Information processing apparatus

Abstract

The present application provides an information processing apparatus capable of stably supplying a voltage to a removable storage device. The information processing apparatus of the present application includes a holding portion capable of holding the removable storage device, and a power supply circuit configured to supply a first voltage and a second voltage different from the first voltage to the removable storage device. The power supply circuit includes a plurality of feedback lines. A first feedback line of the plurality of feedback lines is electrically connected to one of a plurality of first power supply terminals capable of being supplied with the first voltage via the holding portion. A second feedback line of the plurality of feedback lines is electrically connected to one of a plurality of power supply ground terminals capable of being connected to a ground voltage via the holding portion. The power supply circuit controls the first voltage based on a voltage of the first feedback line and a voltage of the second feedback line.

Description

[0001] [Related Applications]

[0002] This application claims priority to Japanese Patent Application No. 2022-013273 (filed on January 31, 2022). This application incorporates the entire contents of that basic application by reference. Technical Field

[0003] Embodiments of the present invention relate to an information processing apparatus that supplies multiple power sources to a removable storage device. Background Technology

[0004] In recent years, small, high-speed, and high-capacity removable storage devices have been under development.

[0005] For example, as a removable storage device, there are known removable storage devices that operate using multiple power supplies with different voltages.

[0006] These removable storage devices are connected to the host via slots, making them more susceptible to voltage drops compared to ball grid array (BGA) type storage devices. Therefore, there is a growing demand for new technologies that can reliably supply voltage to removable storage devices. Summary of the Invention

[0007] One embodiment of the present invention provides an information processing apparatus capable of stably supplying voltage to a removable storage device.

[0008] According to an embodiment, the information processing apparatus includes: a holding unit capable of holding a removable storage device; and a power supply circuit for supplying a first voltage and a second voltage different from the first voltage to the removable storage device. The removable storage device includes: a plurality of first power terminals, each capable of being supplied with the first voltage; a plurality of second power terminals, each capable of being supplied with the second voltage; and a plurality of power ground terminals, each capable of being connected to a ground voltage. The plurality of first power terminals are electrically connected to each other. The plurality of second power terminals are electrically connected to each other. The plurality of power ground terminals are electrically connected to each other. The power supply circuit includes: a first wiring connected to a node capable of outputting the first voltage; a second wiring connected to a node capable of outputting the second voltage; a ground wiring connected to a node capable of outputting a ground voltage; and a plurality of feedback lines. When the removable storage device is held in the holding unit, a first feedback line of the plurality of feedback lines is electrically connected via the holding unit to one of the plurality of first power terminals, and the first wiring is electrically connected via the holding unit to the other terminals of the plurality of first power terminals. When the removable storage device is held in the holding part, the second feedback line of the plurality of feedback lines is electrically connected to one of the plurality of power ground terminals via the holding part, and the ground wiring is electrically connected to the other terminals of the plurality of power ground terminals via the holding part. When the removable storage device is held in the holding part, the second wiring is electrically connected to at least one of the plurality of second power terminals via the holding part. When the removable storage device is held in the holding part, the power circuit controls the first voltage based on the voltage of the first feedback line and the voltage of the second feedback line. Attached Figure Description

[0009] Figure 1 This is a diagram illustrating an example of the configuration of an information processing system implemented in this way.

[0010] Figure 2A This is a top view of the first side of the removable storage device according to the embodiment.

[0011] Figure 2B This is a side view of the removable storage device according to the implementation method.

[0012] Figure 2C This is a top view of the second side of the removable storage device according to the embodiment.

[0013] Figure 3 This is a diagram illustrating an example configuration of a removable storage device in an implementation method.

[0014] Figure 4 This is a top view showing the external shape of the removable storage device according to the embodiment, and an example of the configuration of multiple terminals.

[0015] Figure 5 This is a top view showing the external shape of the slot for the removable storage device in the embodiment and an example of the configuration of multiple lead terminals.

[0016] Figure 6 This is a side view showing the removable storage device in the slot in an embodiment.

[0017] Figure 7 This is a diagram illustrating an example of the configuration of multiple power terminals and a power ground terminal of a removable storage device that operates using dual power supplies.

[0018] Figure 8 This is a diagram showing the power voltage specifications of a removable storage device that operates using dual power supplies.

[0019] Figure 9 This is a block diagram illustrating an example of the power supply configuration of a removable storage device that operates using dual power supplies.

[0020] Figure 10 This is a diagram illustrating an example of the configuration of a step-down switching regulator.

[0021] Figure 11 It means Figure 10 The waveform diagram shows the relationship between the opening / closing of the first and second switches, the output voltage, and the feedback voltage.

[0022] Figure 12 This is a diagram illustrating a comparative example of the configuration of a host power supply that provides dual power to a removable storage device.

[0023] Figure 13 This is a diagram illustrating an example of the configuration of a host power supply in an implementation that supplies dual power to a removable storage device.

[0024] Figure 14 This is a diagram illustrating another configuration example of a host power supply for an implementation that supplies dual power to a removable storage device.

[0025] Figure 15 This is a diagram illustrating another configuration example of a host power supply that provides dual power to a removable storage device. Detailed Implementation

[0026] The embodiments will now be described with reference to the accompanying drawings.

[0027] Figure 1 This is a diagram illustrating an example configuration of the information processing system 1 in an implementation scheme. For example... Figure 1As shown, the information processing system 1 includes a host 5 (host device) and a removable storage device 10. The removable storage device 10 can be connected to various information processing devices such as personal computers and mobile devices that function as the host 5. The removable storage device 10 is provided with a plurality of terminals P, which are electrically connected to the printed circuit board substrate inside the host 5 via slots inside the host 5.

[0028] Next, refer to Figure 2A , Figure 2B and Figure 2C The external shape of the removable storage device 10 according to the embodiment will be described. Figure 2A This is a top view showing one surface of the removable storage device 10. Figure 2B This is a side view showing the side of the removable storage device 10. Figure 2C This is a top view showing another surface of the removable storage device 10.

[0029] In this specification, the X-axis, Y-axis, and Z-axis are defined. The X-axis, Y-axis, and Z-axis are orthogonal to each other. The X-axis is along the width of the removable storage device 10. The Y-axis is along the length (height) of the removable storage device 10. The Z-axis is along the thickness of the removable storage device 10.

[0030] The removable storage device 10 is a storage device that can be retained in a slot within the host 5 and removed from the slot within the host 5. The removable storage device 10 is held in place, for example, by being inserted into a slot within the host 5. The removable storage device 10 is configured to operate using multiple power supplies supplied from the host 5. These multiple power supplies have different voltages. The multiple power supplies supplied from the host 5 to the removable storage device 10, or the power wiring used to supply multiple power supplies from the host 5 to the removable storage device 10, are sometimes referred to as power rails.

[0031] For example, when the removable storage device 10 is implemented as a storage device having a power supply that operates using two power supplies supplied from the host 5, a first power supply with a first voltage is supplied to the removable storage device 10 via a first power rail from a first host power supply in the host 5, and a second power supply with a second voltage is supplied to the removable storage device 10 via a second power rail from a second host power supply in the host 5.

[0032] like Figure 2A As shown, the removable storage device 10 includes a thin plate-shaped package (body) 11. The body 11 of the removable storage device 10 is formed, for example, as a generally rectangular plate extending along the Y-axis direction. The Y-axis direction is the direction of the long side of the body 11 of the removable storage device 10.

[0033] The main body 11 is plate-shaped and has a first surface 21, a second surface 22, and a side surface 23. The first surface 21 and the second surface 22 are formed into a generally quadrilateral (rectangular) shape extending along the Y-axis direction. That is, the Y-axis direction is also the direction of the long side of the first surface 21 and the second surface 22.

[0034] Surface 1 21 is a generally flat surface facing the positive direction of the Z-axis. Surface 22 is located on the opposite side of surface 1 21 and is a generally flat surface facing the negative direction of the Z-axis.

[0035] Side 23 is disposed between the first surface 21 and the second surface 22, and has a first edge 31, a second edge 32, a third edge 33, a fourth edge 34, a first corner 35, a second corner 36, a third corner 37 and a fourth corner 38.

[0036] The first edge 31 extends along the X-axis direction and faces the positive Y-axis direction. The X-axis direction is the direction of the short sides of the body 11, the first surface 21, and the second surface 22, and includes the positive and negative X-axis directions.

[0037] The second edge 32 extends along the Y-axis and towards the negative X-axis. The third edge 33 is located on the opposite side of the second edge 32, extending along the Y-axis and towards the positive X-axis. The fourth edge 34 is located on the opposite side of the first edge 31, extending along the X-axis and towards the negative Y-axis.

[0038] The lengths of the second edge 32 and the third edge 33 are greater than the lengths of the first edge 31 and the fourth edge 34. The first edge 31 and the fourth edge 34 form the short side of the generally rectangular storage device 10, and the second edge 32 and the third edge 33 form the long side (side) of the generally rectangular removable storage device 10.

[0039] The first corner 35 is the corner portion between the first edge 31 and the second edge 32, connecting the end of the first edge 31 in the negative direction of the X-axis to the end of the second edge 32 in the positive direction of the Y-axis.

[0040] The first corner portion 35 extends in a straight line between the end of the first edge 31 in the negative X-axis direction and the end of the second edge 32 in the positive Y-axis direction. The first corner portion 35 is provided by setting the angle between the first edge 31 and the second edge 32 as a chamfer called C1.1 (also known as a chamfered C-angle). In other words, the first corner portion 35 is a chamfered portion C formed between the first edge 31 and the second edge 32.

