Abstract:
An enclosure design facilitates heat dissipation from a space-limited computer core device. An external computer platform is provided to connect the computer core device, the external computer platform including a fan that provides an air flow to the connected computer core device. The computer core device and the computing platform may be tightly connected by connectors located on their respective enclosure walls. Both the computer core device and the external computing platform are provided air inlets and outlets on their respective enclosures. When connected, an air inlet of the computer core device faces an air outlet of the external computing platform such that a single cooling air flow flows through the external computing platform and the computer core device. The external computing platform may include a built-in fan to blow air into or draw air from the matching air inlets and outlets.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application is related to and claims priority of U.S. provisional patent application (“Copending Provisional application”), Ser. No. 61/776,682, entitled “Modular Computer and Thermal Management”, filed on Mar. 11, 2013. The disclosure of the Copending Provisional application is hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to applications of modular computer cores. More particularly, the present invention relates to the use of a hybrid circuit including a high-power processor and a low-power processor to provide a selectable “thermal design power” (TDP) in a thermal module together with an air-flow design. 
         [0004]    2. Discussion of the Related Art 
         [0005]    In recent years, small and thin computing devices are highly favored. Some examples of small and thin computing devices include the iPad and the iPhone from Apple Computer, Inc., the “ultrabooks” notebook computers from Intel Corporation and its partners, and the ultra-thin “Android smartphones” from Google, Inc. and its partners. To support these “ultra” devices, microprocessor manufacturers have provided low-power microprocessors (e.g., the ARM microprocessors, or fan-less x86 microprocessors). These microprocessors—which dissipate less than 3 W TDP (i.e., 3 watts of “Thermal Design Power”)—are primarily targeted for basic applications. To execute more advanced applications, higher power microprocessors are needed. But microprocessors that have a TDP that is higher than 3 watts require a proper thermal module for heat dissipation. In addition, the size of a typical ultra-computing device (i.e., roughly, the size of a smartphone) makes it difficult to squeeze a proper thermal module into the limited space. Other constraints on such a device include: (i) the device as a whole has to be as light as possible; (ii) the form factor has to be handheld size; (iii) noise has to be kept to a minimum, so as to be non-intrusive on the user carrying it very closely to the body (e.g., in a shirt pocket); and (iv) the exterior case temperature has to be kept low enough to be handheld permissible. Therefore, a new thermal module that is able to dissipate heat of a high-power microprocessor within the limited space of an ultra-computing device is desired to support advanced applications. 
         [0006]    Metal blocks have been used as heat sinks that are mounted on low-power fan-less microprocessors to dissipate heat. It is also common to use metal chassis or cases to serve as passive heat sinks for low-power microprocessors. However, to transfer heat away from a higher power microprocessor, a much larger and more complete thermal module is required. Such a thermal module may include a heat dissipation plate, a heat pipe, and a heat sink. Further, it is customary also to include an integrated fan to increase airflow over the heat sink to expel the heated air out of the chassis or case quickly. 
         [0007]    Excluding the display and the touch panel, the body of a typical ultra-thin device is less than one centimeter thick. A bulky heat dissipation block does not fit in this thickness. In addition, it is impossible to put a conventional cooling fan within the confines of the smartphone-size computer. It is a challenge to computer supplies to find a design that cools down a smartphone size computer in which a high-power microprocessor is used. In an attempt to provide such a solution, some computer thermal management companies (e.g., SUNON in Taiwan) designed powerful “mighty mini-fans” that fit into the limited space. However, these new “mini” products do not generate enough airflow to cool a high-power microprocessor in an effective mariner. 
       SUMMARY OF THE INVENTION 
       [0008]    In accordance with one embodiment of the present invention, a design for an ultra-thin (or smartphone-size) modular computer (“computer core”) is created to dissipate heat from a high-power microprocessor without requiring a tightly integrated centrifugal fan. In that design, the fan is placed in an external computing platform (“computing device”) that is separated from the computer core. In one embodiment, the computer core and the computing device are provided separate enclosures. The computer core and the computing device may be tightly connected to form an integrated computing device by connectors residing on their respective enclosure walls. A locking mechanism to secure the connection may also be provided. 
