Patent Publication Number: US-9841796-B2

Title: Preventing dark current in battery management system

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application claims the benefit under 35 USC 119(a) of Korean Patent Application No. 10-2014-0173009 filed on Dec. 4, 2014, in the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes. 
     BACKGROUND 
     1. Field 
     The following description relates to techniques, methods, and apparatuses to prevent dark current in a battery management system (BMS). 
     2. Description of Related Art 
     As environmental concerns and energy resource issues become more important, electric powered vehicles have been touted as the vehicles of the future. The main power source of an electric power vehicle includes a battery formed in a single pack with a plurality of rechargeable and dischargeable secondary cells. As a result of using electricity to power the vehicle, the electric vehicle does not emit exhaust gas and produces less noise. 
     Recently, research is being conducted to increase battery life and control of a battery using a battery control apparatus. In addition, research is also being conducted regarding the stability of the battery and the battery control apparatus. 
     SUMMARY 
     This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
     In one general aspect, a battery control apparatus includes: a processor; a voltage regulator including an input and an output, the voltage regulator configured to receive power supplied from a power supply at the input, regulate the voltage of the power, and provided the regulated voltage to the output to power the processor; a first switch having a first state connecting the input of the voltage regulator to receive the power from the power supply and a second state disconnecting the input of the voltage regulator from the power supply to cut off the power from the input to the voltage regulator; and a second switch having an output connected to the first switch, the second switch configured to provide a control signal to the output to place the first switch in the one of the first state or the second state. 
     The first switch may include: a transistor connected to the second switch, the transistor being located between the power supply and the voltage regulator; and a resistor connected in parallel to the transistor. 
     The second switch may include an input configured to receive a power latch signal from the processor and a driving signal from the power supply and to output the control signal to place the first switch in the first state in response to receiving at least one of the driving signal and the power latch signal. The second switch may be configured to stop output of the control signal and place the first switch in the second state once a predetermined period of time elapses after the second switch ceases to receive the driving signal. The processor may be configured to transmit the power latch signal to the second switch when the driving signal is not input to the processor for a period of time, the period of time being from a point in time when the driving power is provided to the processor to a point in time when the predetermined period of time elapses. The processor also may be configured to stop transmitting the power latch signal to the second switch, and the second switch is configured to place the first switch in the second state after the predetermined period of time elapses when the second switch stops receiving the driving signal and the power latch signal. 
     The processor may be configured to terminate a program being processed by the processor during the predetermined period of time. The processor also may be configured to set the predetermined period of time to be equal to or longer than a period of time required to terminate the program. 
     The second switch may include: an OR gate configured to transmit an output signal when receiving at least one of the driving signal and the power latch signal; and a transistor connected between the OR gate and the first switch, the transistor configured to place the first switch in the first state in response to the output signal provided from the OR gate. 
     The second switch may include: a first diode having an input and an output, the first diode configured transfer the driving signal received at the input of the first diode to the output of the first diode; a second diode having an input and an output, the second diode configured to transfer the power latch signal received at the input of the second diode to the output of the second diode; and a first transistor, connected to the output of the first diode and the output of the second diode, the first transistor configured to place the first switch in the first state and the second state, wherein the first transistor places the first switch in the second state when neither the driving signal is output from the first diode, nor the power latch signal is output from the second diode. 
     The second switch also may include a second transistor comprising an input configured to receive the driving signal and an output connected to the first diode, the second transistor configured to transfer the driving signal received at the input to the output. 
     The second switch may include: a transistor having an input, the transistor configured to receive a current at the input and place the first switch in the first state when the input receives the current and to place the first switch in the second state when the input stops receiving the current; and a capacitor configured to provide the current to the transistor for a predetermined period of time after the driving signal stops being transmitted to the second switch, wherein, the current provided to the transistor corresponds to the current provided by the driving signal. The capacitor may have a capacity enabling the capacitor to provide the current to the transistor for the predetermined period of time. The second switch also may include: a diode, connected between the transistor and the capacitor, configured to transfer the driving signal and the current from the capacitor to the transistor; and a resistor connected in parallel to the diode. 
     In another general aspect, a power management apparatus includes: a power providing unit configured to provide a driving power to a processor; and a power controller configured to control providing of the driving power by the power providing unit based on receiving an input of a driving signal to operate the processor. 
     The power providing unit may include a voltage regulator configured to regulate a voltage of the driving power input to the processor. 
     The power providing unit may be configured to provide the driving power to the processor in response to receiving at least one of an input of a power latch signal from the processor and the input of the driving signal. 
     The power controller may be configured to control the power providing unit to stop providing the driving power to the processor when a predetermined period of time elapses after the power controlling unit stops receiving input of the driving signal. The power controller also may be configured to receive an input of the power latch signal from the processor during the predetermined period of time after power controlling unit stops receiving input of the driving signal and control the power providing unit to stop providing the driving power to the processor when the input of the power latch signal is terminated. 
     The predetermined period of time may correspond to the time need by the processor to terminate a program being processed by the processor. 
     In another general aspect, a method of controlling a processor includes: receiving a driving power from a voltage regulator in response to a driving signal to operate the processor being input to a battery control apparatus comprising the processor; operating the processor using the received driving power; transmitting a power latch signal to a switch during a period from a point in time when the driving power is provided to the processor to a point in time when a predetermined period of time elapses after the input of the driving signal to the battery control apparatus is interrupted, the switch being configured to maintain a connection between a power supply and the voltage regulator in response to receiving at least one of the driving signal and the power latch signal; and interrupting transmission of the power latch signal to the switch in response to the predetermined period of time elapsing. 
     The method may further include preventing any power consumption by the processor in response to interruption of transmission of the power signal. 
     The method may further include: stop receiving the driving power from the voltage regulator to operate the processor from being input to a battery control apparatus comprising the processor; and stop operating the processor. 
     The method may further include terminating a program being processed by the processor during the predetermined period of time. The method also may further include setting the predetermined period of time to be equal to or longer than a period of time required to terminate the program. 
     Other features and aspects will be apparent from the following detailed description, the drawings, and the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram illustrating an example of a battery control apparatus. 
         FIG. 2  is a block diagram illustrating an example of a power management apparatus. 
         FIG. 3  is a block and circuit diagram illustrating an example of a battery control apparatus included in a battery system. 
         FIG. 4  illustrates an example of a timing chart based on the operation of the battery control apparatus of  FIG. 3 . 
