Abstract:
An information handling system allocates power for internal use and to support peripheral device operations by managing bi-directional power transfer at plural cable ports. A user interface presents to an end user the detected power transfer states and alternative states for alternative power and data transfer rates with changed cable and port connections. The user interface provides users with real time information for power and data transfer configurations that help optimize information handling system performance.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    Field of the Invention 
         [0002]    The present invention relates in general to the field of information handling system cabled connections, and more particularly to information handling system multiport power management. 
         [0003]    Description of the Related Art 
         [0004]    As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems. 
         [0005]    Information handling systems continue to shrink in size and grow in capabilities. Improvements in processing capabilities have allowed information handling system manufacturers to pack increased processing capability into housings of decreased size while increasing battery life with power savings measures. In particular, many end users appreciate information handling systems that have thin housings for ease of mobility and that have power savings logic and large batteries for increased operating times when external power is not available. 
         [0006]    One difficulty faced by information handling system manufacturers when designing low-profile portable systems is providing the amount of power that processing components need when operating at full capacity. Often, portable information handling systems include powerful components that will draw current at rates in excess of the rates that an external power supply can provide. Power saving logic drives down current draw during idle operations, however, initiation of an application or hardware operation tends to spike power consumption and thus current draw in large variances that can occur unexpectedly. As one example, many tablet information handling systems powered by USB adapters cannot power up through a boot sequence without a battery charge to supplement external power. 
         [0007]    Thin housings used for low-profile information handling systems present several difficulties for power solutions acceptable to the large power consumption variance that can occur. One difficulty is that power and communication connectors located along the housing edge have minimal space. In small tablet configurations, a single USB connector is sometimes used for both power can communication. Larger tablet configurations and clamshell/convertible configurations tend to have additional cable connections, such as a dedicated power connector and display connector as well as multiple USB and other data connectors; however, the housing edge space comes at a premium in thin solutions due to structural and electrical considerations. Even where a dedicated power connector is included, the space available for power management, such as capacitors to manage power surges, is minimal, as is the space available for a battery. 
         [0008]    One recent trend that aids power management is the use of various peripheral ports to both send information and generous amounts of power. USB Type C connectors and ports, for example, may provide as much as 100 W of power. DisplayPort connectors and ports using a USB type of interface support similar power transfer amounts. In addition, power transfer is bi-directional so that an information handling system can provide power to peripheral devices or can receive power when interfaced with a device capable of providing power. However, since many ports have similar footprints designed to take minimal housing space, end users face some confusion regarding which port is appropriate for which cable. Further, an end user may not understand that a peripheral port is providing power to an information handling system or, in some cases, which peripheral port is providing power, so that the end user will expect similar performance at an information handling system as cables are inserted and removed. In fact, the availability of external power can impact the capability of processing components to operate at full capacity. Further, connecting and disconnecting external power in an unexpected manner can introduce unpredictable power surges that lead to system crashes or component failures. 
       SUMMARY OF THE INVENTION 
       [0009]    Therefore, a need has arisen for a system and method which provides power to an information handling system in a flexible manner. 
         [0010]    In accordance with the present invention, a system and method are provided which substantially reduce the disadvantages and problems associated with previous methods and systems for powering an information handling system. A power manager monitors power sources coupled to data and power ports of an information handling system to selectively accept power simultaneously from plural power sources. Available power state configurations are tracked and presented to an end user with a user interface that optimizes power transfer at the information handling system for a given operating condition, such as based on available power sources, battery charge, system power consumption states, data transfer needs, etc. . . . Power and data ports are monitored for cable motion so that changes in power state are anticipated and adapted to at the information handling system without disrupting system operation. 
         [0011]    More specifically, an information handling system processes information with a processor and memory disposed in a housing. The housing has plural ports that accept power cables and data cables, such as USB Type C connectors and DisplayPort connectors. An embedded controller running power manager firmware code stored in flash memory manages power at the information handling system, including accepting power from external sources at a charger to apply the power to run components and charge a battery. The power manager reports available power to a user interface at an operating system level so that an end user is presented with available power states based upon the power capabilities of external devices, such power adapters and peripheral devices configured to provide power to the information handling system through USB Type C cables and ports. The power manager configures multiple power sources to match power impedance so that the multiple sources are able to simultaneously provide power to the information handling system. Cable ports are monitored for motion of a cable that indicates a power source may be disconnected so that the power manager can adapt the system to changes in the power source configuration before the change occurs. In one embodiment, a power cable is connected with magnetic pogo pins that are reversibly connectable. A center pin provides ground and two outer pins provide communication and power so that the power manager detects the outer pin function before configuring the power source for power transfer using the communication pin. 
