JP2022144094A - Information processing apparatus and power supply control method - Google Patents

Abstract

To provide an information processing apparatus and a power supply control method that, in a configuration allowing an increase in memory, can reduce power consumption in a power saving mode to a constant level or less and prevent extension of the recovery time from the power saving mode.SOLUTION: An image forming apparatus comprises: a detection processing unit that detects a supply current supplied to a DIMM 14 attached to a DIMM socket 13; and a power supply control unit that, when the operation mode of the image forming apparatus is switched from a normal mode to a power saving mode, if the supply current detected by the detection processing unit exceeds a predetermined reference value, saves data stored in the DIMM 14 in a flash memory 15 and stops the power supply to the DIMM 14, and if the supply current does not exceed the reference value, does not stop the power supply to the DIMM 14.SELECTED DRAWING: Figure 3

Description

The present invention relates to an information processing device and a power supply control method.

2. Description of the Related Art There is known an information processing apparatus such as a multi-function machine capable of adding memory (see, for example, Japanese Unexamined Patent Application Publication No. 2002-100001). In this type of information processing apparatus, the memory is optionally added by the user.

JP 2010-228331 A

By the way, the information processing apparatus is sometimes required to suppress the power consumption in the power saving mode to a certain level or less. Here, in the information processing apparatus in which the memory can be expanded, there are cases where the above request cannot be satisfied depending on the type of the memory that is expanded by the user. On the other hand, when the operation mode of the information processing device shifts to the power saving mode, the above request can be satisfied by saving the data in the added memory and stopping the power supply to the memory. It is possible. However, in this case, it takes a long time to return from the power saving mode to the normal mode.

SUMMARY OF THE INVENTION An object of the present invention is to provide an information processing apparatus capable of suppressing the power consumption in the power saving mode to a certain level or less and suppressing the lengthening of the recovery time from the power saving mode in a configuration in which memory can be expanded, and a power supply. It is to provide a control method.

An information processing device according to one aspect of the present invention includes a mounting section, a second memory, a detection processing section, and a power supply control section. A volatile first memory is mounted in the mounting portion. The second memory is non-volatile. The detection processing section detects a supply current supplied to the first memory attached to the attachment section. When the operation mode of the device is switched from a normal mode to a power saving mode that consumes less power than the normal mode, the power supply control unit sets the supply current detected by the detection processing unit to a predetermined reference value. When exceeding the reference value, the data stored in the first memory is saved in the second memory, the power supply to the first memory is stopped, and when the supply current does not exceed the reference value, the first memory power supply to the

A power supply control method according to another aspect of the present invention is executed by an information processing device comprising a mounting section to which a volatile first memory is mounted and a nonvolatile second memory, and comprises the following detection steps; and a power supply control step. In the detection step, a supply current supplied to the first memory attached to the attachment portion is detected. In the power supply control step, when the operation mode of the information processing device is switched from a normal mode to a power saving mode that consumes less power than the normal mode, the supply current detected by the detection step is a predetermined reference. When the value exceeds the reference value, the data stored in the first memory is saved in the second memory and the power supply to the first memory is stopped, and when the supply current does not exceed the reference value, the first memory power supply to the

According to the present invention, in a configuration in which a memory can be added, it is possible to suppress the power consumption in the power saving mode to a certain level or less, and to suppress the lengthening of the recovery time from the power saving mode.

FIG. 1 is a diagram showing the configuration of an image forming apparatus according to an embodiment of the invention. FIG. 2 is a block diagram showing the system configuration of the image forming apparatus according to the embodiment of the invention. FIG. 3 is a diagram showing the configuration of the control unit of the image forming apparatus according to the embodiment of the invention. FIG. 4 is a flow chart showing an example of identification information acquisition processing executed by the image forming apparatus according to the embodiment of the present invention. FIG. 5 is a flowchart showing an example of power supply control processing executed by the image forming apparatus according to the embodiment of the present invention. FIG. 6 is a flow chart showing an example of current detection processing executed by the image forming apparatus according to the embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. It should be noted that the following embodiment is an example that embodies the present invention, and does not limit the technical scope of the present invention.

[Configuration of Image Forming Apparatus 100]
First, the configuration of an image forming apparatus 100 according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. Here, FIG. 1 is a sectional view showing the configuration of the image forming apparatus 100. As shown in FIG.