         FIGS. 5, 6, 7, and 8  are block and circuit diagrams illustrating examples of a battery control apparatus included in a battery system. 
         FIG. 9  is a flowchart illustrating an example of a method of controlling a processor. 
     
    
    
     Throughout the drawings and the detailed description, the same reference numerals refer to the same elements. The drawings may not be to scale, and the relative size, proportions, and depiction of elements in the drawings may be exaggerated for clarity, illustration, and convenience. 
     DETAILED DESCRIPTION 
     The following detailed description is provided to assist the reader in gaining a comprehensive understanding of the methods, apparatuses, and/or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatuses, and/or systems described herein will be apparent to one of ordinary skill in the art. The sequences of operations described herein are merely examples, are not limited to those set forth herein, but may be changed as will be apparent to one of ordinary skill in the art, with the exception of operations necessarily occurring in a certain order. Also, descriptions of functions and constructions that are well known to one of ordinary skill in the art may be omitted for overall conciseness and clarity. 
     The features described herein may be embodied in different forms, and are not to be construed as being limited to the examples described herein. Rather, the examples described herein have been provided so that this disclosure is thorough and complete, and conveys the full scope of the disclosure to one of ordinary skill in the art. 
     Various alterations and modifications may be made to the exemplary embodiments, some of which are illustrated in detail in the drawings and detailed description. However, it should be understood that these embodiments are not construed as limited to the illustrated forms and include all changes, equivalents or alternatives within the knowledge and the technical scope of this disclosure. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “include” and/or “have,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with the context of the relevant art described herein and should not be interpreted in an idealized or overly formal sense, unless expressly so defined herein. 
     Hereinafter, exemplary embodiments are described in detail with reference to the accompanying drawings, wherein like reference numerals refer to like elements throughout. Therefore, redundant descriptions of like elements are omitted herein. Moreover, a detailed description of a related, known function or configuration may be omitted when it is determined that inclusion makes the description of the present invention unnecessarily cumbersome or ambiguous. 
       FIG. 1  is a block diagram illustrating an example of a battery control apparatus  100 . 
     Referring to  FIG. 1 , the battery control apparatus  100  includes a first switch  110 , a second switch  120 , a voltage regulator  130 , and a processor  140 . 
     The battery control apparatus  100  controls a battery (not shown). In this example, the battery supplies power to a vehicle that includes the battery. The vehicle may be, for example, an electric vehicle (EV) or an electric cycle. The battery may include a plurality of battery modules. The plurality of battery modules may each include a plurality of cells. In one example, the plurality of cells are secondary batteries, for example, lithium ion batteries. Capacities of the plurality of cells may be the same as or different from each other. 
     The battery control apparatus  100  monitors a state of the battery and controls the battery. In one example, the battery control apparatus  100  may be a battery management system (BMS). 
     The battery control apparatus  100  performs thermal control of the plurality of battery modules in the battery. Additionally, the battery control apparatus  100  prevents overcharging and over-discharging of the plurality of battery modules. The battery control apparatus  100  also controls the plurality of battery modules such that the charge state of each module are equal. Accordingly, the battery control apparatus  100  may increase the energy efficiency of the plurality of battery modules and prevent a reduction in the life of the plurality of battery modules. 
     Additionally, the battery control apparatus  100  may detect a state of health (SoH), a state of charge (SoC), a state of function (SoF), and other parameters of the battery. For example, the SoH indicates a degree of degradation in the performance of the battery as compared to the performance of the battery during manufacture, the SoC indicates information about an amount of charge accepted by the battery, and the SoF indicates information about a degree to which the performance of the battery matches a predetermined condition. 
     The battery control apparatus  100  may provide the SoH, the SoC, and the SoF to an electronic control unit (ECU) (not shown). The battery control apparatus  100  may communicate with the ECU using a controller area network (CAN) communication (not shown). 
     The processor  140  controls the battery control apparatus  100 . For example, the processor  140  controls the other units included in the battery control apparatus  100 . The processor  140  may be implemented using, for example, a microcontroller unit (MCU). 
     The processor  140  operates when a driving power is supplied to the processor  140 . When the driving power is absent, the processor  140  does not operate. For example, when an ignition switch of the vehicle is turned on, the driving power is supplied to the processor  140 . When the ignition switch is turned off, the driving power is not supplied to the processor  140 . 
     The voltage regulator  130  regulates a voltage of the driving power supplied by a power supply device to the processor  140 . The power supply device (not shown) may be an external power source (for example, a lead storage battery) to continuously supply a driving power to the battery control apparatus  100 . The power supply device also may be referred to as a “power supply.” The power supply device may be located outside the battery control apparatus  100 . 
     The voltage regulator  130  regulates the voltage of the driving power supplied from the power supply that is input to the processor  140 . As a result, the driving power is provided to the processor  140  at the regulated voltage. For example, a voltage of 0 volt (V) to 5 V may be input to the processor  140 . When the power supply supplies a driving power with a voltage greater than 5 V to the voltage regulator  130 , the voltage regulator  130  regulates the voltage of the driving power to be equal to or less than 5 V. Accordingly, the voltage regulator  130  may transmit a voltage equal to or less than 5 V to the processor  140  to prevent an overvoltage from being input to the processor  140 . 
     The first switch  110  switches a connection between the power supply and the voltage regulator  130  on and off in response to the control received from the second switch  120 . The first switch  110  is located between the power supply and the voltage regulator  130 . 
     The second switch  120  controls the first switch  110  based on an input of a driving signal to operate the processor  140 . For example, the driving signal may be received from the ignition switch. When the ignition switch is turned on, the driving signal is transmitted to the battery control apparatus  100 . When the ignition switch is turned off, the driving signal is not transmitted to the battery control apparatus  100 . 
     In an example, the first switch  110  and the second switch  120  may each include a transistor. For example, the first switch  110  may include a transistor connected to the second switch  120  and a resistor connected in parallel with the transistor. The transistor may be, for example, a bipolar junction transistor (BJT), a field effect transistor (FET), or an insulated gate bipolar mode transistor (IGBT). However, according to one example, the first switch  110  may be implemented using, but not limited to, any apparatus capable of switching on and off the connection between the power supply and the voltage regulator  130 , and the second switch  120  may be implemented using any apparatus capable of controlling the first switch  110  based on an input of a driving signal. 
