JP2004054560A - Power source managing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely execute each operation even when the transition of a normal mode to a power saving mode and the transition of the power saving mode to the normal mode are overlapped in the same period when supplying a power to electric equipment, and to prevent the unstable situations of a power supply voltage such as a voltage drop. <P>SOLUTION: Even when a shut down signal and a restoration signal are generated in the same period, the restoration signal is held by a CPLD, and a restoration operation is started after a power source interrupting operation based on the shut down signal is completely ended. Thus, it is possible to prevent a high speed on/off operation in an LVPS, and to prevent the deterioration of a life time. Also, the voltage drop due to the high speed on/off operation is not generated so that unstable power can be prevented from being supplied to a printer control circuit, and that a malfunction can be prevented from being generated. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a power supply management device that manages a power supply for supplying power to an electric device.
[0002]
Problems to be solved by the prior art and the invention
A power management device for supplying power to an electric device has a function of automatically (or manually) shifting to a power saving mode for supplying a minimum necessary power when the electric device does not operate for a predetermined time. ing. As a result, unnecessary power consumption is reduced, and resources can be saved.
[0003]
The electric device in the power saving mode can start up in the normal mode when a return signal is input by the user.
[0004]
In the conventional electric equipment, even in the power saving mode, the power supply to the mounted CPU or the like is continued and the return signal is monitored, and the operation of shifting to the power saving mode and the operation of returning to the normal mode are performed. Management and control can be performed so that they do not overlap in time.
[0005]
However, continuing to supply power to the printer control circuit of the electric device in the power saving mode is contrary to the original purpose of the power saving mode of reducing power consumption. (System down).
[0006]
In such a case, if a return signal is input at the same time as the start of the transition to the power saving mode, the return operation starts in the middle of power-off, and the power source (low On the voltage power supply (LVPS) side, high-speed control from system down to recovery is performed.
[0007]
That is, since the input of the return signal is based on the user's intention as described above, it is completely asynchronous with the transition time of the power saving mode, and there is a possibility that the conflicting instructions as described above may overlap. .
[0008]
However, a general LVPS cannot respond to a high-speed pulse, and the power supply voltage becomes unstable during high-speed control from system down to recovery as described above. For example, a voltage drop occurs and the system malfunctions. And the life of the LVPS itself due to high-speed power on / off is reduced.
[0009]
In consideration of the above facts, the present invention, when supplying power to the electric device, performs each operation even when the transition from the normal mode to the power saving mode and the transition from the power saving mode to the normal mode overlap at the same time. An object of the present invention is to provide a power management device that can be executed reliably and can prevent an unstable situation of a power supply voltage such as a voltage drop.
[0010]
[Means for Solving the Problems]
The present invention is a power management device that manages a power supply for supplying power to an electric device, and switches a power supply to the electric device from a normal mode to a power saving mode that cuts off unnecessary power supply at a predetermined timing. Power saving control means for switching, monitoring means for monitoring the presence / absence of a return signal for returning the electric device from the power saving mode to the normal mode, and power saving when the monitoring means detects the input of the return signal. Return control means for switching from a mode to a normal mode, when switching to the power saving mode by the power supply control means, and when detection of the input of a return signal by the monitoring means occurs at about the same time, A switching operation control unit configured to execute switching to the normal mode by the return control unit after the switching to the power saving mode is completed by the power saving control unit.
[0011]
According to the present invention, the power saving control means starts the operation of switching the power supply to the electric device from the normal mode to the power saving mode for cutting off unnecessary power supply at a predetermined opportunity.
[0012]
On the other hand, when the input of the return signal is detected by the monitoring means, the return control means starts the operation of switching from the power saving mode to the normal mode.
[0013]
The above two operations (normal mode → power saving mode switching operation and power saving mode → normal mode switching operation) are contradictory operations. If these operations occur at the same time, the power supply voltage becomes unstable or the respective controls are not performed. In some cases, malfunctions of electrical equipment, such as high-speed execution, and shortening of the life of the power management device itself may occur.
[0014]
Therefore, in the switching operation control means, when the detection of the input of the return signal by the monitoring means occurs at about the same time, the switching operation control means waits for the end of the switching to the power saving mode by the power saving control means, and the return control means Switching to the normal mode is now performed. Thereby, since the respective opposing operations are executed in a time series, the above-mentioned problem can be solved.
[0015]
Further, in the present invention, the power management device is controlled by a small-scale programmable device that is not involved in controlling the printer control circuit on the electric device side.
[0016]
That is, since there is no need to manage the power in the printer control circuit on the electric device side, it is possible to sufficiently reduce the power consumption inherent in the power saving mode.
[0017]
Furthermore, in the present invention, the power saving mode is characterized in that power is supplied to an element including the small-scale programmable device and functioning as the power management device.
[0018]
In the power saving mode, power needs to be supplied only to the power management device (mainly, a small-scale programmable device), so that power saving in the power saving mode can be effectively executed.
