Power delivery apparatus and method

The present invention provides a unitary integrated circuit and power supply module. In one embodiment, this module includes a bridging printed circuit board, an integrated circuit assembly, and a power conversion assembly. The integrated circuit assembly is operably mounted to the bridging printed circuit board. The power conversion assembly is also operably mounted to the bridging printed circuit board. Core power is provided to the integrated circuit assembly through the bridging printed circuit board from the power conversion assembly. In this way, detrimental parasitics are reduced through the elimination of a connector for coupling a power conversion module to an integrated circuit module.

DETAILED DESCRIPTION FIGS. 3A and 3B show top and bottom views, respectively, of one embodiment of a power conversion module 300 of the present invention. Power conversion module 300 generally includes power converter assembly 320 , edge connector 315 , and (as shown in FIG. 3B ) surface-mountable source connectors 325 , which advantageously have spring contacts 328 . Power converter assembly 320 comprises a power supply (or power conversion unit) for supplying power to an integrated circuit module (not shown). In one embodiment, power converter assembly 320 comprises a DC to DC down converting power supply for receiving and down converting a relatively high source voltage and providing to the integrated circuit module a relatively low-voltage (high current) supply. This high current supply is delivered to the integrated circuit module through edge connector 315 . Edge connector 315 couples this high-current supply to the integrated circuit module through a corresponding connector of the integrated circuit module. Edge connector 315 includes several conductors for supplying power to the integrated circuit module. In one embodiment, these conductors include high current capacity supply and return bars, along with one or more control lines such as voltage sense and switching lines. Instead of providing the source power to the power converter module through a pig tail (or similar) connection, one or more surface mountable source connectors 325 are used to provide power to module 300 directly from connection pads of a system assembly (e.g., a computer mother board). Thus, surface mountable source connector(s) 325 are operably mounted to the underside of power converter assembly 320 . This allows power converter module 300 to be more efficiently mounted into the mother board. It also allows power converter module 300 to move when mated to an integrated circuit module that is being “cinched ” into or released from its grid array connection. Furthermore, it eliminates the need for a corresponding, cooperative connector mounted to the mother board. That is, surface mountable connectors 325 “connect ” directly to pads on the mother board PCB. In the depicted embodiment, six connectors 325 —each having 4 contacts—are used to provide 28 surface mount contacts 328 . However, depending on factors (e.g., voltage, current, control signal requirements) relating to the supplied power source from the larger assembly, any suitable configuration could be used in this power converter module implementation. FIG. 4 shows a quasi block drawing of power conversion module 300 coupled to an integrated circuit module 460 through edge connector 315 . Along with power converter assembly 320 , edge connector 315 and source connector 325 , heat sink 445 , which is operably mounted to power converter assembly 320 , is also shown as part of the power converter module 300 . Additionally seen in this drawing, power converter assembly 320 includes power converter card 430 , power converter unit 435 mounted thereupon, and power output card 440 . Power converter unit (e.g., DC to DC down-converter) 435 appropriately converts the source power into the required supply power for powering integrated circuit module 460 . Power converter unit 435 receives the input source voltage through power converter card 430 , which is connected to source connector 325 . Power converter unit 435 is also connected to power output card 440 for providing it with the converted supply power. In turn, power output card 440 is connected to edge connector 315 for coupling the supply power to integrated circuit module 460 . As shown in FIG. 4 , integrated circuit module 460 generally includes integrated circuit signal connector 465 , integrated circuit PCB 480 , integrated circuit die 485 , and heat sink 495 . Integrated circuit die 485 is operably mounted to integrated circuit PCB (or daughter card) 480 . Integrated circuit signal connector 465 is also mounted to integrated circuit PCB 480 for providing integrated circuit die 485 with signal lines (and possibly relatively small power sources) from a mother board (not shown). Integrated circuit PCB 480 also has an appropriate edge card connection (hidden from view) for mating with edge connector 315 in order to receive core supply power from the power conversion module 300 . Finally, heat sink 495 is operably mounted to integrated circuit module 460 for conducting heat away from integrated circuit die 485 . Source power is coupled to power conversion module 300 through surface mountable source connector 325 . This is a substantial improvement over conventional pigtail or flying cable connections and allows power conversion module 300 to be more conveniently and efficiently mounted onto a mother board. In addition, it provides a “cleaner ” connection for providing