Patent Publication Number: US-9846465-B2

Title: Electronic device configured to control a charging prohibiting period of a battery of a second electronic device

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application claims priority from US Provisional Patent Application No. 62/103,521 filed on Jan. 14, 2015, the entire contents of which are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     An embodiment of the present invention relates to an electronic device which controls a charging prohibiting period of a battery in, for instance, a KB Dock side. 
     BACKGROUND ART 
     In manufacturing a 2 in 1 note PC in which a built-in battery (hereinafter, referred to as a 2nd battery) is mounted on a Keyboard Dock (hereinafter, referred to as a KB Dock), even in a case where the PC is separated to only the KB Dock, when the KB Dock 2nd Battery is charged, a PeakShift function which stops a charging from an AC adapter and switches into a battery driving so as to suppress a power consumption is necessary in a time period which is high in a power consumption. However, the way of coping with such a demand has not been known yet. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing an external appearance of an electronic device of an embodiment. 
         FIG. 2  is a diagram showing a first using style of the electronic device of the embodiment. 
         FIG. 3  is a diagram showing a second using style of the electronic device of the embodiment. 
         FIG. 4  is a diagram showing a system configuration of the electronic device of the embodiment. 
         FIG. 5  is a schematic configuration diagram showing main parts of the embodiment. 
         FIG. 6  is a sequence diagram showing operations of the main parts of the embodiment. 
         FIGS. 7A and 7B  are diagrams which explain an IIC (I 2 C) interface used in the embodiment. 
         FIG. 8  is a sequence diagram showing operations of main parts used in another embodiment. 
     
    
    
