JPH04355811A - Input/output interface control circuit - Google Patents

Abstract

PURPOSE:To supply power only in the case of connecting a connector but to completely eliminate the power consumption otherwise by adding a power pin through which power is supplied to a circuit, to the connector of a signal line to an input/output control integrated circuit. CONSTITUTION:A connector 2 is provided with two short-circuited power pins 32 connected to a power line 31 from a power source 3 besides signal pins 52 connected to a signal line 5 to an IC 1. If there is an input/output apparatus, the connector 2 is connected; and when the power source of the device is turned on, power is supplied to the IC 1 also from the power source 3 through the power line 31 and power pins 32, and the input/output apparatus is connected to a bus line 6 of the device through signal pins 52 of the connector 2, the signal line 5, the IC 1, and a signal line 4. If there is not any input/output output apparatus, the connector 2 is removed to break the power supply from the power source 3 to the IC 1. Consequently, signal lines 4 and 5 are meaningless, and it does not matter even if power of the IC 1 is cut off, and it is disconnected from the bus line 6 of the device.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an input/output interface control circuit, and more particularly to an input/output interface control circuit for an information processing device with low power consumption.

0002

2. Description of the Related Art As shown in FIG. 2, a conventional input/output interface control circuit is an integrated circuit for input/output control (hereinafter, IC
) 1 was connected to the bus line 6 of the device via the signal line 4, and an input/output device (not shown) was connected to the signal line 5 of this IC 1 via the signal pin 52 of the connector 21. . Power is always supplied to the IC 1 from the power supply 3, and a constant amount of power is always consumed even when no input/output equipment is connected, that is, when the connector 21 is not connected.

0003

[Problems to be Solved by the Invention] The conventional input/output interface control circuit described above constantly supplies power to the IC regardless of whether input/output devices are connected. always consumes a certain amount of power, which is a big problem in devices such as battery-powered information processing devices that need to use batteries as efficiently as possible to extend battery life as much as possible.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an input/output interface control circuit that can suppress wasteful power consumption in an IC.

[0005]

[Means for Solving the Problems] An input/output interface control circuit of the present invention has a connector equipped with a signal pin and a power pin for supplying signals and power to an input/output control integrated circuit, respectively, and the connector has a Power is supplied to the integrated circuit only when it is connected, and power is cut off to the integrated circuit when the connector is not connected, reducing power consumption to zero.
It is characterized by making it.

[0006]

Embodiments Next, embodiments of the present invention will be explained with reference to the drawings.

Referring to FIG. 1, in one embodiment of the present invention, the connector 2 includes a power line 3 that supplies power to the IC 1 from a power source 3 in addition to a signal pin 52 that connects to a signal line 5 to the IC 1.
1 is used, which has two shorted power supply pins 32 connected to 1. The other configurations are the same as the conventional example shown in FIG.

If there is an input/output device, the connector 2 is connected, and when the device is turned on, the power line 31 is connected from the power source 3.
Power is also supplied to the IC1 via the power pin 32 of the connector 2, and the input/output device is the signal pin 5 of the connector 2.
2. Connected to the bus line 6 of the device via the signal line 5, IC1, and signal line 4.

[0009] If there is no input/output device, disconnecting the connector 2 cuts off the power supply from the power supply 3 to the IC 1, and the power consumption of the IC 1 becomes 0. At this time, signal line 4,
5 is meaningless since there is no input/output device, and IC
Even if the power to the device 1 is cut off, the device remains disconnected from the bus line 6 without any problem.

0010

Effects of the Invention As explained above, the present invention adds a power pin 32 to the connector 2 that connects to the power line 31 from the power source 3 of the IC 1, and supplies the power 3 to the IC 1 via the connector 2. This has the effect that power supply to the IC 1 can be automatically stopped when no input/output equipment is connected, and unnecessary power consumption can be reduced to zero.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of one embodiment of the present invention.

FIG. 2 is a block diagram of a conventional example.

[Explanation of symbols]

1 Integrated circuit for input/output control 2, 21 Connector 3 Power supply 4 Signal line 5 for connecting to the bus line of the device
Signal line 6 connected to integrated circuit 1 via connector Device bus line

Claims (1)

[Claims] Claim 1: In an input/output interface control circuit comprising a connector having a signal connection means for connecting an input/output device to a signal line of an input/output control integrated circuit, when the connector is connected to the signal line. An input/output interface control circuit characterized in that the connector is provided with a power supply connection means for connecting the power supply line of the input/output control integrated circuit to a power supply.