[0041] The second corner portion 36 is the corner portion between the first edge 31 and the third edge 33, connecting the end of the first edge 31 in the positive X-axis direction to the end of the third edge 33 in the positive Y-axis direction. The second corner portion 36 extends in an arc shape between the end of the first edge 31 in the positive X-axis direction and the end of the third edge 33 in the positive Y-axis direction. The second corner portion 36 is provided by setting the angle between the first edge 31 and the third edge 33 as a so-called R0.2 rounded corner (also called a chamfered R-angle). In this way, the shapes of the first corner portion 35 and the second corner portion 36 are different from each other.

[0042] The third corner portion 37 connects the end of the second edge 32 in the negative Y-axis direction to the end of the fourth edge 34 in the negative X-axis direction. The fourth corner portion 38 connects the end of the third edge 33 in the negative Y-axis direction to the end of the fourth edge 34 in the positive X-axis direction. Both the third corner portion 37 and the fourth corner portion 38 extend in an arc shape, similar to the second corner portion 36.

[0043] The lengths of the main body 11, the first surface 21, and the second surface 22 in the Y-axis direction are set to approximately 18 ± 0.10 mm, and the lengths in the X-axis direction are set to approximately 14 ± 0.10 mm. That is, the distance between the first edge 31 and the fourth edge 34 in the Y-axis direction is set to approximately 18 ± 0.1 mm, and the distance between the second edge 32 and the third edge 33 in the X-axis direction is set to approximately 14 ± 0.10 mm. Furthermore, the lengths of the main body 11, the first surface 21, and the second surface 22 in the X-axis and Y-axis directions are not limited to this example.

[0044] The thickness of the body 11 in the Z-axis direction is set to approximately 1.4 mm ± 0.10 mm. That is, the distance between the first surface 21 and the second surface 22 in the Z-axis direction is set to approximately 1.4 mm ± 0.10 mm.

[0045] like Figure 2B As shown, the body 11 also has an inclined portion 39. The inclined portion 39 is the corner portion between the first surface 21 and the first edge 31, and extends in a straight line between the end of the first surface 21 in the positive direction of the Y axis and the end of the first edge 31 in the positive direction of the Z axis.

[0046] like Figure 2A As shown, a plurality of terminals are provided on the first surface 21 of the removable storage device 10. These terminals are also referred to as external connection terminals. Figure 2A In the diagram, multiple terminals are represented by small rectangles. Although not shown, they could also be squares.

[0047] Multiple terminals are configured, for example, in three columns: R1 (column 1), R2 (column 2), and R3 (column 3). The terminal group configured in column R1 is referred to as the first column terminal group. The first column terminal group includes, for example, multiple signal terminals used to transmit and receive differential signals for two channels (lanes) as specified in the PCIExpress (registered trademark) (PCIe) standard. The signal terminals corresponding to one channel include two terminals assigned to receive differential signal pairs and two terminals assigned to transmit differential signal pairs. The two terminals assigned to receive differential signal pairs and the two terminals assigned to transmit differential signal pairs are adjacent to each other across a ground terminal, which is interposed between the two terminals assigned to receive differential signal pairs and the two terminals assigned to transmit differential signal pairs. That is, any two terminals assigned differential signal pairs are surrounded by two ground terminals located on either side of those two terminals.

[0048] The terminal group in column R2 is referred to as the second terminal group. The second terminal group includes, for example, a power ground terminal and several signal terminals for optional signals. In addition, the second terminal group may also include an additional power terminal to correspond to a three-power supply configuration.

[0049] The terminal group of column R3 is referred to as the third terminal group. The third terminal group includes several signal terminals assigned with sideband signals as specified in the PCIe standard (e.g., reset signal PERST#, clock request signal CLKREQ#, reference clock pair CLKREF), one or more first power supply terminals supplied with a first power supply having a first voltage, one or more second power supply terminals supplied with a second power supply having a second voltage different from the first voltage, one or more power ground terminals, and several signal ground terminals.

[0050] Figure 3 This represents a configuration example of the removable storage device 10.

[0051] like Figure 3 As shown, inside the body 11 of the removable storage device 10, there is a substrate 12, a NAND (Not AND) flash memory 13, and a controller 14 for controlling the NAND flash memory 13. The NAND flash memory 13 and the controller 14 are mounted on the front side of the substrate 12. The NAND flash memory 13 includes a plurality of NAND flash memory dies stacked on the front side of the substrate 12.

[0052] The back side of substrate 12, opposite to the front side, is exposed and functions as the first surface 21. A [missing information - likely a component or feature] is disposed on the back side of substrate 12. Figure 2A The multiple terminals described herein.

[0053] The NAND flash memory 13 and the controller 14 are covered and sealed by molding resin 40 formed in such a way as to form the main body (body 11) of the removable storage device 10.

[0054] Figure 4 This is a top view showing the external shape of the removable storage device 10 and an example of the configuration of multiple terminals.

[0055] like Figure 4 As shown, the removable storage device 10 has multiple terminals P. Terminals P are sometimes also referred to as solder pads. Figure 4 The example shown illustrates a removable storage device 10 with 32 terminals P, but the number of terminals P is merely an example and not limited to this one. That is, the number of terminals P can be less than 32 or more than 32. Multiple terminals P are disposed on the back side of the substrate 12, exposed on the first surface 21. No terminals P are provided on the second surface 22. The second surface 22 can, for example, be used as a marking area.

[0056] like Figure 4 As shown, the first column of terminals arranged in the first column R1 contains 13 terminals P101 to P113, which are spaced apart from each other and arranged along the X-axis in a position closer to the first edge 31 than the fourth edge 34. Terminals P101 to P113 are arranged along the first edge 31 in the X-axis direction near the first edge 31.

[0057] The second terminal group in column R2 comprises six terminals P114 to P119, which are spaced apart and arranged along the X-axis closer to the fourth edge 34 than the first edge 31. Terminals P114 to P116 are arranged along the fourth edge 34 in the X-axis closer to the second edge 32 than the third edge 33. Terminals P117 to P119 are arranged along the fourth edge 34 in the X-axis closer to the third edge 33 than the second edge 32. In other words, terminals P114 to P116 are positioned between the center line (represented by a single-point chain line) of the removable storage device 10 and its body 11 in the X-axis direction and the second edge 32, while terminals P117 to P119 are positioned between the center line of the removable storage device 10 and its body 11 in the X-axis direction and the third edge 33. The spacing between terminals P116 and P117, which belong to the second column of terminal groups, is wider than the spacing between other terminals that belong to the second column of terminal groups and are adjacent in the X-axis direction (specifically, the spacing between terminals P114 and P115, the spacing between terminals P115 and P116, the spacing between terminals P117 and P118, and the spacing between terminals P118 and P119).

[0058] The third terminal group in column R3 comprises 13 terminals P120 to P132, which are spaced apart and arranged along the X-axis closer to the fourth edge 34 than the first edge 31. Terminals P120 to P132 in column R3 are arranged closer to the fourth edge 34 than terminals P114 to P119 in column R2.

[0059] Figure 5 This is a top view showing the external shape of the slot 100 that holds the removable storage device 10 and an example of the configuration of multiple lead terminals.

[0060] In slot 100, a plurality of lead terminals 104 are configured in three columns r1, r2, and r3, corresponding to the first, second, and third column terminal groups of the removable storage device 10, respectively. The lead terminals are sometimes referred to as spring leads. The removable storage device 10 is configured with its first surface 21 facing the slot 100, and the plurality of lead terminals 104 are arranged in a position... Figure 5 On slot 100.

[0061] There are 13 lead terminals 104 in the first column r1. Similarly, there are 6 lead terminals 104 in the second column r2 and 13 lead terminals 104 in the third column r3.

[0062] Each lead terminal 104 has a contact portion 105 at one end that contacts a corresponding terminal of the removable storage device 10. For example, a contact portion 105 that contacts a first power terminal of the removable storage device 10 functions as a first power terminal on the slot 100 side. Additionally, a contact portion 105 that contacts a second power terminal of the removable storage device 10 functions as a second power terminal on the slot 100 side. Furthermore, a contact portion 105 that contacts a power ground terminal of the removable storage device 10 functions as a power ground terminal on the slot 100 side. The other end of each lead terminal 104 has a slot substrate connection portion 106 that is soldered to a footprint of the printed circuit board substrate. Each lead terminal 104 is bonded to the frame 107 of the slot 100.

[0063] The frame 107 of the slot 100 has a first edge 111, a second edge 112, a third edge 113, a fourth edge 114, and a connecting portion 115. The first edge 111, the second edge 112, the third edge 113, and the fourth edge 114 correspond to the top, bottom, left, and right sides of the rectangular frame 107. The connecting portion 115 connects the vicinity of the middle of the second edge 112 with the vicinity of the middle of the third edge 113 to reinforce the frame 107 of the slot 100.

[0064] The 13 lead terminals 104 of the first column r1 are bonded to the first edge 111 of the frame 107. The 6 lead terminals 104 of the second column r2 are bonded to the connecting part 115 of the frame 107. The position of the connecting part 115 is determined by the arrangement of the second column r2. The 13 lead terminals 104 of the third column r3 are bonded to the fourth edge 114 of the frame 107.

[0065] Figure 6 This is a side view showing the removable storage device 10 remaining in slot 100.

[0066] Slot 100 can hold removable storage device 10. As for the type of slot 100, various types such as push-push type, push-pull type, and hinge type can be used. Here, a hinge type slot 100 will be described as an example.