     MODE FOR CARRYING OUT THE INVENTION 
     An embodiment of the present invention will be described below. 
     (First Embodiment) 
     A first embodiment will be described by referring to  FIG. 1  to  FIG. 7 . 
       FIG. 1  is a perspective view showing an external appearance of an electronic device according to an embodiment. The electronic device is, for instance, a portable electronic device which allows a handwritten input by a pen or a finger. In the following, it is assumed that the electronic device is realized as a tablet computer  1 . 
     As shown in  FIG. 1 , the tablet computer  1  includes a touch screen display  11 . The touch screen display  11  is attached to be overlapped on an upper surface of the tablet computer  1 . The touch screen display  11  includes a flat panel display and a sensor configured to detect a contact position of a pen or a finger on a screen of the flat panel display. The flat panel display is, for instance, a Liquid Crystal Display device (LCD). The sensor is, for instance, an electrostatic capacity type touch panel or an electromagnetic induction type digitizer. In this embodiment, it is assumed that two kinds of sensors, i.e. the digitizer and the touch panel are built in the touch screen display  11 . 
     As shown in  FIG. 1 , the tablet computer  1  is configured such that an extension unit  2  mounted thereon a keyboard can be connected thereto as necessary. In the following explanation, the extension unit  2  is referred to as a keyboard dock  2 . That is, the tablet computer  1  can be used in two kinds of styles including a state of a single main body (the keyboard dock is not connected) as shown in  FIG. 2  and a state where the keyboard dock  2  is connected thereto as shown in  FIG. 3 . The state shown in  FIG. 2  is referred to as a tablet mode. On the other hand, the state shown in  FIG. 3  is referred to a clam shell mode. 
       FIG. 4  is a diagram showing a system configuration of the tablet computer  1 . Components relating to a power control which include the extension unit  2  will be described below by referring to  FIG. 5 . 
     As shown in  FIG. 4 , the tablet computer  1  includes a CPU  101 , a system controller  102 , a main memory  103 , a graphics controller  104 , an RGB connector  104 A, an HDMI (a registered trademark) (High-Definition Multimedia Interface) output terminal  104 B, a BIOS-ROM  105 , an SSD (Solid State Drive)  106 , a USB connector  107 , an LAN device  108 , a wireless communication device  109 , an EC/KBC (Embedded Controller/Keyboard Controller)  110  and a docking port  111 . 
     The CPU  101  is a processor which controls operations of various kinds of modules in the tablet computer  1 . The CPU  101  loads various kinds of programs in the main memory  103  from the SSD  106  to execute the programs. The programs executed by the CPU  101  include an Operating System (OS)  200  or an environment setting utility program  210  (described below) which operates under the control of the OS  200 . 
     The CPU  101  also executes a Basic Input and Output System (BIOS [hereinafter, also referred to as a BIOS  250 ]) stored in the BIOS-ROM  105 . The BIOS  250  is a program which controls hardware. 
     The system controller  102  is a device which connects a local bus of the CPU  101  to various kinds of components. The system controller  102  includes therein a memory controller which controls an access of the main memory  103  and a serial ATA controller which controls an access of the SSD  106 . Further, the system controller  102  has a function for executing a communication with the graphics controller  104  and the EC/KBC  110  through a serial bus. 
     The graphics controller  104  is a display controller which controls an LCD  11 A used as a display monitor of the tablet computer  1 . The graphics controller  104  generates display signals (LVDS signals) to be supplied to the LCD  11 A from display data output by the various kinds of programs. The graphics controller  104  can generate an analog RGB signal and an HDMI video signal from the display data. The analog RGB signal is supplied to an external display through the RGB connector  104 A, and the HDMI video signal is supplied to the external display through the HDMI output terminal  104 B. The HDMI output terminal  104 B is a terminal which can transmit the HDMI video signal (the non-compressed digital video signal) and a digital audio signal by one cable. The graphics controller  104  can also transmit the analog RGB signal and the HDMI video signal to the keyboard dock  2  through the docking port  111 . The docking port  111  is a port for electrically connecting the tablet computer  1  to the keyboard dock  2 . 
     The LCD  11 A displays a screen image in accordance with the display signal supplied from the graphics controller  104 . In an upper layer of the LCD  11 A, a touch panel  11  B is arranged as a first sensor which detects the contact position of a finger on the screen. Further, in a lower layer of the LCD  11 A, a digitizer  11 C is arranged as a second sensor which detects the contact position of the pen on the screen. The touch panel  11 B is an electrostatic capacity type pointing device. The touch panel  11 B detects the contact position on the screen with which the finger comes into contact and movement of the contact position. On the other hand, the digitizer  11 C is the electromagnetic induction type pointing device. The digitizer  11 C detects the contact position on the screen with which the pen comes into contact and movement of the contact position. 
     The USB connector  107  is a connector which connects a USB device, for instance, a USB memory. The LAN device  108  is a device which executes a wired communication based on, for instance, an IEEE 802.3 standard. A connection of the tablet computer  1  to an LAN is executed by connecting a LAN cable to a LAN connector provided in the keyboard dock  2  side to be connected to the docking port  111 . The wireless communication device  109  is a device which executes a wireless communication based on, for instance, an IEEE 802.11g standard. 
     The EC/KBC  110  is an electric power management controller which executes a management of an electric power of the tablet computer  1  and has a function which turns on or turns off a power source of the tablet computer  1  in accordance with an operation of a power button by a user. 
     Further, an EC/KBC  301  is an electric power management controller which executes a management of an electric power of the keyboard dock  2 . The EC/KBC  301  includes therein a keyboard controller which controls a keyboard mounted on the keyboard dock  2 . Further, the EC/KBC  301  is configured to control a back light of the keyboard dock  2  or an LED which displays a state of an electric power. 
     Now, it is assumed that the power of the tablet computer  1  is turned on under a state where the keyboard dock  2  is connected to the docking port  111 . When the power of the tablet computer  1  is turned on, the BIOS  250  executes a POST (Power On Self Test). The BIOS  250  checks various kinds of components of the tablet computer  1  by the POST to initialize settings of the various kinds of components. In the POST, the BIOS  250  recognizes that the keyboard dock  2  is connected to the tablet computer and obtains a Dock-ID from the keyboard dock  2 . Then, the tablet computer  1  activates the OS  200 . In the tablet computer  1 , when the OS  200  is activated, the environment setting utility program  210  is activated under the control of the OS  200 . 
     When the environment setting utility program  210  is activated, the environment setting utility program  210  obtains the Dock-ID of the keyboard dock  2  from the BIOS  250 . The environment setting utility program  210  includes a Peakshift application  210 A (not shown), which is described below. The Peakshift application  210 A is configured as an application which obtains peak shift information (including a start/end time for setting a peak shift) from the tablet computer  1  or an external part (for instance, a network environment or the USB device). 
       FIG. 5  is a functional configuration diagram showing main parts of the electronic device of the embodiment. A system is assumed where an example of an information device (the electronic device) on which a plurality of batteries are mounted corresponds to a Tablet device and a Dock shown in  FIG. 5  and the Tablet device and the Dock include batteries, respectively. 
     In the tablet computer  1  which is the Tablet device, a constant voltage source is supplied by an AC adapter  150  connected as an external power source by using, for instance, a commercial alternating current as an ADP line. The AC adapter  150  is configured with elements which include a rectifier using a transformer, a diode bridge, a smoothing capacitor and the like. The constant voltage source is supplied to a Tablet Charger  143 A through a backflow prevention diode D 1  and a switch SW 1  and can be also supplied to a system SY (an electric/electronic functional part of the tablet computer  1  except for the elements shown in  FIG. 5 ). 
     The Tablet EC (1st EC/KBC)  110  is configured to execute a charging and discharging control communication with a battery B 1  and the Tablet Charger  143 A. For instance, when a firmware of the Tablet EC  110  charges the battery B 1 , the firmware determines a start/stop of charging of the battery B 1  by determining a state of a (Gas Gauge) IC ( 52 A) in the battery B 1 . This IC ( 52 A) is an IC configured to provide information about various kinds of states of a battery cell in the battery B 1  to a host (the firmware). 
     In the keyboard dock  2  which is the Dock, the constant voltage source similarly relates to a supply of an electric power to a Dock Charger  143 B. 
     The Dock EC (EC/KBC)  301  is configured to execute a charging and discharging control communication with a battery B 2  and a Dock Charger  143 B. For instance, when a firmware of the Dock EC  301  charges the battery B 2 , the firmware determines a start/stop of charging of the battery B 2  by determining a state of a (Gas Gauge) IC ( 52 B) in the battery B 2 . This IC ( 52 B) is an IC configured to provide information about various kinds of states of a battery cell in the battery B 2  to a host (the firmware). 
     The EC/KBC  301  controls a lighting of the keyboard (not shown). The keyboard includes a backlight (not shown). The backlight is controlled to be turned on and off by the EC/KBC  301 . 
     A switch SW 2  is configured to supply an electric power to the system SY from either the battery B 1  or the battery B 2  in accordance with, for instance, the environment setting utility program  210 . A communication between the Table EC  110  and the Dock EC  301  is executed by an IIC interface (described below). 
     In a technical background of the present embodiment, “in a certain device model, a 2nd battery and an EC/KBC (hereinafter, referred to as a 2nd EC/KBC) are mounted on a KB Dock. Thus, a function is necessary that supply of an electric power is stopped from an AC adapter in a time period in which a power consumption is high to suppress the power consumption by switching to a 2nd battery driving”. 
     That is, a problem arises so far that “since any mechanism of controlling a charging period of the 2nd battery is not provided, the 2nd battery is charged even during the time period in which a power consumption is high”. A method for solving the problem includes the following three items. The three items will be described below by referring to a sequence shown in  FIG. 6 .
     (1) When a power source of a PC system is turned ON in a docking state, the Peakshift application transmits Peakshift start and end times to the EC via the BIOS. The BIOS calculates a time from a present time based on the information received from the application and sets the time up to that time to the 1st EC. The 1st EC transmits the received information to the 2nd EC. The 1st EC and the 2nd EC start timers and respectively count down.   (2) Thereafter, even in an undock state, when it becomes a Peakshift setting start time, the 2nd EC executes a battery charging stop process at the set time irrespective of a docking/undock state.   (3) When it becomes a Peakshift end time, the 2nd EC executes a battery charging start process at the set time.   