         [0012]    The present invention provides a number of important technical advantages. One example of an important technical advantage is that an end user is provided with a user interface that allows the end user to understand and manage power application from multiple external devices so that the end user can select optimal power and data transfer configurations. Multiple power sources couple to an information handling system provide power simultaneously to improve power efficiency and ensure that full power is available to the information handling system when any one power source is not sufficient to meet the information handling system&#39;s power needs. Active monitoring of cable connections at the information handling system provide a transition time between a cable disconnect and power loss so that the information handling system reconfigures to new power source configurations before existing power supply is lost from a disconnecting source. In one embodiment, a reversible magnetic power connector provides power and communication for coordinating power transfer through three pin connector having the ground pin in a center location. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The present invention may be better understood, and its numerous objects, features and advantages made apparent to those skilled in the art by referencing the accompanying drawings. The use of the same reference number throughout the several figures designates a like or similar element. 
           [0014]      FIG. 1  depicts a portable information handling system interfaced with plural peripheral devices that provide power; 
           [0015]      FIG. 2  depicts a block diagram of an information handling system configured to manage application of power from plural power sources; 
           [0016]      FIG. 3  depicts a user interface presented at an information handling system that aids end user configuration of external device connections to enhance power transfer from multiple external sources; 
           [0017]      FIG. 4  depicts a flow diagram of a process for presenting end user cable configurations that enhance power transfer; 
           [0018]      FIG. 5  depicts a block diagram of an information handling system configured to adapt plural external power source impedances to maintain a common system droop; 
           [0019]      FIG. 6  depicts a flow diagram of a process to adapt plural external power source impedances to maintain a common system droop; 
           [0020]      FIGS. 7A, 7B and 7C  depict a data connector and port having a motion detector to provide a transition time for power transfer reconfiguration; 
           [0021]      FIGS. 8A and 8B  depict current levels at power source transition with and without the power transition time; 
           [0022]      FIG. 9  depicts a three pin reversible magnetic connector that couples to a power source; 
           [0023]      FIGS. 10A and 10B  depict a circuit diagram of one example of a power controller that accepts power from a reversible power connector; 
           [0024]      FIG. 11  depicts a flow diagram of one example of a process for managing power provided at a reversible power connector; 
           [0025]      FIGS. 12A and 12B  depict a circuit diagram of another example of a power controller that accepts power from a reversible power connector; and 
           [0026]      FIG. 13  depicts a flow diagram of another example of a process for managing power provided at a reversible power connector. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    An information handling system accepts power from multiple power sources, including peripheral devices, by intelligently managing power transfer between the multiple power sources. For purposes of this disclosure, an information handling system may include any instrumentality or aggregate of instrumentalities operable to compute, classify, process, transmit, receive, retrieve, originate, switch, store, display, manifest, detect, record, reproduce, handle, or utilize any form of information, intelligence, or data for business, scientific, control, or other purposes. For example, an information handling system may be a personal computer, a network storage device, or any other suitable device and may vary in size, shape, performance, functionality, and price. The information handling system may include random access memory (RAM), one or more processing resources such as a central processing unit (CPU) or hardware or software control logic, ROM, and/or other types of nonvolatile memory. Additional components of the information handling system may include one or more disk drives, one or more network ports for communicating with external devices as well as various input and output (I/O) devices, such as a keyboard, a mouse, and a video display. The information handling system may also include one or more buses operable to transmit communications between the various hardware components. 
         [0028]    Referring now to  FIG. 1 , a portable information handling system  10  is depicted interfaced with plural peripheral devices that provide power. In the example embodiment, portable information handling system  10  has a convertible configuration with housing  12  having a keyboard  14  integrated in a main portion and a display  16  integrated in a lid portion rotationally coupled to the main portion. For instance, portable information handling system converts between closed, clamshell open and tablet configurations. In alternative embodiments, alternative housing configurations may be supported, such as tablet configurations and desktop configurations. Information handling system  10  obtains power to run components and charge an integrated battery through data ports that that communicate information and also include power transfer wires, such as a USB data port  18  and a graphics data port  20 . For example, a Type C USB  18  port accepts USB cables  26  from a peripheral display device  22 , a printer  24  or other types of peripheral devices that have bi-directional power transfer to both receive power from information handling system  10  and provide power to information handling system  10 . As another example, a DisplayPort port  20  accepts a DisplayPort cable  28  from peripheral display device  22  to both receive power and transfer graphics data from information handling system  10  to display  22 . In addition to receiving power from peripheral devices, information handling system  10  has a power connector port  30  that accepts power from an AC-to-DC adapter. 
