Cavium, Inc.

Advanced Micro Devices Corporation

Synopsys, Inc.

David Da-Wei Lin

Edward Wade Thoenes

Prasant Kumar Vallur

Vladimir Zlatkovic

Thucydides Xanthopoulos

Srikanth Reddy Gruddanti

Kuan Zhou

Vasudevan Kandadi

Manoj N Kulkarni

Abdelrahman Alaa Gouda

Alexander A Alexeyev

Shefali Walia

Priyadarshi Saxena

Youssef Mamdouh El-Toukhy

A signal processing circuit includes an analog front-end circuit and a digital delay circuit. The analog circuit receives a clock signal and provides a compensated clock signal. The digital delay circuit is coupled to the analog front-end circuit and provides a compensated sample clock signal in response to delaying the compensated clock signal. The analog circuit measures a variation of a power supply voltage and adjusts a gain through the analog circuit according to a measured variation of the power supply voltage.

Jitter reduction in mixed-signal processing circuits

Duty cycle adjustment circuitry includes a first stage, a second stage, and decoder circuitry. The first stage includes a first strength tuning circuit having first inverter branches, and a first fine tuning circuit having second inverter branches. The first strength tuning circuit and the first fine tuning circuit are coupled in parallel. The second stage includes a second strength tuning circuit having third inverter branches, and a second fine tuning circuit having fourth inverter branches. The second strength tuning circuit and the second fine tuning circuit are coupled in parallel. Further, the second stage is electrically coupled to the first stage. The decoder circuitry is electrically coupled to the first stage and the second stage. The decoder circuitry controls the first strength tuning circuit independently from the first fine tuning circuit to adjust the duty cycle of an input signal received by the duty cycle adjustment circuitry.

Duty cycle adjustment circuit with independent range and step size control

A byte lane of an integrated circuit including two data strobe loopback paths that allow external test signals to flow in and out of the integrated circuit through data strobe pins in two opposite directions. The integrated circuit includes a Feed Forward Equalization (FFE) path configured to send FFE signals output from the FFE logic via a transmitter set to a first data strobe interface during a normal operation. In a loopback test mode operation, a test signal can be supplied from a second data strobe interface and output to the first data strobe interface by reusing the FFE path. The second loopback path conversely allows a test signal to be routed from the first data strobe interface to the second.

External DQS bi-directional loopback with use of feed forward equalization path

A controller includes first and second functional units, first and second clock-signal sources that provide corresponding first and second clock signals that drive the first and second functional units respectively. The second clock-signal generates its second clock-signal based on the first clock-signal. The clock-retardation unit dynamically causes the second clock-signal to have a target time-domain offset relative to the first clock-signal.

Controlled dynamic de-alignment of clocks

An apparatus for data processing includes first and second functional units driven by corresponding first and second clock-signal sources, and a clock-retardation unit. The clock-retardation unit is configured to cause the second clock-signal to sustain a temporal offset that causes an offset between the first and second clock-signals to step toward a target time-domain offset between the first and second clock-signals.

Controlled multi-step de-alignment of clocks

An apparatus for controlling memory includes a memory controller, and an interface to data lines connecting it to memory. Each line carries a signal that corresponds to a bit to be written to memory. The interface includes, for each line, circuitry for transmitting a bit to memory via the line, and a data de-skewer. For each line, the de-skewer receives a first data signal that represents a bit to be written. Each line has an inherent skew. The de-skewer generates a second data signal by applying a skew to the first. A selected extent of skew increases a likelihood of sampling the second data signal during a data-valid window thereof. The same de-skewer receives and skews a first data bit read from the memory.

Managing skew in data signals

A method for controlling a memory includes causing a data de-skewer to operate in a writing mode, at the data de-skewer, receiving a first signal, and skewing the first data signal by a first compensation skew, causing the data de-skewer to operate in a reading mode, at the data de-skewer, receiving a second signal, and skewing the second signal by a second compensation skew, wherein the first signal is representative of a bit from a byte that is to be written to the memory, and wherein the second signal is representative of a bit from a byte that has been read from the memory.

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Westborough, MA, United States of America

David Da-Wei Lin