Abstract:
A method for distributing power in an electronic system comprising of receiving power in a first domain at a connector of a peripheral device and converting the power to a second domain at the connector of the peripheral device is disclosed.

Description:
FIELD OF THE INVENTION 
     The present invention relates to the field of power distribution in computer systems. More specifically, the present invention relates to an alternating current (AC) and a direct current (DC) power distribution system. 
     BACKGROUND OF THE INVENTION 
     One known approach used for distributing power from a power source to components on a computer system is the direct current (DC) power distribution system. The DC power distribution system typically includes a main power supply, voltage regulator modules, and connectors that couple the main power supply to the voltage regulator modules. The main power supply converts low frequency (approximately 50-60 Hz) AC power received from the power source into DC power. The main power supply then converts the DC power into high frequency AC power. The high frequency AC power is then stepped down, converted back to DC power, and filtered before being transmitted along a connector to a voltage regulator module corresponding to a component on the computer system. At the voltage regulator module (VRM), the DC power is converted to AC power, stepped down, converted to DC power and filtered before being delivered to a component on the computer system. 
     A drawback of the DC distribution system was that it imposed dual conversion on the power conversion chain. Dual power conversion added complexity as well as cost and parts-count to the distribution system. Furthermore, the dual power conversion reduced the efficiency of the distribution system. In addition, today&#39;s computer systems are being designed with more stringent power specifications. These specifications require increased slew rates (change of current over time). Current DC distribution systems have experienced difficulties in reliably supporting these requirements. 
     Additionally, each VRM includes a controller monitor and regulates power output. Since each VRM has its own controller, the system does not have a centralized controller to regulate output power further adding complexity and circuitry. Another drawback of the known approach is that power to the processor is static and does not vary depending upon the power needs of the processor. 
     One solution to the drawbacks of the DC distribution system is a high-frequency alternating current (HFAC) distribution system. An advantage of HFAC distribution system includes no need for dual power conversion on the power conversion chain, thereby, reducing the complexity as well as cost and parts-count to the distribution system. Another advantage of HFAC power distribution system includes, increased efficiency of the distribution system in today&#39;s computer systems being designed with more stringent power specifications, specifically, slew rates (change of current over time) are increased. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings, in which the like references indicate similar elements and in which: 
     FIG. 1 illustrates a computer system  100  upon which an embodiment of the present invention can be implemented; 
     FIG. 2 illustrates peripheral devices of a computer system connected together in a hub topology and powered by the system power supply incorporating an embodiment of the present invention; 
     FIG. 3 illustrates peripheral devices of a computer system connected together in a daisy-chain topology and powered by the system power supply incorporating an embodiment of the present invention; 
     FIG. 4 illustrates a detailed view of a connector and a peripheral device in accordance with an embodiment of the present invention; 
     FIG. 5 is a block diagram of one embodiment of the connector shown in FIG. 4 according to the teachings of the present invention; 
     FIG. 6 illustrates a detailed view of connector and a peripheral device in accordance with an alternate embodiment of the present invention; 
     FIG. 7 is a block diagram of one alternate embodiment of the connector shown in FIG. 6 according to the teachings of the present invention; and 
     FIG. 8 is flow chart illustrating a method for converting power signals at connectors according to an embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION 
     In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, those skilled in the art will understand that the present invention may be practiced without these specific details, that the present invention is not limited to the depicted embodiments, and that the present invention may be practiced in a variety of alternate embodiments. In other instances, well known methods, procedures, components, and circuits have not been described in detail. 
     Parts of the description will be presented using terminology commonly employed by those skilled in the art to convey the substance of their work to others skilled in the art. 
     Various operations will be described as multiple discrete steps performed in turn in a manner that is helpful in understanding the present invention. However, the order of description should not be construed as to imply that these operations are necessarily performed in the order they are presented, or even order dependent. Lastly, repeated usage of the phrase “in one embodiment” does not necessarily refer to the same embodiment, although it may. 
     As technology moves toward utilization of HFAC power distribution, DC power distribution in computer systems is likely to become obsolete. The vast majority of existing computer systems, and computer systems sold in the near future, however, will likely continue to use DC power distribution. In order to promote HFAC market penetration, a need exists to support both HFAC and DC power distribution. 
