Patent Publication Number: US-10782747-B2

Title: Adaptable storage bay for solid state drives

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. application Ser. No. 16/138,793, filed Sep. 21, 2018, now U.S. Pat. No. 10,359,815, which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to computer systems, and more particularly but not exclusively to storage devices. 
     2. Description of the Background Art 
     As is well known, a computer drive is a storage device used by computer systems. Solid state drives, such as those with integrated circuit (IC) non-volatile memory (e.g., non-volatile flash memory), are much faster than conventional electro-mechanical hard disk drives. Solid state drives with IC non-volatile memory are referred to herein as SSD modules. For example, the Non-Volatile Memory Express (NVME) specification provides for accessing solid state drives that are attached to a computer system by way of a Peripheral Controller Interconnect Express (PCIE) bus. 
     SSD modules that comply with the NVME specification are referred to herein as NVME modules. In computer systems that require large amounts of storage space, NVME modules may be installed in dedicated storage bays. For example, NVME modules may be mounted in corresponding storage trays, which are removably attached to a storage bay. Examples of storage bays for NVME modules include the SUPERMICRO® NVME platforms, which are commercially-available from Super Micro Computer, Inc. of San Jose, Calif. 
     SUMMARY 
     In one embodiment, a solid state drive (SSD) storage bay includes storage trays and connector cards. A storage tray has a an interposer and an SSD module. A connector of the interposer is connected to a connector of the SSD module, and another connector of the interposer is connected to a connector of a connector card. The connector card includes terminals that connect to a bus of a computer system. The interposer includes wirings that allow electrical signals to propagate between the two connectors of the interposer. The interposer includes circuitry that allow for voltage regulation of supply voltage, level shifting, and hot-swapping. 
     These and other features of the present invention will be readily apparent to persons of ordinary skill in the art upon reading the entirety of this disclosure, which includes the accompanying drawings and claims. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a partial perspective view of a storage bay in accordance with an embodiment of the present invention. 
         FIG. 2  shows a schematic diagram of the storage bay of  FIG. 1  as attached to a computer system in accordance with an embodiment of the present invention. 
         FIGS. 3 and 4  show a perspective view and an exploded view, respectively, of a storage tray in accordance with an embodiment of the present invention. 
         FIG. 5  shows a multi-view of the storage tray of  FIGS. 3 and 4  in accordance with an embodiment of the present invention. 
         FIG. 6  is a larger drawing of an edge view of  FIG. 5 . 
         FIG. 7  shows a top view of a plurality of storage trays in accordance with an embodiment of the present invention. 
         FIG. 8  shows an arrangement of an SSD module, an interposer, and a connector card in accordance with an embodiment of the present invention. 
         FIG. 9  shows an arrangement of an SSD module, an interposer, and a connector card in accordance with another embodiment of the present invention. 
         FIG. 10  shows a schematic diagram of an interposer in accordance with an embodiment of the present invention. 
     
    
    
     The use of the same reference label in different drawings indicates the same or like components. Drawings are not necessarily to scale unless otherwise noted. 
     DETAILED DESCRIPTION 
     In the present disclosure, numerous specific details are provided, such as examples of systems, components, and methods, to provide a thorough understanding of embodiments of the invention. Persons of ordinary skill in the art will recognize, however, that the invention can be practiced without one or more of the specific details. In other instances, well-known details are not shown or described to avoid obscuring aspects of the invention. 
       FIG. 1  shows a partial perspective view of a storage bay  100  in accordance with an embodiment of the present invention. In the example of  FIG. 1 , the storage bay  100  includes a chassis (not shown) that allows the storage bay  100  to be mounted on an equipment rack along with other storage bays. The storage bay  100  may include a plurality of connector cards  110  and a plurality of storage trays  150 ,  130 . Only some of the connector cards  110  and corresponding bay connectors  112  are labeled in  FIG. 1  for clarity of illustration. The storage trays  150 ,  130  are in so-called vertical mounting configuration relative to a horizontally-mounted motherboard  114  (see also  FIGS. 2, 8 , and  9 ), which may comprise a printed circuit board (PCB). In the present disclosure, “horizontal” and “vertical” are relative to the floor of the computer room in which the storage bay  100  is deployed. 