The image forming apparatus 100 is a multifunction machine having a plurality of functions such as a scanning function for reading an image of a document, a printing function for forming an image on a sheet based on image data, a facsimile function, and a copying function. Image forming apparatus 100 is an example of an information processing apparatus of the present invention. The present invention may be applied to information processing devices such as scanners, printers, facsimile machines, copiers, personal computers, notebook computers, tablet terminals, and smart phones.

As shown in FIGS. 1 and 2, the image forming apparatus 100 includes an ADF (Auto Document Feeder) 1, an image reading section 2, an image forming section 3, a sheet conveying section 4, an operation display section 5, a power feeding section 6, and A control unit 7 is provided.

The ADF 1 conveys a document to be read by the scanning function. The ADF 1 includes a document set section, a plurality of transport rollers, a document presser, and a paper discharge section.

The image reading section 2 realizes the scanning function. The image reading unit 2 includes a platen, a light source, a plurality of mirrors, an optical lens, and a CCD (Charge Coupled Device).

The image forming section 3 realizes the printing function. Specifically, the image forming unit 3 forms an image by electrophotography. The image forming section 3 includes a photosensitive drum, a charging device, an optical scanning device (LSU), a developing device, a transfer device, a cleaning device, and a fixing device.

The sheet conveying section 4 conveys a sheet on which an image is formed by the image forming section 3 . The sheet conveying unit 4 includes a paper feed cassette and a plurality of conveying rollers.

The operation display unit 5 is a user interface of the image forming apparatus 100 . The operation display unit 5 includes a display unit such as a liquid crystal display for displaying various information according to control instructions from the control unit 7, and operation keys or a touch panel for inputting various information to the control unit 7 according to user operations. It has an operation part such as

Power supply unit 6 supplies power supplied from an external commercial power source to each unit of image forming apparatus 100 . Specifically, the power supply unit 6 is an AC-DC converter that converts an AC voltage of 100V supplied from the commercial power source into a DC voltage of a predetermined voltage value.

The control unit 7 controls the image forming apparatus 100 as a whole.

[Configuration of control unit 7]
Next, the configuration of the control unit 7 will be described with reference to FIGS. 2 and 3. FIG. Here, FIG. 3 is a plan view showing the configuration of the control board 20. As shown in FIG. In FIG. 3, control signals transmitted and received by the CPU 11 are indicated by dashed lines with arrows.

As shown in FIG. 3, the control unit 7 includes a CPU 11, a DRAM (Dynamic Random Access Memory) 12, a DIMM (Dual Inline Memory Module) socket 13, a DIMM 14, a flash memory 15, a power supply 16, a power supply path switching unit 17, a resistor 18, a current detection circuit 19, and a control board 20 on which these components are mounted.

The CPU 11 is a processor that executes various kinds of arithmetic processing. The CPU 11 executes various arithmetic processing by executing a control program stored in advance in a ROM (not shown) provided in the control section 7 .

For example, the CPU 11 functions as the switching processing unit 31 shown in FIG. 2 by executing the control program.

The switching processing unit 31 switches the operation mode of the image forming apparatus 100 between a normal mode and a power saving mode that consumes less power than the normal mode. In the power saving mode, power supply to some of the components of the image forming apparatus 100 is stopped.

Specifically, when the operation mode is the normal mode, the switching processing unit 31 switches the operation mode from the normal mode to the power saving mode when a predetermined transition condition is satisfied.

For example, the transition conditions include a first transition condition and a second transition condition. The switching processing unit 31 switches the operation mode to the power saving mode when either the first transition condition or the second transition condition is satisfied. The first transition condition is that a no-operation state in which no operation input is made to the image forming apparatus 100 continues beyond a predetermined time. The second shift condition is that an input operation of an instruction to shift to the power saving mode is performed on the operation display unit 5 . Note that the transition conditions may include conditions different from the conditions described above.

Further, when the operation mode is the power saving mode, the switching processing unit 31 switches the operation mode from the power saving mode to the normal mode when a predetermined recovery condition is satisfied.

For example, the return conditions include a first return condition and a second return condition. The switching processing unit 31 switches the operation mode to the normal mode when either the first return condition or the second return condition is satisfied. The first return condition is to receive an image forming job transmitted from an external information processing device. The second return condition is that the operation display section 5 is operated. Note that the return conditions may include conditions different from the conditions described above.

When switching the operation mode from the normal mode to the power saving mode, the switching processing unit 31 inputs a control signal (not shown) to that effect to the power supply unit 6 to switch the operation mode from the normal mode to the power saving mode. power supply to the part. Further, when switching the operation mode from the power saving mode to the normal mode, the switching processing unit 31 inputs a control signal (not shown) to that effect to the power supply unit 6 to switch the components of the image forming apparatus 100 . power supply to some of the

DRAM 12 is a volatile memory. The DRAM 12 is used as a temporary storage memory (work area) for various processes executed by the CPU 11 . DRAM 12 is an example of another first memory of the present invention.

