JP5336946B2 - Information processing device - Google Patents

Description

  The present invention relates to an information processing apparatus that includes a DC (Direct Current) power supply device such as a battery and operates by switching between driving by an AC (Alternating Current) power supply and driving by a DC power supply device.

  2. Description of the Related Art Conventionally, a computer that is assumed to be portable, such as a notebook personal computer, can be operated not only by an AC power source but also by a battery. In general, in such a computer, in order to extend the operable time by the battery, the computer operates in the power saving mode in which the power is operated as compared with the operation by the AC power source.

  In such a computer, a technique of automatically shifting to a power saving mode without requiring any user operation when the supply of the AC power supply is stopped during the operation by the AC power supply is used (for example, the following patent document). 1).

JP-A-5-233551

  On the other hand, there are computers that incorporate a battery in a casing in consideration of convenience during carrying. In addition, it is desirable that a small battery can be used for carrying even if it is not built in the housing. In particular, when not only the battery but also an AC power supply device such as an AC adapter or an AC module is built in the casing, the convenience of carrying is improved. For this purpose, it is particularly desirable to reduce the size of the battery. In such a case, if a battery having a rated power smaller than the maximum power consumption of the computer can be used, the battery can be reduced in size and the degree of freedom in designing the computer is increased.

  In the above-described conventional computer, when the supply stop of the AC power supply is detected, the processing until shifting to the power saving mode is performed by software. Specifically, for example, an EC (Embedded Controller) detects an AC power supply stop and notifies the OS (Operating System) of the detection result. When the OS receives the notification, the OS instructs to decrease the operating frequency of the CPU, decrease the brightness of the LCD, etc. in accordance with the operation in the predefined power saving mode. In order to carry out this series of operations, it takes a time of 100 milliseconds.

  In general, a computer is often configured not to be driven by a battery for a period of several tens of milliseconds after the supply of AC power is stopped so as to cope with an instantaneous power failure. According to the method for shifting to the power mode, since it takes a time of 100 milliseconds, it may be necessary to drive the battery before the AC power supply is stopped and the mode is shifted to the power saving mode. In a conventional computer, it is assumed that the maximum power consumption is smaller than the rated power of the battery, so that there is no problem even if the battery is driven before shifting to the power saving mode. However, when using a battery with a rated power smaller than the maximum power consumption of the computer, depending on the state of the load, it operates in the AC power drive mode (not in the power saving mode) even after switching to battery operation. There has been a problem that the power consumption of the computer at the time of switching to battery operation may exceed the rated power of the battery.

  The present invention has been made in view of the above, and provides an information processing apparatus and a power saving control method capable of quickly reducing power consumption before starting driving with a DC power supply after the supply of AC power is stopped. The purpose is to obtain.

  In order to solve the above-described problems and achieve the object, an information processing apparatus according to the present invention includes a calculation unit, and operates with an external AC power supply and with a DC power supply supplied by a DC power supply built therein. An information processing apparatus that can operate by switching between an operation and an AC power supply determination unit that determines whether or not AC power is supplied, and when the AC power supply determination unit determines that AC power is not supplied And power saving start control means for controlling the arithmetic means to shift to a power saving state before the drive power supply is switched to the DC power supply.

  The information processing apparatus according to the next invention is characterized in that the arithmetic means is a CPU and the power saving state is a CPU throttling state.

  The information processing apparatus according to the next invention further includes a storage unit for storing data, and the power saving start control unit determines that the AC power supply determination unit has no AC power supply. In addition, the storage means is controlled to shift to a power saving state.

  The information processing apparatus according to the next invention further includes a display device for displaying information, and the power saving start control means determines that the AC power supply determination means has no AC power supply. In addition, the display device is further controlled to shift to a power saving state.

  An information processing apparatus according to a next invention is characterized in that the display device is an LCD, and the power saving state of the display device is an LCD backlight OFF state or an LCD backlight brightness reduction state. To do.

