Rambus Inc.

Hsuan-Jung Su

Jared L Zerbe

Brian S Leibowitz

John M Wilson

Lei Luo

Jihong Ren

Barry William Daly

John Cronan Eble, Iii

Teva J Stone

Wayne D Dettloff

Robert E Palmer

Andrew M Fuller

An integrated circuit comprises a signal transmitter and a sampling circuit coupled to the signal transmitter, wherein the sampling circuit is to sample output voltage levels of an output of the signal transmitter at different respective times. The integrated circuit further comprises a measurement circuit coupled to the sampling circuit, wherein the measurement circuit is to compare the output voltage levels of the output of the signal transmitter to corresponding reference voltages to identify a first time when a first output voltage level equals a first reference voltage and a second time when a second output voltage level equals a second reference voltage. A time difference between the first time and the second time is used to configure a slew rate adjustment control of the signal transmitter.

Integrated transmitter slew rate calibration

A low-power, high-performance source-synchronous chip interface which provides rapid turn-on and facilitates high signaling rates between a transmitter and a receiver located on different chips is described in various embodiments. Some embodiments of the chip interface include, among others: a segmented 'fast turn-on' bias circuit to reduce power supply ringing during the rapid power-on process; current mode logic clock buffers in a clock path of the chip interface to further reduce the effect of power supply ringing; a multiplying injection-locked oscillator (MILO) clock generator to generate higher frequency clock signals from a reference clock; a digitally controlled delay line which can be inserted in the clock path to mitigate deterministic jitter caused by the MILO clock generator; and circuits for periodically re-evaluating whether it is safe to retime transmit data signals in the reference clock domain directly with the faster clock signals.

Method and apparatus for source-synchronous signaling

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Chapel Hill, NC, United States of America

Hsuan-Jung Su