The DRAM 12 can switch the operation mode between a first mode and a second mode that consumes less power than the first mode. The first mode is an operation mode in which data can be read and written. The second mode is an operation mode in which reading and writing of data is disabled and refresh operations are periodically performed to retain stored data. The second mode is called self-refresh mode. The DRAM 12 switches the operation mode between the first mode and the second mode according to the input of the control signal instructing the switching of the operation mode from the CPU 11 .

A DIMM 14 is attached to the DIMM socket 13 . The DIMM socket 13 is an example of the mounting portion of the present invention.

DIMM 14, like DRAM 12, is a volatile memory. DIMM 14 is attached to DIMM socket 13 . The DIMM 14 is a so-called expansion memory, which is added by the user of the image forming apparatus 100 after the image forming apparatus 100 is shipped. DIMM 14 is an example of the first memory of the present invention. Also, the DIMM 14 is an example of the specific memory of the present invention.

The DIMM 14, like the DRAM 12, can switch its operation mode between the first mode and the second mode. The DIMM 14 switches the operation mode between the first mode and the second mode according to the input of the control signal instructing switching of the operation mode from the CPU 11 .

The DIMM 14 has an SPD (Serial Presence Detect) storing specification data relating to the specification of the DIMM 14 . The specification data includes information such as the manufacturer's name, standard, capacity of the DIMM 14, information on the mounted DRAM, operating clock frequency, and operating voltage. The DIMM 14 reads the specification data from the SPD and transmits the read specification data to the CPU 11 in response to the input of the control signal instructing the reading of the specification data from the CPU 11 .

Flash memory 15 is a non-volatile memory. Setting information set by the user of the image forming apparatus 100 is stored in the flash memory 15 . Flash memory 15 is an example of the second memory of the present invention.

A power supply 16 supplies power to the DIMMs 14 attached to the DIMM sockets 13 . For example, the power supply 16 is a DC-DC converter that converts a DC voltage having a predetermined voltage value supplied from the power supply unit 6 into a drive voltage for the DIMMs 14 . Note that the power supply 16 may supply power to the DRAM 12 .

The power supply path switching unit 17 switches the power supply path from the power supply 16 to the DIMM socket 13 between the first power supply path and the second power supply path. The first feed path is a feed path that does not pass through the resistor 18 . Also, the second power supply path is a power supply path that passes through the resistor 18 .

As shown in FIG. 3, the power supply path switching unit 17 includes switches 17A and 17B.

The switch 17A can switch between conduction and interruption of the first power feeding path. For example, switch 17A is a semiconductor switch such as a transistor. A switch 17A is provided on the first power supply path. The switch 17A switches between conduction and interruption of the first power supply path in response to an input of a control signal for switching between conduction and interruption of the first power supply path from the CPU 11 .

The switch 17B can switch between conduction and interruption of the second power supply path. For example, switch 17B is a semiconductor switch such as a transistor. A switch 17B is provided on the second feed path. The switch 17B switches between conduction and interruption of the second power supply path in response to input of a control signal for switching between conduction and interruption of the second power supply path from the CPU 11 .

A resistor 18 is a resistor used to detect the current flowing through the second feed path.

The current detection circuit 19 is an electronic circuit that determines whether the voltage across the resistor 18 is higher than a predetermined reference voltage and outputs a control signal indicating the determination result to the CPU 11 . The current detection circuit 19 is driven by power supplied from a power supply (not shown). The current detection circuit 19 may be driven by power supplied from the power supply 16 via the switch 17B.

By the way, an information processing apparatus such as the image forming apparatus 100 may be required to suppress the power consumption in the power saving mode to a certain level or less. Here, in an information processing apparatus such as the image forming apparatus 100 in which a memory can be added, there are cases where the above requirements cannot be satisfied depending on the type of memory added by the user. On the other hand, when the operation mode of the information processing device shifts to the power saving mode, the above request can be satisfied by saving the data in the added memory and stopping the power supply to the memory. be. However, in this case, it takes a long time to return from the power saving mode to the normal mode.

On the other hand, in the image forming apparatus 100 according to the embodiment of the present invention, in a configuration in which a memory can be added, the power consumption in the power saving mode is suppressed to a certain level or less and It is possible to suppress the lengthening of the recovery time from the power saving mode.

