DC converter capable of controlling output as a power source, such as a satellite communication terminal.

[0002]

2. Description of the Related Art In recent years, many electronic devices, whether portable or stationary, are widely used as power supply voltage supply devices.
A C / DC converter is used. In some cases, the remote control of turning on / off the power of the electronic device is performed from outside by remote control.

FIG. 3 shows a configuration diagram of a conventional power supply control device. This power supply control device includes a DC / DC converter 1 capable of controlling output for supplying DC power,
The DC converter 1 has a control terminal. When the level of the input voltage to this terminal is higher than a certain value, that is, when it is at a high level, no output is performed, and when it is at a ground level, that is, at a low level, output is performed. In the figure, reference numeral 2 denotes an external power supply to be supplied, and reference numeral 3 denotes a system power supply made by the DC / DC converter 1. Reference numeral 4 denotes a power supply control signal that turns on the power supply when active and turns off the power supply when inactive. R1 denotes a power supply resistance for keeping the potential of the power supply control signal 4 at a constant level.

The operation of the conventional power supply control device will be described below. The power supply control device as shown in FIG. Here, when the power control signal 4 is maintained at a high level by the power supply resistor R1, the DC / DC converter 1 is in an inactive state, and no potential is supplied to the system power supply 3. Next, when the power control signal 4 is directly connected to the ground level, the power control signal 4 becomes active, and a potential is supplied from the DC / DC converter 1 to the system power supply 3. That is, if the power control signal 4 is extracted to the outside, it is possible to remotely control the on / off of the power of the electronic device by remote control from the outside. To turn on the power supply, connect it to the ground level externally.

In general, power supplies are controlled in combination so that they can be turned on / off not only from external signals but also from a target system.

[0006]

In the power supply control device, since a signal for remote control is turned on when it is externally set to a ground level, a connection operation always occurs when power is turned on. Was troublesome.

[0007]

SUMMARY OF THE INVENTION In order to solve this problem, the present invention relates to a terminal device using a DC / DC converter capable of controlling output as a power supply. A power supply control device that turns on the power supply in an initial state without performing connection work, and turns off the switching transistor by connecting a remote terminal to a ground level externally.

According to the present invention, power is supplied to a target terminal device in an initial state in which external power is turned on, the terminal is turned on without performing external connection work, and the remote terminal is externally grounded. By connecting to the level, the switching transistor is turned off, and the power supply control becomes easy.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention according to a first aspect of the present invention is directed to a terminal device using a DC / DC converter capable of controlling output as a power supply, a current supply resistor for receiving a current from an external power supply, and a switching device. Transistors and
By providing a remote terminal that can be extracted to the outside of the device as an input signal of the switching transistor, the switching transistor is turned on by a current supply resistor in an initial state, and the remote terminal is externally connected to the ground level. A power supply control device that turns off the switching transistor, supplies power to the target terminal device in an initial state when external power is turned on, and turns on the terminal without performing external connection work, The terminal has a function of turning off the terminal by an external connection of the remote terminal and facilitating power control.

According to a second aspect of the present invention, there is provided the power supply control device according to the first aspect, further comprising a switching device that allows a user to arbitrarily select a logical level of remote control. In addition, the user can set whether to turn on or off the power of the terminal with the remote terminal of the terminal device released, and has an effect of facilitating power control.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First Embodiment) FIG. 1 is a configuration diagram of a power supply control device according to a first embodiment of the present invention. Note that, in this figure, the same components as those of the conventional technology are denoted by the same reference numerals as those of the conventional technology.

The power supply control device according to the first embodiment has a structure shown in FIG.
DC / DC converter 1 whose output can be controlled as shown in FIG.
The power supply is supplied from an external power supply 2 to obtain a system power supply 3. When the power supply control signal 4 is kept at a high level by a power supply resistance R1, a DC / DC Converter 1 is in an inactive state and the potential is supplied to system power supply 3. When power supply control signal 4 is directly connected to the ground level, power supply control signal 4 becomes active, and DC / DC converter 1 transmits power to system power supply 3. An electric potential is supplied. These configurations and operations are the same as those of the above-mentioned conventional technology.

