Patent application number | Description | Published |
20080238534 | PHASE SHIFTING IN DLL/PLL - The disclosure relates to phase shifting in Delay Locked Loops (DLLs) and Phase-Locked Loops (PLLs). A charge pump in the DLL or PLL includes a capacitor connected in parallel to an output node. A primary current switching circuit charges the capacitor with a source current and discharges the capacitor with a sink current. A supplemental source circuit sources a positive phase shift producing current which has a range of magnitudes. A magnitude of the positive phase shift producing current is determined by at least one source selection signal. A supplemental sink circuit for sources a negative phase shift producing current which has a range of magnitudes. A magnitude of the negative phase shift producing current is determined by at least one sink selection signal. | 10-02-2008 |
20080252344 | TIMING VERNIER USING A DELAY LOCKED LOOP - A method for synchronizing a plurality of programmable timing verniers with a reference pulse signal, each of the verniers being programmable to one of a plurality of timing steps within a delay range determined by a control signal applied to a bias input. A first and second control vernier is selected from the plurality of verniers, the first control vernier is programmed to a first delay, and the second control vernier is programmed to a second delay. The first and second control verniers are triggered together to generate respective first and second delay signals. A difference pulse signal is generated with a duty cycle corresponding to a difference between the generated first delay signal and second delay signal. The duty cycle of the pulse signal is compared to a duty cycle of the reference pulse signal to generate a difference signal pulse. The difference signal pulse is coupled to the bias input of the verniers to adjust the delay range, such that the duty cycle of the difference signal approaches the duty cycle of the reference pulse signal. In one embodiment there is provided a circuit for implementing the method. | 10-16-2008 |
20080303546 | DYNAMIC IMPEDANCE CONTROL FOR INPUT/OUTPUT BUFFERS - A system and method of performing off chip drive (OCD) and on-die termination (ODT) are provided. A common pull-up network composed of transistors and a common pull-down network composed of transistors are employed to implement both of these functions. In drive mode, the pull-up network is configured to produce a calibrated drive impedance when an “on” output is to be generated, and the pull-up network is configured to produce a calibrated drive impedance when an “off” output is to be generated. In termination mode, the pull-up network and the pull-down network are configured to produce a calibrated pull-up resistance and pull-down resistance respectively such that together, they form a split termination. | 12-11-2008 |
20100097869 | MEMORY SYSTEM HAVING INCORRUPTED STROBE SIGNALS - A memory system circuit and method therefor are disclosed. The circuit is adapted to detect a transition in a data timing signal from an indeterminate logic level to a selected one of a high logic level and a low logic level. The circuit includes a comparator having a first input, a second input and an output. The first and second inputs receive the data timing signal and a reference voltage respectively. The output changes logic levels in response to a change in polarity of a voltage difference between the voltage of the timing signal and the reference voltage. The reference voltage is sufficiently closer to the selected one of the logic levels as compared to the other of the logic levels so as to at least substantially prevent potential false positive detections. | 04-22-2010 |
20100117698 | TIMING VERNIER USING A DELAY LOCKED LOOP - A method for synchronizing a plurality of programmable timing verniers with a reference pulse signal, each of the verniers being programmable to one of a plurality of timing steps within a delay range determined by a control signal applied to a bias input. A first and second control vernier is selected from the plurality of verniers, the first control vernier is programmed to a first delay, and the second control vernier is programmed to a second delay. The first and second control verniers are triggered together to generate respective first and second delay signals. A difference pulse signal is generated with a duty cycle corresponding to a difference between the generated first delay signal and second delay signal. The duty cycle of the pulse signal is compared to a duty cycle of the reference pulse signal to generate a difference signal pulse. The difference signal pulse is coupled to the bias input of the verniers to adjust the delay range, such that the duty cycle of the difference signal approaches the duty cycle of the reference pulse signal. In one embodiment there is provided a circuit for implementing the method. | 05-13-2010 |
20100268906 | HIGH BANDWIDTH MEMORY INTERFACE - This invention describes an improved high bandwidth chip-to-chip interface for memory devices, which is capable of operating at higher speeds, while maintaining error free data transmission, consuming lower power, and supporting more load. Accordingly, the invention provides a memory subsystem comprising at least two semiconductor devices; a main bus containing a plurality of bus lines for carrying substantially all data and command information needed by the devices, the semiconductor devices including at least one memory device connected in parallel to the bus; the bus lines including respective row command lines and column command lines; a clock generator for coupling to a clock line, the devices including clock inputs for coupling to the clock line; and the devices including programmable delay elements coupled to the clock inputs to delay the clock edges for setting an input data sampling time of the memory device. | 10-21-2010 |
20110043246 | DYNAMIC IMPEDANCE CONTROL FOR INPUT/OUTPUT BUFFERS - A system and method of performing off chip drive (OCD) and on-die termination (ODT) are provided. A common pull-up network composed of transistors and a common pull-down network composed of transistors are employed to implement both of these functions. In drive mode, the pull-up network is configured to produce a calibrated drive impedance when an “on” output is to be generated, and the pull-up network is configured to produce a calibrated drive impedance when an “off” output is to be generated. In termination mode, the pull-up network and the pull-down network are configured to produce a calibrated pull-up resistance and pull-down resistance respectively such that together, they form a split termination. | 02-24-2011 |