       FIG. 2  shows a schematic diagram of the storage bay  100  as attached to a computer system  190  in accordance with an embodiment of the present invention. Generally speaking, a connector card  110  is configured to allow a storage tray  150  or  130  to be mechanically and electrically connected to a computer bus  191  of the computer system  190 . Only the storage tray  150  is shown in  FIG. 2  for clarity of illustration. In the example of  FIG. 2 , the computer system  190  includes one or more processors  192 , main memory  193  (e.g., random-access memory), and other components. The computer system  190  is commercially-available from various computer vendors, such as Super Micro Computer, Inc. of San Jose, Calif. 
     A connector card  110  comprises a bay connector  112  and an array of bay terminals  113  (see also  FIGS. 8 and 9 ). The bay connector  112  is configured to removably mate with a tray connector  171 ,  131  of a corresponding storage tray  150 ,  130 . In one embodiment, the bay connector  112  is a slot-type connector, which is configured to receive an edge-type tray connector  171 ,  131 . The bay terminals (e.g., pins)  113  of a connector card  110  are configured to be connected to the computer bus  191 . In one embodiment, the bay terminals  113  are configured to be fixedly connected (e.g., soldered) to corresponding pins of a PCIE bus on the motherboard  114 . The bay terminals  113  may also be part of a PCIE connector that is removably connected to a corresponding PCIE connector on the motherboard  114 . 
     Referring back to the example of  FIG. 1 , a storage tray  150 ,  130  comprises an SSD module, which in one embodiment is an NVME module. Generally speaking, a particular computer vendor expects a storage tray to comply with certain mechanical and electrical requirements to be compatible with that vendor&#39;s storage bays. Deviating from the requirements prevents a storage tray from being installed in the storage bay of that particular computer vendor. 
     In the example of  FIG. 1 , the storage tray  130  is a conventional storage tray. Some storage trays  130  may comply with the so-called Next-generation Small Form Factor (NGSFF) specification promulgated by the Samsung™ company. In such storage trays  130 , the tray connector  131  is an NGSFF connector. Other storage trays  130  may comply with the so-called Enterprise and Data Center Solid State Drive Form Factor (EDSFF) specification promulgated by the Intel™ corporation and other computer vendors. In that case, the tray connector  131  is an EDSFF connector. 
     A problem with conventional storage trays is that the NGSFF and ESDFF specifications are not mechanically and electrically compatible with each other. In other words, a storage tray  130  that complies with the NGSFF specification cannot be installed in a storage bay that complies with the EDSFF specification, and vice versa. More particularly, the NGSFF and ESDFF specifications require different connector types, pinouts, etc. Therefore, for cost and compatibility reasons, an enterprise customer has to commit to, and thus be limited by, a particular form factor specification. Another problem with conventional storage trays is that they do not provide adequate thermal management, which may result in heat build-up in storage bays that contain several storage trays. 
       FIGS. 3 and 4  show a perspective view and an exploded view, respectively, of the storage tray  150  in accordance with an embodiment of the present invention. As shown in  FIGS. 3 and 4 , the storage tray  150  may comprise a frame  151 , an SSD module  120 , and an interposer  170 . These features of the storage tray  150  are also labeled in  FIG. 1  for orientation purposes. 
     Referring first to the perspective view of  FIG. 3 , the frame  151  may comprise a plate  157  to which the SSD module  120  and the interposer  170  are mounted. The SSD module  120  may be fastened to the plate  157  by a screw  162 , and the interposer  170  may be fastened to the plate  157  by a screw  158 . Standoffs (see  FIGS. 4, 159 and 161 ) between the plate  157  and the SSD module  120  and interposer  170  allow for directed air-flow through the storage tray  150 . An ejector  160  provides a lever that facilitates insertion and removal of the storage tray  150  into and out of the storage bay  100 . The ejector  160  is rotatably attached to a point on the frame  151 , and may be actuated by swinging the ejector  160 . 