[0067] The cover 120 is rotatably mounted on the frame 107 with the shaft 121, which functions as a hinge, as the fulcrum. With the cover 120 in the open position, the removable storage device 10 is held in place by the cover 120. The removable storage device 10 is held in place by inserting it into the cover 120, for example, while the cover 120 is in the open position. Then, the cover 120 is closed, and so on. Figure 6 As shown, each terminal P disposed on the first surface 21 of the removable storage device 10 contacts the contact portion 105 of the corresponding lead terminal 104 in the slot 100. Thus, each terminal P disposed on the first surface 21 of the removable storage device 10 is electrically connected to the wiring of the printed circuit substrate disposed in the host 5 via the lead terminal 104.

[0068] Thus, the removable storage device 10 is electrically connected to the printed circuit board substrate within the host 5 via the lead terminals 104 of the slot 100. Therefore, compared to embedded storage devices like ball grid array (BGA) type storage devices where each terminal is directly soldered to the printed circuit board substrate within the host, the number of terminals that can be configured in the removable storage device 10 is reduced. Due to this limitation on the number of terminals, the number of power terminals for each power supply is also limited. Consequently, in the removable storage device 10, there is a tendency for the current flowing to a single power terminal to become relatively large. For example, in the removable storage device 10, the maximum current that can flow through a single power terminal is set to 1.2A. This value is determined with consideration of the installation of the slot 100, and therefore, factors such as contact spring pressure, material, and the shape of the contact surface become design elements. For example, the slot 100 is installed in such a way that the voltage drop between the contact portion 105 and the slot substrate connection portion 106 when the maximum current flows through the lead terminal 104 is kept below a specified voltage and is very small.

[0069] Furthermore, there is a contact resistance value between each terminal P of the removable storage device 10 and each contact portion 105 of the slot 100. Since the contact portion 105 is part of the lead terminal 104, more precisely, there is a contact resistance value between each terminal P of the removable storage device 10 and each lead terminal 104 of the slot 100. Because the terminal P and the lead terminal 104 are not bonded by soldering, the contact resistance value between the terminal P and the lead terminal 104 is relatively large. Furthermore, there are power wirings connected to the host power supply on the printed circuit board substrate within the host 5. The voltage value of the power supplied from the host 5 to each power terminal of the removable storage device 10 is reduced by the voltage drop caused by the contact resistance value and the wiring resistance value of the power wiring. The contact resistance value between the terminal P and the lead terminal 104 is also considered as the contact resistance value of the device slot. Strictly speaking, there is a resistive component regardless of the contact length of the slot 100. Here, it is included in the contact resistance for simplification.

[0070] As described above, the contact resistance value, wiring resistance value, and the current flowing therein can cause a voltage drop, which reduces the voltage supplied to each power terminal of the removable storage device 10. Therefore, there is a tendency for the tolerance between the voltage supplied to each power terminal and the lower limit voltage value of each power supply required for the operation of the removable storage device 10 to become relatively small.

[0071] Next, an example of the power supply configuration of the removable storage device 10 will be explained.

[0072] Here, we will describe the removable storage device 10 that is configured with dual power supplies, that is, the removable storage device 10 that operates using dual power supplies.

[0073] Figure 7 This diagram illustrates an example configuration of multiple power supply terminals and multiple power ground terminals of a removable storage device 10 that operates using dual power supplies. Figure 7The example illustrates a scenario where the number of power terminals supplied with the first power source is 3, the number of power terminals supplied with the second power source is 3, and the number of power ground terminals for current return is 5. The combined current supplied from the first power terminal and the power current supplied from the second power terminal returns to the first and second power supply circuits via the power ground terminals. The signal ground and the power ground have the same voltage level and are electrically connected, but are configured such that no power current flows to the signal ground terminal. The number of power terminals supplied with the first power source, the number of power terminals supplied with the second power source, and the number of power ground terminals for current return are not limited to this example; the number of power terminals supplied with the first power source, the number of power terminals supplied with the second power source, and the number of power ground terminals for current return are all acceptable.

[0074] The first power supply (PWR_1) supplies power to, for example, three terminals included in the third row of terminals, specifically terminals P130, P131, and P132. Terminals P130, P131, and P132 function as power terminals for the first power supply (PWR_1). Terminals P130, P131, and P132 are electrically connected to each other inside the removable storage device 10. As described above, the maximum current supplied to one power terminal is, for example, 1.2A, therefore a maximum current of up to 3.6A can be supplied to the three power terminals for the first power supply (PWR_1).

[0075] The second power supply (PWR_2) supplies power to, for example, three terminals included in the third row of terminals, specifically terminals P126, P127, and P128. Terminals P126, P127, and P128 function as power terminals for the second power supply (PWR_2). Terminals P126, P127, and P128 are electrically connected to each other inside the removable storage device 10. As described above, the maximum current supplied to one power terminal is, for example, 1.2A, therefore, a maximum current of up to 3.6A can be supplied to the three power terminals for the second power supply (PWR_2).

[0076] The four terminals in the second terminal group, specifically terminals P114, P115, P118, and P119, together with the one terminal P124 in the third terminal group, function as a power ground terminal for the common power ground (PGND) of the first power supply (PWR_1) and the second power supply (PWR_2). Terminals P114, P115, P118, P119, and P124 are electrically connected to each other inside the removable storage device 10. As described above, the maximum current supplied to one power terminal is, for example, 1.2A, thus allowing a maximum return current of up to 6.0A to flow to the five terminals that function as power ground terminals. Furthermore, the power ground terminals are provided separately from the signal ground terminals. This means that the combined current of the first power supply (PWR_1) and the second power supply (PWR_2) is a maximum of 6.0A.

[0077] Figure 8 This is a diagram showing the power supply voltage specifications of the removable storage device 10 that operates using dual power supplies.

[0078] The first power source (i.e., power rail PWR_1) has, for example, a voltage of 2.5V. 2.5V is the nominal value of the voltage of the first power source (PWR_1). In practice, the first power source (PWR_1) has a permissible voltage range corresponding to a certain power source variation rate. For example, the minimum voltage of the first power source (PWR_1) with a voltage of 2.5V is set to 2.4V, and the maximum voltage is set to 2.7V. In this case, the minimum and maximum values ​​are not symmetrical relative to the nominal values; the minimum has a tolerance of only 0.1V, while the maximum has a tolerance of 0.2V.

[0079] The second power supply (i.e., power rail PWR_2) has, for example, a voltage of 1.2V. 1.2V is a voltage widely used for power supplies in the interfaces of general storage devices. 1.2V is the nominal value of the second power supply (PWR_2); in reality, the second power supply (PWR_2) has a permissible voltage range corresponding to a certain power supply variability rate. For example, the minimum voltage of the second power supply (PWR_2) with a voltage of 1.2V is set to 1.14V, and the maximum voltage is set to 1.26V. In this case, the minimum and maximum values ​​are symmetrical with respect to the nominal value, with a tolerance of 0.06V on both the lower and upper limits. That is, a power supply with much smaller tolerances than the first power supply (PWR_1) is required, resulting in higher precision.

[0080] Figure 9 This is a block diagram illustrating an example of the power supply configuration of a removable storage device 10 that operates using dual power supplies.

[0081] The removable storage device 10 includes a NAND flash memory 13, which includes a NAND interface circuit 131 and a memory cell array 132, also known as a NAND cell array.

[0082] The NAND interface circuit 131 performs the following actions: receiving instruction sequences (read instruction sequences, write instruction sequences, erase instruction sequences, etc.) and data from the controller 14; writing data to the NAND cell array based on the received write instruction sequences; reading data from the NAND cell array based on the received read instruction sequences; erasing data in blocks based on the received erase instruction sequences; and sending the status and read data to the controller 14.

[0083] The storage cell array 132 contains multiple blocks. Each block contains multiple pages. Each block is a unit for data erase operations. Each page is a unit for data write operations and data read operations.

[0084] The first power supply (PWR_1) with a voltage of 2.5V is mainly used to power the memory cell array 132. The second power supply (PWR_2) with a voltage of 1.2V is mainly used to power the NAND interface circuit 131.

[0085] The controller 14 includes a physical layer (PHY-A) 141 containing analog circuitry, core logic 142, NAND interface circuitry 143, and an LDO (Low Drop Output) regulator 144.

[0086] The physical layer (PHY-A) 141 communicates with the host 5 via a PCIe serial bus. More specifically, the physical layer (PHY-A) 141 communicates with the host 5 using multiple channels (e.g., two channels) of PCIe signals (each channel has two pairs of differential signals) and transmits and receives several PCIe sideband signals with the host 5.

[0087] The core logic 142 contains various logics used to perform the internal actions of the controller 14. This core logic 142 includes, for example, processing the interpretation and execution of instructions from the host 5, and ECC (Error Correcting code) encoding / decoding.

[0088] NAND interface circuit 143 is an interface circuit that performs communication with NAND flash memory 13. NAND interface circuit 143 performs the actions of sending instruction sequences (read instruction sequences, write instruction sequences, erase instruction sequences, etc.) and data to NAND flash memory 13, and receiving status and reading data from NAND flash memory 13.

[0089] exist Figure 9 In the power supply configuration, the first power supply (PWR_1) with 2.5V is also used to generate the internal power supply that enables the physical layer (PHY-A) 141 to operate and the internal power supply that enables the core logic 142 to operate.