     The present invention provides power connectors that allow DC and HFAC power distribution peripheral devices to be used in the same computer system. 
     FIG. 1 illustrates a computer system  100  upon which an embodiment of the present invention can be implemented. The computer system  100  includes a processor  101  that processes data signals. The processor  101  may be a complex instruction set computer (CISC) microprocessor, a reduced instruction set computing (RISC) microprocessor, a very long instruction word (VLIW) microprocessor, a processor implementing a combination of instruction sets, or other processor device. FIG. 1 shows an example of the present invention implemented on a single processor computer system  100 . However, it is understood that the present invention may be implemented in a computer system having multiple processors. The processor  101  is coupled to a CPU bus  110  that transmits data signals between processor  101  and other components in the computer system  100 . 
     The computer system  100  includes a memory  113 . The memory  113  may be a dynamic random access memory (DRAM) device, a synchronous direct random access memory (SDRAM) device, or other memory device. The memory  113  may store instructions and code represented by data signals that may be executed by the processor  101 . 
     A bridge/memory controller  111  is coupled to the CPU bus  110  and the memory  113 . The bridge/memory controller  111  directs data signals between the processor  101 , the memory  113 , and other components in the computer system  100  and bridges the data signals between the CPU bus  110 , the memory  113 , and a first I/O bus  120 . 
     The first I/O bus  120  may be a single bus or a combination of multiple buses. As an example, the first I/O bus  120  may comprise a Peripheral Component Interconnect (PCI) bus, a Personal Computer Memory Card International Association (PCMCIA) bus, a NuBus, or other buses. The first I/O bus  120  provides communication links between components in the computer system  100 . A network controller  121  is coupled to the first I/O bus  120 . The network controller  121  links the computer system  100  to a network of computers (not shown in FIG. 1) and supports communication among the machines. A display device controller  122  is coupled to the first I/O bus  120 . The display device controller  122  allows coupling of a display device (not shown) to the computer system  100  and acts as an interface between the display device and the computer system  100 . The display device controller  122  may be a monochrome display adapter (MDA) card, a color graphics adapter (CGA) card, an enhanced graphics adapter (EGA) card, an extended graphics array (XGA) card or other display device controller. The display device (not shown) may be a television set, a computer monitor, a flat panel display or other display device. The display device receives data signals from the processor  101  through the display device controller  122  and displays the information and data signals to the user of the computer system  100 . 
     A second I/O bus  130  may be a single bus or a combination of multiple buses. As an example, the second I/O bus  130  may comprise a PCI bus, a PCMCIA bus, a NuBus, an Industry Standard Architecture (ISA) bus, or other buses. The second I/O bus  130  provides communication links between components in the computer system  100 . A data storage device  131  is coupled to the second I/O bus  130 . The data storage device  131  may be a hard disk drive, a floppy disk drive, a CD-ROM device, a flash memory device or other mass storage device. A keyboard interface  132  is coupled to the second I/O bus  130 . The keyboard interface  132  may be a keyboard controller or other keyboard interface. The keyboard interface  132  may be a dedicated device or can reside in another device such as a bus controller or other controller. The keyboard interface  132  allows coupling of a keyboard (not shown) to the computer system  100  and transmits data signals from a keyboard to the computer system  100 . An audio controller  133  is coupled to the second I/O bus  130 . The audio controller  133  operates to coordinate the recording and playing of sounds. 
     A bus bridge  124  couples the first  110  bus  120  to the second I/O bus  130 . The bus bridge  124  operates to buffer and bridge data signals between the first I/O bus  120  and the second I/O bus  130 . 
     The computer system  100  includes a system power supply  150 . The system power supply  150  receives power from a power source such as a wall socket (not shown) or other power source. The system power supply  150  can supply power to various peripheral devices in the computer system  100 . For instance, in the illustrated embodiment, the system power supply  150  connects to the processor through a connector  160 . According to the teachings of the present invention, the type of connector  160  will depend upon the type of power signal provided by the system power supply  150  and the type of power signal required by the computer system  100 . 
