(51) Int Cl.: G11C 5/14 ( ) G11C 7/10 ( )

Transcription

1 (19) TEPZZ _ 49B_T (11) EP B1 (12) EUROPEAN PATENT SPECIFICATION (4) Date of publication and mention of the grant of the patent: Bulletin 14/48 (21) Application number: (22) Date of filing: (1) Int Cl.: G11C /14 (06.01) G11C 7/ (06.01) (86) International application number: PCT/US08/079 (87) International publication number: WO 08/ ( Gazette 08/) (4) PROGRESSIVE POWER CONTROL OF A MULTI-PORT MEMORY DEVICE PROGRESSIVE LEISTUNGSSTEUERUNG EINER SPEICHERVORRICHTUNG MIT MEHREREN ANSCHLÜSSEN CONTRÔLE D ÉNERGIE PROGRESSIF D UN DISPOSITIF DE MÉMOIRE À PORTS MULTIPLES (84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR () Priority: US (43) Date of publication of application: Bulletin 09/2 (73) Proprietor: Silicon Image, Inc. Sunnyvale, CA 98 (US) (72) Inventors: KIM, Sungjoon Cupertino, CA 9014 (US) LEE, Dongyun San Jose, CA 9129 (US) KIM, Edward Palo Alto, CA (US) (74) Representative: Viering, Jentschura & Partner Patent- und Rechtsanwälte Am Brauhaus Dresden (DE) (6) References cited: EP-A EP-A US-A US-A US-A US-A US-A US-B EP B1 Note: Within nine months of the publication of the mention of the grant of the European patent in the European Patent Bulletin, any person may give notice to the European Patent Office of opposition to that patent, in accordance with the Implementing Regulations. Notice of opposition shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). Printed by Jouve, 7001 PARIS (FR)

2 1 EP B1 2 Description BACKGROUND [0001] The communications links across which computers-or parts of computers-talk to one another may be either serial or parallel. A parallel link transmits several streams of data (perhaps representing particular bits of a stream of bytes) along multiple channels (wires, printed circuit tracks, optical fibers, etc.), while a serial link transmits a single stream of data over only two wires (a positive and complementary signal). At first sight it would seem that a serial link must be inferior to a parallel one, because it can transmit less data on each clock tick. However, it is often the case that serial links can be clocked considerably faster than parallel links and can achieve a higher data rate. A number of factors allow serial links to be clocked at a greater rate. First, clock skew between different channels is not an issue (for un-clocked serial links). Second, a serial connection requires fewer interconnecting cables (e.g. wires/fibers) and hence occupies less space hallowing for better isolation of the channel from its surroundings. Finally, crosstalk is less of an issue because there are fewer conductors in proximity. In many cases, serial links are a better option because they are less expensive to implement. Many integrated circuits (ICs) have serial interfaces, as opposed to parallel ones, so that they have fewer pins and are therefore more economical. [0002] Despite their advantages, serial links tend to use more power than parallel links. In particular, when transmitting or receiving data, a serial link changes states very rapidly (called toggling). A small amount of power is consumed by each state change, thereby adding up to large power consumption over time. Serial links are also typically terminated on each end by a termination resistor and bias resistors. Without termination resistors, reflections of fast driver edges can cause multiple data edges that can cause data corruption. Termination resistors also reduce electrical noise sensitivity due to the lower impedance. The bias resistors bias the lines apart when the lines are not being driven. Without biasing resistors, the signal falls to zero (where electrical noise sensitivity is greatest) when no data is being transmitted. Both termination and bias resistors are therefore necessary; however, the additional resistance causes the link to consume a constant amount of power to keep the link alive. [0003] Consumers demand higher and higher speeds from electronic devices, but the higher the speed of the device the more power the device consumes. This is particularly a problem for mobile devices that have limited power available through on-board batteries. To provide the most benefit, these devices must have a long battery life while still providing consumers with a high degree of functionality. Previous attempts at power reduction have attempted to power down the device or place it into a lower power state when it is not in use, and then rapidly return it to full power when the user of the device wants to perform a function. However, this technique is not effective when a device is frequently in use and can still result in significant power being consumed. [0004] European Patent Application Publication No. EP12226 A2 of Fujitsu Limited, entitled "Multi-Port Memory Based on DRAM Core", regards a semiconductor memory device including a plurality of external ports receiving commands, including a cell array comprised of dynamic-type memory cells, where