International Business Machines Corporation

Venkat Harish Nammi

Glen Arthur Wiedemeier

Chad Andrew Marquart

Christopher W Steffen

Erik English

Michael Wayne Harper

Dereje G Yilma

Jeffrey Kwabena Okyere

Vikram B Raj

Nathan Ross Blanchard

Daniel Mark Dreps

Pier Andrea Francese

Yang You

James Crugnale

Aspects of the invention include a phase rotator, that is located at a built-in self-test (BIST) path of a receiver, receiving a clock signal from an on-chip clock. The phase rotator shifts the phases of the clock signal. The phase rotator transmits the shifted clock signal to a binary sequence generator, that is located at the receiver. The binary sequence generator outputs a binary sequence, where the binary sequence generator is driven by the shifted clock signal.

Self-contained built-in self-test circuit with phase-shifting abilities for high-speed receivers

A method includes connecting inputs of a first plurality of interpolation branches to a first clock signal, connecting inputs of a second plurality of interpolation branches to a second clock signal, and connecting inputs of a third plurality of interpolation branches to a third clock signal. The method also includes combining outputs of the first plurality of interpolation branches, the second plurality of interpolation branches, and the third plurality of interpolation branches to produce an output clock signal and adjusting a phase of the output clock signal by connecting an input of an interpolation branch of the third plurality of interpolation branches to the second clock signal.

Phase rotator

Aspects of the invention include a driver arranged at a stand-alone receiver that is configured to receive a binary sequence from a pseudorandom binary sequence (PRBS) generator arranged at the receiver. The driver is configured to adjust the signal characteristics of the binary sequence to simulate channel loss at the receiver. The driver is further configured to output the adjusted binary sequence to a downstream data path of the receiver to enable the receiver to perform a self-test.

Built-in-self-test and characterization of a high speed serial link receiver

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Leander, TX, United States of America

Venkat Harish Nammi