Power Managing Method For Avoiding Sudden Drop In Voltage And Electronic System Applying The Power Managing Method

Abstract

An electronic system (300) comprising: a battery (303); at least one electronic device; and a power managing unit (301), arranged for detecting a battery voltage of the battery (303), and arranged for limiting at least one performance of the at least one electronic device if the battery voltage is not higher than a first low threshold voltage.

Claims

1. A power managing method, applied to an electronic system comprising a battery and at least two electronic devices, comprising: (a) determining if at least two of the electronic devices in a predetermined list will simultaneously operate; and (b) limiting at least one performance of t at least one of the electronic devices when at least two of the electronic devices in the predetermined list will simultaneously operate.

2. The power managing method of claim 1, wherein the step (b) limits the performance of a second electronic device when the step (a) determines a first electronic device in the predetermined list is ready for operating and the second electronic device in the predetermined list does not operate yet.

3. The power managing method of claim 2, wherein the first electronic device is a communication device and the second electronic device is a flash.

4. The power managing method of claim 2, further comprising determining a battery current that will be supplied to the first electronic device, wherein the step (b) limits the performance of the second electronic device when the battery current that will be supplied to the first electronic device is not smaller than a threshold current.

5. The power managing method of claim 1, further comprising: detecting a battery voltage of the battery; and performing the step (a) and (b) when the battery voltage is not higher than a low threshold voltage.

6. An electronic system, comprising: a battery; at least two electronic devices; and a power managing unit, arranged for performing: (a) determining if at least two of the electronic devices in a predetermined list will simultaneously operate; and (b) limiting at least one performance of at least one the electronic devices if least two of the electronic devices in the predetermined list will simultaneously operate.

7. The electronic system of claim 6, wherein the power managing unit limits the performance of a second electronic device when the power managing unit determines a first electronic device in the predetermined list is ready for operating and the second electronic device in the predetermined list does not operate yet.

8. The electronic system of claim 7, wherein in the first electronic device is a communication device and the second electronic device is a flash.

9. The electronic system of claim 7, wherein the power managing unit determines a battery current that will be supplied to the first electronic device, wherein the power managing unit limits the performance of the second electronic device when the battery current that will be supplied to the first electronic device is not smaller than a threshold current.

10. The electronic system of claim 6, wherein the power managing unit detects a battery voltage of the battery, and performs the steps (a) and (b) when the battery voltage is not higher than a low threshold voltage.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG. 1 is a schematic diagram illustrating a conventional battery voltage drop issue.

[0019] FIG. 2 is a schematic diagram illustrating relations between a total battery current and a battery voltage.

[0020] FIG. 3 is a block diagram illustrating an electronic system according to one embodiment of the present invention.

[0021] FIG. 4 and FIG. 5 are schematic diagrams illustrating the operation for the electronic system depicted in FIG. 3, according to one embodiment of the present invention.

[0022] FIG. 6 is a flow chart illustrating the operation for the electronic system depicted in FIG. 3, according to one embodiment of the present invention.

[0023] FIG. 7 and FIG. 8 are flow charts illustrating power managing methods according to other embodiments of the present invention.

DETAILED DESCRIPTION

[0024] A power managing mechanism provided by the present invention will be described below. The power managing mechanism comprises a passive mode depicted in FIG. 4-FIG. 6, and an active mode depicted in FIG. 7, FIG. 8. The passive mode and the active mode can be applied simultaneously or independently.

[0025] FIG. 3 is a block diagram illustrating an electronic system according to one embodiment of the present invention. FIG. 4 and FIG. 5 are schematic diagrams illustrating the operation for the electronic system depicted in FIG. 3, according to one embodiment of the present invention. Please simultaneously refer to the FIG. 3/FIG. 4, or FIG. 3/FIG. 5, to understand the concept for the present invention for more clear.

[0026] As illustrated in FIG. 3, the electronic system 300 comprises a power managing unit 301, a battery 303, and a plurality of electronic devices D1, D2, D3, and D4. The power managing unit 301 detects a battery voltage Vbat of the battery 303. If the battery voltage Vbat is not higher than a first low threshold voltage VL1 (as illustrated in FIG. 4), the power managing unit 301 limits at least one performance of the electronic device D1, D2, D3, D4. In one embodiment, if the battery voltage Vbat is higher than the first low threshold voltage VL1, the power managing unit 301 does not limit the performance of the electronic device D1, D2, D3, D4.