a refresh command may be internally generated when a port is deactivated. [000] European Patent Application Publication No. EP A2 of SGS-Thomson Microelectronics, Inc, entitled "A Semiconductor Memory With Separate Timeout Control for Read and Write Operations", regards semiconductor memory circuits having time-out control for certain circuitry, the control circuit including delay stages of different lengths, a shorter delay stage to define the time-out for a read operation and a longer delay stage to define the time-out for a write operation. [0006] According to the present invention, there is provided a method of progressively reducing power consumption according to claim 1 and a power control system according to claim 9. BRIEF DESCRIPTION OF THE DRAWINGS [0007] Figure 1 is a circuit diagram illustrating the components of a power control system in a serial port memory device. Figure 2 is a state machine that illustrates the states of a single port of the serial port memory device. Figure 3 is a state machine that illustrates the states of a host attached to a single port of the serial port memory device. Figure 4 is a state diagram illustrating the powerdown modes available to each bank of the serial port memory device. Figure is a circuit diagram that illustrates the termination of a serial link attached to a port. DETAILED DESCRIPTION [0008] A method and system for progressively reducing the power consumption of a serial memory device is provided (the "power control system"). A multi-port serial memory device is described in U.S. Patent Application No. /04,297, entitled "COMMUNICATlONS ARCHI- TECTURE FOR MEMORY-BASED DEVICES," (Attorney Docket No US00). The power control system configures the ports of a multi-port serial memory so that they can be enabled or disabled on a per-port 2

3 3 EP B1 4 basis. When data is not being transmitted or received on a port, a series of steps are taken to progressively depower portions of the port and cause the port to enter into a low-power state. By disabling certain ports and placing ports in a low-power state, the power consumption of the overall serial port memory is significantly reduced. Each port may be connected to a different host that accesses the device. Because ports can be shut down individually, hosts may still access the serial memory to perform certain functions using some ports while other ports are in a low-power state. In this way, the power control system reduces the power consumption of a device progressively, while still making the functionality of the device available for certain accessing hosts. [0009] In some embodiments, the power control system detects that a port is not in use based on a shut-off criteria (e.g., the activity of the port). For example, if the port is not transmitting or receiving, then the power control system will shut the port down. The power control system may wait for the expiration of a timeout based on the last time that data was received by the port to determine that the port is not active. The power control system may also receive a command from the host that indicates that no new data will be transmitted for a period, and the power control system may shut down the port in response to the command. [00] In some embodiments, the power control system removes the port clock signal and power for a shut down port. The port clock switches rapidly and consumes power that is not needed when the port is not in use. By removing the port clock and power to a port, the power control system further reduces power consumption. When the port is needed again, the power and the clock signal can be reapplied and the port returned to an operational state. For example, when powered down the power control system may detect a change in the signal state on the line that indicates that the port is needed again by a host. Upon detecting the change in signal state, the power control system powers the port back up by reversing the steps taken to power the port down. [0011] In some embodiments, if all ports are shut down, then the power control system lowers the core power including the clock generator and PLL to further reduce power consumption. The core power supplies each of the ports as well as common support circuitry. By removing the core power, the power control system achieves additional power savings. Since the clock generator and PLL can often consume a significant amount of power required by a circuit, shutting down the clock generator and PLL can result in significant power savings. [0012] In some embodiments, the power control system shuts down ports by removing termination at the port. The port is placed into common mode so that the voltage of the positive and complementary signals is the same. Removing the termination reduces power consumed. Moreover, neither the host nor the memory device is transmitting when a port is shut down, so both the host and memory device save power [0013] Figure 1 is a circuit diagram illustrating the components of the power control system and the serial memory device in one embodiment. The serial memory device contains a phase-locked loop (PLL), multiple banks of memory 1 and 11, four ports 1, 12, 1, and 13, a clock line 1 for each port, and a power line 1 for each port. The multiple banks of memory 1 and 11 are coupled to the four serial ports 1, 12, 1, and 13, thereby making the banks of memory accessible by one or more host devices that are connected to the ports. While the memory device is depicted as having only eight banks in two groups of four and four ports in Figure 1, the memory device may have any number of banks and ports. The number of banks and ports are typically determined by the number of accessing hosts and the particular application for which the memory device is being used. The power control system comprises an activity detection line 14, a clock switch 170, and a power switch 17 for each port, as well as power control logic 160, and a core power control module 16. The activity detection line 14 for each port is coupled to the clock switch 170, the power switch 17, and the power control logic 160. In some embodiments, the power control logic performs a logical AND operation on the activity detection line from each of the ports. The output from the power control logic 160 is coupled to the power control module 16. While Figure 1 depicts a certain switch configuration and power control logic, it will be appreciated that other configurations and constructions may perform similar functions to achieve the same result. For example, the power control logic may be implemented in software rather than in hardware, and the control signals used to trigger the power switch and the clock switch may be received from a central controller. As another example, the power control logic may be more complex depending on the number of ports that are contained in the memory device. [0014] A variety of power-saving techniques are implemented by the power control system in order to minimize the power consumption of the serial memory device. An activity detection line 14 is coupled to each port of the memory device, and carries a signal indicating when the port is active and when the port is inactive. The signal on the activity detection line is used to trigger various powersaving modes. For example, when the signal on the activity detection line indicates that a port is inactive, the power on power line 1 is disconnected from the port by switching off the power switch 17. Removing power from the port reduces the power consumption of the memory device. As another example, when a port is inactive the clock signal on clock line 1 is disabled for the port by switching off the clock switch 170. Shutting down the clock for the port reduces toggling and associated power consumption. As still another example, if power control logic 160 detects from the signal on the activity detection lines that all of the device ports are inactive, the power control logic signals the core power control module 16. Upon receiving the signal that all ports are inactive, the core power control module may 3

4 EP B1 6 further reduce power consumption by shutting down the core clock (not shown) and power to the PLL. Removing the clock signal and power to each port, or shutting down the core clock and power to the PLL, may be done immediately after a port is detected to be inactive, or after the expiration of a timeout period. The timeout period may vary in length for each port, for all ports, based on the application in which the memory device is being used, etc. [001] Figure 2 is a state machine that illustrates the states of a single port of a serial port memory device. When the port is first activated, the port is in a system reset state. The port then moves to a link reset state 2. As long as no data signal is being received on the port, the port remains in this state. In the link reset state 2, the port is not driven, and the voltage of the positive and complementary lines is the same due to termination. In order to minimize power, the clock and power to the port may also be removed as described above. When a signal is received on the port, the port moves to a frame search state 21. If the power and/or clock to the port are off when a signal is received, then the power and/or clock are turned back on. In the frame search state 21, the port is driven and the positive and complementary lines carry complementary signals. The port waits for a SYNC message from the host and transmits a SYNC2 message to the host. If the port stops receiving a signal, the port returns to the link reset state 2. If a SYNC message is detected from the host, then the port moves to an operational mode state 2. In the operational mode state 2, data is sent and received from the host. If the port stops receiving data, then the port can be powered down and returns to the link reset state 2. If any errors are detected during transmission, the port returns to the frame search state 21 to resynchronize with the host. [0016] Figure 3 is a state machine that illustrates the states of a host attached to a single port of a serial port memory device. When the host is first activated, the host is in a system reset state. The host then moves to a link reset state 3. As long as nothing is being sent, the host remains in this state. In the link reset state 3, the link is not terminated, and the voltage of the positive and complementary lines is the same (i.e., the lines are in squelch mode). When the host wants to send additional data, the host moves to a frame search state 31. In the frame search state 31, the link is terminated and the positive and complementary lines carry complementary signals. The host waits for a SYNC2 message from the port and transmits a SYNC message to the port. If the host decides to disable the link (e.g., by a timeout expiring or error parity), then the host returns to the link reset state 3. If a SYNC message is detected from the port, then the host moves to an operational mode state 3, else if a SYNC2 message is received, then the host waits for a SYNC message from the port. In the operational mode state 3, data is sent and received to the port. If at any point the host detects that the port is disabled, then the link can be powered down and the host returns to the link reset state 3. If any errors are detected during transmission, the host also returns to the link reset state 3 to resynchronize with the port. [0017] In some embodiments, the serial port memory may implement additional power saving modes at the bank level. For example, it is not necessary to refresh banks with no data in them. Refreshing banks consumes power, so avoiding a refresh of a bank saves power. In some embodiments, the serial port memory has four power-down modes, described as follows. Self-refresh - To enter the self-refresh mode, all ports are set by the power control system to idle state with no banks active. The PLL is stopped, and the external : reference clock (not shown) may be stopped. All other clocks are gated off to save power. All peripheral circuitry is disabled to save power as well. All banks are precharged before entering this mode. The core provides its own refresh timing, so this mode can be sustained indefinitely. The reference clock should be stable before exiting this mode. Links are retrained after exiting this mode. Precharge Power Down - To enter the precharge power down mode, all ports are set by the power control system to idle state with no banks active. The PLL is stopped, and the reference clock (not shown) may be stopped. All other clocks are gated off to save power. All peripheral circuitry is disabled to save power as well. All banks are precharged before entering this mode. No other operations are performed, so this mode should be exited before the next refresh cycle. The reference clock should be stable before exiting this mode. Links are retrained after exiting this mode. Active Power Down - To enter the active power down mode, all ports are set by the power control system to idle state with some banks active. The PLL continues to run, and the reference clock remains stable. All peripheral circuitry is disabled to save power. No other operations are performed, so this mode should be exited before the next refresh cycle. Links are retrained after exiting this mode. Idle - When a link enters idle state, that link ceases to use power. The link is retrained when the link is brought back up. [0018] Figure 4 is a state diagram illustrating the power-down modes available to each bank in some embodiments. The bank is initially in a power on state. The bank then moves to a set all MRS state 4. In the set all MRS state 4 each component is sent a reset indication. The bank then moves to a precharge all state 41. In the precharge all state 41, the dynamic random access memory (DRAM) that composes the bank is precharged. The bank then moves to an idle state 4. If any link is active, then the bank moves to a self-refresh state 42, described above. If all links are inactive, the bank moves to a precharge power down state 4, also 4

5 7 EP B1 8 described above. If a refresh message (REF) is received while in the idle state, then the bank moves from the idle state to an auto refresh state 43 and to a precharge state 470. If an activation message (ACT) is received while in the idle state, then the bank moves from the idle state 4 to an active state 4. From the active state 4, if all links are down, then the bank moves to an active power down state 44, described above. From the active state 4, reads and writes are processed. When a read is received, the bank moves to a read state 4, and/or to a read auto precharge state 46. When a write is received, the bank moves to a write state and/or to a write auto precharge state 460. When the read or write is complete, the bank moves to a precharge state 470, and then back to the idle state 4. The bank continues this cycle until power is removed. [0019] Figure is a circuit diagram that illustrates the termination of the serial link. The host side of the link contains a termination detector 0, a differential driver, a beacon driver 1, and a termination circuit. The termination detector 0 detects when termination is in effect on the memory side of the link. The differential driver drives a differential signal over the positive and complementary lines of the serial link. The beacon driver 1 signals the memory side of the link that data is about to be transmitted so that the memory side of the link can engage the termination circuit 60. The memory side of the serial link contains a differential sampler 0, a beacon detector, and a termination circuit 60. The differential sampler 0 detects a differential voltage signal on the serial link. The beacon detector detects the beacon signal sent by the beacon driver 1. The termination circuit 60 terminates the link when the link is active. The termination resistor can be off when the link is inactive and on when the link is active. [00] The power control system can be used in a variety of environments such as memory devices or other environments that use serial memory. The power control system is particularly applicable to low-power applications such as cell phones, digital cameras, and other devices where battery life and power consumption are important concerns. [0021] From the foregoing, it will be appreciated that specific embodiments of the power control system have been described herein for purposes of illustration, but that various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims. Claims monitoring the transmission and reception of data on a plurality of serial ports (1-13) in a memory device using separate activity detection lines (14) each coupled to a corresponding serial port of the plurality of serial ports; determining if any serial port of the plurality of serial ports is inactive for data transmission and reception based, at least in part, on the activity detection line for the serial port; for each of the monitored plurality of serial ports, detecting when a shut-off criteria is satisfied at the serial port, the shut-off criteria including a period of inactivity for data transmission and reception at the serial port; and when the shut-off criteria is satisfied at any serial port of the plurality of serial ports, selectively powering down the each serial port meeting the shut-off criteria without affecting the operation of the plurality of other serial ports of the memory device; and upon determining that data transmission and reception has ceased for all of the plurality of serial ports of the memory device for a threshold period based, at least in part, on the activity detection lines for the plurality of serial ports, performing one or more of switching off core power to the memory device or switching off a clock generator to the memory device. 2. The method of claim 1 wherein powering down the each serial port comprises one or more of removing termination from the serial port, removing the clock signal from the serial port, or removing power from the serial port. 3. The method of claim 1 further comprising: upon detecting a transmission to any serial port of the plurality of serials ports that has been powered down, powering up the serial port to receive the transmission; and upon detecting a differential voltage applied to any serial port of the plurality of serials ports that has been powered down, powering up the serial port. 4. The method of claim 1 wherein a clock for operating each of the plurality of serial ports of the memory device is provided by a phased-locked loop.. The method of claim 1 wherein each of the plurality of ports is coupled to one of a plurality of memory banks of the memory device. 1. A method of progressively reducing power consumption in a multi-port memory device having a plurality of serial ports, the method comprising: 6. The method of claim 1 wherein the shut-off criteria is further includes a command received from a host, wherein the command indicates that no data will be transferred for a time period.

6 9 EP B1 7. The method of claim 1 further comprising: power from the serial port. detecting when a power-on criteria is satisfied at any powered down serial port of the plurality of serial ports; and when the power-on criteria is satisfied at the powered down serial port, selectively powering up the serial port without affecting the operation of the plurality of other serial ports of the memory device. 8. The method of claim 7, wherein the power-on criteria for a serial port includes detection of a change in a signal state on the detection line for the serial port. 9. A power control system for progressively reducing the power consumption of a memory device having a plurality of serial ports, comprising: power control logic (160) configured to detect the activity of each of a plurality of serial ports (1-13) of the memory device using a separate activity detection line (14) for each of the serial ports, the power control logic to determine if a shut-off criteria for any of the plurality of serial ports is satisfied based, at least in part, on inactivity of the serial port for data transmission and reception for a timeout period; a port power-down component (170-17) coupled to the power control logic and configured to selectively power down each serial port of the memory device based on the shutoff criteria for each serial port; and a core power control component (16) coupled to the power control logic and configured to power down core circuitry of the serial port memory device in response to detected inactivity in data transmission and reception on all the plurality of serial ports for a threshold time period.. The system of claim 9 wherein powering down each serial port comprises removing a termination from the port. 11. The system of claim 9, further comprising a clock line (1) for each serial port to carry a clock signal, wherein the port power-down component for each serial port is a clock switch (170) coupled to the clock line for the serial port, and wherein powering down each serial port comprises removing the clock signal from the serial port. 12. The system of claim 9, further comprising a power line (1) for each serial port to provide power to the serial port, wherein the port power-down component for each serial port is a power switch (17) coupled to the power line for the serial port, and wherein powering down each serial port comprises removing The system of claim 9 wherein the core circuitry includes one or more of: circuitry that provides core power to the memory device; or a clock generator for the memory device. 14. The system of claim 9 wherein the power control logic is further configured to selectively power up any powered down serial port of the plurality of serial ports of the memory device upon detecting activity on the activity detection line of the serial port. Patentansprüche 1. Verfahren zum fortschreitenden Reduzieren des Energieverbrauchs in einer Speichervorrichtung mit mehreren Ports, wobei das Verfahren aufweist: Überwachen der Übertragung und des Empfangs von Daten auf einer Mehrzahl von seriellen Ports (1-13) in einer Speichervorrichtung unter Verwendung von separaten Aktivitätsdetektionsleitungen (14), wobei jede mit einem zugehörigen seriellen Port der Mehrzahl von seriellen Ports verbunden ist; Ermitteln, ob irgendein serieller Port der Mehrzahl von seriellen Ports für eine Datenübertragung oder einen Datenempfang inaktiv ist, basierend, zumindest teilweise, auf der Aktivitätsdetektionsleitung für den seriellen Port; für jeden der überwachten seriellen Ports, Detektieren, wenn ein Abschaltkriterium an dem seriellen Port erfüllt ist, wobei das Abschaltkriterium eine Inaktivitätsdauer für die Datenübertragung und den Datenempfang an dem seriellen Port aufweist; und wenn das Ausschaltkriterium für irgendeinen seriellen Port der Mehrzahl von seriellen Ports erfüllt ist, selektives Ausschalten jedes seriellen Ports, der das Abschaltkriterium erfüllt, ohne den Betrieb der Mehrzahl von anderen seriellen Ports der Speichervorrichtung zu beeinflussen; und wenn ermittelt wird, dass die Datenübertragung und der Datenempfang für alle seriellen Ports der Speichervorrichtung für eine Schwellendauer aufgehört hat, basierend, zumindest teilweise, auf den Aktivitätsdetektionsleitungen für die Mehrzahl von seriellen Ports, Durchführen von einem oder mehreren aus Abschalten der Grundenergiezufuhr zu der Speichervorrichtung oder Abschalten eines Taktgenerators der Speichervorrichtung. 6

7 11 EP B Verfahren gemäß Anspruch 1, wobei Ausschalten jedes seriellen Ports ein oder mehreres aus Entfernen der Endenabschlusses des seriellen Ports, Entfernen des Taktsignals von dem seriellen Port oder Entfernen der Stromversorgung von dem seriellen Port aufweist. 3. Verfahren gemäß Anspruch 1, ferner aufweisend: Bei Detektieren einer Übertragung an irgendeinen seriellen Port der Mehrzahl von seriellen Ports, der ausgeschaltet wurde, Anschalten des seriellen Ports zum Empfangen der Übertragung und bei Detektieren, dass irgendeinem seriellen Port der Mehrzahl von seriellen Ports, der ausgeschaltet wurde, eine differentielle Spannung zugeführt wird, Anschalten des seriellen Ports. 4. Verfahren gemäß Anspruch 1, wobei ein Takt zum Betreiben jedes der Mehrzahl von seriellen Ports der Speichervorrichtung von einer Phasenregelschleife bereitgestellt wird.. Verfahren gemäß Anspruch 1, wobei jeder der Mehrzahl von Ports mit einer Mehrzahl von Speicherbänken der Speichervorrichtung gekoppelt ist. 6. Verfahren gemäß Anspruch 1, wobei das Abschaltkriterium ferner einen von einem Host empfangenen Befehl aufweist, wobei der Befehl angibt, dass keine Daten für eine Zeitdauer übertragen werden. 7. Verfahren gemäß Anspruch 1 ferner aufweisend: Detektieren, wenn ein Anschaltkriterium an irgendeinem ausgeschalteten seriellen Port der Mehrzahl von seriellen Ports erfüllt ist; und wenn das Anschaltkriterium an dem ausgeschalteten seriellen Port erfüllt ist, selektives Anschalten des seriellen Ports ohne den Betrieb der Mehrzahl von anderen seriellen Ports der Speichervorrichtung zu beeinflussen. 8. Verfahren gemäß Anspruch 7, wobei das Anschaltkriterium für einen seriellen Port das Detektieren einer Änderung des Signalzustands auf der Detektionsleitung für den seriellen Port aufweist. 9. Energiesteuersystem zum fortschreitenden Reduzieren des Energieverbrauchs einer Speichervorrichtung mit mehreren Ports aufweisend: eine Energiesteuerlogik (160) eingerichtet zum Detektieren der Aktivität jedes einer Mehrzahl von seriellen Ports (1-13) der Speichervorrichtung unter Verwendung einer separaten Aktivitätsdetektionsleitung (14) für jeden der seriellen Ports, wobei die Energiesteuerlogik ermittelt, ob ein Abschaltkriterium für irgendeinen der Mehrzahl von seriellen Ports erfüllt ist, zumindest teilweise basierend auf der Inaktivität des seriellen Ports für Datenübertragung und Datenempfang für eine Zeitüberschreitungsdauer; eine Port-Ausschaltkomponente (170-17), die mit der Energiesteuerlogik gekoppelt ist und eingerichtet ist, jeden seriellen Port der Speichervorrichtung basierend auf dem Abschaltkriterium für jeden seriellen Port auszuschalten; und eine Grundenergiesteuerkomponente (16), die mit der Energiesteuerlogik gekoppelt ist und eingerichtet ist, eine Kernschaltung der Serielle- Ports-Speichervorrichtung in Antwort auf die detektierte Inaktivität bei der Datenübertragung und dem Datenempfang auf allen der Mehrzahl von seriellen Ports für eine Schwellenzeitdauer auszuschalten.. System gemäß Anspruch 9, wobei Ausschalten jedes seriellen Ports Entfernen des Endenabschlusses des Ports aufweist. 11. System gemäß Anspruch 9, ferner aufweisend eine Taktleitung (1) für jeden seriellen Port zum Führen eine Taktsignals, wobei die Port-Ausschaltkomponente für jeden seriellen Port ein Taktschalter (170) ist, der mit der Taktleitung für den seriellen Port gekoppelt ist, und wobei Ausschalten eines seriellen Ports Entfernen des Taktsignals von dem seriellen Port aufweist. 12. System gemäß Anspruch 9, ferner aufweisend eine Energieleitung (1) für jeden seriellen Port zum Bereitstellen von Energie für den seriellen Port, wobei die Port-Ausschaltkomponente für jeden seriellen Port ein Energieschalter (17) ist, der mit der Energieleitung für den seriellen Port verbunden ist, und wobei Ausschalten eines seriellen Ports Entfernen der Energie von dem seriellen Port aufweist. 13. System gemäß Anspruch 9, wobei die Kernschaltung eines oder mehrere aufweist von: einer Schaltung, die der Speichervorrichtung Grundenergie bereitstellt; oder einem Taktgenerator für die Speichervorrichtung. 14. System gemäß Anspruch 9, wobei die Energiesteuerlogik ferner eingerichtet ist, selektiv jeden seriellen Port der Mehrzahl von seriellen Ports der Speichervorrichtung einzuschalten, wenn auf der Aktivitätsdetektionsleitung des seriellen Ports Aktivität detektiert wird. 7

8 13 EP B1 14 Revendications la mise sous tension du port série. 1. Procédé de réduction progressive de la consommation de puissance dans un dispositif de mémoire multiport ayant une pluralité de ports série, le procédé comprenant : 4. Procédé selon la revendication 1, dans lequel une horloge pour faire fonctionner chacun de la pluralité de ports série du dispositif de mémoire est fournie par une boucle à phase asservie. la surveillance de la transmission et de la réception de données sur une pluralité de ports série (1-13) dans un dispositif de mémoire en utilisant des lignes de détection d activité distinctes (14) chacune couplée à un port série correspondant de la pluralité de ports série ; la détermination de si un quelconque port série de la pluralité de ports série est inactif pour la transmission et la réception de données sur la base, au moins en partie, de la ligne de détection d activité pour le port série ; pour chacun de la pluralité de ports série surveillée, la détection de quand un critère d arrêt est satisfait au niveau du port série, le critère d arrêt comprenant une période d inactivité pour la transmission et la réception de données au niveau du port série ; et lorsque le critère d arrêt est satisfait au niveau d un quelconque port série de la pluralité de ports série, la mise hors tension sélective de chaque port série remplissant le critère d arrêt sans affecter le fonctionnement de la pluralité d autres ports série du dispositif de mémoire ; et lors de la détermination selon laquelle la transmission et la réception de données a cessé pour la totalité de la pluralité de ports série du dispositif de mémoire pendant une période seuil sur la base, au moins en partie, des lignes de détection d activité pour la pluralité de ports série, l exécution d un ou plusieurs parmi le blocage de la puissance de coeur vers le dispositif de mémoire ou le blocage d un générateur d horloge vers le dispositif de mémoire Procédé selon la revendication 1, dans lequel chacun de la pluralité de ports est couplé à un d une pluralité de bancs de mémoire du dispositif de mémoire. 6. Procédé selon la revendication 1, dans lequel le critère d arrêt comprend en outre une commande reçue d un hôte, dans lequel la commande indique qu aucune donnée ne sera transférée pendant une période de temps. 7. Procédé selon la revendication 1, comprenant en outre : la détection de quand un critère de mise sous tension est satisfait au niveau d un quelconque port série mis hors tension de la pluralité de ports série ; et lorsque le critère de mise sous tension est satisfait au niveau du port série mis hors tension, la mise sous tension sélective du port série sans affecter le fonctionnement de la pluralité d autres ports série du dispositif de mémoire. 8. Procédé selon la revendication 7, dans lequel le critère de mise sous tension pour un port série comprend la détection d un changement d un état de signal sur la ligne de détection pour le port série. 9. Système de commande de puissance pour réduire progressivement la consommation de puissance d un dispositif de mémoire ayant une pluralité de ports série, comprenant : 2. Procédé selon la revendication 1, caractérisé en ce que la mise hors tension dudit chaque port série comprend un ou plusieurs parmi la suppression de la terminaison du port série, la suppression du signal d horloge du port série, ou la suppression de la puissance du port. 3. Procédé selon la revendication 1, comprenant en outre : lors de la détection d une transmission à un quelconque port série de la pluralité de ports série qui a été mis hors tension, la mise sous tension du port série pour recevoir la transmission ; et lors de la détection d une tension différentielle appliquée à un quelconque port série de la pluralité de ports série qui a été mis hors tension, 4 0 une logique de commande de puissance (160) configurée pour détecter l activité de chacun d une pluralité de ports série (1-13) du dispositif de mémoire en utilisant une ligne de détection d activité distincte (14) pour chacun des ports série, la logique de commande de puissance destinée à déterminer si un critère d arrêt pour l un quelconque de la pluralité de ports série est satisfait sur la base, au moins en partie, de l inactivité du port série pour la transmission et la réception de données pendant une période de temporisation ; un composant de mise hors tension de port (170-17) couplé à la logique de commande de puissance et configuré pour mettre hors tension sélectivement chaque port série du dispositif de mémoire sur la base du critère d arrêt pour cha- 8

9 1 EP B1 16 que port série ; et un composant de commande de puissance de coeur (16) couplé à la logique de commande de puissance et configuré pour mettre hors tension un ensemble de circuits de coeur du dispositif de mémoire à port série en réponse à l inactivité détectée dans la transmission et la réception de données sur la totalité de la pluralité de ports série pendant une période de temps seuil.. Système selon la revendication 9, dans lequel la mise hors tension de chaque port série comprend la suppression d une terminaison du port. 11. Système selon la revendication 9, comprenant en outre une ligne d horloge (1) pour chaque port série pour acheminer un signal d horloge, dans lequel le composant de mise hors tension de port pour chaque port série est un commutateur d horloge (170) couplé à la ligne d horloge pour le port série, et dans lequel la mise hors tension de chaque port série comprend la suppression du signal d horloge du port série Système selon la revendication 9, comprenant en outre une ligne de puissance (1) pour chaque port série pour fournir de la puissance au port série, dans lequel le composant de mise hors tension de port pour chaque port série est un commutateur de puissance (17) couplé à la ligne de puissance pour le port série, et dans lequel la mise hors tension de chaque port série comprend la suppression de la puissance du port série Système selon la revendication 9, dans lequel l ensemble de circuits de coeur comprend un ou plusieurs parmi : 3 un ensemble de circuits qui fournit de la puissance de coeur au dispositif de mémoire ; ou un générateur d horloge pour le dispositif de mémoire. 14. Système selon la revendication 9, dans lequel la logique de commande de puissance est en outre configurée pour mettre sous tension sélectivement un quelconque port série mis hors tension de la pluralité de ports série du dispositif de mémoire lors de la détection d activité sur la ligne de détection d activité du port série

10 EP B1

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15 EP B1 REFERENCES CITED IN THE DESCRIPTION This list of references cited by the applicant is for the reader s convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard. Patent documents cited in the description EP A2 [0004] EP A2 [000] US A [0008] 1