     To install the storage tray  150  into the storage bay  100 , the tray connector  171  is inserted into a bay connector  112  of a corresponding connector card  110 . This mechanically connects the terminals of the tray connector  171  to the terminals of the bay connector  112 , thereby establishing an electrical connection between components of the SSD module  120  and the computer system  190  by way of the computer bus  191  (see  FIG. 2 ). In this example where the SSD module  120  is an NVME module, the computer system  190  communicates with the SSD module  120  in accordance with the NVME specification. 
     For ease of illustration, components previously described with reference to  FIG. 3  are also labeled in the exploded view of  FIG. 4 . As shown in  FIG. 4 , the plate  157  may have a raised portion  156  that has a plurality of mounting holes  153 - 155 . This configuration allows the frame  151  to accommodate different sizes of SSD modules  120 . More particularly, a standoff  161  may be attached to one of the mounting holes  153 - 155  to secure an SSD module  120  of a particular size. A notch  122  (e.g., on the circuit board) of an SSD module  120  may be secured between the standoff  161  and the screw  162 . A corresponding screw  165  may be used to fasten the standoff  161  into the mounting hole  153 , or other mounting hole depending on the dimensions of the SSD module  120 . The SSD module  120  includes an edge-type connector  121 , which is removably inserted into a slot-type connector  172  of the interposer  170 . In one embodiment, the SSD module  120  is an NVME module that is compliant with the M.2 form factor specification. Accordingly, the connector  121  may be an M.2 connector. Generally speaking, the M.2 form factor specification allows SSD modules to have widths of 12 mm, 16 mm, 22 mm, and 30 mm, and lengths of 16 mm, 26 mm, 30 mm, 38 mm, 42 mm, 60 mm, 80 mm, and 110 mm. For illustration purposes only, the example of  FIG. 4  shows an SSD module  120  with dimensions of 22 mm×80 mm (width×length), having a notch  122  that is secured to the standoff  161 , which is mounted on the mounting hole  153 . In one embodiment, an SSD module  120  is a commercially-available SSD module that complies with the NVME and M.2 specifications. 
     In one embodiment, the interposer  170  comprises a circuit card  173  (e.g., PCB), the connector  172 , and the tray connector  171 . The connector  172  is mounted on the circuit  173  on a vertical edge of the circuit card  173 , and the tray connector  171  is mounted on an opposing vertical edge of the circuit card  173 . The connector  121  of the SSD module  120  is removably connected to the connector  172 , and the tray connector  171  is removably connected to a corresponding bay connector  112  of a connector card  110 . The circuit card  173  includes wiring connections that allow electrical signals from the terminals of the connector  172  to be coupled to corresponding terminals of the tray connector  171 . 
     In the example of  FIG. 4 , the circuit card  173  includes a mounting hole  175  on a horizontal edge and a mounting tab  174  on an opposing horizontal edge. To mount the interposer  170  to the frame  151 , the mounting tab  174  is inserted into a slot  163  of the frame  151 , and the mounting hole  175  is secured between the screw  158  and the standoff  159 . The mounting tab  174  and the slot  163  allow for relatively easy and secure alignment of the interposer  170  using only a single screw on only one horizontal edge of the circuit board  173 . In the example of  FIG. 4 , the plate  157  has a plurality of vent holes  164  directly underneath the plane of the interposer  170 . The vent holes  164  serve as a cooling vent that allows cooling air to flow through a gap between the plate  157  and the undersides of the SSD module  120  and the interposer  170 . A plurality of mounting holes  176  on the plate  157  allow electromagnetic interference (EMI) springs  180  (see  FIGS. 5 and 6 ) to be mounted on the plate  157 . 
       FIG. 5  shows a multi-view of the storage tray  150  in accordance with an embodiment of the present invention.  FIG. 5  shows a top view  301 , a side view  302 , and an edge view  303 . The top view  301  and the edge view  303  show EMI springs  180 , which as noted may be installed to the storage tray  150  on the mounting holes  176  (see  FIG. 4 ). The components labeled in  FIG. 5  have been previously described with reference to  FIGS. 3 and 4 , and are noted in  FIG. 5  for orientation purposes. 