20110063006 | TIMING VERNIER USING A DELAY LOCKED LOOP - A method for synchronizing a plurality of programmable timing verniers with a reference pulse signal, each of the verniers being programmable to one of a plurality of timing steps within a delay range determined by a control signal applied to a bias input. A first and second control vernier is selected from the plurality of verniers, the first control vernier is programmed to a first delay, and the second control vernier is programmed to a second delay. The first and second control verniers are triggered together to generate respective first and second delay signals. A difference pulse signal is generated with a duty cycle corresponding to a difference between the generated first delay signal and second delay signal. The duty cycle of the pulse signal is compared to a duty cycle of the reference pulse signal to generate a difference signal pulse. The difference signal pulse is coupled to the bias input of the verniers to adjust the delay range, such that the duty cycle of the difference signal approaches the duty cycle of the reference pulse signal. | 03-17-2011 |
20120019282 | DYNAMIC IMPEDANCE CONTROL FOR INPUT/OUTPUT BUFFERS - A system and method of performing off chip drive (OCD) and on-die termination (ODT) are provided. A common pull-up network composed of transistors and a common pull-down network composed of transistors are employed to implement both of these functions. In drive mode, the pull-up network is configured to produce a calibrated drive impedance when an “on” output is to be generated, and the pull-up network is configured to produce a calibrated drive impedance when an “off” output is to be generated. In termination mode, the pull-up network and the pull-down network are configured to produce a calibrated pull-up resistance and pull-down resistance respectively such that together, they form a split termination. | 01-26-2012 |
20120176118 | VOLTAGE DOWN CONVERTER FOR HIGH SPEED MEMORY - A voltage down converter (VDC) applicable to high-speed memory devices. The VDC includes a steady driver and active driver along with at least one additional transistor. The steady driver and active driver are coupled by a transistor switch during device start-up to provide fast ramp-up to operating voltage and current. After start-up, the steady driver and active drive function to maintain a steady operating voltage and current. An additional transistor is digitally controlled to drive up operating voltage and current upon issuance of an active command representing read, write, and/or refresh of memory. In this manner, the additional transistor provides fast compensation for fluctuations in operating voltage and current brought on by activity in the memory array. | 07-12-2012 |
20130132761 | MEMORY MODULE INCLUDING A PLURALITY OF SYNCHRONOUS MEMORY DEVICES - A memory module that includes a buffer and a plurality of synchronous memory devices. The memory module also includes bidirectional bus lines, and each of the synchronous memory devices has bidirectional data terminals. The buffer is configured to regenerate signals received on the bus lines for receipt by the synchronous memory devices, and to regenerate signals received from any one of the synchronous memory devices for receipt by the bus lines. The memory module may further include command lines and a clock line for providing commands and a clock signal to the synchronous memory devices via a command buffer. The combined data bus width of the memory module may be greater than the data bus width of any single one of synchronous memory device, and the total address space provided by the memory module may be larger than the data space for any single synchronous memory device. | 05-23-2013 |
20130329482 | HIGH BANDWIDTH MEMORY INTERFACE - A memory module that includes a buffer and a plurality of synchronous memory devices. The memory module also includes bidirectional bus lines, and each of the synchronous memory devices has bidirectional data terminals. The buffer is configured to regenerate signals received on the bus lines for receipt by the synchronous memory devices, and to regenerate signals received from any one of the synchronous memory devices for receipt by the bus lines. The memory module may further include command lines and a clock line for providing commands and a clock signal to the synchronous memory devices via a command buffer. The combined data bus width of the memory module may be greater than the data bus width of any single one of synchronous memory device, and the total address space provided by the memory module may be larger than the data space for any single synchronous memory device. | 12-12-2013 |
20140071781 | VOLTAGE DOWN CONVERTER FOR HIGH SPEED MEMORY - A voltage down converter (VDC) applicable to high-speed memory devices. The VDC includes a steady driver and active driver along with at least one additional transistor. The steady driver and active driver are coupled by a transistor switch during device start-up to provide fast ramp-up to operating voltage and current. After start-up, the steady driver and active drive function to maintain a steady operating voltage and current. An additional transistor is digitally controlled to drive up operating voltage and current upon issuance of an active command representing read, write, and/or refresh of memory. In this manner, the additional transistor provides fast compensation for fluctuations in operating voltage and current brought on by activity in the memory array. | 03-13-2014 |
20150078057 | HIGH BANDWIDTH MEMORY INTERFACE - A memory module that includes a buffer and a plurality of synchronous memory devices. The memory module also includes bidirectional bus lines, and each of the synchronous memory devices has bidirectional data terminals. The buffer is configured to regenerate signals received on the bus lines for receipt by the synchronous memory devices, and to regenerate signals received from any one of the synchronous memory devices for receipt by the bus lines. The memory module may further include command lines and a clock line for providing commands and a clock signal to the synchronous memory devices via a command buffer. The combined data bus width of the memory module may be greater than the data bus width of any single one of synchronous memory device, and the total address space provided by the memory module may be larger than the data space for any single synchronous memory device. | 03-19-2015 |