     When a driving signal is received from the ignition switch, the second switch  120  turns on the first switch  110  to connect the power supply to the voltage regulator  130 . Accordingly, the voltage regulator  130  may supply the driving power from the power supply to the processor  140 . The processor  140  operates when the driving power is received. 
     When the driving signal is not received from the ignition switch, the second switch  120  turns off the first switch  110  to disconnect the power supply from the voltage regulator  130 . When the power supply is disconnected from the voltage regulator  130 , the driving power is not provided from the power supply to the battery control apparatus  100 . Typically, a dark current refers to the leakage of current flowing from a voltage regulator when a power supply is connected to the voltage regulator. A higher value of the dark current has a direct influence on a use period of a system with a limited power supply, such as a battery. However, according to the above-described implementation, a dark current is prevented from being generated in the battery control apparatus  100 . 
     Operation of the processor  140  may be interrupted when the power supply is disconnected from the voltage controller  130 . When operation of the processor  140  is unexpectedly terminated because the power supply is disconnected, performance of the processor  140  may be reduced or the processor  140  may be damaged, depending on circumstances. Thus, the second switch  120  turns off the first switch  110  to disconnect the power supply from the voltage regulator  130  after a predetermined period of time elapses, even though the driving signal is not received. During the predetermined period of time, the processor  140  may perform a series of operations allowing normal termination of operation of the processor  140 . Accordingly, operation of the processor  140  may be stably terminated even when providing of the driving power to the processor  140  is to be interrupted. 
     In an example, the operation, performed by the battery control apparatus  100 , to delay cutoff of the supply of driving power to the processor  140  for a predetermined period of time in order to terminate the processor  140  stably may be referred to as a “power latch.” 
     When a driving signal is not supplied to the second switch  120 , the second switch  120  controls the first switch  110  to remain in an ON state for a predetermined period of time and thereby perform a power latch. For example, the battery control apparatus  100  may include a capacitor configured to provide a current to the second switch  120  for a predetermined period of time corresponding to the current of the driving signal. In this example, when the capacitor provides the current to the second switch  120  for the predetermined period of time, and the first switch  110  remains in the ON state for the predetermined period of time. 
     The processor  140  may receive an input of the driving signal from the ignition switch. To perform the power latch, the processor  140  transmits a power latch signal to the second switch  120  during the period from a point in time when the driving power is input to the processor  140  to a point in time when a predetermined period of time elapses after the input of the driving signal to the processor  140  is interrupted. The power latch signal refers to a signal having a power corresponding to that of the driving signal. The second switch  120  maintains the first switch  110  in the ON state while the power latch signal is being received. The second switch  120  controls the first switch  110  to be in the OFF state when the power latch signal is no longer received. 
     For example, when no driving signal is input to the processor  140 , the processor  140  transmits a control signal to the second switch  120  to control the second switch  120  to turn off the first switch  110  after the predetermined period of time elapses and perform the power latch. The second switch  120  controls the first switch  110  to be in the OFF state in response to the control signal being received from the processor  140 . 
     During the predetermined period of time of the power latch, the processor  140  may terminate a program being processed by the processor  140 . In this example, the processor  140  may set the predetermined period of time to be equal to or longer than a period of time required to terminate the program properly. 
       FIG. 2  illustrates an example of a power management apparatus  200 . 
     As shown in  FIG. 2 , the power management apparatus  200  includes a power providing unit  210  and a power controller  220 . The power providing unit  210  provides a driving power to a processor configured to control a battery control apparatus. The processor may be, for example, the processor  140  of  FIG. 1 . The processor operates when the driving power is provided to the processor, and the processor ceases to operate when the driving power is not provided to the processor. The power management apparatus  200  may be included in the battery control apparatus or provided separately from the battery control apparatus. 
     The power providing unit  210  continuously receives a power supply from an external power source and provides the driving power to the processor. The power providing unit  210  may include a voltage regulator configured to regulate the voltage of the driving power that is input to the processor. The power providing unit  210  provides the driving power to the power providing unit  210  at the voltage regulated by the voltage regulator. The voltage regulator in the power providing unit  210  may be, for example, the voltage regulator  130  of  FIG. 1 . 
     The power controller  220  receives an input of a driving signal from an ignition switch to operate the processor. Based on the input of the driving signal, the power controller  220  controls providing of the driving power of the power providing unit  210 . 
     In an example, the power controller  220  includes a first switch and a second switch. The power controller  220  may be located between the external power source and the power providing unit  210 . The first switch switches the connection between the external power source and the power providing unit  210  on and off. The second switch controls the first switch based on an input of the driving signal. The first switch and the second switch may be, for example, the first switch  110  and the second switch  120  of  FIG. 1 , respectively. 
     To operate a driving vehicle including the power management apparatus  200 , a user sets an ignition switch of the driving vehicle to an ON state. In the ON state, the ignition switch transmits the driving signal to at least one of the power controller  220  and the processor. While the driving signal is being received, the power controller  220  controls the power providing unit  210  to provide the driving power to the processor. 
     When the ignition switch is turned off, transmission of the driving signal to at least one of the power controller  220  and the processor is interrupted. When the driving signal is not received, the power controller  220  controls the power providing unit  210  to cease providing the driving power to the processor. Because the driving power input to the processor is cut off, no current exists between the processor and the power providing unit  210 . Accordingly, a dark current is not generated in the battery control apparatus that includes the processor. 
     The processor could improperly terminate an operation if the power supplied to the processor is cut off by the power providing unit  210  immediately after the ignition switch is turned off. As a result of the immediate loss of power, the performance of the processor may be reduced, or the processor may be damaged or destroyed. To prevent this degradation in the performance of the processor, the power management apparatus  200  performs the power latch. 
     In an example, the processor may receive input of a driving signal from the ignition switch. To perform a power latch, the processor transmits a power latch signal to the power controller  220  during a period from a point in time when the driving power is input to the processor to a point in time when a predetermined period of time elapses after the input of the driving signal to the processor is interrupted. When the power latch signal is received, the power controller  220  controls the power providing unit  210  to provide the driving power to the processor even though the driving signal is no longer received. During the period from a point in time when the input of the driving signal is interrupted to a point in time while the processor transmits the power latch signal, the processor may terminate a program being processed by the processor. 