source power from the mother board to power conversion module 300 . FIG. 5 shows one embodiment of an integrated circuit and power module 500 of the present invention. This module generally includes an integrated circuit assembly 510 with an associated integrated circuit signal connector 515 , a power conversion assembly 520 with an associated source connector 525 , and a bridging PCB 530 . Integrated circuit module portion 510 is mounted at one end of bridging PCB 530 ; while power conversion module portion 520 is mounted at its other end. In essence, bridging PCB 530 is used for transferring power from power conversion assembly 520 to integrated circuit assembly 510 . This eliminates the edge card connectors, which were previously used for coupling the power conversion module to the integrated circuit module. In this way, parasitic load resistance and inductance are significantly reduced for optimizing the power coupling to the integrated circuit assembly. Power conversion assembly 520 includes source connector 525 which, in the depicted embodiment, comprises a surface mountable PGA connector. Source connector 525 is utilized to couple source power from the mother board (not shown) to power conversion assembly 520 . Likewise, integrated circuit assembly includes integrated circuit signal connector 515 , which in the depicted embodiment is also a surface mountable PGA connector. Connector 515 is used to couple signal connections (and possibly small power source connections) to integrated circuit assembly 510 from the mother board (or other system assembly). In the depicted embodiment, bridging PCB 530 comprises a conventional multilayered (e.g., 17 layers) printed circuit board. Two of these layers are supply planes; two layers are used as return planes; and the remaining 13 layers are used as signal and impedance control planes. Most of the significant portions of the signal and impedance control layers will normally be associated with the integrated circuit and power conversion assemblies, 510 and 520 , respectively. That is, the exposed portion of bridging PCB 530 in the depicted drawing substantially corresponds to the supply and return planes of bridging PCB 530 . FIG. 6 , in a quasi-block diagram form, depicts integrated circuit and power conversion module 500 from FIG. 5 . As seen in FIG. 6 , power conversion assembly 520 includes power converter unit 635 mounted to bridging PCB 530 . It also includes an operably mounted heat sink 645 . Integrated circuit assembly 510 includes an integrated circuit die 685 , which is also mounted to bridging PCB 530 . Integrated circuit assembly 510 also includes its own operably mounted heat sink 695 . Single bridging PCB 530 is utilized for not only coupling power from power conversion assembly 520 to integrated circuit assembly 510 , but also, for separately interconnecting the various signals associated with each of these assemblies. Thus, bridging PCB 530 serves two fundamental roles. It provides PCB functionality for each of the integrated circuit and power conversion assemblies, and it provides a highly efficient power coupling from the power conversion assembly to the integrated circuit assembly. In the depicted embodiment, both the power conversion unit and power output functions are subsumed within power conversion unit 635 and mounted to bridging PCB 530 . However, a separate card(s) could be used for different parts of power conversion unit 635 so long as the power output section is mounted to bridging PCB 530 . With reference to FIG. 7 , the improved load characteristics of the integrated circuit assembly may be observed. As seen in this schematic, input inductance 11 has been reduced to 25 pH, and the input resistance R 1 has been reduced to 0.3 m′&OHgr;. This corresponds to an order of magnitude reduction in input parasitic impedance. With the input inductance being reduced to 25 pH, expected worse-case current fluctuations of 100 A per msec. will induce only 2.5 mV of noise a the integrated circuit assembly's input. This imposes an acceptably low frequency performance degradation of only 25 MHz. It should be recognized that while the integrated circuit and power conversion module in the depicted embodiment is implemented as two, discrete modules mounted to a common bridging PCB 530 persons of skill will recognize that numerous suitable alternatives may also be implemented. For example, the integrated circuit and power conversion portions could be mounted into a signal module for enhancing structural and heat transfer characteristics. In addition, in the depicted embodiment, a relatively long bridging PCB 530 is shown. As much as anything, this more readily conveys the general concept of using a PCB for coupling the modules. However, designers may wish to decrease the distance between the power conversion and integrated circuit portions in order to optimally reduce the coupling impedance parasitics. Specific optimal geometries and board layouts will depend upon the particular operational and design parameters of the associated integrated circuit and power conversion portions. Moreover, separate connectors have been used in the depicted embodiment for the integrated circuit and power conversion assemblies. However, single or multiple connectors could be used depending on specific design considerations. Along these lines, any suitable connector type could be used for supplying signals and source power to the integrated circuit and power conversion assemblies, respectively. Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.