JPH08221147A - Document preparation device - Google Patents

Abstract

PURPOSE: To suppress the peak value of the current consumption of the whole device small and reduce the size of the power circuit in the device by reducing the current consumption of circuits other than a motor when the current consumption becomes temporarily large at the start of motor driving. CONSTITUTION: When a user tries to save a document on an FDD 5, a CPU 2 outputs a spindle motor start instruction to an operation mode control circuit 1 first. The operation mode control circuit 1 once receiving the spindle motor start instruction stops the clock of the CPU 2 and places a DRAM 4 in self- refresh mode, and then outputs the spindle motor start signal to the FDD 5. When the power consumption becomes small after a spindle motor start current flows to the FDD 5, a mode current detecting circuit 6 detects the current state and outputs a detection signal to the operation mode control circuit 1. The operation mode control part 1 once receiving the current state detection signal resets the clock supply stop state of the CPU 2 and places the CPU 2 in operation again.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document preparation apparatus having an improved function of controlling current consumption.

[0002]

2. Description of the Related Art Conventionally, in a document preparation apparatus having a device using a motor such as a floppy disk device (FDD) or a printer device (PRT), a peak current is generated when the motor is started.

Normally, the power source of the FDD or PRT is common to the power source of the control circuit provided in the main body of the document creation apparatus, so that the power source device for supplying the power source is the power consumption of the FDD / PRT and the control circuit. Output capacity is required for the sum.

Therefore, as the output capacity of the power supply, "peak current at motor startup" + "current consumption of internal control circuit"
I needed only for that. At this time, generally, the current consumption at the time of starting the motor accounts for a large proportion of the current consumption of the entire device.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The motor startup of the D / PRT occurs for a short time when the document is stored or read by the document creation device, but the capacity of the power supply device must also support the peak current at the motor startup. Therefore, since the peak current value at the time of starting the motor is usually much larger than the power consumption value of the internal control circuit, there is a problem in that the power supply circuit becomes large, which causes the device to become large and heavy. It was

The present invention has been made in consideration of the above circumstances, and solves the above problems, and when a device having a motor such as an FDD has a temporary increase in current consumption at the time of starting the motor, a device other than the motor is used. An object of the present invention is to provide a document creation apparatus in which the peak value of the current consumption of the entire apparatus is suppressed to a low level by reducing the circuit current consumption, and the power supply circuit is downsized.

[0007]

In order to achieve the above-mentioned object, the present invention provides a current detecting means for detecting a current flowing through a motor of a device in a document preparation apparatus having a device having a motor therein. , A current reducing means for reducing current consumption of the control circuit provided therein, and when the current detecting means detects that a current of a predetermined value or more flows through the motor of the device, the current detecting means causes the current detecting means of the control circuit to operate. It is characterized in that control is performed so as to reduce current consumption.

Further, in order to achieve the above object, the present invention provides:
In a document preparation apparatus having a device having a motor installed therein, time storage means for storing a time from when the motor of the device is started to when a starting current flows through the motor, and current consumption of an internal control circuit Is provided to reduce the current consumption of the control circuit while the starting current is flowing through the motor of the device.

Further, in order to achieve the above-mentioned object, the present invention is such that, in the above-mentioned document preparation apparatus, the operating clock of the central control processing unit is stopped while the starting current is flowing to the motor of the device provided therein. Alternatively, it is characterized in that the frequency is controlled so that the current consumption of the control circuit is reduced.

[0010]

In the above construction, when the device having the motor starts the motor and the current consumption temporarily increases,
By reducing the current consumption of circuits other than the motor,
The peak value of current consumption of the entire device can be suppressed to a small value. As a result, the power supply circuit in the device can be downsized, and the device can be reduced in size and weight.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration relating to a main part of the invention in a document creating apparatus according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes an operation mode control circuit, which is a circuit for controlling the clock speed of the central control processing unit (CPU) 2 and the DRAM 4 and the refresh mode.

Reference numeral 2 is the central control processing unit (CPU) described above.
And is a microprocessor that controls the entire apparatus. Further, the CPU 1 has a control function of performing kana-kanji conversion sentence control processing on reading information from an input device (not shown) to create a kana-kanji mixture sentence and outputting the conversion result to the kana-kanji mixture sentence.

Reference numeral 3 is a ROM, which is a memory for storing various program information for the CPU 2 to operate. Reference numeral 4 denotes the above-mentioned DRAM, which is a memory for storing a document created by the user.

Reference numeral 5 denotes a floppy disk device (FDD) exemplified as a device having a motor therein, which is an external storage device for reading / writing a created document. In addition to the FDD, for example, a printer (PR
T), a hard disk device (HDD), and the like.

Reference numeral 6 denotes a motor current detection circuit, which is an FDD 5
It is a circuit that detects whether or not the peak current at the time of startup is flowing to the motor. In addition to the above-described components, a display device, a printer device as a device having a motor therein, and the like are provided, though not shown.