     In another example, when a predetermined period of time elapses after interruption of the input of the driving signal, the power controller  220  controls the power providing unit  210  to stop providing the driving power to the processor regardless of receiving the power latch signal. For example, the power management apparatus  200  may include a capacitor configured to provide power corresponding to the driving signal. When the driving signal is not input to the power controller  220 , the capacitor provides power corresponding to the driving signal for a predetermined period of time. Accordingly, the power controller  220  controls the power providing unit  210  to provide the driving power to the processor during the predetermined period of time. When the predetermined period of time elapses, the power controller  220  controls the power providing unit  210  to stop providing the driving power to the processor. 
       FIG. 3  illustrates an example of a battery control apparatus included in battery system  300 . 
     As shown in  FIG. 3 , the battery system  300  includes a battery (not shown), a power supply  310 , a battery control apparatus  320 , and an ignition switch  370 . The power supply  310  may be, for example, an external power source that continuously supplies a driving power to the battery control apparatus  320 . In an example, the power supply  310  may provide a direct current (DC) power to the battery control apparatus  320 . In another example, the power supply  310  may include an alternating current (AC)-to-DC (AC/DC) converter. In this example, the power supply  310  receives AC power from an external apparatus (not shown), converts the AC power to a DC power using the AC/DC converter, and provides the DC power to the battery control apparatus  320 . 
     The ignition switch  370  is turned on and off to control ignition of a vehicle including the battery system  300 . When the ignition switch  370  is in an ON state, the ignition is turned on. When the ignition switch  370  is in an OFF state, the ignition is turned off. The ignition switch  370  may be controlled based on an input from the external apparatus. In an example, when the external apparatus places the ignition switch  370  in the ON state, the ignition switch  370  transmits a driving signal to an OR gate  351  and an MCU  340 . In another example, when the external apparatus places the ignition switch  370  in the OFF state, the ignition switch  370  does not transmit the driving signal to the OR gate  351  and the MCU  340 . 
     The battery control apparatus  320  includes an FET  321 , a resistor  322 , a regulator  330 , the MCU  340 , the OR gate  351 , and a BJT  352 . 
     The FET  321  switches a connection between the power supply  310  and the regulator  330  on and off. The FET  321  may be, for example, one of a complementary metal-oxide-semiconductor (CMOS) transistor, an N-channel metal-oxide-semiconductor (NMOS) transistor and a P-channel metal-oxide-semiconductor (PMOS) transistor. 
     The BJT  352  is connected between the OR gate  351  and the FET  321  and controls a switching operation of the FET  321 . In  FIG. 3 , the FET  321  and the BJT  352  are an NMOS transistor and an NPN transistor, respectively; however, the FET  321  and the BJT  352  are not limited thereto. 
     In an example, when the external apparatus places the ignition switch  370  in the ON state, the ignition switch  370  transmits the driving signal to the OR gate  351  and the MCU  340 . In response to receiving the driving signal, the OR gate  351  outputs a signal to the base of the BJT  352 . When the output signal is input to the base of the BJT  352 , the BJT  352  is turned on, and the potential of the collector of the BJT  352  is equal to that of a ground. The gate of the FET  321  also has a potential equal to that of ground and; accordingly, a voltage is applied to the resistor  322 . In this example, a source-gate voltage of the FET  321  becomes higher than the threshold voltage of the FET  321  and; accordingly, the FET  321  is turned on. When the FET  321  is turned on the power supply  310  is connected to the regulator  330 . 
     When the power supply  310  and the regulator  330  are connected to each other, the regulator  330  receives power from the power supply  310 . The regulator  330  may regulate a voltage of the power received from the power supply  310  that is input to the MCU  340 , and the regulator  330  provides power at the regulated voltage to the MCU  340 . The MCU  340  operates using the power received from the regulator  330 . Additionally, the MCU  340  may receive the driving signal from the ignition switch  370 . While the driving signal is being received, the MCU  340  transmits a power latch signal to the OR gate  351 . The power latch signal is transmitted to perform a power latch having a power corresponding to the driving signal. While the OR gate  351  receives the power latch signal from the MCU  340  and the driving signal from the ignition switch  370 , the OR gate  351  continuously transmits the output signal to the base of the BJT  352 . 
     In another example, when the external apparatus places the ignition switch  370  in the OFF state, the ignition switch  370  stops transmitting the driving signal to the OR gate  351  and the MCU  340 . Even though the driving signal is not received, the OR gate  351  continues to output a signal to the base of the BJT  352  because the power latch signal is received by the BJT  352  from the MCU  340 . 
     When the driving signal is not received from the ignition switch  370 , the MCU  340  may terminate a program being processed during a predetermined period of time. The predetermined period of time may be set in advance, or the MCU  340  may set the predetermined period of time as the period of time from a point in time when a reception of the driving signal is interrupted to a point in time when all programs are terminated. 
     When the predetermined period of time elapses, or when all programs processed by the MCU  340  are terminated, the MCU  340  stop transmitting the power latch signal to the OR gate  351 . When both the driving signal and the power latch signal are not received by the OR gate  351 , the OR gate  351  stops outputting a signal to the base of the BJT  352 . In response to no output signal at the base of the BJT  352 , the BJT  352  is turned off (or cut off). The collector of the BJT  352  is disconnected from the emitter of the BJT  352  and; accordingly, has a potential equal to that of the power supply  310 . Also, the source and the gate of the FET  321  each have a potential equal to that of the power supply  310 . In other words, there is no difference in potential between the source and the gate of the FET  321 . The FET  321  may be turned off to disconnect the power supply  310  from the regulator  330 . Accordingly, the power supplied by the power supply  310  is transferred to ground GND through the resistor  322  and the BJT  352 . Additionally, current is blocked from flowing between the regulator  330  and the MCU  340 ; thus, dark current is prevented from being generated in the battery control apparatus  320 . 
       FIG. 4  illustrates an example of a time chart based on an operation of the battery control apparatus  320  of  FIG. 3 . 
     In the time chart shown in  FIG. 4 , the horizontal axis represents time, and the vertical axis represents whether an operation is performed (or whether a signal exists). 
     The power supply  310  continuously supplies power to the battery control apparatus  320  from a point in time  411 . 
     The ignition switch  370  is in the ON state during the period from a point in time  421  to another point in time  422 . The ignition switch is in the OFF state from the point in time  422  onward. 