       FIG. 6  is a larger drawing of the edge view  303  of  FIG. 5 . As shown in  FIG. 6 , the plane of the circuit card  173  of the interposer  170  is in parallel with the plane of the plate  157 , with a gap  201  between them. The standoff  159  and the tab  174 /slot  163  configuration raise the circuit card  173  away from the plate  157  to form the gap  201 . The vent holes  164  (see  FIG. 4 ) on the plate  157  allows air from the cooling unit (e.g., fans) of the storage bay  100  to flow in the gap  201  and thereby cool the components of the storage tray  150 . The cooling air exits from the gap  201  to cool other storage trays installed in the storage bay  100 . The EMI springs  180  compress to allow relatively tight electrical contact with an adjacent storage tray  150  to minimize or prevent electromagnetic/radio frequency interference (RFI) in the storage bay  100 . 
       FIG. 7  shows a top view of a plurality of storage trays  150  in accordance with an embodiment of the present invention.  FIG. 7  shows the relative positions of adjacent storage trays  150  as installed in the storage bay  100 . When a plurality of storage trays  150  are installed in the storage bay  100 , an EMI spring  180  of one storage tray  150  makes an electrical connection with a frame  151  (or other shield point) of an adjacent storage tray  150  to maintain EMI/RFI shielding. 
       FIG. 8  shows an arrangement of an SSD module  120 , an interposer  170 A, and a connector card  110 A in accordance with an embodiment of the present invention. The interposer  170 A is a particular implementation of the interposer  170 . As before, the interposer  170 A and the SSD module  120  are mounted as part of a storage tray  150 . An M.2 connector  121  of the SSD module  120  is removably connected to the connector  172  of the interposer  170 A. In the example of  FIG. 8 , the interposer  170 A includes an edge-type tray connector  171 A that is compliant with the NGSFF specification. The circuit card  173 A is a particular implementation of the circuit card  173 . In the example of  FIG. 8 , the circuit card  173 A of the interposer  170 A provides wiring connections that allow electrical signals from the terminals of the connector  172  to be coupled to corresponding terminals of the tray connector  171 A in compliance with the NGSFF specification. Also labeled in  FIG. 8  are the tab  174 A and mounting hole  175 A of the circuit card  173 A. 
     In the example of  FIG. 8 , the connector card  110 A is a particular implementation of the connector card  110 . The connector card  110 A has a slot-type bay connector  112 A that is configured to removably mate with the tray connector  171 A of the interposer  170 A. The bay connector  112 A is compliant with the NGSFF specification. The bay terminals  113  of the connector card  110 A may comprise pins that are electrically connected to a PCIE bus on the motherboard  114 . The storage tray  150  is thus adaptable to allow an NVME module that is compliant with the M.2 form factor specification to connect to an NGSFF-compliant storage bay  100 . 
       FIG. 9  shows an arrangement of an SSD module  120 , an interposer  170 B, and a connector card  110 B in accordance with another embodiment of the present invention. The interposer  170 B is a particular implementation of the interposer  170 . As before, the interposer  170 B and the SSD module  120  are mounted as part of a storage tray  150 . An M.2 connector  121  of the SSD module  120  is removably connected to the connector  172  of the interposer  170 B. In the example of  FIG. 9 , the interposer  170 B includes an edge-type tray connector  171 B that is compliant with the EDSFF specification. The circuit card  173 B is a particular implementation of the circuit card  173 . In the example of  FIG. 9 , the circuit card  173 B of the interposer  170 B provides wiring connections that allow electrical signals from the terminals of the connector  172  to be coupled to corresponding terminals of the tray connector  171 B in compliance with the EDSFF specification. Also labeled in  FIG. 9  are the tab  174 B and mounting hole  175 B of the circuit card  173 B. 
