JPH07141075A - Power saving control method for portable computer - Google Patents

Abstract

PURPOSE:To automatically control the luminance of a back light at the optimum level depending on whether an external power source or internal battery is used by controlling the luminance of the back light of an LCD display device at the maximum level when the external power source is used and a level lower than the maximum level when the internal battery is used. CONSTITUTION:When a power source is applied, it is judged whether or not the internal battery 13 is used from power source state information 19, and when the internal battery 13 is used, back light luminance information which supplies luminance of low level is taken out by reading the back light luminance information stored in memory in advance in a main memory device 6, and the luminance can be set by sending it to a back light luminance adjusting mechanism 11. while, when the external power source 12 is used, the luminance can be set by sending the back light luminance information which supplies the maximum luminance to the back light luminance adjusting mechanism 11. In this way, it is possible to freely set balance with battery operating time at need.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an L with a backlight.
The present invention relates to a power-saving control method when a built-in battery is used in a portable computer that uses a CD as a display device and also uses two built-in batteries. Especially when an external power supply is used, the brightness of the backlight is increased to make the LCD display easier to see. It sometimes relates to improvement of the power saving method of reducing the brightness of the backlight to reduce power consumption.

When a portable computer is operated by a built-in battery, the brightness of the LCD backlight is reduced in order to save power consumption. However, if the brightness level in this case is fixed, the LCD display is fixed. May be difficult to see and may be inconvenient. It is desirable to be able to arbitrarily set a bright brightness level according to the situation, such as when the computer is used for a short time.

[0003]

2. Description of the Related Art In recent years, most portable computers are equipped with an LCD display device with a backlight, but the backlight consumes a large amount of power to improve the visibility of the LCD, and the battery operating time cannot be extended. It is one of the factors.

Under such circumstances, it has been attempted to extend the operation time by reducing the brightness of the backlight during battery operation. An example of power saving control in a conventional portable computer will be described with reference to FIG.

In FIG. 6, 1 is a portable computer,
Reference numeral 2 is a main body device, 3 is an LCD display device, and 4 is a power supply control unit. The main body device 2 includes a CPU 5, a main storage device 6, and a keyboard 7. In addition, the LCD display device 3 is L
It is composed of a CD 9, a backlight 10, and a backlight brightness adjusting mechanism 11. Display information output from the main body device 2 is input to the LCD 9 for display, and the backlight 10 illuminates the LCD 9 from the rear surface to make the display easy to see. The backlight brightness adjusting mechanism 11 has a mechanism for changing the brightness level of the backlight 10 to 100% or 50%, for example.

Further, the power supply control unit 4 is provided with a power supply switching mechanism 14, which selects either an external power supply (100V AC) 12 or an internal battery 13 as a power supply source to supply power to the main body device 2 and the LCD display device 3. To supply. For simplification of description, a rectifier, a DC-DC converter (regulator), and the like that the power supply control unit 4 normally includes are not shown in the figure but are naturally included. The power is turned on and off by the power switch 15. The power supply switching mechanism 14 selects and uses the external power source 12 or the internal battery 13 designated by the external / internal switch 16. Further, instead of the external / internal switch 16, the power supply status from the external power supply is automatically detected, and if the power is supplied, the external power is used, and if not, the internal battery is used. In some cases, it is equipped with a switching mechanism.

A signal indicating the usage state of the power source selected by the power supply switching mechanism 14 is sent to the backlight brightness adjusting mechanism 11 of the LCD display device 3 and is used for controlling the brightness of the backlight. In the illustrated example, the backlight brightness adjusting mechanism 11 can perform only two-step adjustment of 100% and 50%, and the status signal output when the power supply switching mechanism 14 is using the internal battery 13 is The signal becomes a signal for instructing the backlight brightness adjusting mechanism 11 to have a brightness of 50%, and the backlight brightness adjusting mechanism 11 operates in response to this signal in a hardware manner to reduce the brightness of the backlight 10 to 50%. .

[0008]

In the conventional power saving method,
For example, the control for detecting whether the power source is an external power source or the internal battery and unconditionally reducing the brightness to 50% in the battery operation is constructed only by the hardware without using the program in the main memory.

In this method, since the brightness during battery operation is uniformly regulated, the operator wants to increase the brightness of the backlight to make it easier to see, or to decrease the brightness of the backlight to extend the battery operation time. Could not be realized.

The present invention relates to an L in a portable computer.
It is possible to automatically control the brightness of the backlight of the CD display device to the optimum level depending on whether the external power source is used or the internal battery is used, and to change it to an arbitrary level from the outside when necessary. Has an aim.

[0011]

[Means for Solving the Problems] Since the control contents for the brightness of the backlight are fixed because it is composed only of conventional power saving means hardware, it is difficult to flexibly respond to the situation. The invention aims to solve the problem by interposing the software of the main body device in the power saving means, thereby facilitating the level setting of the backlight brightness and the setting change from the outside.