  The information processing apparatus according to the next invention further includes an external storage device for storing data, and the power saving start control means determines that the AC power supply determination means does not supply AC power. In this case, the external storage device is further controlled to shift to a power saving state.

  The information processing apparatus according to the next invention further comprises input / output means for performing input / output to the arithmetic means, and input / output control means for controlling input / output with respect to the input / output means. When the AC power supply determining means determines that the AC power supply is not supplied, the start control means further instructs the input / output control means to shift to a power saving state. The input / output means is controlled to shift to a power saving state based on an instruction from the power saving start control means.

  The information processing apparatus according to the next invention is characterized in that the input / output means is storage means for storing data.

  The information processing apparatus according to the next invention is characterized in that the input / output means is a display device for displaying information.

  An information processing apparatus according to a next invention is characterized in that the display device is an LCD, and the input / output control means is put into a power saving state by thinning a processing rate of an image to be displayed on the display device. .

  The information processing apparatus according to the next invention is characterized in that the input / output means is an external storage device for storing data.

  The information processing apparatus according to the next invention acquires temperature and current as battery information from the DC power supply apparatus, and when the battery information becomes less than a predetermined threshold value, the power supply that cancels the power saving state And a control means.

  In the information processing apparatus according to the next invention, the power supply control unit calculates a consumption current based on the battery information from the DC power supply apparatus, and determines whether or not the consumption current is less than a predetermined DC power supply rated current. When the current consumption is determined not to be less than the DC power supply rated current, the released power saving state is restored.

  The information processing apparatus according to the next invention is characterized in that the maximum power consumption of the apparatus exceeds the rated power of the DC power supply apparatus.

  The information processing apparatus according to the next invention further includes an AC power supply apparatus that supplies power input from the AC power supply to the apparatus, and the DC power supply apparatus and the AC power supply apparatus are built in the same casing. It is characterized by.

  The power saving control method according to the next invention includes an arithmetic means, and is an information processing apparatus that can operate by switching between an operation using an external AC power supply and an operation using a DC power supply supplied by a DC power supply built therein. The AC power supply determining step for determining whether or not AC power is supplied, and when the AC power supply is determined not to be supplied, the calculation means is configured to switch the drive power before switching to the DC power. A power saving start control step for controlling to shift to the power saving state.

  In the information processing apparatus according to the present invention, the charger unit monitors whether or not the AC power is supplied. When the AC power is not supplied, the charger unit notifies the power saving start control unit, and the power saving start control unit notifies the notification. Since the CPU is controlled to perform throttling on the basis of this, the power consumption can be quickly reduced after the supply of AC power is stopped.

FIG. 1 is a diagram showing a configuration example of a portable computer according to the present invention. FIG. 2 is a diagram showing an example of a power supply method for a portable computer according to the present invention. FIG. 3 is a flowchart illustrating an example of the power saving control method. FIG. 4 is a diagram illustrating an example of the power saving mode transition condition and the power saving mode release condition. FIG. 5 is a flowchart showing an example of the operation of the EC.

  Embodiments of an information processing apparatus and a power saving control method according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

  FIG. 1 is a diagram showing a configuration example of a portable computer according to the present invention. In the present embodiment, a portable computer will be described as an example of the information processing apparatus according to the present invention. As shown in FIG. 1, the portable computer of this embodiment includes a DC power supply device 1, an AC power supply device 2, an EC 3, a charger circuit 4, an arithmetic device 5, a power saving start control circuit 6, and a display device. 7, an internal I / O (input / output) device 8, a switching device 9, a storage device (memory) 13, and an external I / O (input / output) device 14. The power supply line 10 is a power supply line between the DC power supply device 1 and the switching device 9, and the power supply line 11 is a power supply line between the AC power supply device 2 and the switching device 9. The EC 3, charger circuit 4, arithmetic device 5, power saving start control circuit 6, internal input / output device 8, and storage device 13 are mounted on the substrate 15. The portable computer according to the present embodiment includes components included in a normal computer in addition to the components illustrated in FIG. 1. Here, components necessary for explaining the operation of the present invention are shown. Yes.