[0090] More specifically, a first power supply of 2.5V (PWR_1) is supplied to both the LDO regulator 144 and the DC (Direct Current) / DC converter 151. The LDO regulator 144 converts the first power supply of 2.5V (PWR_1) to a specified voltage (e.g., 1.8V) lower than 2.5V, and supplies this converted specified voltage to the physical layer (PHY-A) 141 as an internal power supply to enable the physical layer (PHY-A) 141. The physical layer (PHY-A) 141 requires a stabilized power supply voltage for analog circuitry, and is therefore supplied with voltage by the LDO regulator 144, which is suitable for voltage stabilization. Due to relatively low current consumption, power loss is low despite the use of the LDO 144. The DC / DC converter 151 converts the first power supply of 2.5V (PWR_1) to another specified voltage (e.g., 0.8V) lower than 2.5V, and supplies this converted specified voltage to the core logic 142 as an internal power supply to enable the core logic 142. The voltage of the core logic 142 is determined by the LSI (Large Scale Integration) technology used by the controller. Because a relatively large current is required when operating at high frequency, a high-efficiency DC / DC converter 151 is more suitable.

[0091] The current consumed by the first power supply (PWR_1) in the removable storage device 10 is the sum of the current consumed by the memory cell array 132, the core logic 142, and the physical layer (PHY-A) 141. Therefore, the current consumed by the first power supply (PWR_1) in the removable storage device 10 is related to the configuration of the memory cell array 132, the core logic 142, and the physical layer (PHY-A) 141, as well as the performance of the removable storage device 10.

[0092] The current consumed by the removable storage device 10 from the second power supply (PWR_2) is the sum of the current consumed by the NAND interface circuit 131 in the NAND flash memory 13 and the current consumed by the NAND interface circuit 143 in the controller 14. Therefore, the current consumed by the removable storage device 10 from the second power supply (PWR_2) is related to the configuration of the NAND interface circuits 131 and 143, and the performance of the removable storage device 10.

[0093] Next, the power supply configuration of host unit 5 will be explained. For example, a step-down switching regulator is used in the host power supply. Below, firstly, referring to... Figure 10 This section explains the step-down type switching regulator.

[0094] Figure 10 This is a diagram illustrating an example of the configuration of a step-down switching regulator.

[0095] A buck converter converts the input voltage Vi into an output voltage Vo that is lower than the input voltage Vi. In the buck converter, a feedback line Wf is drawn from the measurement point Pf on the output side, and a feedback line Wg is drawn from the measurement point Pg on the power supply ground side. The feedback lines Wf and Wg are connected to a voltage divider circuit VD. The voltage divider circuit VD includes a series circuit consisting of a first resistor Re1 and a second resistor Re2 connected in series. The voltage divider circuit VD reduces the output voltage Vo to the feedback voltage Vfb and then outputs it to the switch control circuit SC. The feedback voltage Vfb is determined by the output voltage Vo and the resistance ratio of the first resistor Re1 and the second resistor Re2. The switch control circuit SC compares the feedback voltage Vfb output from the voltage divider circuit VD with the reference voltage Vref output from the reference voltage generation circuit RG. Based on the comparison result, the first switch SW1 and the second switch SW2 are alternately turned on / off in a manner that keeps the average output voltage constant. The first switch SW1 is sometimes referred to as the high-side switch, and the second switch SW2 is sometimes referred to as the low-side switch.

[0096] With switch SW1 open and switch SW2 closed, as indicated by the arrow on the single-point link, current flows from the input side to the output side through switch SW1 and the output inductor Lo. At this time, energy corresponding to the current is stored in the output inductor Lo. Furthermore, with switch SW1 open and switch SW2 closed, as indicated by the arrow on the single-point link, a return current flows from the power supply ground side to the input side. The magnitude of the return current is the same as the current flowing from the input side to the output side. If switch SW1 is switched off and switch SW2 is switched on, as indicated by the dashed arrow, current flows from the power supply ground side to the output side through switch SW2 and the output inductor Lo. This current flows through the release of energy stored in the output inductor Lo and decreases over time. In a buck-type switching regulator, the storage of energy in the output inductor Lo and the release of energy from the output inductor Lo are alternately linked to the opening / closing of switch SW1 and switch SW2.

[0097] The output voltage Vo can be approximately determined by the ratio of the period during which the first switch SW1 is open to the period during which the second switch SW2 is open (in other words, the period during which the first switch SW1 is closed). More specifically, the output voltage Vo can be approximately determined based on equation (1). However, this equation is a simplified version with the voltages generated across switches SW1 and SW2 set to zero.

[0098]

[0099] The second term in equation (1) is called the duty cycle term. By controlling this duty cycle, the output voltage Vo is controlled to be fixed.

[0100] In a step-down switching regulator, to control the duty cycle, feedback lines Wf and Wg are drawn from the measurement point Pf and measurement point Pg respectively, monitoring the output voltage Vo. While feedback lines Wf and Wg contain wiring resistances, the voltage divider circuit VD at the connection point includes high-resistance resistors Re1 and Re2, so almost no current flows to the feedback lines Wf and Wg. That is, during feedback, the voltage drop caused by the wiring resistance Rf of feedback line Wf and the wiring resistance Rg of feedback line Wg is minimized to a negligible level. Therefore, the output voltage Vo can be fed back with good accuracy, thereby enabling proper control of the duty cycle. Furthermore, the statement that the voltage drop caused by the wiring resistance Rf of the feedback wiring Wf and the wiring resistance Rg of the feedback wiring Wg is negligible means that even if the measurement points Pf and Pg are configured far away from the switch control circuit SC, making the feedback wiring Wf and Wg longer, it will not affect the control of the duty cycle.

[0101] Figure 11 It means Figure 10 The diagram shows the waveforms relating the opening / closing of switch SW1 and switch SW2, the output voltage Vo, and the feedback voltage Vfb. When switch SW1 is open and switch SW2 is closed, the output voltage Vo increases. Therefore, the feedback voltage Vfb also increases in the same way as the output voltage Vo. Comparing the magnitudes of the feedback voltage Vfb and the reference voltage Vref reveals that: due to the hysteresis characteristic of the feedback voltage Vfb relative to the reference voltage Vref, when the feedback voltage Vfb increases to a certain extent, switch SW1 switches to closed and switch SW2 switches to open, causing the output voltage Vo to decrease. Similarly, due to the hysteresis characteristic of the feedback voltage Vfb relative to the reference voltage Vref, when the feedback voltage Vfb decreases to a certain extent, switch SW2 switches to closed and switch SW1 switches to open, causing the output voltage Vo to increase. The output voltage Vo is determined by... Figure 10 The output capacitor Co is smoothed out, thus exhibiting a ripple voltage waveform with slight voltage fluctuations. Therefore, the feedback voltage Vfb also exhibits a ripple voltage waveform similar to the output voltage Vo. To achieve stable operation of the on / off control, a certain degree of hysteresis is required, which generates ripple voltage. Therefore, the ripple voltage of the output voltage Vo should be compared, for example, with... Figure 8 The power supply circuit is designed in a way that minimizes the range of power supply voltage fluctuations.

[0102] Figure 12 This diagram illustrates the configuration of a host power supply PS-A in a comparative example that supplies dual power to the removable storage device 10. The host power supply PS-A is a power supply circuit comprising a first host power supply PS1-A (Power Supply - 2.5V) supplying a first power supply with a voltage of 2.5V and a second host power supply PS2-A (Power Supply - 1.2V) supplying a second power supply with a voltage of 1.2V. Both the first host power supply PS1-A and the second host power supply PS2-A use a buck-type switching regulator. The input voltage Vi1 of the first host power supply PS1-A is greater than 2.5V, and the input voltage Vi2 of the second host power supply PS2-A is greater than 1.2V. The input voltage Vi2 of the second host power supply PS2-A may also be the same as the input voltage Vi1 of the first host power supply PS1-A. Furthermore, the basic configuration and operating principle of the buck-type switching regulator have been described in reference [reference needed]. Figure 10 and Figure 11 As already explained, its detailed description is omitted here.

[0103] exist Figure 12In the configuration shown, the feedback loops of the step-down switching regulators in the first main power supply PS1-A and the second main power supply PS2-A are closed loops within each main power supply. Specifically, in the first main power supply PS1-A, the output-side feedback wiring Wf1 is drawn from the measurement point Pf1 within the first main power supply PS1-A, and the power supply ground-side feedback wiring Wg1 is drawn from the measurement point Pg1 within the first main power supply PS1-A. Similarly, in the second main power supply PS2-A, the output-side feedback wiring Wf2 is drawn from the measurement point Pf2 within the second main power supply PS2-A, and the power supply ground-side feedback wiring Wg2 is drawn from the measurement point Pg2 within the second main power supply PS2-A.

[0104] The first main power supply PS1-A monitors its output voltage Vo1 based on feedback from measurement point Pf1 on the output side and measurement point Pg1 on the power ground side. The voltage divider circuit VD1 within the first main power supply PS1-A reduces the output voltage Vo1 to the feedback voltage Vfb1 before outputting it to the switch control circuit SC1. The switch control circuit SC1 controls the opening / closing of the first switch SW1a and the second switch SW2a based on the feedback voltage Vfb1 and the reference voltage Vref1 output from the reference voltage generation circuit RG1. Accordingly, based on feedback from the measurement point Pf1 on the output side and the measurement point Pg1 on the power supply ground side, the output voltage Vo1 of the first host power supply PS1-A can be monitored. For example, when the feedback voltage Vfb1 generated based on the output voltage Vo1 of the first host power supply PS1-A is lower than the reference voltage Vref1, the period for opening the first switch SW1a is increased (in other words, the period for closing the second switch SW2a is increased), and when the feedback voltage Vfb1 is higher than the reference voltage Vref1, the period for closing the first switch SW1a is increased (in other words, the period for opening the second switch SW2a is increased), the opening / closing of the first switch SW1a and the second switch SW2a can be controlled in such a way that the duty cycle is close to that shown in equation (1).