The principle of the power saving control method of the present invention will be described with reference to FIG. In FIG. 1, reference numeral 1 denotes a portable computer having an LCD display device with a backlight and capable of switching between an external power source and an internal battery, and in particular, the figure shows a power saving control mechanism therein.

Reference numeral 2 is a main unit having various program processing functions. Reference numeral 3 is an LCD display device using an LCD with a backlight. Reference numeral 4 is a power supply control unit that can switch between an external power supply and an internal battery.

Reference numeral 5 is a CPU. Reference numeral 6 is a main storage device. 7 is a keyboard.

Reference numeral 8a denotes a backlight brightness control function implemented by software on the CPU 5 of the hardware and the main storage device 6, and detects the power status of a predetermined condition to detect the brightness of the corresponding backlight. The control for determining the level and setting the LCD display device 3 is performed.

8b is a backlight brightness information external setting function which is realized by software as in the case of 8a, and allows the backlight brightness information to be arbitrarily set through a dialogue with an operator. The backlight brightness information set here is notified to the backlight brightness control function 8a, held therein, and used when the backlight brightness of the LCD display device 3 is set.

Reference numeral 9 is an LCD. Reference numeral 10 denotes a backlight that illuminates the LCD 9 from behind. Reference numeral 11 denotes a backlight brightness adjustment mechanism that digitally adjusts the brightness level of the backlight 10 based on the backlight brightness information of binary data set by the backlight brightness control function 8a of the main body device 2.

Reference numeral 12 is an external power source of commercial AC100V, for example. Reference numeral 13 is an internal battery housed in the portable computer 1. Reference numeral 14 is a power supply switching mechanism that switches between the external power supply 12 and the internal battery 13.

Reference numeral 15 is a power switch for turning the power on and off. Reference numeral 16 denotes an external / internal switch for instructing the power supply switching mechanism 14 whether the power source to be selectively used is the external power source 12 or the internal battery 13.

Reference numeral 19 is power state information for notifying the backlight brightness control function 8a whether the power source selected by the power source switching mechanism 14 is the external power source 12 or the internal battery 13.

The backlight brightness control function 8a sends brightness information to the backlight brightness adjusting mechanism 11 under the following conditions to set the brightness of the backlight 10 or change the setting. When the power is turned on (including the recovery from the resume state), when the external power source is switched to the internal battery, or when the internal battery is switched to the external power source, the backlight brightness information external setting function 8b notifies the brightness information change. If

Of the brightness information used for setting the backlight brightness adjusting mechanism 11 in each of the cases ,, at least the brightness information which gives the low level backlight brightness when the internal battery is used is previously stored. It is set by using the light brightness information external setting function 8b, notified to the backlight brightness control function 8a, and held. A non-volatile auxiliary storage device (not shown) such as a hard disk is used to hold the brightness information. On the other hand, the brightness information that gives a high level of backlight brightness when using an external power supply can be fixed so as to give the maximum brightness.

[0023]

The power saving method of the present invention will be described with reference to FIG. First, the portable computer 1 is in a power-off state or a resume state (a state in which the information indicating the CPU state immediately before the power-off and the content of the main memory are held although the power is turned off. Later, the state of the CPU immediately before power-off and the contents of the main memory are restored so that the operation can be continued.

When the power switch 15 is turned on and the power is turned on, the power control unit 4 is activated, and the power supply switching mechanism 14 selects the input power on the side instructed by the external / internal switch 16. Power is supplied to the main body device 2 and the LCD display device 3. At this time, the power supply state information 19 indicates whether the input power supply on the selected side is “external” or “internal”.

When power is supplied to the main body device 2, the main body device 2 starts the initialization process, and first the backlight brightness control function 8a is activated. The backlight brightness control function 8a reads the power supply state information 19 and detects whether the power supply state is "external" or "internal". When the power status is "external", it is not necessary to save power consumption, and the LCD display is easy to see.
For example, the highest level brightness is set, and the brightness information is sent to the backlight brightness adjustment mechanism 11 to adjust the brightness of the backlight 10 to the maximum.

On the other hand, when the power supply state is "internal", power saving of the battery is delayed, so that, for example, the backlight brightness control function 8a is preset to output backlight brightness information of 50% level. And then
The backlight luminance information is sent to the backlight luminance adjusting mechanism 11 so that the backlight 10 emits light at a level as low as 50% of the maximum luminance.