[0019]
Further, in the present invention, the switching operation control means includes a timer for measuring a predetermined time from the start of the switching to the power saving mode, and executes the switching to the normal mode by the return control means after a lapse of a predetermined time by the timer. It is characterized by:
[0020]
With a simple device configuration in which the input signal of the return signal is delayed by the timer, conflicting operations in the same period can be avoided.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows a printer system 10 capable of executing printer control according to the present embodiment. This printer system 10 includes, for example, a plurality of PCs (personal computers) 12 as print instruction devices disposed on desks of a plurality of users who work in an office, and a plurality of printers 14 distributed to each part of the office. These are connected by a network 16 such as a LAN (local area network).
[0022]
FIG. 2 is a control block diagram of the printer 14. The printer controller 18 is connected with an exposure scanning system control unit 20, a transport system control unit 22, a development processing system control unit 24, and a fixing processing system control unit 26, and an operation control signal from a printer control circuit 30 is sent to each unit. Sending out.
[0023]
The printer control circuit 30 is supplied with stabilized operating power of a predetermined voltage (for example, 3.3 V) from an LVPS (low voltage power supply) 32.
[0024]
The power supply of the LVPS 32 is controlled by a power management device 34. That is, in the power management device 34, the operation of the LVPS 32 is controlled, and the printer 14 operates as a normal mode in which power is supplied to all the control units including the printer control circuit 30; The power saving mode can be selectively switched to a power saving mode in which the power to all the control units is cut off and the power saving state is set.
[0025]
The power management device 34 includes a small-scale programmable device (CPLD) 36 that can continue to operate in either the normal mode or the power saving mode. A shutdown signal is input to the CPLD 36 from the printer control circuit 30 at a predetermined timing. The operation of the CPLD 36 is continued by the clock 38.
[0026]
When this shutdown signal is input to the CPLD 36, the CPLD 36 sends a remote-off signal to the LVPS 32, and the power supply control of the LVPS 32 to the printer control circuit 30 is cut off (power saving mode).
[0027]
The power management device 34 includes a network IC 40 for receiving a signal from the network 16. When the PC 12 connected to the network 16 issues a printer operation instruction according to a user's intention, the network IC 40 sends a signal to the CPLD 36. Thus, a return signal is transmitted.
[0028]
The CPLD 36 outputs a remote-on signal to the LVPS 32 based on the input of the return signal, and controls power supply to the printer control circuit 30 in the LVPS 32 (normal mode).
[0029]
Further, a timer 42 is connected to the CPLD 36. The timer 42 is reset and started by the input of the shutdown signal, and counts a predetermined time.
[0030]
During the counting by the timer (during the predetermined time), the CPLD 36 holds the return signal input from the network IC 40.
[0031]
That is, even when the shutdown signal and the return signal are input to the CPLD 36 at the same time, the output operation of the remote-off signal and the remote-on signal to the LVPS 32 can be substantially executed with a time lag. It becomes possible.
[0032]
The operation of the present embodiment will be described below.
[0033]
In the normal mode, power of a predetermined power supply voltage is supplied from the LVPS 32 to the printer control circuit 30, and power is supplied from the power supply device 34 to each control unit controlled by the printer control circuit 30.
[0034]
When the printer 14 is in the operation standby state for a predetermined time, the printer control circuit 30 sends a shutdown signal to the CPLD 36. As a result, the CPLD 36 sends a remote-off signal to the LVPS 32, and shuts off the power supply from the LVPS 32 to the printer control circuit 30, thereby shutting off all power to the entire printer 14 (power saving mode).
[0035]
On the other hand, when there is a print operation instruction from the PC 12 via the network 16, a return signal is input from the network IC 40 to the CPLD 36. The CPLD 36 outputs a remote-on signal to the LVPS 32 based on the return signal.
[0036]
This allows the LVPS 32 to supply power to the printer control circuit 30 and start up the printer 14 (normal mode).
[0037]
Here, the switching operation from the normal mode to the power saving mode by the shutdown signal and the switching operation from the power saving mode to the normal mode by the return signal are asynchronous because the return signal depends on the user's intention. For this reason, there is a possibility that both operations occur by coincidence.
[0038]
When such contradictory switching operations occur at the same time, high-speed processing is performed by the LVPS 32, the life of the LVPS 32 is shortened due to the high-speed ON / OFF operation, the voltage drop of the power supplied to the printer control circuit 30, and the like. May cause the printer control circuit 30 to malfunction.
[0039]
Therefore, in the present embodiment, a timer 42 is added to the CPLD 36, the return signal input to the CPLD 36 is held during the time measured by the timer 42 (predetermined time), and the completion of the switching operation to the power saving mode by the shutdown signal is completed. After waiting, the switching operation to the normal mode by the return signal is executed.
[0040]
Hereinafter, the switching operation will be described with reference to the flowchart of FIG. 3 and the timing chart of FIG.