  The DC power supply device 1 is a battery pack that supplies DC power. The AC power supply device 2 is an AC adapter, an AC module, or the like that takes in AC power from an external outlet or the like via an AC cable 12 and supplies it by rectification.

  The EC3 is a control device (power supply control means) that also controls the power supply system, acquires battery information such as temperature and current from the DC power supply device 1, and saves power by which the transition is determined by the EC3 based on the battery information. Control of transition to the EC power saving mode, which is a mode, and return from the EC power saving mode are controlled.

  The charger circuit 4 is a circuit that is provided between the AC power supply device and the present device, receives the supply from the AC power supply line, charges the DC power supply device 1, and has a function of determining the supply state of the AC power supply. Further, the charger circuit 4 monitors whether the AC power is supplied by monitoring the power supply line 11 between the AC power supply device 2 and the switching device 9. In this embodiment, the charger circuit 4 has a function of an AC power supply determination unit that monitors the supply of AC power and determines whether or not the AC power is supplied. A power supply determination unit may be provided, and the AC power supply determination unit may operate the charger circuit 4 described below.

  The arithmetic device 5 is constituted by a CPU (Central Processing Unit) 5-1, and is arithmetic means for performing numerical calculation, information processing, device control, and the like. The power saving start control circuit 6 is a circuit that implements logic by hardware such as a PLD (Programmable Logic Device), and transmits a CPU throttling start signal to the CPU 5-1 based on an instruction from the charger circuit 4. To do.

  The display device 7 is a device that performs screen display. The display device 7 includes an LCD (Liquid Crystal Display) backlight control circuit 7-1, and the LCD backlight control circuit 7-1 controls the backlight of the liquid crystal screen. The internal I / O device 8 is composed of, for example, a chip set 8-1, and controls input / output of a memory interface and others (image processing interface, network interface, etc.). The switching device 9 selects a power supply line that is an input from either the DC power supply device 1 or the AC power supply device 2 based on an instruction from the charger circuit 4, and the CPU 5-1 in the portable computer or the like from the selected power supply line. The connection destination is switched so that the power supply is connected to the board on which the is mounted.

  The storage device 13 is a memory for storing data used by the CPU 5-1 for calculation. The external I / O device 14 includes, for example, an HDD (Hard Disk Drive) 14-1 and a CDD (Compact Disk Drive) 14-2. The external I / O device 14 is a device that functions as a so-called external storage device. Here, the external I / O device 14 is mounted on a board different from the board on which the CPU 5-1 is mounted, but is mounted on the same board as the CPU 5-1. Alternatively, it may be connected to the substrate via a cable without being mounted on the substrate. Although FIG. 1 shows an example in which the HDD 14-1 and the CDD 14-2 are provided as the external I / O device 14, the present invention is not limited to this, and a DVD drive, an SSD (Solid State Drive), or the like is provided. Also good. That is, the external I / O device 14 may include one or more of the HDD 14-1, the CDD 14-2, a DVD drive other than these, a solid state drive (SSD), and the like.

  FIG. 2 is a diagram illustrating an example of a power supply method for the portable computer according to the present embodiment. As shown in FIG. 2, power is supplied to the substrate 15 from the DC power supply device 1 or the AC power supply device 2 via the switching device 9, and power is supplied to each component on the substrate 15. In addition, power is supplied to the display device 7 and the external I / O device 14 via the substrate 15. FIG. 2 is an example of a power supply method, and the power supply method and supply path for each component are not limited to this, and any supply method and supply path may be used. For example, power may be supplied to the display device 7 and the external I / O device 14 via the switching device 9 by a separate cable without going through the substrate 15.

