Lsi Corporation

Lsi Logic Corporation

Thomas Hughes

Cheng-Gang Kong

Terence J Magee

Hui-Yin Seto

Derrick Sai-Tang Butt

Victor K Suen

Transmitter-based techniques are provided for compensation of intersymbol interference and/or simultaneous switching outputs, using selective pulse width modulation. One or more signals are transmitted by detecting whether one or more of said signals satisfy one or more predefined signal corruption conditions, wherein said predefined signal corruption conditions indicate that one or more of said signals are anticipated to exhibit one or more of intersymbol interference and simultaneous switching outputs; and selecting a delay for one or more of the signals based on the one or more predefined signal corruptions conditions. The predefined signal corruption conditions comprise, for example, (i) digital data encoded in the one or more signals maintaining a same binary value for two or more consecutive clock cycles (to indicate intersymbol interference); and (ii) a predefined minimum number of aggressor data edges in digital data encoded in the one or more signals, and a corresponding predefined number of victim data edges in the digital data encoded in the one or more signals, wherein the victim edges are moving in an opposite direction to the aggressor data edges (to indicate simultaneous switching outputs).

Methods and apparatus for transmitting signals with selective delay for compensation of intersymbol interference and simultaneous switching outputs

A memory interface physical layer macro including one or more embedded input/output (I/O) buffers, one or more memory interface hardmacros and control logic. The one or more embedded input/output (I/O) buffers support a plurality of I/O supply voltage levels. The one or more memory interface hardmacros are coupled to the one or more embedded I/O buffers. The control logic controls the one or more hardmacros and the one or more I/O buffers.

Multiple memory standard physical layer macro function

Apparatus and systems for improved PVT invariant fast rank switching in a DDR3 memory subsystem. A clock skew control circuit is provided between a memory controller and a DDR3 SDRAM memory subsystem to adjust skew between the DDR3 clock signal and data related signals (e.g., DQ and/or DQS). A initial write-leveling procedure determines the correct skew and programs a register file in the skew adjustment circuit. The register file includes a register for each of multiple ranks in the DDR3 memory. The values in each register serve to control selection of alignment of the data related signals to align with one of multiple phase shifted versions of a 1&#xd7; DDR3 clock signal. The phase shifted clock signals are generated by clock divider circuits from a 2&#xd7; DDR clock signal and use of a single fixed delay line approximating &#x215b; of a 1&#xd7; DDR3 clock period.

Apparatus and systems for VT invariant DDR3 SDRAM write leveling

The present invention is a method of asynchronous clock regeneration. The method includes synchronizing a first write pointer and a second write pointer, the first write pointer being an offline write pointer, the second write pointer being an online write pointer. The method further includes swapping at least one bit from the first write pointer with at least one bit of the second write pointer when the bits are static. The method further includes regenerating a DQS (Data Strobe Signal) clock.

System and method for asynchronous clock regeneration

A method for glitch-free updates of a standard cell-based programmable delay including the steps of (A) generating an output signal in response to an input signal and a plurality of first control signals and (B) generating the plurality of first control signals in response to the output signal and a plurality of second control signals. The output signal may include a delayed version of the input signal. An amount of delay between the input signal and the output signal may be determined based upon the plurality of first control signals.

System for glitch-free delay updates of a standard cell-based programmable delay

The present invention is a method for data path voltage and temperature compensation. The method includes configuring an offline data path to match an online data path. The method further includes compensating the offline data path for voltage and temperature variation. The method further includes swapping the offline data path with the online data path. Further, swapping occurs automatically without interruption of data flow along the data paths.

System and method for providing swap path voltage and temperature compensation

The present invention is directed to a method for compensating for process, voltage, and temperature variation without complex online/offline swapping of data paths requiring a dedicated FIFO(First-in First-out) buffer design. Delay cells are trained for each clock path (namely a Functional delay) and a spare delay cell is trained. A ratio is calculated for each Functional delay cell by dividing the Functional delay cells' setting into the spare delay cells' one-fourth cycle setting. These ratios reflect any process variation. Functional mode is then entered and a Master-Slave approach switched to, during which the spare delay cell repeats the training sequence continuously while the Functional delay cells delay the clocks from the RAM(Random Access Memory). Each Functional delay cell is updated at the end of each training sequence of the spare delay cell, compensating for voltage and temperature change, by dividing the ratio into the new spare delay cell one-fourth cycle setting.

System and method for compensating for PVT variation effects on the delay line of a clock signal

A method for providing programmable delay read data strobe gating with voltage and temperature compensation. The method includes receiving a training request. The method further includes calibrating programmable delay lines for operating frequency and voltage and temperature variation. The method further includes locking to a first feedback signal. The method further includes storing a first feedback lock setting corresponding to the locked-to first feedback signal. The method further includes granting the training request. Additionally, when training is completed, the method further includes recalibrating the programmable delay lines for operating frequency and voltage and temperature variation.

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San Francisco, CA, United States of America

Thomas Hughes