JPH0816275A - Power saving type computer - Google Patents

Abstract

PURPOSE:To stop a clock instead of disconnecting a power supply and to save power for an undriven circuit by generating/stopping a clock signal from a clock generating part to a peripheral control part while interlocking with the ON/OFF of the power supply to a peripheral device by a power supply switching part. CONSTITUTION:A peripheral power supply switching circuit 31 and a peripheral clock switching circuit 41 respectively turn on/off power supply to a floppy disk drive 1 and the supply of a clock signal to a floppy control circuit 2 based upon respective instructions from a control program 11. When the program 11 turns on/off a flip flop, an MOSFET is turned on/off. A clock signal is similarly turned on/off in accordance with the ON/OFF of the flip flop by the program 11. Thereby the program 11 can execute interlocking control between the ON/OFF of the power supply for the drive 1 and the ON/OFF of the clock signal to the circuit 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power saving system for a portable computer such as a notebook computer. It is necessary to reduce unnecessary power consumption as much as possible so that a notebook computer or the like can operate for a long time with a limited battery.

[0002]

2. Description of the Related Art FIG. 3 is a conceptual diagram of power supply of a conventional power-saving computer (notebook computer). The computer includes a power supply unit 3, a main body unit 10 including a processor, a memory, a display device which is a minimum input / output device, a keyboard, etc., a peripheral control unit 2, and a peripheral device (floppy disk drive) 1. Consists of Here, since the peripheral device 1 is not always necessary, the power supply is cut off when it is not necessary to operate the peripheral device 1 for power saving. Also, it may be configured as an external device structurally.

Whether or not to use the peripheral device 1 is determined by the control program 11 in response to an operator's instruction from the keyboard or by making an independent judgment. The peripheral power switch circuit 31 of the power supply unit 3 turns on / off the power of the peripheral device 1 according to an instruction from the control program 11 in the main body unit 10. In this case, the power supply unit 3 supplies power to the peripheral control unit 2 that controls the peripheral device 1, even if the power supply to the peripheral device 1 is cut off. When the peripheral device 1 does not operate, the peripheral control unit 2 also does not operate. However, since the peripheral control unit 2 updates and holds various control information for operating the peripheral device 1 correctly, This is because if the peripheral control unit 2 is also turned off when the power is turned off, the information is lost and the peripheral device 1 cannot be operated normally when it is necessary to operate it. In addition, it is difficult to separate the power source when the electronic circuit is an LSI circuit that is integrated with other circuits of the main body.

[0004]

Therefore, there is a problem in that the peripheral controller 2 consumes power even when it is not operating.

An object of the present invention is to save power in a circuit that is not operating by stopping the clock instead of cutting off the power supply.

[0006]

FIG. 1 is a diagram illustrating the principle of the present invention. The computer has a peripheral power supply switch unit 31 for controlling power on / off of the power supply unit 3 to the peripheral device 1.

The clock generator 4 is interlocked with the power-on / off of the peripheral device 1 by the peripheral power switch 31.
A peripheral clock switch unit 41 for supplying / stopping a clock signal from the peripheral control unit 2 to the peripheral control unit 2 is provided.

In order to control the turning on / off of the power supply to the peripheral device 1 and the supply of the clock signal to the peripheral control unit 2, the control program 11 causes the peripheral power supply switch unit 31 and the peripheral clock switch unit 41 to operate. It may be performed by operating.

[0009]

Therefore, when the power supply to the peripheral device 1 is stopped, the clock signal to the peripheral controller 2 is also stopped. As a result, the power consumption of the peripheral controller 2 can be reduced.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a block diagram of an embodiment of the present invention. The same functions as those in FIG. 1 are designated by the same reference numerals. The peripheral device is a floppy disk drive 1, and the peripheral control unit is a floppy control circuit 2.

The peripheral power supply switch circuit 31 and the peripheral clock switch circuit 41 are controlled by an instruction from the control program.
The power supply to the floppy disk drive 1 and the clock signal to the floppy control circuit 2 are turned on respectively.
N / OFF.

The peripheral power supply switch circuit 31 may be composed of a flip-flop, a power MOSFET, and a circuit for giving a signal from the flip-flop to its control input. Power to the floppy disk drive 1 is supplied through a MOSFET. The control program 11 turns on / off the flip-flop to turn on / off the MOSFET.
FF. Further, the peripheral clock switch circuit 41 may be similarly composed of an AND gate and a flip-flop which gives a signal to one terminal thereof. The clock signal of the floppy control circuit 2 is supplied through an AND gate. The control program 11 turns on / off the clock signal by turning on / off the flip-flop. Therefore, the control program 11 can control ON / OFF of the power supply of the floppy disk drive 1 and ON / OFF of the clock signal of the floppy control circuit 2.

When the LSI circuit is integrated with other circuits, the clock signal system of the floppy control circuit 2 needs to be separated from the clock signal system of the other circuits, but the power supply is separated. Unlike, it is easy to separate the clock signal system.

Most of the logic circuits of power-saving devices such as notebook personal computers are CMOS circuits, and the floppy control circuit 2 is also made of CMOS, so that power consumption is almost zero if the clock signal is stopped. Therefore, there is almost the same effect as turning off the power. Even if the clock signal is stopped, the contents held in the memory element in the circuit are not erased, so that the operation can be restarted immediately by applying the clock.

[0015]

As described above, according to the present invention,
When the peripheral device does not operate, the power supply of the peripheral device and the clock of its control circuit are cut off together, so that a power-saving computer with reduced power consumption can be realized.

[Brief description of drawings]

[Figure 1] Principle explanation diagram

FIG. 2 is a configuration diagram of an embodiment.

FIG. 3 is a conceptual diagram of conventional power supply.

[Explanation of symbols]

 1 Peripheral device (floppy disk drive) 2 Peripheral control unit (floppy control circuit) 3 Power supply unit 31 Peripheral power supply switch unit 4 Clock generation unit 41 Peripheral clock switch unit 10 Main body unit 11 Control program

Claims (1)

[Claims] 1. A computer having a peripheral power switch unit for controlling power on / off from a power unit to a peripheral device, the computer being interlocked with the power on / off of the peripheral device by the peripheral power switch unit. A power-saving computer having a peripheral clock switch unit for supplying / stopping a clock signal from the clock generation unit to the peripheral control unit.