         [0029]    In operation, information handling system  10  configures to receive and provide power with external devices based upon communications with each external device. Power connector port  30  includes a Type C CC or vendor specific PSID communication with AC-to-DC adapter  32  that exchanges power characteristics so that information handling system  10  draws an appropriate current without overloading adapter  32 . Serial data ports  18  and graphics ports  20  include dedicated data lines defined by a communications protocol, such USB 3 or DisplayPort protocols, which also defines power transfer handshakes. For example, each peripheral includes a power source  34  that provides power locally to run the peripheral, such as from an external power source  38  or from power provided by information handling system  10  through data cable. In addition, in some instances power sources  34  may provide power to information handling system  10  through the data cable. The capability of each peripheral device is communicated with power characteristics through the data cable, such as with the USB or DisplayPort protocols. Information handing system  10  receives and sends power between each external device based upon the communicated capabilities and configuration of each external device. For example, information handling system  10  may take power from some peripheral devices while providing power to run other peripheral devices based upon the capability of an external power adapter  32 . 
         [0030]    Referring now to  FIG. 2 , a block diagram depicts an information handling system  10  configured to manage application of power from plural power sources. A hardware layer includes processing resources to store and execute instructions. For example a central processing unit (CPU)  38  executes instructions in combination with a random access memory (RAM)  40 . A chipset  42  includes processing resources and flash memory that execute firmware instructions. For instance, an embedded controller  44  manages communication with power resources and input/output devices. A graphics controller  46  manages communication with integrated and external graphics devices, such as by generating pixel values for presentation of visual images at a display communicated through graphics port  20 . Embedded controller  44  interfaces with a USB hub  48  or other type of serial port hub to manage communication of data and power at USB port  18 . Movement of cables into and out of ports  18  and  20  is monitored by a motion detector  50 , as set forth in greater detail below. A charger  54  adapts power for specific uses, such as charging a battery or powering various busses with various voltage and current levels. 
         [0031]    The hardware layer is managed at a physical level by instructions stored in persistent memory as firmware in a firmware layer. Generally, physical component interactions are managed by a Basic Input/Output System (BIOS) or similar device running on embedded controller  44  and/or related microprocessors. For example, BIOS  56  includes modules that manage power, such as a power manager  58  and a port power engine  60 , both described in greater detail below. BIOS  56  interacts with an operating system layer to provide information to and accept inputs from an end user. For example, a port power user interface  62  presents to the end user the available power transfer states  64  so the end user may select cable and port connections that provide optimal power transfer configurations for the end user. As an example, port power engine  60  detects connections for USB ports  18  and graphics ports  20  with peripheral devices and analyzes the power capabilities of each peripheral device to suggest the port and cable connections that will provide the most rapid battery charge. If, for instance, an end user plugged a USB Type C display into a port that is not DisplayPort ALT mode capable, the end user is provided with a graphical suggestion of a port location on the information handling system that will provide power transfer with the Type C display. In one example embodiment, the end user is presented with a user interface that depicts various combinations of port connections and the power transfer state of each combination. Port power engine  60  monitors all port plug status changes and port instantaneous power draws to maintain a port status table referenced by port power user interface  62 . Port power engine  60  manages power transfer at the plural ports based upon detected port cable connections, detected power source and detected power transfer configurations, including peripheral devices that source and/or sink power. By tracking total instantaneous port power allocation and system power budgets, port power engine  60  dynamically adjusts system resources based on the system and plugged device power status changes to direct the user through power user interface  62  of an appropriate match of peripheral capabilities to port capabilities. This active monitoring helps to ensure that peripheral devices that draw power will also have adequate power through available port resources, such as when a peripheral device that was providing power transitions to receiving power from the information handling system. As an example, when on battery power, port power engine may suggest use of a display having less power consumption to present information; on the other hand, if the displays have external power to provide to the information handling system, port power engine may suggest power be provided from the display having the greatest power transfer rate. In one embodiment, other factors may be considered, such as video quality when visual images are presented by streaming using battery versus external power. 