     In the ON state, the ignition switch  370  transmits a driving signal to the OR gate  351  and the MCU  340 . In response to the driving signal being received by the OR gate  351 , the OR gate  351  transmits the output signal to the base of the BJT  352 . In response to the output signal being received at the base of the BJT  352 , the BJT  352  is turned on at the point in time  431  and causes the FET  321  to be placed in the ON state. The FET  321  is turned on by the BJT  352  at the point in time  441  connecting the power supply  310  to the regulator  330 . The power supply  310  transmits power to the regulator  330  starting at the point in time  451 . The regulator  330  regulates the voltage of the power received from the power supply  310  that is input to the MCU  340  and provides the power to the MCU  340  at the regulated voltage. The MCU  340  is operated at the point in time  461  the power from the regulator  330  is received. To perform a power latch, the MCU  340  transmits a power latch signal to the OR gate  351 . 
     At the point in time  422 , the ignition switch  370  is turned off and ceases to transmit the driving signal to the OR gate  351  and the MCU  340 . In response to interruption of the of the driving signal at the point in time  422 , the MCU  340  terminates a program being processed by the MCU  340  during the period from the point in time  481  to another point in time  482 . The MCU  340  performs a process to terminate the program during the period from the point in time  481  to the point in time  482 ; accordingly, performance of the MCU  340  is maintained even though power is not supplied to the MCU  340 . When the program is terminated, the MCU  340  ceases to transmit the power latch signal to the OR gate  351 . In response to neither the driving signal nor the power latch signal being received, the OR gate  351  stops transmitting the output signal to the base of the BJT  352 ; accordingly, the BJT  352  is turned off at the point in time  432 . When the BJT  352  is turned off, the FET  321  is turned off at the point in time  442 , and the power supply  310  is disconnected from the regulator  330 . The regulator  330  interrupts the supply of power to the MCU  340  at the point in time  452 , and the MCU  340  interrupts the operation of the MCU  340  at the point in time  462 . Accordingly, current does not flow between the regulator  330  and the MCU  340 , and dark current is prevented from being generated in the battery control apparatus  320 . 
       FIGS. 5 through 8  illustrate examples of a battery control apparatus that may be included in battery systems. 
     As shown in  FIG. 5 , a battery system  500  includes a battery (not shown), a power supply  510 , a battery control apparatus  520 , and an ignition switch  570 . The power supply  510  may be, for example, an external power source to continuously to supply a driving power (for example, a DC power) to the battery control apparatus  520 . 
     The ignition switch  570  is turned on and off to control an ignition of a vehicle including the battery system  500 . In an example, when the ignition switch  570  is in an ON state, the ignition is turned on, and the ignition switch  570  transmits a driving signal to a first diode  551  and an MCU  540 . In another example, when the ignition switch  570  is in an OFF state, the ignition is turned off, and the ignition switch  570  does not transmit the driving signal to the first diode  551  and the MCU  540 . 
     The battery control apparatus  520  includes an FET  521 , a resistor  522 , a regulator  530 , the MCU  540 , the first diode  551 , a second diode  552 , and a BJT  553 . 
     The FET  521  switches a connection between the power supply  510  and the regulator  530  on and off. 
     The BJT  553  controls a switching operation of the FET  521 . As shown in  FIG. 5 , the FET  521  and the BJT  553  are an NMOS transistor and an NPN transistor, respectively; however, the FET  521  and the BJT  553  are not limited thereto. 
     The first diode  551  receives an input of the driving signal from the ignition switch  570  and transfers the driving signal to the BJT  553 . The second diode  552  receives an input of a power latch signal from the MCU  540  and transfers the power latch signal to the BJT  553 . The first diode  551  and the second diode  552  may correspond to, for example, the OR gate  351  shown in  FIG. 3 . In  FIG. 5 , the first diode  551  and the second diode  552  are rectification diodes; however, the first diode  551  and the second diode  552  are not limited thereto. For example, the first diode  551  and the second diode  552  may be a Zener diode, a variable capacitance diode, a voltage variable resistor diode, a switching diode, a Schottky barrier diode, a band switching diode, a tunnel diode, an impact avalanche transit-time (IMPATT) diode, a Gunn diode, and a PIN diode. 
     In an example, when an external apparatus controls the ignition switch  570  to be in the on state, the ignition switch  570  transmits the driving signal to the first diode  551  and the MCU  540 . In response to the driving signal being received, the first diode  551  outputs the driving signal to the base of the BJT  553 . When the driving signal is input to the base of the BJT  553 , the BJT  553  is turned on and the potential of the collector of the BJT  553  equals ground. The potential of the gate of the FET  521  also equals ground; accordingly, a voltage is applied to the resistor  522 . As the source-gate voltage of the FET  521  becomes higher than the threshold voltage of the FET  521 ; accordingly, the FET  521  is turned on and connects the power supply  510  to the regulator  530 . When the power supply  510  and the regulator  530  are connected to each other, the regulator  530  receives power from the power supply  510 . The regulator  530  regulates the voltage of the power received from the power supply  510  that is input to the MCU  540 , and the regulator  530  provides power with a regulated voltage to the MCU  540 . The MCU  540  operates using the power received from the regulator  530 . Additionally, the MCU  540  receives the driving signal from the ignition switch  570 . While the driving signal is received, the MCU  540  transmits the power latch signal to the second diode  552 , and the second diode  552  transfers the power latch signal to the BJT  553 . 
     In another example, when the external apparatus controls the ignition switch  570  to be in the OFF state, the ignition switch  570  stops transmitting the driving signal to the first diode  551  and the MCU  540 . When the first diode  551  ceases to transfer the driving signal to the BJT  553 , the BJT  553  still receives the power latch signal from the second diode  552 . Accordingly, a predetermined voltage continues to be generated at the collector of the BJT  553 , and the FET  521  remains in the on state. 
     When the driving signal is not received from the ignition switch  570 , the MCU  540  terminates a program being processed within a predetermined period of time. When the predetermined period of time elapses, or when all programs processed by the MCU  540  are terminated, the MCU  540  stops transmitting the power latch signal to the second diode  552 , and the second diode  552  ceases to transfer the power latch signal to the BJT  553 . Because the second diode  552  does not transfer the power latch signal, the driving signal and the power latch signal are not input to the base of the BJT  553 . As a result, the base of the BJT  553  is turned off, and the BJT  553  also is turned off. The collector of the BJT  553  is disconnected from the emitter of the BJT  553 ; accordingly, the potential of the collector is equal to that of the power supply  510 . Also, the source and the gate of the FET  521  each have a potential equal to that of the power supply  510 . In other words, there is no difference in the potential between the source and the gate of the FET  521 . The FET  521  is turned off to disconnect the power supply  510  from the regulator  530 . Accordingly, the power supplied by the power supply  510  is transferred to ground GND through the resistor  522  and the BJT  553 . Additionally, current is prevented from flowing between the regulator  530  and the MCU  540 ; thus, no dark current is generated in the battery control apparatus  520 . 