[0027] In one embodiment, if the performance of the electronic device is already limited as depicted in the description of FIG. 4, the power managing unit 301 further detects if the battery voltage Vbat rises back to a high threshold voltage VH higher than the first low threshold voltage VL1 (as illustrated in FIG. 4), and releases the limiting for the performance of the electronic device if the battery voltage rises back to be higher than or equal to (not lower) the high threshold voltage VH.

[0028] In another embodiment, if the performance of the electronic device is limited, the power managing unit 301 detects if the battery voltage falls down to a second low threshold value VL2 (as illustrated in FIG. 5) lower than the first low threshold value (VL1). If the battery voltage falls down to be lower than or equal to (not higher) the second low threshold value VL2, the power managing unit 301 limits at least one performance of the electronic device to a level lower than a level of the embodiment depicted in FIG. 4. By this way, a total battery current smaller than which in FIG. 4 is provided.

[0029] In one embodiment, the power managing unit 301 reduces at least one following parameter of the electronic device D1, D2, D3, D4 to limit the performance of the electronic device D1, D2, D3, and D4: an operating voltage, an operating frequency, a battery current and a data transmitting power. In such embodiment, the above-mentioned operation “to a level lower than a level of the embodiment” depicted in FIG. 4 means providing a lower operating voltage, a lower operating frequency, a lower battery current and a lower data transmitting power to the electronic device.

[0030] Additionally, in one embodiment, the power managing unit 301 comprises a power detecting unit 305 for detecting the battery voltage Vbat, and executes a power managing program 307 to control the performances of the electronic devices, but not limited. Also, in one embodiment, the electronic device D1 is a CPU (central processing unit), the electronic device D2 is a communication device such as a modem or a Bluetooth device, the electronic device is a flash for a camera device, and the electronic device D4 is a backlight. However, the scope of the present invention is not limited to these embodiments.

[0031] FIG. 6 is a flow chart illustrating the operation for the electronic system depicted in FIG. 3, according to one embodiment of the present invention. The flow chart in FIG. 6 comprises:

[0032] Step 601

[0033] The electronic system normally operates. That is, the electronic system operates based on default settings.

[0034] Step 603

[0035] Enable low battery voltage detecting. That is, start to determine if the battery voltage is not higher than a low threshold voltage. In such case, the low threshold voltage is a first low threshold voltage VL1 (3.25 v in this example), which is set by the step 621.

[0036] Step 605

[0037] Trigger a first level low battery voltage state if the battery voltage Vbat is not higher than the first low threshold voltage VL1.

[0038] Step 607

[0039] Enable a first level low power throttling. That is, limit at least one performance of the electronic device for a first level.

[0040] Step 609

[0041] Limit the performance for the electronic devices listed in a predetermined list. In one embodiment, the predetermined list lists the electronic devices consuming a large battery current, for example, a CPU, a GPU (graphic processing unit), a flash (ex. for a camera device), a communication device, or a panel.

[0042] Step 611

[0043] Set the low threshold voltage to a second low threshold voltage VL2 (3.0 v in this example).

[0044] Step 613

[0045] Enable high battery voltage detecting. That is, start to determine if the battery voltage rises to be higher than or equal to a high threshold voltage VH. Please note the battery voltage is also detected to determine if the battery voltage falls down to be lower than or equal to the low threshold voltage, which is now the second low threshold voltage VL2.

[0046] If the battery voltage rises to be higher than or equal to (i.e. not lower) than a high threshold voltage VH, then go to the step 619. On the opposite, if the battery voltage falls down to be lower than or equal to (i.e. not higher) than the second low threshold voltage VL2, then go to the step 615.

[0047] Step 615

[0048] Trigger a second level low battery voltage state if the battery voltage Vbat is not higher than the second low threshold voltage VL2.

[0049] Step 617

[0050] Enable a second level low power throttling. That is, limit at least one performance of the electronic device for a second level. The second level is higher than the first level of the step 605. In other words, the performances of the electronic devices are limited more strictly in the step 617 than in the step 607. After the step 617, goes to the step 609.

[0051] Step 619

[0052] Trigger a high battery voltage state. That is, the battery voltage Vbat is not lower than the high threshold voltage VH.

[0053] Step 621

[0054] Set the low voltage level to the first low threshold voltage VL1 (3.25 v in this example).

[0055] Step 623

[0056] Disable low power throttling. That is, do not limit the performances for the electronic devices.