     FIG. 2 illustrates peripheral devices of a computer system connected together in a hub topology and powered by the system power supply. In FIG. 2, the system power supply  150  provides power signals to a number of peripheral devices  221 - 226  through several power signal lines  231 - 236  in the hub topology. According to the teachings of the present invention, the power signal lines  231 - 236  provide power signals to the peripheral devices  221 - 226  through inventive connectors  241 - 246 . The peripheral devices  221 - 226  may require high-frequency alternating current (HFAC) power signals or traditional direct current (DC) power signals. Additionally, the power supply  150  may provide HFAC or traditional DC power signals. It should be appreciated that the connectors  241 - 246  will allow the use of both HFAC and traditional DC power signals for the peripherals  221 - 226  consistent with the present invention. Furthermore, shown in FIG. 2, the peripheral devices include a modem  221 , a display device  222 , a scanner device  223 , digital video disk (DVD) device  224 , a compact disk rewritable (CD-RW) drive  225 , and a hard disk drive  226 , however, it should be appreciated that the peripheral devices may include any other type of peripheral devices known in the art. 
     FIG. 3 illustrates peripheral devices of a computer system connected together in a daisy-chain topology and powered by the system power supply incorporating an embodiment of the present invention. In FIG. 3, through a single power signal line  331 , the system power supply  150  provides power signals to the number of peripheral devices  221 - 226  in the daisy-chain topology. In FIG. 3, through a single line  331 , the peripheral devices  221 - 226  receive power signals from the system power supply  150 . Incorporating an embodiment of the present invention, the power signal line  331  provides power signals to the peripheral devices  221 - 226  through connectors  341 - 346 . The daisy-chain topology requires the connectors  341 - 346  to be connected to each other through lines  332 - 336 . Similarly, the peripheral devices  221 - 226  may require high-frequency alternating current (HFAC) power signals or traditional direct current (DC) power signals. Additionally, the power supply  150  may provide HFAC or traditional DC power signals. It should be appreciated that the connectors  341 - 346  will allow the use of both HFAC and traditional DC power signals for the peripherals  221 - 226  consistent with the present invention. Furthermore, shown in FIG. 3, the peripheral devices include a modem  221 , a display device  222 , a scanner device  223 , digital video disk (DVD) device  224 , a compact disk rewritable (CD-RW) drive  225 , and a hard disk drive  226 , however, it should be appreciated that the peripheral devices may include any other type of peripheral devices known in the art. 
     FIG. 4 illustrates a detailed view of a connector and a peripheral device in accordance with an embodiment of the present invention. Shown in FIG. 4, a peripheral device  440  requires a traditional DC power signal, and the peripheral device  440  has a connection point  430  configured to accept the traditional DC power signal. In accordance with the present invention, the connector  410  is configured to connect with the peripheral device  440  through a connection point  450 . In FIG. 4, the system power supply connection side  420  of the connector  410  is shown configured to accept a HFAC power signal from the system power supply  150 . The one embodiment of the present invention shown in FIG. 4 permits the system power supply  150  to provide HFAC power signal to the connector  410  through the system power supply connection side  420  of the connector  410 , and the connector  410  converts the HFAC power signal to the traditional DC power signal for the peripheral device  440 . The traditional DC power signal is provided to the peripheral device  440  through the connection point  450  on the connector  410  and the connection point  430  on the peripheral device. 
     Shown in FIG. 4, the illustrated embodiment of the present invention permits the system power supply  150  to provide HFAC power signal to the peripheral device  440  utilizing traditional DC power signal with the conversion from HFAC power signal to traditional DC power signal performed in the connector  410 . Thus, it will be appreciated by those skilled in the art that the present invention allows the provision of one type of power signal for a peripheral device that requires a different type of power signal. Additionally, it should be appreciated that the connector  410  shown in FIG. 4 can be used in several different embodiments, such as those shown in FIGS. 1,  2 , and  3 . 
     FIG. 5 is a block diagram of one embodiment of the connector shown in FIG. 4 according to the teachings of the present invention. In FIG. 5, a HFAC power signal is received at the system power supply connection side  420  of the connector  410 . Shown in FIG. 5, a rectifier unit  510  receives the HFAC power signal from the system power supply  150  and converts the signal component of the HFAC power into an output power signal in the traditional DC domain. In an alternate embodiment, a step down transformer (not shown) may be included as part of the rectifier unit  510  to step down the HFAC power signal to a lower power level. 
     Additionally, shown in FIG. 5, a filtering unit  520  is coupled to the rectifier unit  510 . The filtering unit  520  receives the DC power signal from the rectifier unit  510  and filters away ripple from the traditional DC power signal before transmitting the power signal to the connection point  450  on the connector  410 . 