         [0009]    According to one embodiment of the present invention, the computer core provides the computational power for the integrated computing device, while the computing device provides the power source, and peripheral interfaces for the integrated computing device. In one embodiment, both the enclosures of the computer core and the computing device have air inlets and air outlets formed by openings in their respective walls. Each matching pair of air inlet and outlet allows an airflow to flow through both the computer core and the computing device, when they are connected. In one embodiment, the computing device has a built-in fan to blow air into or draw air from the computer core through the matched air inlet and air outlet at the connection. In one embodiment, the computer core has an optional heat dissipation plate, heat pipes, and a heat sink mounted on a microprocessor for heat dissipation. In one embodiment, the computer core may have a metal chassis or case, which serves as a passive heat sink for heat dissipation. In another embodiment, the computer core includes a hybrid circuit consisting of an ARM microprocessor and an x86 microprocessor. One of the microprocessors may be selected for executing basic or advanced applications, according to whether the availability of a cooling airflow in the integrated computing device. 
         [0010]    The present invention provides an advantage by providing the hybrid circuit that includes a high-power microprocessor and a low-power microprocessor, so that a selectable thermal design power (TDP) is available to a user. As a result, an appropriate TDP is made available when needed. 
         [0011]    The present invention provides an advantage by separating a fan customary in a conventional integrated thermal module. The fan in the computing device can blow air into or draw air from a space-limited computer core without requiring space in the enclosure of the computer core. 
         [0012]    The present invention provides an advantage by allowing different fan sizes for different computing devices. The different fan sizes allow a wide range of adjustable air volumes and flows be made available. 
         [0013]    The present invention provides an advantage by accommodating a heat sink at an end or edge of the computer core, so as to facilitate and to take advantage of the convection or “chimney” effect when the computer core is oriented vertically rather than horizontally. Air heated by the components in the integrated computing device (e.g., the microprocessor) tends to rise, thereby creating a natural air flow in a general “vertical” direction. The present invention takes advantage this effect by providing an orientation of the computer core which facilitates this air flow to enhance cooling heat dissipation means (e.g., a heat sink) and the microprocessor. 
         [0014]    The present invention provides an advantage to accommodate a heat sink at an end or an edge of the computer core. The position increases radiation from the heat sink when the heat sink is also used as an antenna for communication. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    A complete understanding of the present invention may be obtained by reference to the accompanying drawings, when considered in conjunction with the subsequent, detailed description, in which: 
           [0016]      FIG. 1  is a top view of computer core  200  and a partial view of connected computing device  100 . 
           [0017]      FIG. 2  is a sectional view of connected computer core  200  and computing device  100 , according to one embodiment of the present invention. 
           [0018]      FIG. 3   a  which is a top view of one implementation of computer core  200  using an x86 processor and an ARM processor. 
           [0019]      FIG. 3   b  is a section view of the implementation of computer core  200  of  FIG. 3   a  along its length through connector  220 . 
           [0020]      FIG. 4  is a block diagram showing one exemplary implementation of computing device  100  and computer core  200  being connected over a proprietary interface or an open interface, in accordance with one embodiment of the present invention. 
           [0021]      FIG. 5  shows flowchart  500 , which illustrates system booting operations carried out by connected computing device  100  and computer core  200 , according to one embodiment of the present invention. 
           [0022]      FIG. 6  is a block diagram illustrating interactions between integrated computing device  100  and computer core  200  with external devices  300  and  400 , according to one embodiment of the present invention. 
           [0023]      FIG. 7  is a sectional view of the chassis of computing device  100 , showing an antenna being placed thereon, according to one embodiment of the present invention. 
       
    
    
       [0024]    For purposes of clarity and brevity, like elements and components bear the same designations and numbering throughout the Figures. 
       DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0025]      FIG. 1  is a top view of computer core  200  and a partial view of connected computing device  100 . As shown in  FIG. 1 , computer core  200  is smartphone size and is designed to connect to computing device  100 . On base board  250 , computer core  200  includes central processing unit (CPU)  201   c , graphical processing unit (GPU)  201   g , embedded controller  201   e , and other computing components. In some embodiments, computer core  200  and computing device  100  are connected through base connector  220  and carrier connector  120  in any manner (e.g., horizontally, vertically, or with a rotation mechanism for an angle less than 270 degree). To simplify this detailed description, a component on computing device  100  is described as “carrier”, while a component on computer core  200  is described as “base”. The pins of these connectors are mapped functionally (e.g., USB pins, A/V pins, power pins, and data pins) to allow proper signals to flow between the computer core  200  and computing device  100 . Computer core  200  and computing device  100  are designed to have a brain-and-body division of labor—i.e., when connected, computer core  200  controls the operations of computing device  100  through communication between base embedded controller  201   e  and carrier embedded controller  101 . Computing device  100  has its own separate housing or enclosure, and includes carrier board  150 , which acts as a detachable extension board for computer core  200 . Carrier board  150  connects to user interfaces, such as a display, one or more touch panels, control buttons, audio interfaces, sensors, I/O connectors, and DC power supply  102  connector. In  FIG. 1 , these components are shown as part of I/O interfaces  113 . Computing device  100  may include a battery, which serves as a backup power source for computer core  200 . 
         [0026]    According to one embodiment of the present invention, computer core  200  includes base air inlet  215   a , which acts as an open port to allow air to flow into the enclosure housing computer core  200 , and base air outlet  215   b , which acts as an exit port. As the air flow through the disclosure between base air inlet  215   a  and base air outlet  215   b , the air is heated by the dissipated heat from components of base board  250 , such as central processing unit (CPU)  201   c , graphical processing unit (GPU)  201   g , and embedded controller  201   e . Likewise, computing device  100  includes carrier air inlet  115   a  provided by the openings or slots in the walls of the enclosure, or openings in the I/O connectors. These openings allow air to enter into the enclosure of computing device  100 . Computing device  100  also includes one or more carrier fans (e.g., carrier fan  115 ) to blow the air along air guide  115   c . Air guide  115   c  may have a pipe-like structure to guide the air to carrier air outlet  115   b . Carrier outlet  115   b  and base inlet  215   a  are positioned such that, when computing device  100  and computer core  200  are connected, air is blown from carrier outlet  115   b  into base air inlet  215   a . Alternatively, carrier fan  115  may cause the air to flow in the opposite direction, i.e., air is drawn from computer core  200  to computing device  100 , under a vacuum operation. In one embodiment, heat plate  215   d  is mounted on top of one or more of: GPU  201   g , CPU  201   c , or any other component that dissipates significant heat. Heat plate  215   d  transfers heat to heat pipe  215   e . Heat pipe  215   e  terminates at heat sink  215   f , which has a large surface area to allow heat dissipation into the external surrounding air with which it is in contact. 
         [0027]      FIG. 2  is a sectional view of connected computer core  200  and computing device  100 , according to one embodiment of the present invention. As shown in  FIG. 2 , computer core  200  is connected to computing device  100  through base connector  220  and carrier connector  120 , in the manner already described with respect to  FIG. 1 . In this configuration, carrier air outlet  115   b  is abutting base air inlet  215   a . Carrier fan  115  in computing device  100  draws air from the outside through carrier inlet  115   a  into air guide  115   c . The air is then expelled through carrier air outlet  115   b . As computer core  200  and computing device  100  are connected, the air expelled through carrier air outlet  115   b  is channeled into base air inlet  215   a  of computer core  200 . In computer core  200 , the air flows through the enclosure, over heat sink  215   f  and then exits through base air outlet  215   b . The flowing air is heated by the heat-dissipating components along the way. In one embodiment, unlike a conventional thermal module that blows air only on a heat sink, the air flow in computer core  200  also removes heat from GPU  201   g , CPU  201   c , heat plate  215   d , heat pipe  215   e , and any other component mounted on or attached to base board  250  before reaching heat sink  215   f  and base air outlet  215   b . In another embodiment, computer core  200  is akin to a sealed envelope, with heat sink  215   f  being located at the top end, so as to create a “chimney effect,” which helps to drive natural ventilation and ex-filtration. These effects cool down the components faster and reduce the energy required by the fan. Likewise, air guide  115   c  may include walls that guide the flow of air over selected components in computing device  100 . Computing device  100  may be itself a standalone device, such as a control unit having an external hard drive in data storage  160 , data I/O interfaces  113 , and display ports for connecting to external displays. Air guide  115   c  can guide the air to flow over the hard drive, and the display control unit. Such a device may have the power of a desktop computer when computer core  200  is connected. 