[0105] Similarly, the second main power supply PS2-A monitors its output voltage Vo2 based on feedback from measurement point Pf2 on the output side and measurement point Pg2 on the power ground side. The voltage divider circuit VD2 within the second main power supply PS2-A reduces the output voltage Vo2 to the feedback voltage Vfb2 before outputting it to the switch control circuit SC2. The switch control circuit SC2 controls the opening / closing of the first switch SW1b and the second switch SW2b based on the feedback voltage Vfb2 and the reference voltage Vref2 output from the reference voltage generation circuit RG2. Accordingly, based on feedback from the measurement point Pf2 on the output side and the measurement point Pg2 on the power supply ground side, the output voltage Vo2 of the second host power supply PS2-A can be monitored. For example, the opening / closing of the first switch SW1b and the second switch SW2b can be controlled in such a way that when the feedback voltage Vfb2 generated based on the output voltage Vo2 of the second host power supply PS2-A is lower than the reference voltage Vref2, the period for opening the first switch SW1b is increased (in other words, the period for closing the second switch SW2b is increased), and when the feedback voltage Vfb2 is higher than the reference voltage Vref2, the period for closing the first switch SW1b is increased (in other words, the period for opening the second switch SW2b is increased).

[0106] However, to supply a voltage lower than the output voltage Vo1 to terminals P130, P131, and P132, which function as the first power supply terminals in the removable storage device 10, the amount of voltage drop is equal to the voltage drop caused by the wiring resistance Ra and Rb of the power cable connecting the first host power supply PS1-A to the slot 100, and the contact resistance Rs of the slot 100. Similarly, to supply a voltage lower than the output voltage Vo2 to terminals P126, P127, and P128, which function as the second power supply terminals in the removable storage device 10, the amount of voltage drop is equal to the voltage drop caused by the wiring resistance Rc and Rd of the power cable connecting the second host power supply PS2-A to the slot 100, and the contact resistance Rs of the slot 100. Here, as mentioned above, only the voltage drop caused by wiring resistance and contact resistance is mentioned; more precisely, a voltage drop also occurs due to the wiring inductance corresponding to the time-varying current flowing in the power cable.

[0107] That is, although the output voltage Vo1 of the first host power supply PS1-A has been adjusted based on feedback from measuring points Pf1 and Pg1 within the first host power supply PS1-A, because the voltage drop caused by the wiring resistors Ra and Rb and the contact resistance Rs is not taken into account, it is possible that the desired voltage (i.e., the voltage within the allowable voltage variation range) is not supplied to the power terminals of the first power supply of the removable storage device 10. Similarly, although the output voltage Vo2 of the second host power supply PS2-A has been adjusted based on feedback from measuring points Pf2 and Pg2 within the second host power supply PS2-A, because the voltage drop caused by the wiring resistors Rc and Rd and the contact resistance Rs is not taken into account, it is possible that the desired voltage (i.e., the voltage within the allowable voltage variation range) is not supplied to the power terminals of the second power supply of the removable storage device 10. In particular, the second power supply, because its voltage value is 1.2V and its allowable voltage variation range is as small as ±0.06V, therefore, Figure 12 In the configuration shown, there is a higher possibility that the desired voltage is not supplied to the power terminal for the second power supply of the removable storage device 10.

[0108] The following section explains the components that can solve this problem.

[0109] Figure 13 This is a diagram illustrating an example configuration of the host power supply PS-B in an embodiment that supplies dual power to the removable storage device 10. Figure 13 The configuration (Example-1) applies to cases where the current consumption of the first host power supply PS1-B (Power Supply - 2.5V) supplied with a first power supply of 2.5V and the current consumption of the second host power supply PS2-B (Power Supply - 1.2V) supplied with a second power supply of 1.2V are both 2.0A or less. The host power supply PS-B is also referred to as the power supply circuit. The first host power supply PS1-B is also referred to as the first host power supply circuit. The second host power supply PS2-B is also referred to as the second host power supply circuit. Furthermore, the standard maximum current supplied to one power terminal of the removable storage device 10 is 1.2A, but for ease of explanation, considering tolerances, the upper limit of the installed current supplied to one power terminal is set to 1.0A for explanation.

[0110] Since the current consumed by the first host power supply PS1-B is less than 2.0A, and the maximum current supplied to a single power terminal is 1.0A, two power terminals are sufficient for the first power supply. Therefore, in this configuration, one of the three terminals functioning as the power terminal for the first power supply functions as a feedback terminal for feeding back the voltage supplied to the other two terminals from the first host power supply PS1-B. That is, in this configuration, this feedback terminal functions as a measurement point on the output side of the first host power supply PS1-B. The remaining two terminals, which function as the power terminal for the first power supply, are connected via slot 100 to the power wiring for supplying the first power supply (connected to the wiring that can output 2.5V). Figure 13 The diagram illustrates the following: Terminals P130, P131, and P132 (which can be supplied with 2.5V) function as power terminals for the first power supply. Terminal P130 functions as a feedback terminal for the first power supply, while terminals P131 and P132 function as terminals connected to the power wiring used to supply the first power supply. Furthermore, terminals P131 and P132 can also replace terminal P130 as feedback terminals for the first power supply.

[0111] The lead terminal 104 of the slot 100, which contacts the feedback terminal (terminal P130) for the first power supply, is connected to the voltage divider circuit VD1 within the first main power supply PS1-B via feedback wiring Wf1a. Although feedback wiring Wf1a is more... Figure 12 The feedback wiring Wf1 shown is long, but because the voltage divider circuit VD1 contains a high-resistivity load, almost no current flows to the feedback wiring Wf1a. Therefore, the voltage drop caused by the contact resistance Rs of the lead terminal 104 (contact portion 105) of the slot 100 that contacts terminal P130 and the wiring resistance Rf1a of the feedback wiring Wf1a is negligible, thereby enabling accurate feedback of the voltage supplied from terminal P130 to the first host power supply PS1-B to terminals P131 and P132.

[0112] Similarly, since the current consumed by the second host power supply PS2-B is less than 2.0A, and the maximum current supplied to a single power terminal is 1.0A, two power terminals are sufficient for the second power supply. Therefore, in this configuration, one of the three terminals functioning as the power terminal for the second power supply functions as a feedback terminal for feeding back the voltage supplied to the other two terminals from the second host power supply PS2-B. That is, in this configuration, this feedback terminal functions as a measurement point on the output side of the second host power supply PS2-B. The remaining two terminals, which function as the power terminal for the second power supply, are connected via slot 100 to the power wiring for supplying the second power supply (connected to the wiring that can output 1.2V). Figure 13 The diagram illustrates the following: Terminals P126, P127, and P128 (which can be supplied with 1.2V) function as power terminals for a second power supply. Terminal P126 functions as a feedback terminal for the second power supply, while terminals P127 and P128 function as terminals connected to the power wiring used to supply the second power supply. Furthermore, terminals P127 and P128 can also replace terminal P126 as feedback terminals for the second power supply.

[0113] The lead terminal 104 of the slot 100, which contacts the feedback terminal (terminal P126) for the second power supply, is connected via feedback wiring Wf2a to the voltage divider circuit VD2 within the second main power supply PS2-B. Although feedback wiring Wf2a is more... Figure 12 The feedback wiring Wf2 shown is long, but because the voltage divider circuit VD2 contains a high-resistivity load, almost no current flows to the feedback wiring Wf2a. Therefore, the voltage drop caused by the contact resistance Rs of the lead terminal 104 (contact portion 105) of the slot 100 that contacts terminal P126 and the wiring resistance Rf2a of the feedback wiring Wf2a is negligible, thereby enabling accurate feedback of the voltage supplied from terminal P126 to the second host power supply PS2-B to terminals P127 and P128.

[0114] Furthermore, since the current consumption from the first host power supply PS1-B and the second host power supply PS2-B are both below 2.0A, it is sufficient to allow a return current of up to 4.0A to flow. Therefore, four power grounding terminals shared by the first host power supply PS1-B and the second host power supply PS2-B are enough. Thus, in this configuration, one of the five terminals functioning as a power grounding terminal functions as a feedback terminal for power grounding. That is, this feedback terminal functions as a measurement point on the power grounding side. The remaining four terminals functioning as power grounding terminals are connected via slot 100 to the power grounding wiring (the wiring connected to the node that can output ground voltage) used to flow the return current. Figure 13 The diagram illustrates the following: among terminals P114, P115, P118, P119, and P124 (which can be connected to terminals P114, P115, P118, P119, and P124 for grounding voltage), terminal P124 functions as a feedback terminal for power grounding. Terminals P114, P115, P118, and P119 function as terminals connected to the power grounding wiring used to carry return current. Furthermore, terminals P114, P115, P118, and P119 can also replace terminal P124 as feedback terminals for power grounding.

[0115] The lead terminal 104 of the slot 100, which contacts the feedback terminal P124 for power supply grounding, is connected via feedback wiring Wg to the voltage divider circuit VD1 in the first host power supply PS1-B and the voltage divider circuit VD2 in the second host power supply PS2-B. At node N1 near the slot 100, the feedback wiring Wg branches into feedback wiring Wg1a and feedback wiring Wg2a.