         [0032]    Referring now to  FIG. 3 , a user interface  64  presented at an information handling system  10  is depicted that aids end user configuration of external device connections to enhance power transfer from multiple external sources. Information handling system  10  detects all cables connected to ports, the presence/absence of an external power adapter  32 , a battery charge state and data transfer configurations, and then presents available power transfer states at user interface  64 , such as power states available to accept external power and to power external devices. In the example embodiment, an end user is informed that a display coupled to a port is not currently providing power and is pointed to a different port that the end user can use that will provide power transfer from the display to the information handling system. User interface  65  depicts different power transfer states based upon power use and need, and also based upon data use and need. For example, a docking station provides an interface with a display  22  and power through a USB Type C cable. If information handling system  10  has a low battery charge and display  22  provides power, user interface  64  presents the option of directly coupling display  22  to a DisplayPort port of information handling system  10  to increase charge rate by accepting power from both display  22  and the docking station. If printer  26  does not provide power through its cable, user interface  64  suggests interfacing printer  26  through the docking station to open up a port for a direct connection by display  22  that can provide power. If, on the other hand, information handling system  10  has a full battery charge and power provided by the docking station is adequate for running processing components, user interface  64  will not disrupt the end user with other power and data cable configurations. Other situations that may arise include power transfer from information handling system  10  to a peripheral, such as display  22 , where the display does not have its own power source. For example, user interface  64  may suggest unplugging a display  22  that draws power during battery charge so that the full power capability of the system is available to charge the battery instead of running peripheral devices. In such an example situation, user interface  64  will suggest swapping a display  22  that provides power and is connected to a docking station with a display  22  interfaced directly to an information handling system port that does not provide power or draws power. As another example, where power into an information handling system can be supplemented by a fully-charged battery as needed, a lower power-in state may be suggested for a configuration that will provide a greater data transfer, such as where a user is streaming a move. 
         [0033]    Referring now to  FIG. 4 , a flow diagram depicts a process for presenting end user cable configurations that enhance power transfer. At step  70 , connections at each port are queried for power configuration parameters and each port is configured to accept or provide power as appropriate. In various embodiments, two or more ports may simultaneously receive power from external devices, such as a power adapter or a peripheral. At step  72 , the ports are monitored to detect any change is port connections, and if no change is detected the process returns to step  70 . If a change in port configuration is detected at step  72 , the process continues to step  74  to compare the configured power into the information handling system with the available power from the newly detected port configuration. At step  76  a determination is made of whether a configuration is available with more power available to the information handling system than in the present configuration. If not the process continues to step  70 . If a configuration with more power transfer is available, the process continues to step  78  to suggest a modified cable configuration to the end user through the power state user interface. 
         [0034]    Referring now to  FIG. 5 , a block diagram depicts an information handling system  10  configured to adapt plural external power source impedances to maintain a common system droop. Information handling system  10  has a power controller  44 , such as embedded controller, that manages system power through a charger, such as by outputting power to one or more system busses sourced from external power or a battery. For example, a power manager  58  includes local power characteristics  36  that the power controller communicates with external power sources to manage power transfer. Power manager  58  coordinates with multiple external power sources to accept power from plural sources simultaneously, such as from one or more power adapters and/or one or more peripheral devices  80 . In the example embodiment, each of plural peripheral devices  80  includes a power manager  58  and locally stored power characteristics that are communicated with information handling system  10 . By tracking power characteristics  36  of each external device coupled to it, each power manager  58  adjusts power output characteristics to provide power at a level that works with other devices simultaneously transferring power. For instance, in some example embodiments power is provided to an information handling system simultaneously through plural USB Type C ports, plural DisplayPort graphics ports, various combinations of USB data ports, graphics ports and power adapter ports that are included to transfer power without data (other than power source identification and characteristics). 
         [0035]    In one example, power manager  58  of information handling system  10  identifies with USB and DisplayPort power handshakes the output rating of each attached peripheral device using digital communication lines. For peripheral devices that have compatible power transfer capabilities, the power manager  58  commands an output impedance that each peripheral device  80  configures itself to output so that the power output of each peripheral device matches during changes of current draw by information handling system  10 . In one example embodiment, the power manager  58  of information handling system  10  retrieves the current rating of each peripheral device  80  and applies the information handling system voltage droop to determine a peripheral device impedance setting according to the formula: 
         [0000]    
       
         
           
             
               Rout 
               imp 
             
             = 
             
               
                 V 
                 droop 
               
               
                 Isource 
                 rating 
               
             
           
         
       
     
         [0036]    where;
       Rout imp  Adapter output impedance.   Vsys droop  System Droop allowed from nominal.   Isource rating  Source power rating.       