  The portable computer of this embodiment has an AC power mode in which operation is performed by an AC power source and a DC power mode in which operation is performed by a DC power source. In addition, the portable computer of this embodiment consumes power due to a decrease in the operating frequency of the CPU 5-1 (CPU throttling), a decrease in brightness of the LCD backlight, a decrease in memory access speed (memory throttling), and the like. Has reduced power saving mode. When operating in either the AC power mode or the DC power mode, if the predetermined condition is satisfied, the mode is shifted to the power saving mode. In addition, here, when the AC power mode is shifted to the DC power mode, the mode is automatically shifted to the power saving mode regardless of other conditions. Further, when the supply of AC power resumes during the operation in the DC power mode, the mode shifts to the AC power mode.

  The operation of this embodiment will be described. FIG. 3 is a flowchart illustrating an example of the power saving control method according to this embodiment. As shown in FIG. 3, the charger circuit 4 first monitors the power supply line 11 and determines whether or not AC power is supplied (step S11). At this time, whether or not AC power is supplied is determined, for example, when a predetermined voltage threshold is set for the voltage and the voltage of the power supply line 11 is equal to or higher than the voltage threshold. It is determined that there is power supply, and it is determined that there is no AC power supply when it is less than the voltage threshold. If this voltage threshold value is set high, AC power supply stoppage can be detected quickly, but if it is set too high, there is a possibility of false detection. Set.

  If it is determined in step S11 that AC power is not supplied (step S11 AC power is not supplied), the charger circuit 4 invalidates the AC power supply detection signal (step S12). The AC power supply detection signal is a signal indicating whether or not AC power supply is detected. When the AC power supply detection signal is invalid, it indicates that there is no AC power supply. When the AC power supply detection signal is valid, it indicates that there is AC power supply. The value of the AC power supply detection signal is notified to the power saving start control circuit 6 and EC3 when the charger circuit 4 changes the value of the AC power supply detection signal, for example.

  When notified that the AC power supply detection signal is invalid, the power saving start control circuit 6 validates the CPU throttling start signal and notifies the CPU 5-1 of the signal (step S13). The CPU 5-1 starts the throttling operation based on the CPU throttling start signal. The CPU throttling start signal is a signal indicating whether or not to perform CPU throttling, and indicates that the CPU throttling is performed when the CPU is throttling and the CPU throttling is canceled when the throttling is invalid.

  Here, in step S13, the CPU throttling is controlled to perform CPU throttling, but the power saving start control circuit 6 consumes the display device 7 in step S13. You may make it instruct | indicate the operation | movement which reduces electric power. As an operation for reducing the power consumption of the display device 7, for example, the LCD backlight control circuit 7-1 is instructed to turn off the LCD backlight or lower the luminance.

  In step S13, the power saving start control circuit 6 instructs the storage device 13 to perform memory throttling in addition to the CPU throttling, or the external I / O device 14 performs throttling (input / output speed). May be instructed. When there are two or more devices (for example, HDD 14-1, CDD 14-2, etc.) constituting the external I / O device 14, the throttling may be instructed to all of them. Some devices may be instructed to throttle.

  In step S13, in addition to the CPU throttling, the power saving start control circuit 6 restricts the throttling (the input / output operation speed and the like controlled by the chipset 8-1) to the chipset 8-1. (Processing for reducing power consumption) may be instructed. In addition, an instruction for reducing the power consumption may be given to two or more of the display device 7, the storage device 13, the input / output means of the external I / O device 14, and the chip set 8-1. Good.

  Further, instead of the power saving start control circuit 6 directly instructing the storage device 13, the display device 7, and the external I / O device 14, the chip set 8-1 is instructed to perform throttling, and the chip set 8 -1 controls the input / output of one or more of the input / output means of the storage device 13, the display device 7, and the external I / O device 14, whereby the storage device 13, the display device 7, the external I / O device Any one or more of the 14 input / output means may reduce power consumption. That is, the input / output speed of the input / output means (the storage device 13, the display device 7, the external I / O device 14, etc.) that is the input / output control target device of the chip set 8-1 as the input / output control means By controlling the access method and the like, power consumption is reduced. Specifically, for example, when receiving an instruction for throttling, the chip set 8-1 thins out (throttling) an image processing rate to be displayed on the display device 7.