[0116] Feedback wiring Wg1a is connected to the voltage divider circuit VD1 within the first host power supply PS1-B. Although feedback wiring Wg1a is... Figure 12 The feedback wiring Wg1 shown is long, but because the voltage divider circuit VD1 contains a high-resistivity load, almost no current flows to the feedback wiring Wg1a. Therefore, the voltage drop caused by the contact resistance Rs of the lead terminal 104 (contact 105) of the slot 100 that contacts terminal P124 and the wiring resistance Rg1a of the feedback wiring Wg1a is negligible, thereby enabling accurate feedback of the voltage (ground voltage) from terminal P124 to the first host power supply PS1-B to terminals P114, P115, P118 and P119.

[0117] Feedback wiring Wg2a is connected to the voltage divider circuit VD2 within the second host power supply PS2-B. Although feedback wiring Wg2a is... Figure 12 The feedback wiring Wg2 shown is long, but because the voltage divider circuit VD2 contains a high-resistivity load, almost no current flows to this feedback wiring Wg2a. Therefore, the voltage drop caused by the contact resistance Rs of the lead terminal 104 (contact 105) of the slot 100 that contacts terminal P124 and the wiring resistance Rg2a of the feedback wiring Wg2a is negligible, thereby enabling accurate feedback of the voltage (ground voltage) from terminal P124 to the second host power supply PS2-B to terminals P114, P115, P118, and P119.

[0118] Furthermore, the feedback lines Wf1a and Wg1a of the voltage divider circuit VD1 connected in the first main power supply PS1-B are a pair of feedback lines, ideally led out parallel like a differential pair. This helps suppress in-phase noise. To avoid inductive coupling with the output coil Lo1, the wiring is either shielded by routing to other layers of the multilayer PCB (Printed Circuit Board) or routed at a distance. Similarly, the feedback lines Wf2a and Wg2a of the voltage divider circuit VD2 connected in the second main power supply PS2-B are a pair of feedback lines, ideally led out parallel like a differential pair. This helps suppress in-phase noise. To avoid inductive coupling with the output coil Lo2, the wiring is either shielded by routing to other layers of the multilayer PCB or routed at a distance.

[0119] The switch control circuit SC1 within the first main power supply PS1-B controls the opening / closing of the first switch SW1a and the second switch SW2a in a manner that fixes the voltage applied between terminal P130, which functions as a feedback terminal for the first power supply, and terminal P124, which functions as a feedback terminal for power grounding, thereby adjusting the output voltage Vo1. In other words, the switch control circuit SC1 within the first main power supply PS1-B controls the opening / closing of the first switch SW1a and the second switch SW2a in a manner that fixes the voltage applied between feedback wiring Wf1a and feedback wiring Wg1a, thereby adjusting the output voltage Vo1 and bringing the voltage applied between the power supply terminal for the first power supply of the removable storage device 10 and the power ground terminal within the allowable voltage variation range.

[0120] Similarly, the switch control circuit SC2 within the second main power supply PS2-B controls the opening / closing of the first switch SW1b and the second switch SW2b in a manner that fixes the voltage applied between terminal P126, which functions as a feedback terminal for the second power supply, and terminal P124, which functions as a feedback terminal for power grounding, thereby adjusting the output voltage Vo2. In other words, the switch control circuit SC2 within the second main power supply PS2-B controls the opening / closing of the first switch SW1b and the second switch SW2b in a manner that fixes the voltage applied between feedback wiring Wf2a and feedback wiring Wg2a, thereby adjusting the output voltage Vo2 and converging the voltage applied between the power supply terminal for the second power supply of the removable storage device 10 and the power ground terminal within the allowable voltage variation range.

[0121] As explained above Figure 13 In the configuration shown (Example-1), one of the power terminals for the first power supply of the removable storage device 10 functions as a feedback terminal for the first power supply, one of the power terminals for the second power supply of the removable storage device 10 functions as a feedback terminal for the second power supply, and one of the power ground terminals of the removable storage device 10 functions as a feedback terminal for power grounding. Using these, the first and second power supply voltages actually supplied to the removable storage device 10 can be fed back to the host power supply PS-B. That is, the voltage affected by the voltage drop caused by the wiring resistances Ra, Rb, Rc, Rd of the power wiring and the contact resistance Rs of the slot 100 can be fed back, so the output voltages Vo1 and Vo2 can be adjusted in a way that eliminates the voltage drop caused by the wiring resistances Ra, Rb, Rc, Rd of the power wiring and the contact resistance Rs of the slot 100. Thus, the desired voltage (i.e., the voltage within the allowable voltage variation range) can be stably supplied to the power terminals for the first and second power supplies of the removable storage device 10.

[0122] In addition, Figure 13 In the configuration shown (Example-1), feedback wiring Wf1a and feedback wiring Wg1a are paired feedback wirings related to the first host power supply PS1-B, and are therefore also referred to as the first feedback wiring pair. Additionally, feedback wiring Wf2a and feedback wiring Wg2a are paired feedback wirings related to the second host power supply PS2-B, and are therefore also referred to as the second feedback wiring pair. Figure 13 In the configuration shown (Example-1), feedback wiring Wf1a is also referred to as the power supply side of the first feedback pair. Feedback wiring Wg1a is also referred to as the grounding side of the first feedback pair. Feedback wiring Wf2a is also referred to as the power supply side of the second feedback pair. Feedback wiring Wg2a is also referred to as the grounding side of the second feedback pair. Additionally, in Figure 13In the configuration shown (Example-1), the first switch SW1a and the first switch SW1b are also referred to as the first switch circuit. The second switch SW2a and the second switch SW2b are also referred to as the second switch circuit.

[0123] Figure 14 This diagram illustrates an example configuration of a host power supply PS-C that supplies dual power to the removable storage device 10. Figure 14 The configuration (Example-2) applies to situations where the current consumption of the first host power supply PS1-C (Power Supply_2.5V) supplied with a first power supply of 2.5V exceeds 2.0A, the current consumption of the second host power supply PS2-C (Power Supply_1.2V) supplied with a second power supply of 1.2V is less than 2.0A, and the combined current consumption of the first host power supply PS1-C and the second host power supply PS2-C is less than 4.0A. The host power supply PS-C is also referred to as the power supply circuit. The first host power supply PS1-C is also referred to as the first host power supply circuit. The second host power supply PS2-C is also referred to as the second host power supply circuit. Similarly, for ease of explanation, the upper limit of the installed current supplied to a single power terminal is set to 1.0A for the explanation, considering tolerances.

[0124] Although the maximum current supplied to a single power terminal is 1.0A, the current consumption exceeds 2.0A; therefore, three power terminals are required for the first power supply. In other words, in this configuration, it is not possible to... Figure 13 As in Example-1, one of the three terminals that function as the power supply terminal for the first power supply functions as the feedback terminal for the first power supply. Therefore, in the first host power supply PS1-C, a measurement point Pf1 on the output side is provided near the lead terminals 104 of the slot 100 that are in contact with the power supply terminals P130, P131, and P132 that function as the power supply terminals for the first power supply on the power supply line, and a feedback line Wf1b is led out from the measurement point Pf1. The near the lead terminals 104 for which the measurement point Pf1 on the output side is provided refers to, for example, the vicinity of the solder pads connected to each lead terminal 104, including the slot substrate connection portion 106 of each lead terminal 104.

[0125] Feedback wiring Wf1b is connected to the voltage divider circuit VD1 within the first host power supply PS1-C. Although feedback wiring Wf1b is... Figure 12The feedback wiring Wf1 shown is long, but because the voltage divider circuit VD1 contains a high-resistivity load, almost no current flows to this feedback wiring Wf1b. Therefore, the voltage drop caused by the wiring resistance Rf1b of the feedback wiring Wf1b is negligible, thus enabling accurate feedback of the voltage at measurement point Pf1 to the first host power supply PS1-C.

[0126] Furthermore, regarding the point that one of the power supply terminals for the second power supply functions as a feedback terminal for the second power supply, and the point that one of the power ground terminals functions as a feedback terminal for power grounding, and... Figure 13 The structures shown are identical, so detailed descriptions are omitted here.

[0127] The switch control circuit SC1 within the first main power supply PS1-C controls the opening / closing of the first switch SW1a and the second switch SW2a in a manner that fixes the voltage applied between the measurement point Pf1 and the feedback terminal P124, which functions as a power ground terminal, thereby adjusting the output voltage Vo1. In other words, the switch control circuit SC1 within the first main power supply PS1-C controls the opening / closing of the first switch SW1a and the second switch SW2a in a manner that fixes the voltage applied between the feedback wiring Wf1b and the feedback wiring Wg1a, which are a pair of feedback lines, thereby adjusting the output voltage Vo1 and bringing the voltage applied between the power supply terminal for the first power supply of the removable storage device 10 and the power ground terminal within the allowable voltage variation range.

[0128] In addition, the switch control circuit SC2 in the second main power supply PS2-C controls the opening / closing of the first switch SW1b and the second switch SW2b in a way that the voltage applied between the terminal P126, which functions as a feedback terminal for the second power supply, and the terminal P124, which functions as a feedback terminal for power grounding, is fixed, thereby adjusting the output voltage Vo2.