     At timing P when the power source is turned ON, the Peakshift application  210 A transmits the peak shift information (the start/end time for setting the Peakshift) to the BIOS. The BIOS calculates the Peakshift start and end time by using these times and transmits the Peakshift start and end time to the 1st EC  110 . The 1st EC  110  transmits the Peakshift start and end time to the 2nd EC  301 . 
     When it becomes the Peakshift start time Ps, an AC driving is switched to a 2nd battery driving under both docking and undock states. 
     Further, when it becomes the Peakshift end time Pe, the 2nd battery driving is switched to return to the AC driving. 
       FIGS. 7A and 7B  are diagrams which explain the IIC interface. A bus (IIC-BUS) of the IIC interface includes two communication lines for a clock output to be pulled up from a master device and data in a bidirectional communication of the master device and a slave device. 
       FIG. 7A  shows an example of a configuration of a device address. The device address is configured by high-order 7 bits. When a low-order 1 bit is 0, this indicates writing, and when the low-order 1 bit is 1, this indicates reading. 
       FIG. 7B  is a schematic diagram of timing of the two lines. As shown in an upper side, when a level value of a signal of the data line is LOW, it becomes a Start state such that the data is sent from the high-order bits. When a level value of a signal of the data lien is HIGH, it becomes a Stop state. The timing of a corresponding clock line is shown in a lower side.  FIG. 7B  shows an example of a one bite transfer. When the data and ACK are repeated a plurality of times until the Stop state, a first byte is a slave address, however, remaining bytes can be set to contents of a communication. 
     (Second Embodiment) 
     A second embodiment of the present invention will be described below by referring to  FIG. 8 . The second embodiment is an extension of the first embodiment, so that an explanation common to both the embodiments will be omitted. A method for solving a problem includes following two items. The two items will be described below by referring to a sequence shown in  FIG. 8 .
     (1) When a power source of a PC system is turned ON in a docking state, the Peakshift application transmits Peakshift start and end times to the EC via a BIOS. The BIOS calculates a time from a present time based on the information received from the application and sets a time up to that time to the 1st EC. The 1st EC transmits the received information to the 2nd EC. The 1st EC and the 2nd EC start timers and respectively count down.   (2) Under a docking state, in a Peakshift control period which starts from the Peakshift start time Ps, the 2nd battery driving is executed. When there is no remaining capacity of the 2nd battery, one of the following three cases are selected and continuously used until the Peakshift end time Pe. That is, when it becomes the Peakshift start time Ps, an AC driving is switched to the 2nd battery driving under both the states where the power source is turned ON and OFF (the batteries are prohibited from being charged).
 