  When the display device 7 is an LCD, as an operation for reducing power consumption, the power saving start control circuit 6 turns off the LCD backlight or lowers the luminance with respect to the LCD backlight control circuit 7-1. There is a case where the chip set 8-1 which is an input / output control means thins out (throttling) an image processing rate to be displayed on the display device 7 when receiving a throttling instruction. , Each may be performed independently or simultaneously.

  Here, the CPU throttling is performed as an example for power saving of the CPU. However, the present invention is not limited to this, and if the CPU can be power saved by another method, the method is used. You may make it notify to CPU5-1 at step S13 so that CPU may save power. In this embodiment, an LCD is provided as a display device, and the backlight of the LCD is turned off or the brightness is reduced. However, when a display device other than the LCD is provided, the brightness of the display device is reduced. For example, the display device may save power.

  The charger circuit 4 instructs the switching device 9 to switch the power supply line supplied to the substrate 15 from the power supply line 11 from the AC power supply device 2 to the power supply line 10 from the DC power supply device 1 (step S14). Based on the instruction, the switching device 9 switches the connection so that the power supply line 10 from the DC power supply device 1 becomes a power supply line to the substrate.

  In response to the invalidation of the AC power supply detection signal, the EC 3 controls to shift to the operation mode (power saving mode) in the DC power supply device 1 and validates the EC power saving control signal (step S15). ). The EC power saving control signal is a signal indicating whether or not EC3 is in the power saving mode, and indicates that it is in the power saving mode when it is valid, and indicates that it is not in the power saving mode when it is invalid. Note that the power saving mode state (EC3 is a power saving mode controlled by an EC power saving control signal) and the low power state (hereinafter referred to as a provisional power saving mode) designated by the power saving start control circuit 6 in step S13. ) May be in the same state or different states. For example, in the power saving mode, CPU throttling and lowering the brightness of the LCD backlight may be performed, and in the provisional power saving mode, CPU throttling and turning off the LCD backlight may be performed.

  The EC 3 acquires battery information (current, temperature, etc.) from the DC power supply device 1 (step S16), and compares the acquired battery information with a power saving mode cancellation condition stored in advance, thereby satisfying the power saving mode cancellation condition. Whether or not (step S17). If it is determined that the power saving mode cancellation condition is satisfied (Yes in step S17), the EC power saving control signal is invalidated and control is performed to return from the power saving mode (step S18). Further, the EC power saving control signal is notified to the power saving start control circuit 6.

  FIG. 4 is a diagram illustrating an example of the power saving mode transition condition and the power saving mode release condition. The upper current value and temperature value in FIG. 4 indicate threshold values (power saving mode transition conditions) when shifting to the power saving mode, and the lower current value and temperature value are those when canceling the power saving mode. Indicates a threshold value (power saving mode release condition). In step S17 described above, the determination is made using the lower power saving mode release condition. At this time, when both the current and the temperature are lower than the value indicated as the power saving mode release condition, the power saving mode is released. It is determined that the release condition is satisfied. The power saving mode transition condition is not used in the operation described in the present embodiment. However, even when the power saving mode is cancelled, the EC 3 periodically acquires battery information, for example, and the battery information is in the power saving mode. When the transition condition is satisfied (power saving mode transition condition), the mode is shifted to the power saving mode.