         [0028]      FIG. 3   a  which is a top view of one implementation of computer core  200  using an x86 processor and an ARM processor. As shown in  FIG. 3 , computer core  200  has a hybrid of an x86 processor base in computer module  255  (COM), and an ARM processor on base board  250 . In one embodiment, COM module  255  is a single circuit board x86-based computer with RAM, input/output controllers and other peripheral devices. COM module  255  includes module connector  256  that is to be connected with matched module connector  256  on base board  250 . Base board  250  includes an optional ARM cpu  252  microprocessor and optional components, such as RAM, a WIFI wireless device, a Bluetooth wireless device, a 3 G communication module, a camera, a USB hub controller, embedded controller  201   e , and numerous sensors. These components may be integrated with base board  250  directly without going through external peripheral connectors. COM module  255  may be mounted on base board  250  through module connector  256 , which may a proprietary or industrial standard COM Type connector (e.g., Type 10 connector). COM module  255  and components on base board  250  communicate with each other over the module connectors according to predefined functions defined on the connector pins. For example, if COM module connector  256  is a Type 10 connector, the optional components on base board  250  may communicate with COM module  255  through the USB pins or PCIe pins. Base board  250  may connect to carrier board  150  through base connector  220 , as shown in  FIG. 1 . 
         [0029]    In one embodiment, a user may select the x86-based microprocessor or the ARM microprocessor to boot computer core  200 . The user&#39;s selection may be made using an interface provided by boot program. In another embodiment, computer core  200  may make the selection automatically based on detecting the availability of carrier fan  115  on connected computing device  100 . For example, computer core  200  may boot by default from the x86-based microprocessor (as CPU  201   c ) if carrier fan  115  is detected on connected computing device  100 . Otherwise, the fan-less ARM microprocessor is selected, to reduce system&#39;s energy requirement and heat dissipation. In another embodiment, a user can switch from the higher power microprocessor to the lower power microprocessor in computer core  200  at run time through an application interface that allows user selection of which processor to use for energy saving and reduced heat generation. In another embodiment, instead of being provided on base board  250 , the ARM processor can be mounted on COM module with the x86-based processor. In anther embodiment, the ARM microprocessor can be integrated inside the x86-base microprocessor or chipset. Such a “hybrid” chipset (i.e., a chipset that makes available both an x86-based microprocessor and an ARM microprocessor) is available, for example, from Advanced Micro Devices, Inc. (AMD). 
         [0030]      FIG. 3   b  is a section view of the implementation of computer core  200  of  FIG. 3   a  along its length through connector  220 . When base board  250  is connected with carrier board  150  through base connector  220  and carrier connector  120 , air can flow from base air inlet  215   a  to base air outlet  215   b  (or vice versa) according to the air flow direction of carrier fan  115  in connected computing device  100 . The air flow cools heat plate  215   d , heat pipe  215   e , and heat sink  215   f  and other heat-dissipating components of computer core  200 . 
