Xilinx, Inc.

Michael Mass

David Erich Tetzlaff

Michael J Gaboury

Khaldoun Bataineh

A device and a method for processing high data rate serial data includes a VCO initial frequency calibration circuit. The circuit includes a frequency detection block for indicating a difference between a reference clock and a divided VCO clock, a frequency calibration block that produces a digital output signal based upon the difference between the reference clock and the divided VCO clock, and a digital-to-analog converter for producing an analog VCO adjust signal. The frequency detection block produces a plurality of signals based upon the reference clock and the divided VCO clock. A plurality of user selected inputs selects a frequency detection lock range and hysteresis range and a coarse loop open calibration lock and hysteresis range. The frequency calibration block implements a state machine for producing the digital output signal that sets the initial operating frequency then adjusts the frequency of the VCO clock.

Growing community of inventors

Mendota Heights, MN, United States of America

Michael Mass