  In response to the invalidation of the EC power saving control signal, the power saving start control circuit 6 invalidates the CPU throttling start signal and notifies the CPU 5-1 of the signal (step S19). The CPU 5-1 ends the CPU throttling operation based on the notification. At this time, if another power saving operation such as turning off the LCD backlight, lowering the brightness, memory throttling, or chipset throttling is performed as a provisional power saving mode in step S13, CPU throttling Not only the cancellation but also the power saving operation in another provisional power saving mode may be canceled.

  On the other hand, if it is determined in step S17 that the power saving mode cancellation condition is not satisfied (No in step S17), the charger circuit 4 determines whether or not the AC power has been restored by determining whether or not the AC power is supplied. It is determined whether or not (step S20). If it is determined that the AC power supply has been restored (Yes at Step S20), processing for shifting to the AC power supply operation mode is performed (Step S21), and the process returns to Step S11.

  Specifically, as processing for shifting to the AC power supply operation mode, the charger circuit 4 invalidates the AC power supply signal and notifies the EC3 of the signal, and the EC3 receives the notification and receives the AC power supply. Control to shift to the operation mode. Further, the power saving start control circuit 6 invalidates the CPU throttling start signal, notifies the CPU 5-1 of the signal, and the CPU 5-1 ends the throttling operation based on the signal. If it is determined in step S20 that the AC power has not been restored (No in step S20), the process returns to step S16.

  FIG. 5 is a flowchart showing an example of the operation of the EC 3 of this embodiment. As described in the flowchart of FIG. 3, the EC 3 determines whether the AC power supply detection signal is valid based on the AC power supply detection signal notified from the charger circuit 4 (step S31). If it is determined that the AC power supply detection signal is invalid (No in step S31), the EC power saving control signal is validated, and control is performed to shift to the power saving mode of the DC power supply operation mode (step S32). Battery information is acquired from the device 1 (step S33).

  And EC3 judges whether the cancellation | release conditions of power saving mode are satisfy | filled as demonstrated in said step S17 based on the battery information acquired from the DC power supply device 1 (step S34). If it is determined that the condition for canceling the power saving mode is not satisfied (No in step S34), the EC power saving control signal remains valid, the power saving mode is continued (step S35), and the process returns to step S31.

  On the other hand, when it is determined in step S31 that the AC power supply detection signal is valid (Yes in step S31), control is performed to shift to the AC power supply operation mode (step S36). The shift is performed by controlling the power saving mode by setting the EC power saving control signal to be valid or invalid by normal power management in the AC power supply operation mode (step S37), and the process returns to step S31.

  If it is determined in step S34 that the power saving mode release condition is satisfied (Yes in step S34), the EC power saving control signal is invalidated and control is made to return from the power saving mode (step S38), and step S31. Return to.

  In the above example, when the AC power mode is switched to the DC power mode, the mode is automatically shifted to the power saving mode (step S15, step S32). In S32, the mode is shifted to the DC power supply mode, and in step S17 (step S34), it is determined whether or not the power saving mode setting condition is satisfied based on the battery information, and when the condition is satisfied, the mode is shifted to the power saving mode. May be. In this case, in step S17 (step S34) for the second and subsequent times when the mode is shifted to the DC power supply mode, it is determined whether or not the condition for canceling the power saving mode is satisfied, as in the above example. If the power saving mode setting condition is not satisfied, the mode does not shift to the power saving mode, but the operations such as CPU throttling performed in step S13 are performed. Therefore, when it is determined in step S17 (step S34) after the second time that the power saving mode release condition is satisfied, the EC 3 instructs the power saving start control circuit 6 to stop the operation such as CPU throttling. Like that.

  The time required from the time when the charger circuit 4 determines that no AC power is supplied to the time when the power line 10 from the DC power supply 1 is supplied to the board depends on the ability of the computer, but is a very long time. Not (for example, less than 1 millisecond). On the other hand, in the conventional technology, for example, after the charger circuit 4 determines that the AC power is not supplied, the EC 3 notifies the OS and the EC 3 notifies the OS, and the OS shifts to the power saving mode. carry out. As described above, since processing by the EC3 and OS software is performed, the time required from the determination that no AC power is supplied to the transition to the power saving mode is in units of 100 milliseconds. In this case, even if the operation by the DC power supply device 1 is started, there is a possibility that a state in which the operation is not shifted to the power saving mode may occur.