 
         [0040]    Alternatively, power manager  58  communicates a voltage droop setting to each power-capable device  80  so that each device  80  sets an output impedance that will match that provided from information handling system  10 . The programmed output impedance will be system dependent and inversely proportional to the current rating of each peripheral device  80 . For example, with two peripheral devices  80  coupled to information handling system  10  having a system output voltage droop of 200 mV over the system demand, a source rated at 2.5 A and a source rated at 4.5 A would set their output impedance at 80 mOhms and 40 mOhms respectfully. In the event that the output impedance is determined at the peripheral device  80 , information handling system  10  provides the voltage droop so that the peripheral device may compute the output. Advantageously, providing power from multiple external sources allows information handling system  10  to draw its maximum rated power where drawing current from just one external device would not provide maximum rated current. With matched impedance, all power sources will provide proportional power relative to the maximum power available. Power manager  58  can selectively adapt to receive power from just one device as desired during times of low power draw so that extra charger devices of peripheral devices may enter a power saving state. End users will not have an impact with reduced performance since a battery can supplement current draw until a second power source is returned to an active state. Operating power sources at moderate levels of current production helps to increase power transfer efficiency, which may be coordinated through transfer of power efficiency factors with the power characteristics  36 . 
         [0041]    Referring now to  FIG. 6 , a flow diagram depicts a process to adapt plural external power source impedances to maintain a common system droop. At step  82  a new power source is detected at a device port, such as a power port that couples to a power adapter or a data port that couples to a data cable. At step  84  a determination is made of whether the new power source is the only available power source or one of multiple power sources. In one example embodiment, a power source may be considered as the only power source if the power source has adequate current to meet the maximum current draw of the information handling system. If the power source is the only power source, the process continues to step  86  for the system controller, such as a power manger running on an embedded controller, to detect and negotiate power source capabilities through a control interface, such as USB, DisplayPort, or PSID interfaces. If at step  84  the new power source is not the only power source, the process continues to step  88  for the system controller to identify each attached power source and confirm that the power sources are compatible with a multi-power source load contribution. If a power source is not capable of configuring for multiple power source sharing, then the source may be treated as the only source or turned off to prevent power contribution and the process continues to step  86  to configure power sources accordingly. 
         [0042]    Once all power sources are identified that are compatible with power sharing, the process continues to step  90  to configure the power sources for power sharing. The system controller communicates the system power profile to each of the power sources, such as the allowed voltage droop at the system and the maximum current available from each power source. In response to the system power profile information, the information handling system and power sources set their power characteristics to desired settings. For example, based upon the voltage droop provided from the information handling system, each power source sets a matching power impedance to allow each power source to contribute to system power proportional to their output rating. At step  92 , the status of the power sources is changed to reflect the updated impedance settings and the process returns to step  82  to monitor a change in status of power sources. If at step  92  the power sources do not match or successfully configure to share power contribution, the process returns to step  90  to reattempt configuration. 
         [0043]    Referring now to  FIGS. 7A, 7B and 7C , a data connector  94  and port  18  are depicted having a motion detector  50  to provide a transition time for power transfer reconfiguration. As presented in  FIG. 7A , on full insertion of cable plug  94  into port  18 , motion detector  50  is pressed backwards to provide a Vdetect signal that indicates full insertion of cable plug  94  into port  18 . At full insertion, power lines  102  in port  18  receive power from power lines of cable plug  94  so that power is provided to an information handling system charger coupled to port  18 . As presented in  FIG. 7B , on initiation of withdrawal of cable plug  94  from port  18  motion detector  50  closes a switch that indicates a withdrawing motion has begun before power is removed from power lines  100  of port  18  since a power connection remains for at least part of the withdrawing motion as power lines of cable plug  94  remain in contact with power lines  100  in port  18 .  FIG. 7C  illustrates that a transition time  102  is provided between the change in value of Vdetect and the change in power applied by cable plug  94  at Vbus. In a multi-plug power situation as described above with respect to  FIG. 6 , transition time  102  provides adequate warning to the power manager of a change in available external power so the power manager can reconfigure power into the information handling system before the available power in changes. Although  FIG. 7  depicts a motion detector  50  in the form or a switch that is triggered by full or partial insertion of a plug, in alternative embodiments other types of motion detectors may be used, such as an infrared sensor that monitors plug  94  or a Hall sensor that uses magnetic interactions to detect motion or full insertion of plug. 