Specifically, in the ROM of the control unit 7, a power supply control program for causing the CPU 11 to execute an identification information acquisition process (see the flowchart in FIG. 4) and a power supply control process (see the flowchart in FIG. 5) is stored in advance. stored. The power supply control program is recorded on a computer-readable recording medium such as a CD, DVD, or flash memory, and may be read from the recording medium and installed in a storage unit such as the flash memory 15 .

The control unit 7 includes an acquisition processing unit 32, a detection processing unit 33, and a power supply control unit 34, as shown in FIG. Specifically, the CPU 11 functions as an acquisition processing unit 32, a detection processing unit 33, and a power supply control unit 34 by executing the power supply control program stored in the ROM.

The acquisition processing unit 32 acquires the specification data from the DIMM 14 attached to the DIMM socket 13 each time a predetermined acquisition timing arrives. In the image forming apparatus 100, the DIMMs 14 attached to the DIMM sockets 13 are identified based on the specification data. The specification data is an example of identification information of the present invention.

Specifically, the acquisition timing is the timing when the image forming apparatus 100 is powered on. Note that the acquisition timing may be a timing that periodically arrives during operation of the image forming apparatus 100 .

For example, the acquisition processing unit 32 stores the acquired specification data in a predetermined first storage area in the flash memory 15 .

The detection processing unit 33 detects the supply current supplied to the DIMMs 14 attached to the DIMM sockets 13 .

Here, the supply current is the current supplied to the DIMM 14 operating in the second mode.

Specifically, the detection processing unit 33 detects the supplied current when the acquisition processing unit 32 first acquires the specification data. That is, the detection processing unit 33 detects the supply current when the DIMM 14 is attached to the DIMM socket 13 for the first time.

Further, the detection processing unit 33 detects the supply current when the specification data acquired by the acquisition processing unit 32 does not match the specification data acquired previously. That is, the detection processing unit 33 detects the supply current when the DIMM 14 is replaced.

On the other hand, after the supply current is detected for the DIMM 14 corresponding to the specification data acquired by the acquisition processing unit 32, the detection processing unit 33 detects the supply current until the specification data different from the specification data is acquired. Does not detect current. As a result, it is possible to avoid unnecessary increases in the processing load of the CPU 11 or power consumption in the current detection circuit 19 .

For example, when the operation mode of the DIMM 14 is the second mode, the detection processing unit 33 uses the power supply path switching unit 17 to switch the power supply path from the power supply 16 to the DIMM socket 13 from the first power supply path to the second power supply path. 2 switch to the feed path. As a result, the supply current flows through the resistor 18 provided in the second power supply path. Further, the detection processing unit 33 drives the current detection circuit 19 when the supply current flows through the second power supply path. As a result, it is determined whether or not the voltage corresponding to the supply current across the resistor 18 is higher than the reference voltage, and a control signal indicating the determination result is output from the current detection circuit 19 to the CPU 11 .

Note that the control unit 7 does not have to include the current detection circuit 19 . In this case, the CPU 11 may implement the same function as the current detection circuit 19 by executing the control program. Further, the control unit 7 may detect the current value of the supply current based on the voltage applied across the resistor 18 according to the supply current.

Further, the detection processing unit 33 detects the supply current of the DIMM 14 corresponding to the specification data acquired by the acquisition processing unit 32, and before the specification data different from the specification data is acquired. Supply current may be detected. Alternatively, the detection processing unit 33 may detect the supply current only when the attachment of the DIMM 14 to the DIMM socket 13 is detected for the first time. In this case, the control unit 7 does not have to include the acquisition processing unit 32 .

The power supply control unit 34 predetermines the supply current detected by the detection processing unit 33 when the operation mode of the image forming apparatus 100 is switched from the normal mode to the power saving mode that consumes less power than the normal mode. If the reference value is exceeded, the data stored in the DIMM 14 is saved in the flash memory 15 and the power supply to the DIMM 14 is stopped.

For example, the power supply control unit 34 detects when the control signal output from the current detection circuit 19 is a signal indicating that the voltage corresponding to the supply current applied across the resistor 18 is higher than the reference voltage. It is determined that the supply current detected by the processing unit 33 exceeds the reference value. In this case, the reference voltage is set based on the reference value.

On the other hand, when the operation mode of the image forming apparatus 100 is switched from the normal mode to the power saving mode, if the supply current detected by the detection processing unit 33 does not exceed the reference value, the power supply control unit 34 Power supply to DIMM 14 is not stopped.