  For example, when the rated power of the DC power supply device 1 is smaller than the maximum power consumption of the information processing device for miniaturization, during this time (even if the operation of the DC power supply device 1 starts, the mode shifts to the power saving mode. (If not), there is a possibility that the rated power of the DC power supply 1 is not satisfied.

On the other hand, for example, in the case where the AC power supply 2 can withstand a momentary power interruption (about 100 milliseconds) of the AC power supply, within a predetermined time (about 100 milliseconds) after the supply of AC power is stopped. For example, the operation by the DC power supply device 1 may not be started. Therefore, there is no problem as long as the mode is shifted to the power saving mode so that the power supply is within the rated power of the DC power supply 1 within a predetermined time after the supply of AC power is stopped.

  In the present embodiment, when the power saving start control circuit 6 that performs processing by hardware receives a notification from the charger circuit 4, the charger circuit 4 controls the operation such as CPU throttling directly. After determining that there is no power supply, it is possible to instruct CPU throttling in the order of microseconds. Therefore, power consumption can be reduced before the operation by the DC power supply device 1 is started, and a state where the rated power of the DC power supply device 1 is not satisfied can be avoided.

  In addition, when the rated power of the DC power supply device 1 is smaller than the maximum power consumption (for a portable computer), the EC 3 periodically acquires the current consumption even during operation by the DC power supply device 1 (for example, The battery information current is periodically acquired), and it is monitored whether or not the power consumption exceeds the rated current of the DC power supply device 1. In step S19, after canceling the CPU strtroling and the like, the current consumption is a predetermined value from the rated current of the DC power supply device 1 (a margin for shifting to the power saving mode before exceeding the rated current, a value of 0 or more). When it is determined that the current threshold value obtained by subtracting is exceeded, control is performed so as to shift to the temporary power saving mode again.

  On the portable computer according to the present embodiment, various management programs such as an operating system (OS) and a database management program as well as various application programs for performing business processing are operating (specifically, each program is stored in the storage device 13). And is executed by the CPU 5-1).

  Here, it is assumed that the current consumption (power consumption) of a portable computer varies greatly. For example, when a plurality of application programs operate in parallel, an application program that requires complicated arithmetic processing operates. Or when a large amount of data is transferred between the storage device 13 and the external I / O device 14 due to a large amount of database access.

  In such a case, fluctuations in current consumption (load fluctuations) of the substrate 15 and the external I / O device 14 become large, and in comparison with the normal operation in relation to the power supply capability (rating) of the DC power supply device 1. More severe load fluctuation monitoring is required. Specifically, when the rated power of the DC power supply device 1 is smaller than the maximum power consumption, the current consumption is monitored and the provisional as described above so as to cope with the situation where the load fluctuation is large as described above. It is desirable to perform control to shift to the power saving mode.

  Instead of comparing with current in this way, the power consumption may be calculated based on the current consumption, and the power consumption may be compared with a value obtained by subtracting a predetermined value from the rated power. Further, instead of these operations, the power saving mode transition conditions shown in FIG. 4 are determined for the operation of the DC power supply 1 and the operation of the AC power supply 1, respectively. By shifting the current under the power saving mode transition condition to a current (rated current) corresponding to the rated power of the DC power supply device 1, the transition to the power saving mode may be performed.