         [0031]      FIG. 4  is a block diagram showing one exemplary implementation of computing device  100  and computer core  200  being connected over a proprietary interface or an open interface, in accordance with one embodiment of the present invention. An open interface (e.g., the Portable Digital Media Interface (PDMI)) is typically an industry interconnection standard for portable media players. In one embodiment, computing device  100  includes a control unit  101 , which may be implemented by an embedded controller. Control unit  101  may carry out command execution, peripheral coordination, and information exchange with embedded controller  201   e  in computer core  200 . As shown in  FIG. 4 , computing device  100  includes (a) power supply  102 , which is connected to power jack  102   a  for supplying power to all components in computing device  100 , (b) data storage  160  (e.g., a USB data storage device), (c) USB hub  161 , which controls both devices and data ports, and (d) display control  162  for controlling display ports and external displays. Under the PDMI standard, for a male connector, carrier connector  120  includes pins for power interface  171 , data interface  172  (e.g., a USB data interface), and video interface  173  (e.g., HDMI). As shown in  FIG. 4 , computer core  200  includes (a) a power bus to distribute power to the components of computer core  200 , (b) data control unit  261  (e.g., a USB data control unit), and (c) display control unit  262 . For the female connector, under the PDMI standard, base connector  220  includes pins for (a) power interface  271 , (b) data interface  272  (e.g., a USB data interface), and (c) video interface  273  (e.g., a Display Port video interface). Computer core  200  may also implements x86-based microprocessor and chipset for CPU  201   c  and GPU  201   g  (e.g., an Intel Atom processor) with memories to run application programs. When computer core  200  and computing device  100  are connected through the PDMI connectors, power is supplied by computing device  100  to computer core  200 . Computer core  200  then boots its operating system, loads application programs and data from connected network servers, cloud servers, or data storage  160  through data control unit  262 , data interfaces  172  and  272 , and data hub  161 . Computer core  200  may provide video data to an external monitor connected to display port  180  through display control units  162  and  262 , and display interfaces  172  and  272 . The user may interact with computing device  100  and computer core  200 , using an external keyboard or a mouse (or both) connected to data port  181 . The data input from the user is sent to control unit  101  through data hub  161 , data interfaces  172  and  272 , and data control unit  261 . 
         [0032]    For thermal management, the higher power x86-based microprocessor in computer core  200  requires a thermal module (e.g., thermal module  215 ) for heat dissipation. As described above, thermal module  215  includes heat plate  215   d , heat pipe  215   e , and heat sink  215   f . In one embodiment, computer core  200  has heat plate  215   d  mounted over at least one of GPU  201   g , CPU  201   c , or other heat-dissipating components, and transfers the heat to heat pipe  215   e . Heat pipe  215   e  is connected to heat sink  215   f , which has a structure with a large surface area that is in contact with—and dissipates heat to—the surrounding air. In one embodiment, as described above, computer core  200  includes base air inlet  215   a  as an entry port to allow air to flow into its enclosure, and base air outlet  215   b  as an exit port for the heated air. As discussed above, computing device  100  includes carrier air inlet  115   a  as openings or slots in the enclosure wall or openings in the I/O connectors that allow air to enter into its enclosure, and has at least one carrier fan (e.g., carrier fan  115 ) to blow air into air guide  115   c . Air guide  115   c  has a pipe like structure to convey the air into carrier air outlet  115   b , and from there into computer core  200  through base air inlet  215   a  that has openings structurally matching those in carrier air outlet  115   b  when connected. Computer core  200  may include an optional second chipset  202  to implement CPU  201   c  and GPU  201   g  e.g., an embedded ARM microprocessor. Typically, the low-power microprocessor does not require thermal module  215  to dissipate heat. Base on computing needs, a user may choose at any given time the x86-based chip set or the low-power chipset at boot time, or switch to the low-power CPU at turn time to reduce heat dissipation and to provide better thermal management. 
         [0033]      FIG. 5  shows flowchart  500 , which illustrates system booting operations carried out by connected computing device  100  and computer core  200 , according to one embodiment of the present invention. In one embodiment, a user pushes a power button on computing device  100  (step  501 ), which triggers carrier embedded controller  101  to determine whether or not the system is already operating (step  502 ). If the system is already operating, carrier embedded controller  101  obtains from embedded controller  201   e  of computer core  200  state information regarding an optional battery (step  503 ). Otherwise, carrier embedded controller  101  determines if a security check is required (step  504 ). In one embodiment, when the optional battery is attached to the computer core  200 , carrier embedded controller  101  requests embedded controller  201   e  of computer core  200  to signal the CPU  201   c  to turn into a stand-by mode (step  505 ). However, if the optional battery is not present, carrier embedded controller  101  requests embedded controller  201   e  of computer core  200  to signal the CPU  201   c  to a hibernate or shut-down mode, depending on a default setting (step  507 ). In one embodiment, when security checking is determined in step  504  to be required, carrier embedded controller  101  requests embedded controller  201   e  of computer core  200  to perform the security check (step  507 ). In one embodiment, security checking may involve carrier embedded controller  101  executing one or more predefined algorithms (e.g., one involving an encryption key), or verifying or validating an RFID, a finger print, or a password. If the security checking is not required, or if the security check passes, embedded controller  201   e  of computer core  200  boots up the system (step  508 ). If the security check fails, the system suspends (i.e., the system does not boot up; step  509 ). 