     Referring to  FIG. 6 , a battery system  600  includes a battery, a power supply  610 , a battery control apparatus  620 , and an ignition switch  670 . The power supply  610  may be, for example, an external power source to continuously supply a driving power (for example, a DC power) to the battery control apparatus  620 . 
     The ignition switch  670  is turned on and off to control an ignition of a vehicle including the battery system  600 . In an example, when the ignition switch  670  is in an ON state, the ignition may be turned on, and the ignition switch  670  transmits a driving signal to a first BJT  651  and an MCU  640 . In another example, when the ignition switch  670  is in an OFF state, the ignition may be turned off, and the ignition switch  670  does not transmit the driving signal to the first BJT  651  and the MCU  640   
     The battery control apparatus  620  includes an FET  621 , a first resistor  622 , a regulator  630 , the MCU  640 , the first BJT  651 , a second resistor  652 , a first diode  653 , a second diode  654 , and a second BJT  655 . 
     The FET  621  switches a connection between the power supply power supply  610  and the regulator  630  on and off. 
     The driving signal from the ignition switch  670  is input to the first BJT  651 , and the first BJT  651  transfers the driving signal to the first diode  653 . 
     The second BJT  655  controls a switching operation of the FET  621 . As shown in  FIG. 6 , the FET  621  is an NMOS transistor, and the first BJT  651  and the second BJT  655  are NPN transistors; however, the FET  621 , the first BJT  651 , and the second BJT  655  are not limited thereto. 
     The first diode  653  receives an input of the driving signal from the first BJT  651  and transfers the driving signal to the second BJT  655 . The second diode  654  receives an input of a power latch signal from the MCU  640  and transfers the power latch signal to the second BJT  655 . The first diode  653  and the second diode  654  may correspond to, for example, the OR gate  351  of  FIG. 3 . As shown in  FIG. 6 , the first diode  653  and the second diode  654  are rectification diodes; however, the first diode  653  and the second diode  654  are not limited thereto. 
     In an example, when an external apparatus controls the ignition switch  670  to be in the ON state, the ignition switch  670  transmits the driving signal to the first BJT  651  and the MCU  640 . 
     The first BJT  651  is turned on in response to the driving signal being received at the base of the first BJT  651 , and the first BJT  651  outputs a current corresponding to the driving signal to the emitter of the first BJT  651 . The current is transmitted from the emitter to the first diode  653 , and the first diode  653  transfers the current to the second BJT  655 . 
     While the current is input to the base of the second BJT  655 , the second BJT  655  is turned on, and the potential of the collector of the second BJT  655  is equal to that of ground. Also, the potential of the gate of the FET  621  equals that of the ground; accordingly, a voltage is applied to the first resistor  622 . As the source-gate voltage of the FET  621  becomes higher than the threshold voltage of the FET  621 ; accordingly, the FET  621  is turned on connecting the power supply  610  to the regulator  630 . 
     When the power supply  610  and the regulator  630  are connected to each other, the regulator  630  receives power from the power supply  610 . The regulator  630  regulates the voltage of the power received from the power supply  610  that is input to the MCU  640 . The regulator  630  provides the power with the regulated voltage to the MCU  640 . The MCU  640  operates using the power received from the regulator  630 . Additionally, the MCU  640  receives the driving signal from the ignition switch  670 . While the driving signal is being received, the MCU  640  transmits the power latch signal to the second diode  654 , and the second diode  654  transfers the power latch signal to the second BJT  655 . 
     In another example, when the external apparatus controls the ignition switch  670  to be in the OFF state, the ignition switch  670  ceases to transmit the driving signal to the first BJT  651  and the MCU  640 . The first BJT  651  may be turned off (or cut off) with no current output from the emitter of the first BJT  651  in response to the loss of input of the driving signal at the base of the first BJT  651 . The first diode  653  stops transmitting the current to the second BJT  655  in response to the lack of current being received from the emitter of the first BJT  651 . However, the second BJT  655  continues to receive the power latch signal from the second diode  654 . Accordingly, a predetermined voltage continues to be generated at the collector of the second BJT  655 , and the FET  621  remains in the on state. 
     When the driving signal is not received from the ignition switch  670 , the MCU  640  terminates a program being processed by the MCU  640  within a predetermined period of time. When the predetermined period of time elapses, or when all programs processed by the MCU  640  are terminated, the MCU  640  stops transmitting the power latch signal to the second diode  654 , and the power latch signal is not transferred from the second diode  654  to the second BJT  655 . Because the second diode  654  does not transfer the power latch signal, the driving signal and the power latch signal are not input to the base of the second BJT  655 . As a result, the base of the second BJT  655  is turned off, and the second BJT  655  also is turned off. The collector of the second BJT  655  is disconnected from the emitter of the second BJT  655 ; accordingly, the potential of the collector is equal to that of the power supply  610 . Also, the source and the gate of the FET  621  each have a potential equal to that of the power supply  610 . In other words, there is no difference in the potential between the source and the gate of the FET  621 . The FET  621  is turned off disconnecting the power supply  610  from the regulator  630 . Accordingly, the power supplied by the power supply  610  is transferred to a ground GND through the first resistor  622  and the second BJT  655 . Additionally, current is prevented from flowing between the regulator  630  and the MCU  640 ; thus, no dark current is generated in the battery control apparatus  620 . 
     As shown in  FIG. 7 , a battery system  700  includes a battery (not shown), a power supply  710 , a battery control apparatus  720 , and an ignition switch  770 . The power supply  710  may be, for example, an external power source to continuously supply a driving power (for example, a DC power) to the battery control apparatus  720 . 
     The ignition switch  770  is turned on and off to control the ignition of a vehicle including the battery system  700 . In an example, when the ignition switch  770  is in an ON state, the ignition may be turned on, and the ignition switch  770  transmits a driving signal to a BJT  752  and an MCU  740 . In another example, when the ignition switch  770  is in an OFF state, the ignition may be turned off, and the ignition switch  770  does not transmit the driving signal to the BJT  752  and the MCU  740 . 