&lt;Method 1 ( FIG. 8( a ) ): A charged capacity of the battery of the Tablet side is retained and the EC switches to the AC driving&gt;
   

     When the remaining capacity of the 2nd battery is insufficient (Low) (timing T 21 ), the 2nd battery driving is switched to the AC driving. 
     &lt;Method 2 ( FIG. 8( b ) ): the EC is set to a Tablet battery driving until a remaining capacity of a Tablet side battery reaches a reference value (for instance, the remaining capacity is 30%), and then, the EC changes to the AC driving&gt; 
     When the remaining capacity of the 2nd battery becomes insufficient (Low)(timing T 21 ), the 2nd battery driving is switched to the Tablet battery driving. When the remaining capacity of the Tablet side battery lowers to the reference value, The Tablet battery driving is switched to the AC driving. 
     &lt;Method 3 ( FIG. 8( c ) ): When a battery state of the Tablet side battery is Low (a remaining capacity is 5%), the EC switches the AC driving from the battery driving&gt; 
     When the remaining capacity of the 2nd battery is insufficient (Low)(timing T 21 ), the 2nd battery driving is switched to the Tablet battery driving. When the remaining capacity of the Tablet side battery is becomes insufficient (Low, for instance 5%), the Tablet battery driving is switched to the AC driving. 
     As described above, since the KB Dock side battery and the 2nd EC/KBC are mounted, the Peakshift control can be executed even in the undock state. Thus, in the time period in which the power consumption is high, the supply of the electric power from the AC adapter can be stopped such that the power consumption can be suppressed by switching the AC driving to the battery driving. 
     During the Docking state, in the Tablet side, the setting information of the Peakshift is reported to the 2nd EC/KBC via the 1st EC/KBC. Accordingly, under a state that the Docking state is released, the Peakshift control can be executed also in the KB side. 
     Further, in the docking state, during the Peakshift control period, the 2nd battery driving is executed. When there is no remaining capacity of the 2nd battery, one of the following three cases may be selected and continuously used.
     (A) The charged capacity of the Tablet side battery is retained to switch the 2nd battery driving to the AC driving.   (B) The Tablet battery driving is executed by the Tablet battery until the remaining capacity of the Tablet side battery reaches the reference value (the remaining capacity is 30%), and then, the Tablet battery driving is switched to the AC driving.   (C) The battery state of the Table side battery becomes Low (the remaining capacity is 5%), the Tablet battery driving is switched to the AC driving.   

     In the embodiment, under the states of (A) to (C), the driving is executed under a power saving (the Peakshift) mode and both the batteries are not charged. 
     The present invention is not limited to the above-described embodiments and may be additionally modified in various ways and embodied within a scope that does not deviate from the gist of the present invention. 
     Further, when the plurality of component elements disclosed in the above-described embodiments are suitably combined together, various inventions may be devised. For instance, some component elements may be deleted from all the component elements disclosed in the embodiments. Further, the component elements of the different embodiments may be suitably combined together.