FIG. 2 is a diagram conceptually showing the current consumption of each of the above-mentioned parts in the embodiment of the present invention. When a large current flows temporarily (a) such as when the motor is on or seeking, CP is
The current consumption of U2 and DRAM 4 is kept low (b), and the peak value of the current consumption of the entire device is kept small (c).

2A shows the current consumption state including the seek operation of the FDD 5, and FIG. 2B shows the CPU.
2 and the state of the current consumption suppression control of the DRAM 4,
FIG. 7C shows the current consumption state (a + b) of the entire device.

The operation of the document creating apparatus having the above configuration will be described with reference to FIG. While the user is creating a document, the operation mode control circuit 1 supplies a clock to the CPU 2 and the DRAM 4 is in a normal operation mode (see FIG. 2B).

Next, when the user tries to save a document in the FDD 5, the CPU 2 first causes the operation mode control circuit 1 to operate.
The spindle motor start command is output to. When the operation mode control circuit 1 receives the spindle motor start command, it stops the clock of the CPU 2 and puts the DRAM 4 in the self-refresh mode (see FIG. 2B).
Output the spindle motor start signal to FDD5.

Then, when the consumption current becomes small after the spindle motor start-up current flows through the FDD 5 (FIG. 2A).
The motor current detection circuit 6 detects the current state and outputs the detection signal to the operation mode control circuit 1.

When the operation mode control circuit 1 receives the above-mentioned current state detection signal from the motor current detection circuit 6, the CPU 2
Reset the clock. That is, the clock supply stop state of the CPU 2 is released and the CPU 2 is operated again (see FIG. 2).
(B)).

After that, when a seek command is output from the CPU 2 to the FDD 5, the operation mode control circuit 1 again returns the C command.
The clock of PU2 is stopped and a seek instruction is output to FDD5.

After the seek current flows through the FDD 5, when the consumption current becomes small (see FIG. 2A), the motor current detection circuit 6 detects it and outputs the detection signal to the operation mode control circuit 1. After that, the operation mode control circuit 1
The clock of the CPU 2 is restored and the DRAM 4 is returned to the normal operation mode. Then, the document created by the user is FD
Write to a floppy disk (FD) which is a recording medium of D5.

By performing the above control operation, the peak value of the current consumption of the entire device can be suppressed to a low value, and the power supply circuit can be downsized. That is, in the conventional case, as shown in FIG.
The peak current during seek shown in (a) had to have a power supply circuit function capable of supplying a current in which the normal circuit current shown in FIG. According to the example, the current consumption of the CPU 2 and the DRAM 4 becomes small when a large current temporarily flows, such as when the motor is turned on or when the seek operation is performed. Can be realized.

In the above-described embodiment, the motor current detection circuit detects the spindle motor starting current / seek current. However, the time during which the spindle motor starting current / seek current flows is measured in advance, and a fixed time is determined. While C
It is also possible to stop the PU clock and put the DRAM in the self-refresh mode.

Further, in the above-mentioned embodiment, the FDD of the document creating apparatus is taken as an example of the device having the motor, but for example, a small electronic device such as a personal computer or an HD.
Of course, it can be applied to devices using motors such as D and printers.

[0028]

As described above in detail, according to the present invention, F
When the current consumption temporarily increases at the time of starting the motor such as DD, the peak value of the current consumption can be kept low by reducing the current consumption of circuits other than the motor, thereby reducing the load on the power supply circuit. This has the effect of making it lighter and making the power supply circuit smaller and lighter.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an exemplary embodiment of the present invention.

FIG. 2 is a view conceptually showing a state of current consumption in the embodiment.

[Explanation of symbols]

1 ... Operation mode control circuit, 2 ... CPU, 3 ... ROM, 4
... DRAM, 5 ... FDD, 6 ... Motor current detection circuit.

Claims (3)

[Claims] 1. A document creation apparatus having a device having a motor therein, wherein current detecting means for detecting a current flowing through the motor of the device, and current reducing means for reducing current consumption of a control circuit provided therein. And a current detecting means detects that a current of a predetermined value or more flows through the motor of the device, the current detecting means controls the current consumption of the control circuit to be reduced. Creation device. 2. A document creating apparatus having a device having a motor therein, time storing means for storing a time from a time when the motor of the device is started to a time when a starting current flows through the motor, the time storing means being provided internally. A document creating apparatus, comprising: a current reducing unit that reduces current consumption of a control circuit, and performing control so as to reduce current consumption of the control circuit while a starting current is flowing to a motor of the device. 3. While the starting current is flowing to the motor of the internal device, the operation clock of the central control processing unit is stopped or the frequency is lowered to control the current consumption of the control circuit. Claim 1 or 2 characterized by
Document creation device described.