     The battery control apparatus  720  includes an FET  721 , a resistor  722 , a regulator  730 , the MCU  740 , a capacitor  751 , and the BJT  752 . 
     The FET  721  switches a connection between the power supply  710  and the regulator  730  on and off. 
     The BJT  752  controls a switching operation of the FET  721 . As shown in  FIG. 7 , the FET  721  and the BJT  752  are an NMOS transistor and an NPN transistor, respectively: however, the FET  721  and the BJT  752  are not limited thereto. 
     In an example, when an external apparatus controls the ignition switch  770  to be in the ON state, the ignition switch  770  transmits the driving signal to the BJT  752  and the MCU  740 . The BJT  752  is turned on in response to the driving signal being input to the base of the BJT  752 , and the potential of the collector of the BJT  752  is equal to that of ground. Also, the potential of the gate of the FET  721  is equal to that of the ground; accordingly, a voltage is applied to the resistor  722 . When the source-gate voltage of the FET  721  becomes higher than the threshold voltage of the FET  721 , the FET  721  is turned on connecting the power supply  710  to the regulator  730 . 
     When the power supply  710  and the regulator  730  are connected to each other, the regulator  730  receives power from the power supply  710 . The regulator  730  regulates the voltage of the power received from the power supply  710  that is input to the MCU  740 , and the regulator  730  provides the power with the regulated voltage to the MCU  740 . The MCU  740  operates using the power received from the regulator  730 . Additionally, the MCU  740  receives the driving signal from the ignition switch  770 . 
     In another example, when the external apparatus controls the ignition switch  770  to be in the OFF state, the ignition switch  770  stops transmitting the driving signal to the BJT  752  and the MCU  740 . In this example, although the driving signal is not input to the emitter of the BJT  752 , the capacitor  751  transmits a current corresponding to the driving signal to the emitter of the BJT  752  for a predetermined period of time. The capacitor  751  may have a capacity enabling the transmission of the current corresponding to the driving signal for the predetermined period of time. Accordingly, a predetermined voltage continues to be generated at the collector of the BJT  752 , and the FET  721  remains in the ON state. The predetermined period of time is set in advance. For example, an average period of time required for a processing of the MCU  740  may be calculated in advance, and the capacitor  751  stores power corresponding to the calculated period of time. 
     When the driving signal ceases to be received from the ignition switch  770 , the MCU  740  may terminate a program being processed by the MCU  740  within the predetermined period of time. 
     When the predetermined period of time elapses, the capacitor  751  stops transferring current corresponding to the driving signal to the BJT  752 . The base of the BJT  752  is turned off in response to the lack of current input to the BJT  752 , and the BJT  752  is turned off. The collector of the BJT  752  is disconnected from the emitter of the BJT  752 ; accordingly, the potential of the collector of the BJT  752  is equal to that of the power supply  710 . Also, the potential of the source and the gate of the FET  721  are each equal to that of the power supply  710 . In other words, there is no difference in potential between the source and the gate of the FET  721 . The FET  721  is turned off disconnecting the power supply  710  from the regulator  730 . Accordingly, the power supplied by the power supply  710  is transferred to a ground GND through the resistor  722  and the BJT  752 . Additionally, current is prevented from flowing between the regulator  730  and the MCU  740 ; thus, no dark current is generated in the battery control apparatus  720 . 
     As shown in  FIG. 8 , a battery system  800  includes a battery (not shown), a power supply  810 , a battery control apparatus  820 , and an ignition switch  870 . The power supply  810  may be, for example, an external power source to continuously supply a driving power (for example, a DC power) to the battery control apparatus  820 . 
     The ignition switch  870  is turned on and off to control an ignition of a vehicle including the battery system  800 . In an example, when the ignition switch  870  is in an ON state, the ignition may be turned on, and the ignition switch  870  transmits a driving signal to a BJT  854  and an MCU  840 . In another example, when the ignition switch  870  is in an OFF state, the ignition may be turned off, and the ignition switch  870  does not transmit the driving signal to the BJT  854  and the MCU  840 . 
     The battery control apparatus  820  includes an FET  821 , a first resistor  822 , a regulator  830 , the MCU  840 , a capacitor  851 , a diode  852 , a second resistor  853 , and the BJT  854 . 
     The FET  821  switches a connection between the power supply  810  and the regulator  830  on and off. 
     The BJT  854  controls a switching operation of the FET  821 . As shown in  FIG. 8 , the FET  821  and the BJT  854  are an NMOS transistor and an NPN transistor, respectively, however, the FET  821  and the BJT  854  are not limited thereto. 
     The diode  852  is connected between the BJT  854  and the capacitor  851 . The diode  852  transfers the driving signal or a current, corresponding to the driving signal, to the BJT  854 . The second resistor  853  is connected in parallel to the diode  852 . 
     In an example, when an external apparatus controls the ignition switch  870  to be in the ON state, the ignition switch  870  transmits the driving signal to the diode  852  and the MCU  840 . The driving signal is input to the diode  852 , and the diode  852  transfers the driving signal to the base of the BJT  854 . The BJT  854  is turned on in response to the driving signal being received at the base of the BJT  854 , and the potential at the collector of the BJT  854  equals ground. Also, the potential of the gate of the FET  821  equals that of the ground; accordingly, a voltage is applied to the first resistor  822 . When the source-gate voltage of the FET  821  becomes higher than the threshold voltage of the FET  821 , the FET  821  is turned on connecting the power supply  810  to the regulator  830 . 
     When the power supply  810  and the regulator  830  are connected to each other, the regulator  830  receives power from the power supply  810 . The regulator  830  regulates the voltage of the power received from the power supply  810  that is input to the MCU  840 . The regulator  830  provides power with the regulated voltage to the MCU  840 . The MCU  840  operates using the power received from the regulator  830 . Additionally, the MCU  840  receives the driving signal from the ignition switch  870 . 
     In another example, when the external apparatus controls the ignition switch  870  to be in the OFF state, the ignition switch  870  cease to transmit the driving signal to the diode  852  and the MCU  840 , and the diode  852  ceases to transfer the driving signal to the BJT  854 . In this example, the capacitor  851  may transmit a current corresponding to the driving signal to the diode  852  for a predetermined period of time, and the diode  852  transfers the received current to the base of the BJT  854 . Accordingly, a predetermined voltage may continue to be generated at the collector of the BJT  854  allowing the FET  821  to remain in the ON state. The predetermined period of time is set in advance. 