Here, the operator (user) is dissatisfied with the current 50% level brightness of the backlight 10 from the environment in which the computer is used, and wants to raise the brightness of the backlight 10 a little more even if the power saving effect is reduced to some extent. In such a case, the backlight brightness information external setting function 8b is called and the desired brightness level, for example, 7
The brightness information indicating the 0% level is set and input. This input brightness information is notified to the backlight brightness control function 8a, and the backlight brightness control function 8a sends this to the backlight brightness adjustment mechanism 11 to bring the brightness of the backlight 10 to the corresponding 70% level. increase. The brightness information input at this time is the backlight brightness control function 8a.
The previous luminance information is retained so as to be updated, and this information is used until it is updated again thereafter.

In this way, the LCD backlight 10 is used.
The brightness of the computer is adjusted and the operation of the computer is started, but during the operation, the internal battery 13 is exhausted, or the computer is moved to a place where an external power source cannot be taken, so that the power source is switched between external and internal. There are cases. In such a case, the content of the power supply status information 19 output from the power supply switching mechanism 14 changes. Backlight brightness control function 8a
Detects the switching of the power source and sends the backlight luminance information corresponding to the new situation to the backlight luminance adjusting mechanism 11 to change the luminance of the backlight 10.

If the internal battery 13 is switched to during operation with the external power supply 12, the backlight brightness control function 8a detects this from the power supply status information 19 and saves power in advance. For example, the backlight brightness information at a low level, for example, 50% level is read out and sent to the backlight brightness adjusting mechanism 11 to, for example, reduce the brightness of the backlight 10, which is currently the maximum brightness, to the 50% level. Further, in this case, when the obtained luminance is unsatisfactory, the backlight luminance information external setting function 8b is called to change the backlight luminance information arbitrarily as described above when the power is turned on. be able to.

On the other hand, when switching to the external power source 12 is performed during operation of the internal battery 13, the backlight brightness control function 8a detects this from the power status information 19 and detects the current brightness, for example, Instead of the brightness at the 50% level, backlight brightness information for making the brightness at the 100% level maximum is sent to the backlight brightness adjustment mechanism 11 to increase the brightness of the backlight 10.

In this way, the brightness of the backlight can be automatically set to the one corresponding to each power source in response to the state of the external / internal power source immediately after power-on or during operation. Moreover, it is possible to arbitrarily set the brightness that is convenient for the operator according to the usage environment of the computer and the situation such as the length of the processing time.

[0032]

Embodiments of the present invention will be described with reference to FIGS. FIG. 2 shows the configuration of the portable computer according to the embodiment of the present invention. The configuration shown in FIG. 2 is almost the same as the configuration of FIG. 1, but in FIG. 2, the backlight luminance control function 8a and the backlight luminance information external setting function 8b of FIG.
A backlight brightness control program 17 and a backlight brightness information external setting program 18 are used to specifically realize the above. These programs 17 and 18 are loaded on the main memory 6 and the CP
It is executed by U5. Reference numeral 20 denotes backlight luminance information that is referred to and updated by the backlight luminance control program 17, and includes luminance information that gives the maximum luminance and luminance information that gives a lower level luminance. The former brightness information is fixed here, and only the latter brightness information is updated when notified from the backlight brightness information external setting program 18.

The backlight brightness control program 17 is
It is executed when the power is turned on and when the external / internal power is switched. As a method of detecting the occurrence of power source switching, the CPU when the power source switching mechanism 14 switches the power source is used.
5, the method of making the backlight brightness control program 17 read the power supply status information 19 and the method of making the power supply status information 19 read and detected at the time of the start of the processing in the main body device 2 and the screen switching, etc. is there.

The backlight brightness information external setting program 18 basically sets constants interactively, and can be prepared as a utility.
An interface is provided between the two programs in order to pass the brightness information input using the backlight brightness information external setting program 18 to the backlight brightness control program 17.

As for the functional operation of each of the other elements in FIG. 2, the above description of the corresponding elements in FIG. 1 is incorporated. FIG. 3 shows the overall control flow of the backlight brightness control program 17 in FIG. 2, and blocks (a) to (d) in the figure show the control functions as elements. In FIG. 3, when the power is turned on from the power-off state (including the resume state) of the computer, the control function (a) is first executed, and the backlight luminance information 20 is initialized to the backlight luminance adjusting mechanism 11. To be done. When the external power supply is switched to the internal battery during the subsequent operation, the control function (b) is executed.

When the internal battery is switched to the external power source, the control function (c) is executed, and the backlight brightness information external setting program 18 shown in FIG.
When the luminance information is input by, the control function (d) is executed.

FIG. 4 is a flow of the backlight luminance information external setting program 18. To explain the flow of FIG. 4, when the operator wants to change the setting of the brightness information by himself, the operator setting view is called on the screen and the brightness information of the value desired by the operator is set on the screen. The brightness information thus set is notified to the backlight brightness control program 17.

FIG. 5 shows details of the control functions (a) to (d) of each element shown in the overall flow of the backlight brightness control program of FIG. The flows (a) to (d) in FIG. 5 correspond to the control functions (a) to (d) in FIG. 3, respectively.