         [0044]    Referring now to  FIGS. 8A and 8B , current levels at power source transition are depicted with and without the power transition time. Information handling system  10  has an allowed voltage droop that defines how much voltage is allowed to drop when current draw increases. In the event of an unplugging motion of a power source in a multi-power source configuration, voltage droop is expected when power ceases from the unplugged power source and until the power manager and remaining power source are able to re-establish the designed Vbus. System voltage is re-established by a combination of reducing current draw by the information handling system from the remaining power source and decreasing impedance of the remaining power source so that its current output increases. In order to absorb some of the increase current demand from the remaining power source during a transition time, capacitance may be added to the information handling system, however, such capacitance comes at a cost in both components and board space. 
         [0045]      FIG. 8A  depicts the increase in current draw and droop in voltage that can occur in one example embodiment at the unplugging of a power source without prior notice. Vbus drops at the unplug event to a Vth level that triggers a detection of a power source change. In response to the voltage droop caused by the primary Vbus unplug event, adapter current to supply power at a secondary Vbus spikes to a high current value in attempt to raise the system voltage to a target value. The ramp in current increase from the remaining power source stresses current output capacity and takes a ramp up time that can respond to slowly to maintain voltage at a level adequate to keep the information handling system running. In contrast,  FIG. 8B  depicts voltage and current response where a motion detector provides warning of an unplug event before power is cut off due to the unplug event. Upon motion detection at a port plug, the power manager responds by preparing the information handling system to run without power provided by the port. The transition may involve a variety of steps that will reduce the impact of a sudden loss of current from the port. For example, the power manager reconfigures the power transfer impedance for the two power sources to have power provided only by the power source that does not have motion detected. As another example, power provided from an integrated battery may supplement current before a disconnect of the cable from the port where motion is detected. Other examples may include reconfiguring of the information handling system to receive power from other cables and ports that have power transfer capability that is not in use. In each instance, the power transition warning provided by motion detection of a cable at a power-providing port gives the power manager time to initiate a transition to removal of the power source before the power source is lost so that the voltage droop and related current inrush are minimized. In  FIG. 8B , the example embodiment initiates a power current increase available from the secondary power source before the primary power source is removed. 
         [0046]    Referring now to  FIG. 9 , a three pin reversible magnetic connector  106  is depicted that couples to a power source. In the example embodiment, a power adapter  32  provides current through a power cable  104  to power connector  106  with three power pins disposed in a linear arrangement. Power pins  108  align with power connector pins  110  in a reversible manner. In the example embodiment, power pins  108  and power connector pins  110  couple together and are held together with magnetic attraction, such as by having a magnet and/or ferromagnetic material disposed in the housing of information handling system  10  and magnetic connector  106 . In one embodiment, the pins include a spring bias that detects a separating motion of a cable from a housing to provide warning of a changed power configuration as set forth above with respect to motion detection. 
         [0047]    Referring now to  FIG. 10 , a circuit diagram depicts one example of a power controller that accepts power from a reversible power connector. Power cable connector  106  has three pins disposed in a linear configuration and having a ground pin in the center location with power and communication pins located at end positions. The housing power connector  110  also has three pins in a linear arrangement, however, the power and communication pin locations on opposing ends of the linear arrangement are configurable depending upon the orientation of power cable  106 . Power controller circuit  112  detects the orientation of power cable  106  relative to power connector  110  and configures the outer two pins to accept power or communication based upon a determination of the power cable pin that has contacted it. In other words, the housing power connector outer pins adapt by automated configuration to perform either current of information transfer based upon the orientation at which the power cable couples to the housing. 
         [0048]    When power adapter  32  pins  108  contact information handling system pins  110 , ground is known since ground is located in a middle position, but power and communication pins may align on either side of information handling system  10  based upon power cable orientation. Power controller circuit  112  determines which outer pin  110  has connected to power and which has connected to communication, and then configures itself to accept power and communications accordingly. In at idle state awaiting a power cable connection, Q8 is self-biased ON by Vrp provided at the power V+ and communication CC nodes. At connection of a power cable connector pins  108  to pins  110 , the external adapter detects Rd and in response outputs 5V at Vbus for the V+ pin and broadcasts power source capability through the CC pin. The 5V of power travels via Q2 to a low drop out regulator (LDO)  114  that outputs Vcc_ec to power embedded controller  44  to execute a power manager that manages power input at housing power connector  110 . 