  As described above, in this embodiment, the charger circuit 4 monitors whether or not the AC power supply is supplied from the AC power supply device 2. When the AC power supply is not supplied, the charger circuit 4 notifies the power saving start control circuit 6 to save power. The power start control circuit 6 controls the CPU to perform throttling based on the notification. Therefore, power consumption can be quickly reduced after the supply of AC power is stopped. Therefore, when an electric load exceeding the rated power of the DC power supply device 1 is applied when driven by the AC power supply, even if the supply of the AC power supply is suddenly stopped, a predetermined time until switching to the driving of the DC power supply device 1 is performed. Since power consumption can be reduced in time, the DC power supply 1 can be driven in an electrical load state lower than the rated power of the DC power supply 1, and the portable computer can be used safely.

  As described above, the information processing device and the power saving control method according to the present invention are useful for an information processing device that operates by switching between an AC power source and a DC power source, and are particularly suitable for a portable information processing device.

1 DC power supply 2 AC power supply 3 EC
4 Charger circuit 5 CPU
6 Power saving start control circuit 7 LCD backlight control circuit 8 Chipset 9 Switching device 10, 11 Power line 12 AC cable

Claims (14)

An information processing apparatus comprising a computing means and capable of operating by switching between an operation using an external AC power supply and an operation using a DC power supply supplied by a DC power supply device incorporated therein,
AC power supply determining means for determining whether or not AC power is supplied;
A power saving start control means for controlling the arithmetic means to shift to a power saving state before the drive power supply is switched to a DC power supply when the AC power supply determining means determines that there is no supply of AC power;
A power control means for acquiring a temperature value and a consumption current value from the DC power supply device as battery information and canceling the power saving state when the battery information is less than a predetermined threshold;
An information processing apparatus comprising: The power control means acquires the current consumption value as the battery information from the DC power supply device, and determines whether or not the current consumption value is equal to or greater than a current value obtained by subtracting a predetermined value from the DC power supply rated current value. When it is determined that the current consumption value is equal to or greater than the current value, the released power saving state is restored.
The information processing apparatus according to claim 1 . The calculation means is a CPU,
The information processing apparatus according to claim 1 or 2, characterized in that the power-saving state to the CPU throttling state. Storage means for storing data,
And further comprising
The power saving start control means controls the storage means to shift to a power saving state when the AC power supply determination means determines that there is no supply of AC power.
The information processing apparatus according to claim 1 , 2, or 3 . A display device for displaying information,
And further comprising
The power saving start control means controls the display device to shift to a power saving state when the AC power supply determination means determines that there is no supply of AC power.
The information processing apparatus according to any one of claims 1-4, characterized in that. The display device is an LCD,
The power saving state of the display device is an LCD backlight extinguishing state, or an LCD backlight luminance reduction state,
The information processing apparatus according to claim 5 . An external storage device for storing data,
And further comprising
The power saving start control means controls the external storage device to shift to a power saving state when the AC power supply determination means determines that there is no supply of AC power.
The information processing apparatus according to any one of claims 1 to 6 . Input / output means for input / output to the arithmetic means;
Input / output control means for controlling input / output with respect to the input / output means;
And further comprising
The power saving start control means instructs the input / output control means to shift to a power saving state when the AC power supply determination means determines that there is no supply of AC power,
The input / output control means controls the input / output means to shift to a power saving state based on an instruction from the power saving start control means;
The information processing apparatus according to claim 1 , 2, or 3 . The input / output means is a storage means for storing data,
The information processing apparatus according to claim 8 . The input / output means is a display device for displaying information.
The information processing apparatus according to claim 8 or 9, characterized in that. The display device is an LCD,
Putting the input / output control means in a power saving state by thinning out a processing rate of an image to be displayed on the display device;
The information processing apparatus according to claim 10 . The input / output means is an external storage device for storing data,
The information processing apparatus according to any one of claims 8 to 11, wherein the. The maximum power consumption of its own device exceeds the rated power of the DC power supply,
The information processing apparatus according to any one of claims 1 to 12 . An AC power supply device for rectifying an AC power supply into a DC power supply;
Further comprising
The DC power supply and the AC power supply are built in the same casing.
The information processing apparatus according to any one of claims 1 to 13, characterized in that.

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