     The system power supply connection side  420 , rectifier unit  510 , filtering unit  520 , and the connection point  450  may be implemented using any known circuitry technique. According to an embodiment of the present invention, the rectifier unit  510  and the filtering unit  520  may all reside on a single semiconductor substrate, be discrete components, or be a combination of both. 
     The connector  410  allows the use of HFAC power signal from the system power supply  150  by a peripheral device  440  requiring traditional DC power signal in accordance with the present invention. 
     FIG. 6 illustrates a detailed view of a connector and a peripheral device in accordance with an alternate embodiment of the present invention. Shown in FIG. 6, a peripheral device  640  requires HFAC power signal, and the peripheral device  640  has a connection point  630  configured to accept the HFAC power signal. In accordance with the present invention, the connector  610  is configured to connect with the peripheral device  640  through a connection point  650 . In FIG. 6, the system power supply connection side  620  of the connector  610  is shown configured to accept a traditional DC power signal from the system power supply  150 . The embodiment of the present invention shown in FIG. 6 permits the system power supply  150  to provide traditional DC power signal to the connector  610  through the system power supply connection side  620  of the connector  610 , and the connector  610  converts the traditional DC power signal to the HFAC power signal for the peripheral device  640 . The HFAC power signal is provided to the peripheral device  640  through the connection point  650  on the connector  610  and the connection point  630  on the peripheral device. 
     Shown in FIG. 6, the illustrated embodiment of the present invention permits the system power supply  150  to provide traditional DC power signal to the peripheral device  640  utilizing HFAC power signal with the conversion from traditional DC power signal to HFAC power signal performed in the connector  610 . Thus, it will be appreciated by those skilled in the art that the present invention allows the provision of one type of power signal for a peripheral device that requires a different type of power signal. Additionally, it should be appreciated that the connector  610  shown in FIG. 6 can be used in several different embodiments, such as those in FIGS. 1,  2 , and  3 . 
     FIG. 7 is a block diagram of one embodiment of the connector shown in FIG. 6 according to the teachings of the present invention. In FIG. 7, a traditional DC power signal is received that the system power supply connection side  620  of the connector  610 . Shown in FIG. 7, a first filter unit  710  receives the traditional DC power signal and reduces ripple in the traditional DC power signal preventing the transmission of noise generated by the system power supply  150 . A switching unit  715  is coupled to the first filter unit  710 , and the switching unit  715  receives the traditional DC power signal from the filtering unit  710  and converts the traditional DC power signal to HFAC power signal. 
     In FIG. 7, a second filtering unit  720  is coupled to the switching unit  715 . The second filtering unit  720  receives the HFAC power signal from the switching unit  715  and filters away ripple from the HFAC power signal. Additionally, shown in FIG. 7, a transformer unit  725  is coupled to the second filtering unit  720 . The transformer unit  725  receives the HFAC power signal from the second filtering unit  720  and steps the HFAC power signal down to a lower level before transmitting the HFAC power signal to the connection point  650  on the connector  610 . 
     The system power supply connection side  620 , first filtering unit  710 , switching unit  715 , second filtering unit  720 , transformer  725 , and the connection point  650  may be implemented using any known circuitry technique. According to an embodiment of the present invention, the first filtering unit  710 , switching unit  715 , second filtering unit  720 , and the transformer  725  may all reside on a single semiconductor substrate, be discrete components, or be a combination of both. 
     The connector  610  allows the use of traditional DC power signal from the system power supply  150  by a peripheral device  640  requiring HFAC power signal in accordance with the present invention. 
     FIG. 8 is flow chart illustrating a method for converting power signals at connectors according to an embodiment of the present invention. Power signal in one domain is received from a system power supply at a connector of a peripheral device  810 . The connector converts the power in the first domain to a second domain to meet the requirements of the peripheral device  820 . The power signal in the second domain is transmitted to the peripheral device  830 . 
     Thus, a method and apparatus for utilizing two different domain power signals is described. 
     In the forgoing description, the invention is described with reference to specific exemplary embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the present invention as set forth in the appended claims. The specifications and drawings are accordingly to be regarded in an illustrative rather than in a restrictive sense.