The features of the power supply control device according to the first embodiment are as follows.
A remote terminal 5 that can be used as a control signal that can be remotely controlled from the outside is provided. Further, a current supply resistor R is provided, and is controlled by the remote terminal 5 and is supplied from an external power supply 2 by a power supply resistor R1. Is provided.

Next, the operation of the power supply control device of the first embodiment having the above configuration will be described.

In the initial state, a potential is supplied to the external power supply 2,
It is also assumed that the remote terminal 5 is not connected to the ground. At this time, the switching transistor Tr1
Is turned on because a current is supplied from the current supply resistor R. Then, the power control signal 4 becomes the ground level, the DC / DC converter 1 is turned on, and the potential is output to the system power supply 3. On the other hand, when the remote terminal 5 is externally connected to the ground level, no current is supplied to the switching transistor Tr1, and the switching transistor Tr1 is turned off. Then, the power supply control signal 4 becomes high level due to the power supply resistance R1 and the DC / DC converter 1 is turned off, so that no potential is output to the system power supply 3.

As described above, in the power supply control device of the first embodiment, the power supply of the terminal device is automatically turned on when the external power supply 2 is supplied, without connecting the remote terminal 5 to the ground level outside the terminal device. State.

(Embodiment 2) FIG. 2 is a configuration diagram of a power supply control device according to Embodiment 2 of the present invention.

In FIG. 2, 1 is a DC / DC converter, 2 is an external power supply, 3 is a system power supply, 4 is a power control signal, 5 is a remote terminal, R is a current supply resistor, R1 is a power supply resistor, Tr1 Are switching transistors, which have the same functions as those of the same reference numerals in the power supply control device of the first embodiment shown in FIG.

The features of the power supply control device according to the second embodiment are as follows.
There is provided a switching device 6 that allows a user to arbitrarily select a logical level of remote control. A and B are terminals of the switching device 6, which can be set arbitrarily by the user.

Next, the operation of the power supply control device of the second embodiment having the above configuration will be described.

When the terminal of the switching device 6 is connected to the A side, the system power supply 3 is initially set as in the conventional power supply control device.
Is turned on only when the external remote terminal 5 is connected to the ground without being turned on. On the other hand, when the terminal of the switching device 6 is connected to the B side, it functions in the same manner as in the first embodiment. Therefore, the user can freely change the initial state according to the situation.

[0023]

As is apparent from the above description, the present invention relates to a terminal for using a DC / DC converter capable of controlling output as a power supply, and a current supply resistor for taking in current from an external power supply and its initial state. And a remote terminal that is a remote control signal that can be extracted to the outside of the device as an input signal of the switching transistor. The power can be supplied to the target terminal device in the initial state in which the terminal is turned on, and the terminal can be turned on without any external connection work.

In addition, by providing a switching device that allows the user to arbitrarily select the logical level of the remote control, it is possible to determine whether the power of the terminal is turned on or off with the remote terminal of the terminal released. Can be set by the user.

Therefore, there is an effect that the connection work does not occur when the power is turned on as in the prior art, and the control is facilitated.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a power supply control device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a power supply control device according to a second embodiment of the present invention.

FIG. 3 is a configuration diagram of a conventional power supply control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 DC / DC converter 2 External power supply 3 System power supply 4 Power supply control signal 5 Remote terminal 6 Switching device Tr1 Switching transistor R Current supply resistance R1 Power supply resistance

Claims (2)

[Claims] 1. A terminal device using a DC / DC converter capable of controlling output as a power supply, a current supply resistor for taking in current from an external power supply, a switching transistor, and an external signal of the device as an input signal of the switching transistor. It is provided with a remote terminal that can be pulled out to the switching transistor in an initial state by a current supply resistor to turn on the switching transistor, and connecting the remote terminal to a ground level externally to turn the switching transistor off. Characteristic power supply control device. 2. The power supply control device according to claim 1, further comprising a switching device that allows a user to arbitrarily select a logical level of the remote control.