[0129] As explained above Figure 14 In the configuration shown (Example-2), although it is impossible to feed back the voltage supplied to terminals P130, P131, and P132, which function as power terminals for the first power supply, a feedback wiring Wf1b is drawn from the measurement point Pf1 located near the lead terminals 104 of the slot 100 that are in contact with terminals P130, P131, and P132, and the voltage of the measurement point Pf1 is fed back to the first host power supply PS1-C.

[0130] Accordingly, the voltage affected by the voltage drop caused by the wiring resistance Ra of the power supply wiring used to supply the first power supply can be fed back, and the output voltage Vo1 can be adjusted in a way that eliminates the voltage drop caused by the wiring resistance Ra. In this case, as described above, the voltage supplied to terminals P130, P131, and P132, which function as power supply terminals for the first power supply, cannot be fed back, and therefore the output voltage Vo1 cannot be adjusted in a way that eliminates the voltage drop caused by the contact resistance Rs of the slot 100 that contacts terminals P130, P131, and P132. However, the contact resistance Rs of the slot 100 that contacts terminals P130, P131, and P132 are connected in parallel, and the voltage drop caused by these contact resistances Rs has a smaller impact than the voltage drop caused by the wiring resistance Ra of the power supply wiring. Therefore, as long as the voltage drop caused by the wiring resistance Ra can be eliminated, the desired voltage (i.e., the voltage within the allowable voltage variation range) can be supplied very stably. Furthermore, since it is sufficient to supply a voltage within the allowable voltage variation range to the power supply terminal for the first power supply, and the first power supply with a voltage of 2.5V has a larger allowable voltage variation range than the second power supply with a voltage of 1.2V, it is sufficient to eliminate the voltage drop caused by the wiring resistance Ra.

[0131] Furthermore, the output voltage Vo2 from the PS2-C power supply of the second host can be compared with... Figure 13 The configuration shown is similarly adjusted, so its detailed description is omitted here.

[0132] In addition, Figure 14 In the configuration shown (Example-2), feedback wiring Wf1b and feedback wiring Wg1a are paired feedback wirings related to the first host power supply PS1-C, and are therefore also referred to as the first feedback wiring pair. Additionally, feedback wiring Wf2a and feedback wiring Wg2a are paired feedback wirings related to the second host power supply PS2-C, and are therefore also referred to as the second feedback wiring pair. Figure 14 In the configuration shown (Example-2), feedback wiring Wf1b is also referred to as the power supply side of the first feedback pair. Feedback wiring Wg1a is also referred to as the grounding side of the first feedback pair. Feedback wiring Wf2a is also referred to as the power supply side of the second feedback pair. Feedback wiring Wg2a is also referred to as the grounding side of the second feedback pair. Additionally, in Figure 14 In the configuration shown (Example-2), the first switch SW1a and the first switch SW1b are also referred to as the first switch circuit. The second switch SW2a and the second switch SW2b are also referred to as the second switch circuit.

[0133] Figure 15 This diagram illustrates an example configuration of a host power supply PS-D that supplies dual power to the removable storage device 10. Figure 15 The configuration (Example-3) applies to situations where the current consumption of the first host power supply PS1-D (Power Supply_2.5V) supplied with a first power supply of 2.5V exceeds 2.0A, the current consumption of the second host power supply PS2-D (Power Supply_1.2V) supplied with a second power supply of 1.2V is less than 2.0A, and the combined current consumption of the first host power supply PS1-D and the second host power supply PS2-D exceeds 4.0A. The host power supply PS-D is also referred to as the power supply circuit. The first host power supply PS1-D is also referred to as the first host power supply circuit. The second host power supply PS2-D is also referred to as the second host power supply circuit. Similarly, for ease of explanation, the upper limit of the installed current supplied to a single power terminal is set to 1.0A for the explanation, taking into account tolerances.

[0134] Although the maximum current supplied to a single power terminal is 1.0A, the current consumption exceeds 2.0A; therefore, three power terminals are required for the first power supply. That is, in this configuration, [the power supply is connected to the first power terminal]. Figure 14 Similarly, in the configuration (Example-2), a measurement point Pf1 on the output side is provided near the lead terminal 104 of the slot 100 that is used to supply the first power supply and which contacts the power supply terminal P130, terminal P131 and terminal P132 used as the first power supply terminal, and a feedback wiring Wf1b is led out from the measurement point Pf1.

[0135] Feedback wiring Wf1b is connected to the voltage divider circuit VD1 within the first host power supply PS1-D. Although feedback wiring Wf1b is... Figure 12 The feedback wiring Wf1 shown is long, but because the voltage divider circuit VD1 contains a high-resistivity load, almost no current flows to this feedback wiring Wf1b. Therefore, the voltage drop caused by the wiring resistance Rf1b of the feedback wiring Wf1b is negligible, thus enabling accurate feedback of the voltage at measurement point Pf1 to the first host power supply PS1-D.

[0136] Furthermore, since the combined current consumed by the first host power supply PS1-D and the second host power supply PS2-D exceeds 4.0A, five power ground terminals are required. That is, in this configuration, it is not possible to... Figure 13 The composition (Example-1) and Figure 14As in Example-2, one of the five terminals that function as power ground terminals functions as a feedback terminal for power grounding. Therefore, a power grounding measurement point Pg1 is provided near each lead terminal 104 of the slot 100 that contacts the power ground terminals P114, P115, P118, P119, and P124. A power grounding-side feedback line Wg1b, connected to the first host power supply PS1-D, and a power grounding-side feedback line Wg2b, connected to the second host power supply PS2-D, are drawn from this measurement point Pg1. The nearness of each lead terminal 104 for which the power grounding-side measurement point Pg1 is provided refers to, for example, the vicinity of the solder pads connected to each lead terminal 104, including the slot substrate connection portion 106 of each lead terminal 104.

[0137] Feedback wiring Wg1b is connected to the voltage divider circuit VD1 within the first host power supply PS1-D. Although feedback wiring Wg1b is... Figure 12 The feedback wiring Wg shown is long, but because the voltage divider circuit VD1 contains a high-resistivity load, almost no current flows to this feedback wiring Wg1b. Therefore, the voltage drop caused by the wiring resistance Rg1b of the feedback wiring Wg1b is negligible, thus enabling accurate feedback of the voltage at measurement point Pg1 to the first host power supply PS1-D.

[0138] Additionally, feedback wiring Wg2b is connected to the voltage divider circuit VD2 within the second host power supply PS2-D. Although feedback wiring Wg2b is more... Figure 12 The feedback wiring Wg2b shown is long, but because the voltage divider circuit VD2 contains a high-resistivity load, almost no current flows to this feedback wiring Wg2b. Therefore, the voltage drop caused by the wiring resistance Rg2b of the feedback wiring Wg2b is negligible, thus enabling accurate feedback of the voltage at measurement point Pg1 to the second host power supply PS2-D.

[0139] Furthermore, regarding the point that one of the power terminals for the second power supply functions as a feedback terminal for the second power supply, and... Figure 13 and Figure 14 The structures shown are identical, so detailed descriptions are omitted here.

[0140] The switch control circuit SC1 within the first main power supply PS1-D controls the opening / closing of the first switch SW1a and the second switch SW2a in a manner that fixes the voltage applied between measurement point Pf1 and measurement point Pg1, thereby adjusting the output voltage Vo1. In other words, the switch control circuit SC1 within the first main power supply PS1-D controls the opening / closing of the first switch SW1a and the second switch SW2a in a manner that fixes the voltage applied between the feedback wiring Wf1b and the feedback wiring Wg1b, which are a pair of feedback lines, thereby adjusting the output voltage Vo1 and bringing the voltage applied between the power supply terminal and the power ground terminal of the removable storage device 10 within the allowable voltage variation range.

[0141] Furthermore, the switch control circuit SC2 within the second main power supply PS2-D controls the opening / closing of the first switch SW1b and the second switch SW2b in a manner that fixes the voltage applied between terminal P126, which functions as the feedback terminal for the second power supply, and the measurement point Pg1, thereby adjusting the output voltage Vo2. In other words, the switch control circuit SC2 within the second main power supply PS2-D controls the opening / closing of the first switch SW1b and the second switch SW2b in a manner that fixes the voltage applied between feedback wiring Wf2a and feedback wiring Wg2b, which are a pair of feedback lines, thereby adjusting the output voltage Vo2 and converging the voltage applied between the power supply terminal for the second power supply of the removable storage device 10 and the power ground terminal within the allowable voltage variation range.

[0142] As explained above Figure 15 In the configuration shown (Example-3), it is impossible to feed back the voltage supplied to terminals P130, P131 and P132, which function as power supply terminals for the first power source, and the voltage supplied to terminals P114, P115, P118, P119 and P124, which function as power ground terminals.

[0143] However, a feedback wiring Wf1b is drawn from the measurement point Pf1 located near the lead terminals 104 of the slot 100 that contact terminals P130, P131, and P132, and the voltage of the measurement point Pf1 is fed back to the first host power supply PS1-D. Additionally, feedback wiring Wg1b and Wg2b are drawn from the measurement point Pg1 located near the lead terminals 104 of the slot 100 that contact terminals P114, P115, P118, P119, and P124, and the voltage of the measurement point Pg1 is fed back to the first host power supply PS1-D and the second host power supply PS2-D.