         [0034]    In one embodiment, upon booting up (step  508 ), entering stand-by mode (step  506 ) or entering hibernate or shut down mode (step  506 ), carrier embedded controller  101  checks if a locking mechanism is available (step  510 ). If the locking mechanism is present, carrier embedded controller  101  requests a locking module to reverse computer core  200 &#39;s locked or unlocked state (step  511 ). Locking tightens the physical connection between computer core  200  and computing device  100 . Before the system boots up, the system is in the unlocked state. Therefore, after booting up the system, the system enters the locked state from the unlocked state. Conversely, upon entering the stand-by mode, the hibernate mode or the shut-down mode, the system also enters the unlocked state from the locked state. The locking module may include a mechanical or electric locker (e.g., a solenoid locker). If a locking mechanism is not available, the system remains in the same operation mode (step  509 ). 
         [0035]      FIG. 6  is a block diagram illustrating interactions between integrated computing device  100  and computer core  200  with external devices  300  and  400 , according to one embodiment of the present invention. In  FIG. 6 , computing device  100  is connected and provides power to computer core  200 . Computer core  200  is wirelessly connect to external device  400  (e.g., a smartphone, a notebook computer, or an augmented reality device). The wireless connection, for example, may be used to stream content to computer core  200  from external device  400  using a WiDi, Miracast, AirPlay, or a similar protocol. Computer core  200  and external device  400  may communicate using a Bluetooth or Wifi interface, for example. In one embodiment, for example, computer core  200  may accept wireless streaming of the content from external device  400  for display on display device  300 . Display device  200  (e.g., a graphical monitor or an HDTV unit) may be physically connected to computing device  100  through a display port or data port. In another embodiment, computer core  200  may accept streaming of content from external device  400  over a physical display port or data port connection between computer core  200  and external device  400  for display on display device  300 . In a third embodiment, computer core  200  may accept streaming of content from external device  400  over a physical display or data port connection between computing device  100  and external device  400  for display on display device  300 . In yet another embodiment, the computer core  200  may accept the streaming of content from the internet (e.g., a Youtube server) for display on display device  300 , which is physically connected to computing device  100  through a display port or data port. In yet another embodiment, computer core  200  displays its local content on display device  300 , which is physically connected to computing device  100  through a display port or data port. 
         [0036]      FIG. 7  is a sectional view of the chassis of computing device  100 , showing an antenna being placed thereon, according to one embodiment of the present invention. According to one embodiment, an antenna cable is directly connected to heat sink  215   f  of computing device  100 , so as to use heat sink  215   f  as an antenna, taking the advantage of heat sink  215   f &#39;s large surface area. A flexible antenna (e.g., a cable antenna) may be attached for signal reception on a wall of computer device  100 &#39;s chassis in the vicinity of heat sink  215   f . For example, the flexible antenna may be connected to antenna cable connector  231  on the chassis wall of computing device  100 . To avoid heat sink  215   f  interfering with the incoming or outgoing signals, the flexible antenna may be covered by antenna cover  232 , which may be formed out of an electrically insulating material. In another embodiment, a flexible antenna can be placed at a location that does not overlap heat sink  215   f  or where signal reception is not blocked or shielded by heat sink  215   f.    
         [0037]    The above detailed description is provided to illustrate the specific embodiments of the present invention and is not intended to be limiting. Numerous variations and modifications within the scope of the invention are possible. Having thus described the invention, what is desired to be protected by Letters Patent is presented in the subsequently appended claims.