Specifically, when the operation mode of the image forming apparatus 100 is switched from the normal mode to the power saving mode, the power supply control unit 34 controls the power supply control unit 34 when the supply current detected by the detection processing unit 33 does not exceed the reference value. switches the operation mode of the DIMM 14 from the first mode to the second mode.

[Identification information acquisition process]
An example of the procedure of identification information acquisition processing executed by the CPU 11 in the image forming apparatus 100 will be described below with reference to FIG. Here, steps S11, S12, .

<Step S11>
First, in step S11, the CPU 11 determines whether or not the acquisition timing has arrived.

Specifically, the CPU 11 determines that the acquisition timing has come when the power of the image forming apparatus 100 is turned on.

Here, when the CPU 11 determines that the acquisition timing has arrived (Yes in S11), the process proceeds to step S12. If the acquisition timing has not arrived (No in S11), the CPU 11 waits for the acquisition timing in step S11.

<Step S12>
In step S12, the CPU 11 acquires the specification data. Here, the processing of step S<b>12 is executed by the acquisition processing unit 32 .

Specifically, the CPU 11 inputs a control signal to the DIMM socket 13 to instruct reading of the specification data. Here, when the DIMM 14 is attached to the DIMM socket 13, the specification data is transmitted from the DIMM 14 to the CPU 11 according to the input control signal. On the other hand, when the DIMM 14 is not attached to the DIMM socket 13 , the specification data is not sent to the CPU 11 .

<Step S13>
In step S13, the CPU 11 determines whether or not the acquisition of the specification data has succeeded.

Specifically, the CPU 11 determines that the specification data has been successfully acquired when the specification data is transmitted before a predetermined time elapses from the execution of the process of step S12. On the other hand, the CPU 11 determines that acquisition of the specification data has failed when the specification data is not transmitted before a predetermined time elapses from the execution of the process of step S12.

Here, when the CPU 11 determines that the acquisition of the specification data has succeeded (Yes side of S13), the process proceeds to step S14. Further, if the acquisition of the specification data has not succeeded (No side of S13), the CPU 11 shifts the process to step S18.

<Step S14>
In step S14, the CPU 11 turns on a mounting flag indicating whether or not the DIMM 14 is mounted in the DIMM socket 13, that is, sets it to "1".

Specifically, in the image forming apparatus 100, the flash memory 15 is provided with a second storage area used for storing the attachment flag. The CPU 11 accesses the second storage area and sets the mounting flag to ON. In the image forming apparatus 100, the mounting flag is set to ON when the DIMM 14 is mounted in the DIMM socket 13, and the mounting flag is set to OFF when the DIMM is not mounted.

<Step S15>
In step S<b>15 , the CPU 11 determines whether or not the specification data acquired in step S<b>12 matches the specification data stored in the first storage area of the flash memory 15 .

Here, when the CPU 11 determines that the specification data acquired in step S12 matches the specification data stored in the first storage area (Yes side of S15), the process proceeds to step S11. If the specification data acquired in step S12 does not match the specification data stored in the first storage area (No in S15), the CPU 11 shifts the process to step S16.

If the specification data is not stored in the first storage area, the CPU 11 determines that the specification data acquired in step S12 does not match the specification data stored in the first storage area. You can

<Step S16>
In step S16, the CPU 11 turns on the non-detection flag indicating whether or not the supply current corresponding to the DIMM 14 attached to the DIMM socket 13 is detected, that is, sets it to "1".

Specifically, in the image forming apparatus 100, the flash memory 15 is provided with a third storage area used for storing the non-detection flag. The CPU 11 accesses the third storage area and sets the non-detection flag to ON. In the image forming apparatus 100, the undetected flag is set to OFF when the supply current corresponding to the DIMM 14 attached to the DIMM socket 13 has been detected, and the undetected flag is set to OFF when the supply current has not been detected. is set to on.

<Step S17>
In step S<b>17 , the CPU 11 stores the specification data acquired in step S<b>12 in the first storage area of the flash memory 15 .

<Step S18>
In step S18, the CPU 11 turns off the mounting flag, that is, sets it to "0".

[Power supply control process]
Hereinafter, the power supply control method of the present invention will be described together with an example of the power supply control process executed by the CPU 11 in the image forming apparatus 100 with reference to FIG. The power supply control process is executed when the operation mode of the image forming apparatus 100 is switched from the normal mode to the power saving mode.