[0144] Accordingly, in the first main power supply PS1-D, the output voltage Vo1 can be adjusted by eliminating the voltage drop caused by the wiring resistances Ra and Rb of the power supply wiring. In this case, the output voltage Vo1 cannot be adjusted by eliminating the voltage drop caused by the contact resistance Rs of the slot 100 that contacts the power terminals P130, P131, and P132 (which function as the first power supply terminals) and the voltage drop caused by the contact resistance Rs of the slot 100 that contacts the power terminals P114, P115, P118, P119, and P124 (which function as power ground terminals). However, the contact resistance Rs of the slot 100 that contacts the power terminal of the first power supply and the contact resistance Rs of the slot 100 that contacts the power ground terminal are connected in parallel. The voltage drop caused by this contact resistance Rs has a smaller impact than the voltage drop caused by the wiring resistances Ra and Rb of the power supply wiring. Therefore, as long as the voltage drop caused by the wiring resistances Ra and Rb can be eliminated, the desired voltage (i.e., the voltage within the allowable voltage variation range) can be supplied very stably. In addition, since it is only necessary to supply the power terminal of the first power supply with a voltage within the allowable voltage variation range, and the first power supply with a voltage of 2.5V has a larger allowable voltage variation range tolerance than the second power supply with a voltage of 1.2V, it is sufficient to eliminate the voltage drop caused by the wiring resistances Ra and Rb.

[0145] Furthermore, in the second host power supply PS2-D, the output voltage Vo2 can be adjusted by eliminating the voltage drop caused by the wiring resistances Rc and Rd of the power supply wiring, and the voltage drop caused by the contact resistance Rs of the slot 100 that contacts the power terminals P126, P127, and P128, which function as the second power supply terminals. In this case, the output voltage Vo2 cannot be adjusted by eliminating the voltage drop caused by the contact resistance Rs of the slot 100 that contacts the power ground terminals P114, P115, P118, P119, and P124. However, the contact resistance Rs of the slot 100 that contacts the power ground terminal is connected in parallel, and the voltage drop caused by this contact resistance Rs has a smaller impact than the voltage drop caused by the wiring resistances Rc and Rd of the power supply wiring. Therefore, as long as the voltage drop caused by the wiring resistances Rc and Rd can be eliminated, the desired voltage (i.e., the voltage within the allowable voltage variation range) can be supplied very stably.

[0146] In addition, Figure 15In the configuration shown (Example-3), feedback wiring Wf1b and feedback wiring Wg1b are paired feedback wirings related to the first main power supply PS1-D, and are therefore also referred to as the first feedback wiring pair. Additionally, feedback wiring Wf2a and feedback wiring Wg2b are paired feedback wirings related to the second main power supply PS2-D, and are therefore also referred to as the second feedback wiring pair. Figure 15 In the configuration shown (Example-3), feedback wiring Wf1b is also referred to as the power supply side of the first feedback pair. Feedback wiring Wg1b is also referred to as the grounding side of the first feedback pair. Feedback wiring Wf2a is also referred to as the power supply side of the second feedback pair. Feedback wiring Wg2b is also referred to as the grounding side of the second feedback pair. Additionally, in Figure 15 In the configuration shown (Example-3), the first switch SW1a and the first switch SW1b are also referred to as the first switch circuit. The second switch SW2a and the second switch SW2b are also referred to as the second switch circuit.

[0147] According to at least one embodiment described above, the host power supply PS-B, host power supply PS-C, and host power supply PS-D can receive feedback on the voltage actually supplied to the terminal via at least one of the plurality of terminals P disposed in the removable storage device 10, thereby adjusting the output voltage based on the feedback. Accordingly, compared with the host power supply PS-A of the comparative example, the desired voltage (voltage within the allowable voltage variation range) can be stably supplied to the removable storage device 10.

[0148] Several embodiments of the present invention have been described, but these embodiments are merely illustrative and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, and are included within the scope of the invention as described in the claims and its equivalents.

[0149] [Explanation of Symbols]

[0150] PS-B, PS-C, PS-D console power supplies

[0151] PS1-B, PS1-C, PS1-D - First console power supply

[0152] PS2-B, PS2-C, PS2-D Second Console Power Supply

[0153] 10 Removable storage devices

[0154] P terminal

[0155] 100 slots

[0156] 104 lead terminal

[0157] 105 Contact Department

[0158] 106 Slot Substrate Connection

[0159] Rs Contact Resistance

[0160] Feedback wiring for Wf1a, Wf2a, Wg1a, and Wg2a

[0161] Rf1a, Rf2a, Rg1a, Rg2a are wiring resistors.

Claims

1. An information processing apparatus, comprising: The retaining section is capable of holding the removable storage device; as well as A power supply circuit is used to supply a first voltage and a second voltage different from the first voltage to the removable storage device; The removable storage device includes: a plurality of first power terminals, each capable of being supplied with a first voltage; a plurality of second power terminals, each capable of being supplied with a second voltage; and a plurality of power ground terminals, each capable of being connected to a ground voltage; wherein the plurality of first power terminals are electrically connected to each other, the plurality of second power terminals are electrically connected to each other, and the plurality of power ground terminals are electrically connected to each other. The power supply circuit has the following features: The first wiring is connected to a node capable of outputting the first voltage; the second wiring is connected to a node capable of outputting the second voltage; the ground wiring is connected to a node capable of outputting a ground voltage; and multiple feedback lines; When the removable storage device is held in the holding part, the first feedback line of the plurality of feedback lines is electrically connected to one of the plurality of first power terminals via the holding part, and the first wiring is electrically connected to the other terminals of the plurality of first power terminals via the holding part; When the removable storage device is held in the holding part, the second feedback line of the plurality of feedback lines is electrically connected to one of the plurality of power ground terminals via the holding part, and the power ground wiring is electrically connected to the other terminals of the plurality of power ground terminals via the holding part; When the removable storage device is held in the holding part, the second wiring is electrically connected via the holding part to at least one of the plurality of second power terminals; The power supply circuit controls the first voltage based on the voltage of the first feedback line and the voltage of the second feedback line when the removable storage device is held in the holding part.

2. The information processing apparatus according to claim 1, wherein... When the removable storage device is held in the holding part, the third feedback line of the plurality of feedback lines is electrically connected to one of the plurality of second power terminals via the holding part, and the second wiring is electrically connected to the other terminals of the plurality of second power terminals via the holding part; The second feedback line is electrically connected to one of the plurality of power grounding terminals via the holding part; When the removable storage device is held in the holding part, the power supply circuit controls the second voltage based on the voltage of the third feedback line and the voltage of the second feedback line.

3. The information processing apparatus according to claim 1, wherein... When the removable storage device is held in the holding part, the second wiring is electrically connected to all of the plurality of second power terminals via the holding part, and the third feedback line of the plurality of feedback lines is electrically connected to all of the plurality of second power terminals via the holding part; The second feedback line is electrically connected to one of the plurality of power grounding terminals via the holding part; When the removable storage device is held in the holding part, the power supply circuit controls the second voltage based on the voltage of the third feedback line and the voltage of the second feedback line.

4. The information processing apparatus according to claim 2 or 3, wherein The power supply circuit includes: The first portion of the first feedback line and the second feedback line extend parallel to each other; And a second portion that extends parallel to the third feedback line and the second feedback line.

5. The information processing apparatus according to claim 1, wherein... The number of the first power supply terminals is 3, the number of the second power supply terminals is 3, and the number of the power grounding terminals is 5.

6. The information processing apparatus according to claim 1, wherein The second voltage is higher than the first voltage.

7. The information processing apparatus according to claim 6, wherein The first voltage is 1.2V, and the second voltage is 2.5V.

8. The information processing apparatus according to claim 1, wherein The power supply circuit includes a step-down switching regulator; The switching regulator includes: the plurality of feedback lines; and a voltage divider circuit connected to the plurality of feedback lines. A reference voltage generation circuit generates a reference voltage. A switch control circuit is connected to the voltage divider circuit and the reference voltage generating circuit; The first and second switching circuits are controlled by the switch control circuit; and The voltage divider circuit generates a feedback voltage based on the voltage applied between the first feedback line and the second feedback line. The switch control circuit is configured to control the first voltage using the first switch circuit and the second switch circuit, based on the feedback voltage and the reference voltage.

9. An information processing apparatus, comprising: Multiple first power terminals; Multiple second power terminals; Multiple first power supply grounding terminals; as well as The power supply circuit has a first node capable of outputting a first voltage and a second node capable of outputting a second voltage different from the first voltage; and The power supply circuit includes: a first wiring connection to the first node; a second wiring connection to the second node; and a grounding wiring connection to a node capable of outputting a grounding voltage. And multiple feedback lines; The first feedback line of the plurality of feedback lines is connected to one of the plurality of first power terminals, and the first wiring is connected to the other terminals of the plurality of first power terminals; The second feedback line of the plurality of feedback lines is connected to one of the plurality of first power grounding terminals, and the grounding wiring is connected to the other terminals of the plurality of first power grounding terminals; The power supply circuit controls the first voltage based on the voltage of the first feedback line and the voltage of the second feedback line. The voltage of the first feedback line is based on the voltage of the other terminals among the plurality of first power supply terminals, and the voltage of the second feedback line is based on the voltage of the other terminals among the plurality of first power supply ground terminals.

10. The information processing apparatus according to claim 9, wherein When the information processing device is connected to the removable storage device, each of the plurality of first power terminals is connected to a plurality of third power terminals of the removable storage device, each of the plurality of second power terminals is connected to a plurality of fourth power terminals of the removable storage device, and each of the plurality of first power ground terminals is connected to a plurality of second power ground terminals of the removable storage device. The plurality of third power terminals are electrically connected to each other inside the removable storage device, the plurality of fourth power terminals are electrically connected to each other inside the removable storage device, and the plurality of second power ground terminals are electrically connected to each other inside the removable storage device.

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