The flow of FIG. 5A shows the setting control when the power is turned on. First, whether the internal battery 13 is used (Y) or not (N) is determined from the power status information 19, and when the internal battery 13 is used (Y),
Backlight brightness information stored in advance in a non-volatile memory (not shown, the same applies below) is read into the main storage device 6 to retrieve the backlight brightness information that gives a low level brightness for the internal battery use state, and It is sent to the backlight brightness adjusting mechanism 11 of the wear to set the brightness.
On the other hand, when the internal battery 13 is not used (N), that is, when the external power source 12 is used, the fixed fixed backlight brightness information that gives the maximum brightness is sent to the backlight brightness adjustment mechanism 11. To set the brightness.

The flow of FIG. 5B shows the setting control when switching from the external power source to the internal battery. In this case as well, low-level brightness information corresponding to the usage state of the internal battery 13 is read from the above-mentioned non-volatile memory and sent to the backlight brightness adjustment mechanism 11 for hardware setting.

The flow of FIG. 5C is the flow of setting control when switching from the internal battery to the external power source. Here, in correspondence with the usage state of the external power supply 12,
Fixed brightness information that gives the maximum brightness is sent to the backlight brightness adjustment mechanism 11 for hardware setting.

The flow of FIG. 5D is a flow of setting control at the time of setting luminance information from the outside. Here, FIG.
2, the brightness information notified from the backlight brightness information external setting program is written in the above-mentioned non-volatile memory, and the brightness information is sent to the backlight brightness adjusting mechanism 11 for hardware setting.

[0043]

As described above, according to the present invention, it is possible to make the brightness variable during the operation of the internal battery, and the operator can balance the readability of the display contents during the operation of the internal battery with the battery operation time. It can be set freely.

[Brief description of drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a configuration diagram of a portable computer according to an embodiment of the present invention.

FIG. 3 is an overall flow of a backlight brightness control program in the embodiment of the present invention.

FIG. 4 is a flow of a backlight luminance information external setting program in the embodiment of the present invention.

FIG. 5 is a detailed flow of a brightness control program in the embodiment of the present invention.

FIG. 6 is an explanatory diagram of power saving control in a conventional portable computer.

[Explanation of symbols]

 1 Portable Computer 2 Main Unit 3 LCD Display Device 4 Power Supply Control Unit 5 CPU 6 Main Memory Device 7 Keyboard 8a Backlight Brightness Control Function 8b Backlight Brightness Information External Setting Function 9 LCD 10 Backlight 11 Backlight Brightness Adjustment Mechanism 12 External Power supply 13 Internal battery 14 Supply power switching mechanism 15 Power switch 16 External / internal switch 19 Power status information

Claims (3)

[Claims] 1. A main body device (2) including a CPU, an LCD with a backlight and an LCD display device (3) including a backlight brightness adjusting mechanism for adjusting the brightness of the backlight, an external power source and an internal battery. In a portable computer having a power supply control unit (4) including a power supply source switching mechanism for switching, a backlight brightness control function (8a) and a backlight brightness information external setting function (8b) are provided in a main body device (2). When the power is turned on, the backlight brightness control function (8a) checks whether the power supply control unit (4) uses the external power supply or the internal battery, and the external power supply is used. In this case, the brightness of the backlight of the LCD display device (3) is controlled to the maximum level, while when the internal battery is in use, The backlight brightness of the LCD display device (3) is controlled to a level lower than the maximum level, and the backlight brightness information external setting function (8b) makes it possible to change the brightness of the backlight at the low level from the outside. A power saving control method for a portable computer, comprising: 2. A main body device (2) including a CPU, an LCD with a backlight and an LCD display device (3) including a backlight brightness adjusting mechanism for adjusting the brightness of the backlight, an external power source and an internal battery. In a portable computer provided with a power source control unit (4) including a power supply source switching mechanism for switching, a backlight brightness control function (8a) and a backlight brightness information external setting function (8b) are provided in a main body device (2). By the way, while the power source control unit (4) is operating in the state of using the external power source, the backlight brightness control function (8a) allows the power source control unit (4) to change from the internal state of the external power source to the internal state. When the switching to the use state of the battery is detected, and when the switching is detected, the brightness of the backlight of the LCD display device (3) is controlled to a low level. Moni, the by backlight luminance information external setting function (8b), power-saving control method of a portable computer, characterized in that the brightness of the low level of the backlight can be changed from the outside. 3. The power supply control according to claim 1, wherein the backlight brightness control function (8a) controls the power supply while the power supply control unit (4) is operating in a state where an internal battery is used. When the switching of the state of use of the internal battery in section (4) to the state of use of the external power supply is detected, and when the switching is detected, control is performed to raise the brightness of the backlight of the LCD display device (3) to the maximum level. A power-saving control method for a portable computer, comprising: