Abstract: A circuit arrangement to recover clock and data from a received signal comprises an electronic commutator for sampling the received signal in such a way that several sampling values of a bit cell transmitted with the received signal are distributed time-wise one after the other onto several output connections of the commutator device and emitted there in the form of corresponding intermediate signals. A first circuit combines a first group of intermediate signals of the commutator device into a first uniting signal, which serves as the basis for data recovery or comprises the recovered data signal, while a second circuit combines a second group of intermediate signals of the commutator device into a second uniting signal, which serves as the basis for clock recovery. The second uniting signal is fed to a phase regulator arrangement, which, dependent on this, sets the sampling phases assigned to the individual output connections of the commutator device.

Abstract: One embodiment of the present invention provides to a memory device adapted to receive data according to a write clock signal and to output data according to a read clock signal, comprising a clock port configured to output the read clock signal and to receive the write clock signal and a serial bidirectional driver configured to output the read clock signal via the clock port and to receive the write clock signal via the clock port simultaneously.

Abstract: The present invention relates to a memory system having a memory device with two clock lines. One embodiment of the present invention provides a memory system comprising at least one memory device, a memory controller to control operation of the memory device, a first clock line which extends from a write clock output of the memory controller to a clock port of the memory device to provide a clock signal to the memory device, and a second clock line which extends from the clock port of the memory device to a read clock input of the memory controller to forward the clock signal applied to the clock port of the memory device back to a read clock input of the memory controller. The memory device may further comprise a synchronization circuit adapted to receive the clock signal from the memory controller and to, provide an output data synchronized to the forwarded clock signal.

Abstract: Method for sampling phase control for clock and data recovery of a data signal includes sampling a received data signal with a first sampling signal comprising equidistant sampling pulses, minimizing phase deviation between the first sampling signal and the phase of the received data signal to generate an adjusted second sampling signal, and sampling the received data signal with the adjusted second sampling signal to generate sampling data values. The method also includes integrating the sampling data values of the sampled data signal to form a summation value, and altering the phase of sampling pulses of the adjusted second sampling signal until the integrated summation value exceeds a threshold value that can be set.

Abstract: In a semiconductor memory system having a loop forward architecture, the command, address and write data stream and the separate read data stream in form of protocol-based frames transmitted to/from memory chips in the following order: memory controller to the first memory chip, to the second memory chip, to the third memory chip and to the fourth memory chip and the read data stream is transferred from the fourth memory chip to the memory controller. With each command usually one of four memory chips is accessed for data processing, while three of four memory chips have only to fulfil a simple re-drive of CAwD stream and read data stream stream. By separately transferring a rank select signal not embedded in the frame from the memory controller to each memory chip a lot of more flexibility for these tasks can be achieved.

Abstract: The present invention includes a semiconductor memory modules and semiconductor memory systems using the same. The modules divide a conventional DIMM into a series of separate, smaller memory modules. Each memory module includes at least one semiconductor memory chip arranged on a substrate; CAwD signal input lines arranged on the substrate in a first predetermined line number and connecting one of the semiconductor memory chips to CAwD input signal pins on the substrate; and rD signal output lines arranged on the substrate in a second predetermined line number and connecting the one or a last semiconductor memory to a second number of rD output signal pins of the substrate. In a semiconductor memory system including the semiconductor memory modules, each memory module is separately connected to a memory controller by the CAwD signal input linesand the rD signal output lines in a respective point-to-point fashion.

Abstract: There is provided a method of operating a memory device comprising at least one memory module, a corresponding memory module and a memory device comprising the at least one memory module. It is proposed that in the memory module (100a, 100b, 100c, 100d) a command and write data signal (CA, WD) is received and a read data signal (RD) is transmitted from the memory module (100a, 100b, 100c, 100d). Further, an input clock signal (CLK) is received in the memory module (100a, 100b, 100c, 100d) and is regenerated by means of a clock synthesizer unit (150) of the memory module (100a, 100b, 100c, 100d) to produce a regenerated input clock signal of the memory module (100a, 100b, 100c, 100d). The read data signal (RD) transmitted from the memory module (100a, 100b, 100c, 100d) is synchronized to the regenerated input clock signal of the memory module (100a, 100b, 100c, 100d). For this purpose, the clock synthesizer unit (150) preferably comprises a phase-locked loop.

Abstract: A synchronous signal generator is provided that contains a first and second counting and delay circuit, which both are in a subhierarchical position with respect to a reset signal synchronization/delay circuit. The reset signal synchronization/delay circuit and the first and second counting and delay circuit are triggered by a basic clock signal or a first clock signal derived therefrom to be identical in frequency and phase, and contain counting means whose initial and final counting state are adjustable in order to set, in a clocked fashion, the temporal positions of a first and second load signal that are output by the first counting and delay circuit as well as of a FIFO read clock signal that is output by the second counting and delay circuit and thus adapt them to the temporal requirements of a semiconductor memory system containing the synchronous signal generator.

Abstract: The present invention relates to a semiconductor memory system including a memory controller transmitting high speed write data, command and address signal streams based on a predefined transmission protocol and a high speed write clock signal and for receiving serial high speed read data signals as signal frames based on the transmission protocol and a memory module which includes a plurality of semiconductor memory chips and a smart buffer chip which is different from prior art register chips because it forms a genuine high speed serial link including the complete digital function thereof such as protocol layer, error coding and so on. The smart buffer chip communicates with the memory chips by a low speed interface and through low speed point-to-point or fly-by connection lines.

Abstract: Provided is a semiconductor memory chip that includes a memory core and an interface circuit having decoding, selecting and scheduling circuit means for decoding from a signal frame a respective type of data signals, command signals and address signals, selection of actions which are required in the memory chip according to the respective signal type and scheduling the memory core and sections of the interface circuit respectively for the decoded signal. The interface circuit further comprises a CRC bit decoding and check unit and a protection circuit arranged for protecting the memory core and for enabling/disabling switching through of signal transfer from the interface circuit to the memory core depending on a correct/incorrect signal generated by the CRC bit decoding and check unit according to the result of checking an information within the frame by means of the CRC bits which are inserted in a signal frame in association to the respective information in accordance with a defined transmission protocol.

Abstract: A memory system and method is disclosed. In one embodiment, the memory system includes a memory controller and at least one memory module on which a certain number of semiconductor memory chips and connecting lines are arranged in a respectively specified topology. The connecting lines include first connecting lines forming transfer channels for a protocol based transfer of data and command signal streams from the memory controller to at least one of the memory chips on the memory module and from there to the memory controller, respectively. Second connecting lines are routed separately from the memory controller directly to at least one of the memory chips on the memory module for transferring select information to the at least one memory chip separately from the data and command signal streams.

Abstract: A memory buffer for a memory module board which is connected via a signal line (10-i) to a plurality of memory modules (2-i) mounted on said memory module board having different signal line lengths, wherein the memory buffer (1) comprises for each signal line (10-i) a corresponding integration circuit (18-i) for integrating the transmission time of a measurement pulse transmitted via said signal line (10-i) between said memory buffer (1) and a memory module (2-i) connected to said signal line (10-i).

Abstract: A high-speed interface circuit is implemented in a semiconductor memory chip including a memory core, a first interface circuit section, and a second interface circuit section. The first interface circuit section is connectable to a write data-/command and address signal bus, includes a write data-/command and address re-driver/transmitter path (which may be transparent) and does not include any clock signal synchronizing circuitry, and a main write signal path including a serial-to-parallel converting and synchronizing device to synchronize with a reference clock signal received write data-/command and address signals and delivering the parallel converted write signals to the memory core.

Abstract: In a line driver an input current (IINN) feeds a node (K1) which is connected to an input on an amplifier (OTA1). A further input on the amplifier (OTA1) has a reference voltage (VSGND) applied to it. The amplifier (OTA1) controls a current source (MN1) which outputs an output current (IOUTN). A current/voltage converter (R1) is connected between the node (K1) and the current source (MN1). A voltage/current converter (R2) is connected between the current source (MN1) and a ground (VSS).

Abstract: A control unit is set up to generate and output periodic clock signals, that are in sync with and at the same frequency as a periodic basic clock that is input into it, and periodic control signals, that are likewise in sync with the basic clock, and to turn on/turn off output of at least the clock signal in reaction to an activation/deactivation signal, which is routed to it externally, to a synchronous parallel/serial converter executing synchronization and serialization of a parallel data signal with the basic clock. Whereas output of the clock signal and optionally of the control signals are turned off, immediately after the activation/deactivation signal has assumed its deactivation state, the control unit is able to synchronize turning control signals on again, when the activation/deactivation signal has assumed its activation state.

Abstract: A CDR circuit arrangement, for example for a transceiver module, features a data recovery unit (4) for the recovery of the data contained in a received signal (DATA) by scanning this received data signal, and a phase evaluation unit for the determination of a suitable phase position for the scanning carried out by the data recovery unit (4).

Abstract: A synchronization and data recovery device (SuD) for clock-synchronized recovery of data bits in a data stream is provided, which is particularly suitable for improved backward identification of data in serial receiver interfaces of high-speed semiconductor memory modules and/or memory controller modules with a low data density. The SuD includes a sampling unit, a data adjustment unit, a digital monitoring unit, a phase lock detector unit, a phase generator, an FIR low-pass filter and a data recovery decision unit. After synchronization of the values that have been sampled by the sampling unit in the data adjustment unit, these values are filtered in the FIR low-pass filter unit, which indicates a greater tolerance with respect to fluctuations in the ideal sampling time, in that it uses sample values of the previous symbol and of the subsequent symbol in addition to the sample values of the symbol to be identified.

Abstract: To reconstruct data transmitted over a transmission path, for example a cable, the corresponding signal received by the receiver is firstly amplified and subsequently made discrete by means of an A/D-converter (6), in order to obtain a suitable digital signal, whereby the signal amplified for this purpose is scanned with a relatively low sampling rate, which can frequently lie in the Nyquist range or can be even less than the Nyquist frequency. Subsequently the signal made discrete in this way is filtered by means of a digital high pass filter (8) and equalized by means of a digital cable approximation filter (9) to compensate any distortion occurring during the transmission over the transmission path. By means of a phase locked loop (14, 18) a regenerated clock (CLK) and synchronous with this clock the originally transmitted data (DATA) is recovered from the digital signal processed in this way.

Abstract: A synchronous parallel/serial converter is disclosed. In one embodiment, the a synchronous parallel/serial converter that receives a parallel n-bit input signal and comprising a first shift register that receives an odd-numbered part of the input signal with a first load signal in synchronism with a clock signal having a clock rate half the clock rate of a system clock, and provides a serial output as a first one-bit signal sequence; a second shift register that receives an even-numbered part of the input signal with a second load signal synchronism with the clock signal and provides a serial output as a second one-bit signal sequence; and a fusion unit that fuses the first serial one-bit signal sequence synchronously with the clock signal and the second serial one-bit signal sequence in synchronism the clock signal to form a serial one-bit output signal.

Abstract: One embodiment of the present invention provides a memory device comprising an array of memory cells, a control logic for writing data to and reading data from the array of memory cells, the control logic comprising a first interface, an input/output section for exchanging data, address and control signals with a circuit external to the memory device, the input/output section comprising a second interface for sending signals to and receiving signals from the first interface of the control logic, and a synchronizing facility connected to the first interface of the control logic and to the second interface of the input/output section for synchronizing the first interface of the control logic and the second interface of the input/output section.