         [0049]    Once embedded controller  44  is powered by LDO  114 , a power manager stored in flash memory executes to boot the embedded controller in a pre-BIOS mode that allows determination of the orientation of power cable  106  relative to power connector  110 . In the example embodiment, embedded controller  44  reads the value of pin FWD_EN and optionally REV_EN to set the pins  110  for power or communication inputs. After the embedded controller negotiates power transfer characteristics, using the communications line CC, power transfer ramps up on the power line until Vbus_in exceeds the set ACOK limit, at which time embedded controller  44  enables Q2 to set the input current line to charger  54 . In this manner, higher current levels are passed to charger  54  after the power-in line is identified. 
         [0050]    Referring now to  FIG. 11 , a flow diagram depicts one example of a process for managing power provided at a reversible power connector. The process starts at step  116  with attachment of an external power source to a housing connector. At step  118 , the external power source detects the connection Rd and in response enables voltage at Vbus to output voltage from the power sources to the housing connector. At step  120 , the voltage from Vbus enters the connector with adequate current power an LDO with a minimal output to an embedded controller, such as 15 mA. At step  122 , power provided from the LDO boots the embedded controller to a pre-BIOS operational state. The LDO powers the embedded controller with Vbus provided at either of the outside connection pins. At step  124 , the embedded controller analyzes the power in to determine which housing connector pin is receiving the power by determining which connector pin has a higher voltage state. If the Vbus 1  has a lower voltage, the process continues to step  126  to enable bus line  1  as the communication link. If Vbus 1  has a higher voltage, the process continues to step  128  to enable bus line  2  as the communication link. At step  130 , the charger in the information handling system initiates a power handshake through the communication line to negotiate a power exchange contract. At step  132 , the external power source initiates power transfer at the negotiated contract. At step  134 , the charger provides the negotiated power transfer contract information to the embedded controller and, at step  136 , the embedded controller sets the power transfer based upon system need. The process ends at step  138  with the information handling system and external power source configured to exchange power with correctly configured power and communication lines. 
         [0051]    Referring now to  FIG. 12 , a circuit diagram depicts another example of a power controller that accepts power from a reversible power connector. In the example embodiment of  FIG. 12 , a manufacturer specific power system identifier (PSID) is communicated to provide external power source characteristics instead of standardized CC power communications. Embedded controller first attempts communication with a standardized CC protocol and, if communication is not found, determines that the connector is not a Type C USB connector. In response, embedded controller  44  initiates alternative power protocol communications using vendor specific and/or USB 2 communication protocols to establish power transfer. A soft start FET  140  is disposed on the communication and power lines to prevent arching or other damage in the event of a current in rush from a 20V power source. In addition, if an external power adapter is detected but Rd is not detected, embedded controller  44  checks an AC_OK signal to determine the proper type of protocol ID, such as a vendor specific PSID or a microUSB 2.0 connector. For example, if a 5V input is detected without a Type C Rd indication, a microUSB is determined; and if a voltage of greater than 5V is detected without a Type C Rd indication, a vendor specific power source is determined. 
         [0052]    Referring now to  FIG. 13 , a flow diagram depicts another example of a process for managing power provided at a reversible power connector. The process starts at step  142  with connection of an external power source, provides power through an LDO to the embedded controller at step  144 , and initiates pre-BIOS logic of the embedded controller at step  146 . At step  148 , the line that accepts the 5V is identified so that the appropriate communication line is configured at either step  150  or  152 . At step  154 , the charger starts Type C CC logic to identify the power source and negotiate the power transfer. At step  156 , failure of power source identification is detected, for example by a lack of response to a CC protocol message. At step  158 , the embedded controller initiates power handshakes by alternative protocols, such as USB 2 protocols or manufacturer specific PSID protocols. At step  160 , embedded controller  44  sets an appropriate power configuration based upon successful communications with an alternative protocol and, at step  162  the process ends. 
         [0053]    Although the present invention has been described in detail, it should be understood that various changes, substitutions and alterations can be made hereto without departing from the spirit and scope of the invention as defined by the appended claims.