     In the example of  FIG. 9 , the connector card  110 B is a particular implementation of the connector card  110 . The connector card  110 B has a slot-type bay connector  112 B that is configured to removably mate with the tray connector  171 B. The bay connector  112 B is compliant with the EDSFF specification. The bay terminals  113  of the connector card  110 B may comprise pins that are electrically connected to a PCIE bus on the motherboard  114 . The storage tray  150  is thus adaptable to allow an NVME module that is compliant with the M.2 form factor specification to connect to an EDSFF-compliant storage bay  100 . 
       FIG. 10  shows a schematic diagram of an interposer  170  in accordance with an embodiment of the present invention. As previously noted, an interposer  170  may include a connector  172  that is removably connected to a connector  121  of an SSD module  120 , and a tray connector  171  that is removably connected to a bay connector  112  of a connector card  110 . 
     In the example of  FIG. 10 , the SSD module  120  is an NVME module that is compliant with the M.2 form factor specification. In one embodiment, the interposer  170  comprises wirings (e.g., PCB traces) that directly connect PCIE bus signal pins  310  of the SSD module  120  to corresponding PCIE bus signal pins  360  of the connector card  110 . The SSD module  120  further includes provisions for connecting System Management Bus (SMB) signal (e.g., clock, data) pins  320  to corresponding SMB signal pins  370  of the connector card  110 . In the example of  FIG. 10 , the interposer  170  includes a level shifter circuit  306  that is configured to translate the logic levels of SMB signals for compatibility between the SSD module  120  and the connector card  110 . 
     In the example of  FIG. 10 , the interposer  170  includes wirings that directly connect ground reference pins  322  of the connector  121  of the SSD module  120  to ground reference pins  380  of the bay connector  112  of the connector card  110 . The interposer  170  further includes a voltage regulator  307  that is configured to receive supply voltage from the supply voltage pins  381  of the bay connector  112  of the connector card  110 , and to provide supply voltage to the supply voltage pins  321  of the connector  121  of the SSD module  120 . In one embodiment, the voltage regulator  307  is a step-down voltage regulator. As a particular example, the voltage regulator  307  may be configured to lower a 12V supply voltage received from the connector card  110  to 3.3V, which is provided to the SSD module  120 . 
     In one embodiment, the interposer  170  further includes a hot-swap circuit  308 , which is configured to allow the SSD module  120  to be hot-swappable to the connector card  110 . More particularly, the hot-swap circuit  308  allows an SSD module  120  that is compliant with the M.2 form factor specification, which is not hot-swappable, to be inserted and removed from the connector card  110  while power is provided on the supply voltage pins  381 , i.e., while the storage bay  100  remains powered up. In one embodiment, the hot-swap circuit  308  is electrically connected to one or more presence pins  390  on the bay connector  112  of the connector card  110 . Any suitable discrete or integrated circuit hot-swap circuit may be employed without detracting from the merits of the present invention. 
     As can be appreciated from the foregoing, the connections shown in  FIG. 10  may be modified depending on the connector card  110 . For example, when the connector card  110  is an NGSFF connector card (e.g.,  FIG. 8, 110A ), the SMB alert pin of the SSD module  120  for indicating to the computer system  190  that the SMB requires attention would be connected to a corresponding SMB alert pin on the connector card  110 , as in  FIG. 10 . However, when the connector card  110  is an EDSFF connector card (e.g.,  FIG. 9, 110B ), the SMB alert pin of the SSD module  120  is left as an open trace, i.e., not connected. 
     Embodiments of the present invention provide many advantages heretofore unrealized. First, embodiments of the present invention allow an SSD storage bay to receive SSD modules that are compliant with different specifications, thereby reducing the cost of operating and maintaining an enterprise computer system. Second, embodiments of the present invention allow SSD modules to have hot-swap capability. Third, embodiments of the present invention allow SSD storage bays to have adequate cooling even with several storage trays installed. 
     Adaptable SSD storage bays and associated components have been disclosed. While specific embodiments of the present invention have been provided, it is to be understood that these embodiments are for illustration purposes and not limiting. Many additional embodiments will be apparent to persons of ordinary skill in the art reading this disclosure.