<Step S21>
First, in step S<b>21 , the CPU 11 determines whether or not the DIMM 14 is attached to the DIMM socket 13 .

Specifically, the CPU 11 determines that the DIMM 14 is attached to the DIMM socket 13 when the attachment flag is set to ON.

Here, when the CPU 11 determines that the DIMM 14 is attached to the DIMM socket 13 (Yes side of S21), the process proceeds to step S22. If the DIMM 14 is not installed (No side of S21), the CPU 11 ends the power supply control process.

<Step S22>
In step S22, the CPU 11 determines whether or not the supply current corresponding to the DIMM 14 attached to the DIMM socket 13 has been detected.

Specifically, when the undetected flag is set to OFF, the CPU 11 determines that the supply current corresponding to the DIMM 14 attached to the DIMM socket 13 has been detected.

Here, when the CPU 11 determines that the supply current corresponding to the DIMM 14 attached to the DIMM socket 13 has been detected (Yes side of S22), the process proceeds to step S24. If the supply current has not been detected (No side of S22), the CPU 11 shifts the process to step S23.

<Step S23>
In step S23, the CPU 11 executes current detection processing described below.

[Current detection processing]
Here, the current detection process executed in step S23 of the power supply control process will be described with reference to FIG.

<Step S41>
First, in step S41, the CPU 11 switches the operation mode of the DIMM 14 from the first mode to the second mode.

Specifically, the CPU 11 inputs to the DIMM 14 a control signal instructing switching of the operation mode.

The CPU 11 also switches the operation mode of the DRAM 12 as well as the DIMM 14 from the first mode to the second mode.

<Step S42>
At step S42, the CPU 11 detects the supply current. Here, the processing of step S42 is an example of the detection step of the present invention, and is executed by the detection processing section 33. FIG.

Specifically, the CPU 11 uses the power supply path switching unit 17 to switch the power supply path from the power supply 16 to the DIMM socket 13 from the first power supply path to the second power supply path. The CPU 11 also drives the current detection circuit 19 . As a result, it is determined whether or not the voltage corresponding to the supply current across the resistor 18 is higher than the reference voltage, and a control signal indicating the determination result is output from the current detection circuit 19 to the CPU 11 .

After detecting the supply current, the CPU 11 uses the power supply path switching unit 17 to switch the power supply path from the power supply 16 to the DIMM socket 13 from the second power supply path to the first power supply path. It is only when the supply current is detected that the second power supply path is turned on instead of the first power supply path.

<Step S43>
In step S43, the CPU 11 determines whether or not the supply current detected in step S42 is equal to or less than the reference value.

Specifically, when the control signal output from the current detection circuit 19 is a signal indicating that the voltage corresponding to the supply current applied across the resistor 18 is equal to or lower than the reference voltage, the CPU 11 performs step S42. determines that the supply current detected by is equal to or less than the reference value.

Here, when the CPU 11 determines that the supply current detected in step S42 is equal to or less than the reference value (Yes side of S43), the process proceeds to step S44. If the supplied current is not equal to or less than the reference value (No side of S43), the CPU 11 shifts the process to step S45.

<Step S44>
In step S44, the CPU 11 turns on a power supply permission flag indicating whether power supply to the DIMM 14 is permitted in the power saving mode, that is, sets it to "1".

Specifically, in the image forming apparatus 100, the flash memory 15 is provided with a fourth storage area used for storing the power supply permission flag. The CPU 11 accesses the fourth storage area and sets the power supply permission flag to ON. In the image forming apparatus 100, the power supply permission flag is set to ON when power supply to the DIMM 14 in the power saving mode is permitted, and the power supply permission flag is set to OFF when power supply is not permitted.

<Step S45>
In step S45, the CPU 11 turns off the power supply permission flag, that is, sets it to "0".

<Step S46>
In step S46, the CPU 11 turns off the non-detection flag, that is, sets it to "0".

<Step S47>
In step S47, the CPU 11 determines whether or not the operation mode of the image forming apparatus 100 has returned from the power saving mode to the normal mode.

Here, when the CPU 11 determines that the operation mode of the image forming apparatus 100 has returned from the power saving mode to the normal mode (Yes side of S47), the process proceeds to step S48. If the operation mode of image forming apparatus 100 has not returned from the power saving mode (No side of S47), CPU 11 prevents the operation mode of image forming apparatus 100 from returning from the power saving mode in step S47. await.

<Step S48>
In step S48, the CPU 11 switches the operation mode of the DIMM 14 from the second mode to the first mode.