[0057] A power managing method according to above-mentioned embodiments can be summarized as: a power managing method, applied to an electronic system comprising a battery and at least one electronic device, comprising: (a) detecting a battery voltage of the battery; and (b) limiting at least one performance of the at least one electronic device when the battery voltage is not higher than a first low threshold voltage. Other detail steps can be acquired according to above-mentioned embodiments, thus are omitted for brevity here.

[0058] Embodiments for the active mode will be described as below. FIG. 7 and FIG. 8 are flow charts illustrating power managing methods according to other embodiments of the present invention. The methods depicted in FIG. 7 and FIG. 8 can be performed by the power managing unit in FIG. 3 as well. The embodiment in FIG. 7 comprises the following steps:

[0059] Step 701

[0060] Acquire remaining power information of the battery.

[0061] Step 703

[0062] Electronic devices perform requested functions. For example, if the electronic device is a CPU, the electronic device process requested tasks.

[0063] Step 705

[0064] Determine if remaining power of the battery is lower than or equal to (i.e. not higher) a threshold value (ex. 15% of the full battery power). If yes, go to step 707. If not, do not change the operating frequency of the CPU and goes back to the step 703.

[0065] Step 707

[0066] Reduce the operating frequency of the CPU.

[0067] Please note the steps depicted in FIG. 7 are not limited to be applied to a CPU, and can be applied to other electronic devices as well. Accordingly, an power managing method based on the embodiment of FIG. 7 can be summarized as: A power managing method, applied to an electronic system comprising a battery and at least one electronic device, comprising: (a) determining if remaining power of the battery is not higher than a threshold value (ex. based on remaining power information acquired in the step 701); and (b) limiting at least one performance of the at least one electronic device when the remaining power is not higher than a threshold value(ex. the steps 705, 707).

[0068] The following parameters can be reduced to limit at least one performance of the at least one electronic device: an operating voltage, an operating frequency, a battery current and a data transmitting power.

[0069] The embodiment in FIG. 8 discloses an embodiment which limiting at least one performance for one of the electronic devices while at least two the electronic devices simultaneously operate. In this embodiment, one electronic device is a flash of a camera device, and the other electronic is a communication device. Also, the communication device is requested to transmit data while the flash is ready to operate. FIG. 8 comprises the following steps:

[0070] Step 801

[0071] A user enables a preview mode of a camera device. For example, a mobile phone comprises a camera device, and the user activates the camera, uses the screen for the mobile phone to preview a photo that the camera will shot.

[0072] Step 803

[0073] The user enables the camera device to prepare shooting. For example, the user touches the screen to focus on an object that will be shot by the camera device. A flash, such as an LED (light emitting diode) included in the mobile phone, may also emit light if a photo is shot.

[0074] Step 805

[0075] Determine if a battery current provided to the flash for emitting light will be larger than or equal to (i.e. not smaller) than a threshold current. If yes, go to step 807. If not, go to step 806.

[0076] Step 806

[0077] Do not change the performance of the communication device.

[0078] Step 807

[0079] Limit the performance of the communication device. In one embodiment, reduce the data transmitting power of the communication device to limit the performance of the communication device.

[0080] Step 809

[0081] The flash emits light.

[0082] Step 811

[0083] The camera shoots a photo.

[0084] Step 813

[0085] The flash stops emitting light.

[0086] Step 815

[0087] Recover the transmitting power of the communication device.

[0088] For the embodiment depicted in FIG. 8, the flash and the communication device are all devices listed in a predetermined list, which means the electronic device will consume a large battery current. If such devices simultaneously operate, the battery voltage may significantly drop. Accordingly, the transmitting power of the communication device is reduced when the flash is ready for operating (steps 807, 809, 811).

[0089] Please note the embodiment in FIG. 8 is not limited to be applied to a flash and a communication device. Accordingly, the embodiment depicted in FIG. 8 can be summarized as: a power managing method, applied to an electronic system comprising a battery and at least one electronic device, comprising: (a) determining if at least two of the electronic device in a predetermined list will simultaneously operate; and (b) if yes, limit at least one performance of the at least one electronic device. In one embodiment, if the step(a) determines a first electronic device in the predetermined list is ready for operating (ex. the flash) and a second electronic device does not operate yet(ex. the communication device), the step (b) limits the performance of the second electronic device. Furthermore, in one embodiment, such power managing method is performed if the battery voltage is not higher than a low threshold voltage.

[0090] In view of above-mentioned embodiments, a peak for the total battery current can be avoided since a total battery current provided to electronic devices can be well controlled. By this way, the sudden drop issue for the battery voltage can be improved.

[0091] Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.