     When the driving signal is not received from the ignition switch  870 , the MCU  840  may terminate a program being processed by the MCU  840  during a predetermined period of time. When the predetermined period of time elapses, the capacitor  851  stops transferring the current to the diode  852 , and the diode  852  does not input any current to the BJT  854 . The base of the BJT  854  is turned off in response to the lack of current being input to the BJT  854 . The collector of the BJT  854  is disconnected from the emitter of the BJT  854 ; accordingly, the potential of the collector equals that of the power supply  810 . Also, the potential of the source and the gate of the FET  821  are equal to that of the power supply  810 . In other words, there is no difference in potential between the source and the gate of the FET  821 . The FET  821  is turned off disconnecting the power supply  810  from the regulator  830 . Accordingly, the power supplied by the power supply  810  is transferred to a ground GND through the first resistor  822  and the BJT  854 . Additionally, current is prevented from flowing between the regulator  830  and the MCU  840 ; thus, no dark current is generated in the battery control apparatus  820 . 
       FIG. 9  illustrates an example of a method of controlling a processor. 
     Referring to  FIG. 9 , in operation  910 , the processor receives a driving power from a voltage regulator in response to a driving signal to operate the processor being input to a battery control apparatus including the processor. 
     In operation  920 , the processor is operated using the received driving power. 
     In operation  930 , the processor transmits a power latch signal to a switch during a period from a point in time when the driving power is provided to the processor to a point in time when a predetermined period of time elapses after an input of the driving signal to the battery control apparatus is interrupted. The switch is configured to switch a connection between a power supply and the voltage regulator on and off. 
     In an example, the processor receives an input of a driving signal and operates while the input of the driving signal is being received. The processor transmits a power latch signal to the switch during a period from a point in time when the processor starts to operate to a point in time when a predetermined period of time elapses after an input of the driving signal to the battery control apparatus is interrupted. While at least one of the driving signal and the power latch signal is being received, the switch connects the power supply to the voltage regulator. 
     When the input of the driving signal to the battery control apparatus is interrupted, the switch does receive the input of the driving signal but receives the power latch signal from the processor for the predetermined period of time. In response to the power latch signal being received, the switch continues to connect the power supply to the voltage regulator. 
     The processor may terminate a program being processed by the processor during the predetermined period of time. Accordingly, the processor is stably terminated preventing performance of the processor from being degraded. Additionally, the processor may set the predetermined period of time to be equal to or longer than a period of time required to terminate the program. In addition, the predetermined period of time may be set in advance. 
     In operation  940 , the processor interrupts the transmission of the power latch signal to the switch when the predetermined period of time elapses. When the power latch signal ceases to be input to the switch, the switch cuts the connection between the power supply and the voltage regulator, and the processor ceases to receive the driving power from the voltage regulator. As a result, operation of the processor is terminated. 
     In another example, when the driving signal ceases to be input to the processor, the processor transmits a control signal to the switch. The control signal causes the switch to cut the connection between the power supply and the voltage regulator after the predetermined period of time elapses. In response to the control signal being received, the switch cuts the connection between the power supply and the voltage regulator preventing the processor from receiving the driving power from the voltage regulator. 
     The description associated with  FIGS. 1 through 8  is equally be applicable to the method of  FIG. 9 ; accordingly, the description is not repeated here. 
     The units described herein may be implemented using one or more hardware components, and/or hardware components implementing one or more software components. For example, the hardware components may include switches, resistors, diodes, transistors, capacitors, power supplies, batteries, voltage regulators, and processing devices. A processing device may be implemented using one or more general-purpose or special purpose computers, such as, for example, a processor, a controller, a microcontroller, an arithmetic logic unit, a digital signal processor, a microcomputer, a field programmable array, a programmable logic unit, a microprocessor or any other device capable of responding to and executing instructions in a defined manner. The processing device may run an operating system (OS) and one or more software applications that run on the OS. The processing device also may access, store, manipulate, process, and create data in response to execution of the software. For purpose of simplicity, the description of a processing device is used as singular; however, one skilled in the art will appreciated that a processing device may include multiple processing elements and multiple types of processing elements. For example, a processing device may include multiple processors or a processor and a controller. In addition, different processing configurations are possible, such as processors operating in parallel. 
     The software may include a computer program, a piece of code, an instruction, or some combination thereof, to independently or collectively instruct or configure the processing device to operate as desired. Software and data may be embodied permanently or temporarily in any type of machine, component, physical or virtual equipment, computer storage medium or device, or in a propagated signal wave capable of providing instructions or data to or being interpreted by the processing device. The software also may be distributed over network coupled computer systems so that the software is stored and executed in a distributed fashion. The software and data may be stored by one or more non-transitory computer readable recording mediums. 
     The non-transitory computer readable recording medium may include any data storage device that can store data which can be thereafter read by a computer system or processing device. Examples of the non-transitory computer readable recording medium include read-only memory (ROM), random-access memory (RAM), CD-ROMs, magnetic tapes, floppy disks, and optical data storage devices. Also, functional programs, codes, and code segments that accomplish the examples disclosed herein can be easily construed by programmers skilled in the art to which the examples pertain based on and using the flow diagrams and block diagrams of the figures and their corresponding descriptions as provided herein. 
     The above described systems, devices and methods are described in connection with a vehicle; however, the system, devices, and method also may be used in connection with other devices using a power supply. As a non-exhaustive illustration only, other devices may include to mobile devices such as a cellular phone, a personal digital assistant (PDA), a digital camera, a portable game console, and an MP3 player, a portable/personal multimedia player (PMP), a handheld e-book, a portable laptop PC, a global positioning system (GPS) navigation, a tablet, a sensor, and devices such as a desktop PC, a high definition television (HDTV), an optical disc player, a setup box, a home appliance, and the like that are capable of being connected to a power supply. 
     A number of examples have been described above. Nevertheless, it should be understood that various modifications may be made. For example, suitable results may be achieved if the described techniques are performed in a different order and/or if components in a described system, architecture, device, or circuit are combined in a different manner and/or replaced or supplemented by other components or their equivalents. Accordingly, other implementations are within the scope of the following claims.