The CPU 11 also switches the operation mode of the DRAM 12 as well as the DIMM 14 from the second mode to the first mode.

With this, the explanation of the current detection process is finished, and the explanation of the processes after step S24 of the power supply control process is restarted.

<Step S24>
In step S24, the CPU 11 determines whether or not the supply current detected by the current detection process is equal to or less than the reference value.

Specifically, when the power supply permission flag is set to ON, the CPU 11 determines that the supply current detected by the current detection process is equal to or less than the reference value.

Here, when the CPU 11 determines that the supply current detected by the current detection process is equal to or less than the reference value (Yes side of S24), the process proceeds to step S25. If the supplied current is not equal to or less than the reference value (No side of S24), the CPU 11 shifts the process to step S28.

<Step S25>
In step S25, the CPU 11 switches the operation mode of the DIMM 14 from the first mode to the second mode. Here, the processing of step S25 is an example of the power supply control step of the present invention, and is executed by the power supply control unit 34 .

The CPU 11 also switches the operation mode of the DRAM 12 as well as the DIMM 14 from the first mode to the second mode.

<Step S26>
In step S26, the CPU 11 determines whether or not the operation mode of the image forming apparatus 100 has returned from the power saving mode to the normal mode.

Here, when the CPU 11 determines that the operation mode of the image forming apparatus 100 has returned from the power saving mode to the normal mode (Yes in S26), the process proceeds to step S27. If the operation mode of image forming apparatus 100 has not returned from the power saving mode (No side of S26), CPU 11 prevents the operation mode of image forming apparatus 100 from returning from the power saving mode in step S26. await.

<Step S27>
In step S27, the CPU 11 switches the operation mode of the DIMM 14 from the second mode to the first mode.

The CPU 11 also switches the operation mode of the DRAM 12 as well as the DIMM 14 from the second mode to the first mode.

<Step S28>
In step S28, the CPU 11 saves the data stored in the DIMM 14 to the flash memory 15 and stops supplying power to the DIMM 14. FIG. Here, the process of step S28 is an example of the power supply control step of the present invention, and is executed by the power supply control unit 34. FIG.

Specifically, when stopping the power supply to the DIMM 14 , the CPU 11 uses the power supply path switching unit 17 to cut off both the first power supply path and the second power supply path.

The CPU 11 stops supplying power to the DIMM 14 while switching the operation mode of the DRAM 12 from the first mode to the second mode.

<Step S29>
In step S29, the CPU 11 determines whether or not the operation mode of the image forming apparatus 100 has returned from the power saving mode to the normal mode.

Here, when the CPU 11 determines that the operation mode of the image forming apparatus 100 has returned from the power saving mode to the normal mode (Yes in S29), the process proceeds to step S30. If the operation mode of image forming apparatus 100 has not returned from the power saving mode (No side of S29), CPU 11 prevents the operation mode of image forming apparatus 100 from returning from the power saving mode in step S29. await.

<Step S30>
In step S<b>30 , the CPU 11 resumes power supply to the DIMM 14 and stores the data saved in the flash memory 15 in the DIMM 14 .

Specifically, when restarting the power supply to the DIMM 14 , the CPU 11 uses the power supply path switching unit 17 to turn on the first power supply path.

The CPU 11 resumes supplying power to the DIMM 14 while switching the operation mode of the DRAM 12 from the second mode to the first mode.

As described above, in the image forming apparatus 100, when the operation mode is switched from the normal mode to the power saving mode, if the supply current detected in advance exceeds the reference value, the data stored in the DIMM 14 is transferred to the flash memory. 15, the power supply to the DIMM 14 is stopped, and the power supply to the DIMM 14 is not stopped if the current supplied does not exceed the reference value. Accordingly, it is possible to switch whether or not to supply power to the DIMM 14 in the power saving mode according to the power consumption of the DIMM 14 attached to the DIMM socket 13 . Therefore, it is possible to suppress the power consumption in the power saving mode to a certain level or less and suppress the lengthening of the recovery time from the power saving mode.

Note that the DIMM 14 may not be capable of switching the operation mode to the second mode. In this case, the supply current is the current supplied to the DIMMs 14 operating in the first mode.

Also, the control unit 7 may not include the DRAM 12 . In this case, the DIMMs 14 may be attached to the DIMM sockets 13 when the image forming apparatus 100 is manufactured.