[0041]
In step 100 of FIG. 3, it is determined whether or not a shutdown signal has been input. If an affirmative determination is made (see (1) in FIG. 4), the process proceeds to step 102 to reset / start the timer 42 (see FIG. 4). (2)).
[0042]
In the next step 104, a remote-off signal is output to the LVPS 32 (see (3) in FIG. 4). As a result, the power supply to the printer control circuit 30 of the printer 14 is cut off, and at the same time, the power supply from the power supply unit 34 to all the control units is cut off. In order to completely shut off the power supply, a certain time t (see a range t in FIG. 4) is required.
[0043]
In the next step 106, it is determined whether or not a return signal has been input. If an affirmative determination is made (see (4) in FIG. 4), the return signal is held in the CPLD 36 in step 108, and the process proceeds to step 110. .
[0044]
Since the timing of the affirmative determination in the step 106 depends on the user's intention, in addition to the position of (4) in FIG. 4, the timing indicated by a chain line ([4] 'in FIG. 4) or a two-dot chain line (See “4” in FIG. 4).
[0045]
In step 110, it is determined whether or not the time measurement by the timer 42 has elapsed for a predetermined time (whether or not a threshold has been exceeded). If a negative determination is made, the holding of the return signal is continued.
[0046]
If an affirmative determination is made in step 110, a remote-on signal is sent to the LVPS 32 based on the return signal (see (5) in FIG. 4). As a result, the printer control circuit 30 of the printer 14 is activated, and power is supplied to all control units (normal mode).
[0047]
That is, the time measured by the timer 42 is set to a time slightly longer than the time t for the power supply cutoff, and even if a return signal is input from the start of the power supply cutoff to the complete cutoff, Do not immediately perform a return operation (output a remote-on signal). As a result, the remote-off signal and the remote-on signal are not input to the LVPS 32 at the same time, the power supply can be stably shut off and the power supply can be restored, and the printer control circuit 30 does not malfunction.
[0048]
As described above, in the present embodiment, when the printer control circuit 30 is completely turned off in the power saving mode, even if the shutdown signal and the return signal occur at the same time, the return signal is held by the CPLD 36, Since the return operation is started after the power cutoff operation based on the shutdown signal is completely terminated, the high-speed on / off operation of the LVPS 32 is eliminated, and a reduction in the life can be avoided. Further, since a voltage drop or the like due to the high-speed on / off operation does not occur, unstable power is not supplied to the printer control circuit 30 and no malfunction occurs.
[0049]
In the present embodiment, the printer 14 has been described as an example of the electrical device that selectively switches between the normal mode and the power saving mode. However, power saving is effective in other OA devices such as facsimile machines and copiers, and in home appliances. It can be applied to all electrical devices.
[0050]
【The invention's effect】
As described above, in the present invention, when power is supplied to an electric device, even when the transition from the normal mode to the power saving mode and the transition from the power saving mode to the normal mode overlap at the same time, each operation is reliably performed. The present embodiment has an excellent effect of preventing an unstable situation of the power supply voltage such as a voltage drop.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a printer system according to an embodiment.
FIG. 2 is a control block diagram of a printer including the power management device according to the present embodiment.
FIG. 3 is a flowchart showing a power management control routine in the CPLD of the power management device according to the present embodiment.
FIG. 4
6 is a time chart at the time of power management control.
[Explanation of symbols]
10 Printer system 12 PC
14 Printer 16 Network 18 Printer Controller 20 Exposure Scanning System Control Unit 22 Transport System Control Unit 24 Development Processing System Control Unit 26 Fixing Processing System Control Unit 30 Printer Control Circuit 32 LVPS
34 power management device 36 CPLD (power saving control means, monitoring means, return control means, switching operation control means)
38 Clock 40 Network IC
42 timer

Claims (4)

A power management device that manages a power supply for supplying power to an electric device,
Power saving control means for switching power supply to the electrical device at a predetermined opportunity from a normal mode to a power saving mode for cutting off unnecessary power supply,
Monitoring means for monitoring the presence or absence of a return signal for returning the electrical device from the power saving mode to the normal mode,
When the input of the return signal is detected by the monitoring means, return control means for switching from the power saving mode to the normal mode,
When the switching to the power saving mode by the power supply control unit and the detection of the input of the return signal by the monitoring unit occur almost at the same time, the switching to the power saving mode by the power saving control unit is completed. Switching operation control means for executing a switch to a normal mode by the return control means,
A power management device having: 2. The power management apparatus according to claim 1, wherein the power management apparatus is controlled by a small-scale programmable device that is not involved in CPU control of the electric device. The power management apparatus according to claim 2, wherein the power saving mode is power supply to an element including the small-scale programmable device and functioning as the power management apparatus. The switching operation control means includes a timer for measuring a predetermined time from the start of the switching to the power saving mode, and performs switching to the normal mode by the return control means after a lapse of a predetermined time by the timer. The power management device according to any one of claims 1 to 3.

Images