In addition, when the operation mode of the image forming apparatus 100 is switched from the normal mode to the power saving mode, the power supply control unit 34 supplies power to the DRAM 12 when the supply current detected by the detection processing unit 33 exceeds the reference value. The stored data may be saved in the flash memory 15, the power supply to the DRAM 12 may be stopped, and the power supply to the DRAM 12 may not be stopped if the supply current does not exceed the reference value. In this case, DRAM 12 is the specific memory of the present invention.

Further, when the operation mode of the image forming apparatus 100 is switched from the normal mode to the power saving mode, the power supply control unit 34 controls the DRAM 12 and Data stored in both DIMMs 14 are saved in flash memory 15, power supply to both DRAM 12 and DIMM 14 is stopped, and power supply to both DRAM 12 and DIMM 14 is stopped when the supply current does not exceed the reference value. It may not be. In this case, both DRAM 12 and DIMM 14 are specific memories of the present invention.

Further, when the supply current detected by the detection processing unit 33 exceeds the reference value, the power supply control unit 34 controls the power supply based on the comparison result between the supply current and the current supplied from the power supply 16 to the DRAM 12. You may switch the stop target. For example, when the supply current detected by the detection processing unit 33 is less than the current supplied from the power supply 16 to the DRAM 12, the power supply control unit 34 sets the power supply stop target to the DRAM 12, and the supply current is If the current is greater than or equal to the current supplied from the power supply 16 to the DRAM 12 , the DIMM 14 may be set as the power supply stop target. Further, the power supply control unit 34 may switch the power supply stop target based on the data transfer rate of the DIMM 14 when the supply current detected by the detection processing unit 33 exceeds the reference value. Further, when the supply current detected by the detection processing unit 33 exceeds the reference value, the power supply control unit 34 may switch the power supply stop target based on information included in the specification data.

1 ADF
2 image reading unit 3 image forming unit 4 sheet conveying unit 5 operation display unit 6 power supply unit 7 control unit 11 CPU
12 DRAM
13 DIMM socket 14 DIMM
15 flash memory 16 power supply 17 power supply path switching unit 18 resistor 19 current detection circuit 20 control board 31 switching processing unit 32 acquisition processing unit 33 detection processing unit 34 power supply control unit 100 image forming apparatus

Claims (7)

a mounting part to which a volatile first memory is mounted;
a non-volatile second memory;
a detection processing unit that detects a supply current supplied to the first memory attached to the attachment unit;
When the operation mode of the device is switched from the normal mode to the power saving mode in which power consumption is lower than that of the normal mode, if the supply current detected by the detection processing unit exceeds a predetermined reference value, the first saving data stored in one memory to the second memory, stopping power supply to the first memory, and not stopping power supply to the first memory when the supply current does not exceed the reference value. a control unit;
Information processing device. The first memory is capable of switching an operation mode between a first mode and a second mode that consumes less power than the first mode,
the supply current is a current supplied to the first memory operating in the second mode,
The power supply control unit switches the operation mode of the first memory from the first mode to the second mode when the supply current detected by the detection processing unit does not exceed the reference value.
The information processing device according to claim 1 . an acquisition processing unit that acquires the identification information of the first memory from the first memory attached to the attachment unit each time a predetermined acquisition timing arrives;
The detection processing unit detects the supply current when the identification information acquired by the acquisition processing unit does not match the previously acquired identification information.
The information processing apparatus according to claim 1 or 2. After the supply current is detected for the first memory corresponding to the identification information acquired by the acquisition processing unit, the detection processing unit performs the detection until the identification information different from the identification information is acquired. not detect the supply current,
The information processing apparatus according to claim 3. comprising the first memory separate from the first memory attached to the attachment part;
The power supply control unit saves data stored in a specific memory among the plurality of first memories to the second memory when the supply current detected by the detection processing unit exceeds the reference value. stopping power supply to the specific memory, and not stopping power supply to the specific memory when the supplied current does not exceed the reference value;
The information processing apparatus according to any one of claims 1 to 4. One or both of an image reading unit that reads an image of a document and an image forming unit that forms an image based on image data,
The information processing apparatus according to any one of claims 1 to 5. A power supply control method executed by an information processing device including a mounting unit to which a volatile first memory is mounted and a nonvolatile second memory,
a detection step of detecting a supply current supplied to the first memory attached to the attachment portion;
When the operation mode of the information processing device is switched from the normal mode to the power saving mode that consumes less power than the normal mode, if the supply current detected by the detection step exceeds a predetermined reference value, the Saving data stored in the first memory to the second memory, stopping power supply to the first memory, and not stopping power supply to the first memory when the supply current does not exceed the reference value a power supply control step;
A power supply control method including.

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