Broadcom Corporation

Clariphy Communications, Inc.

Mahyar Kargar

Afshin Momtaz

Namik Kocaman

Siavash Fallahi

Mehdi Khanpour

Ali Nazemi

Carl Grace

Georgios Asmanis

German Cesar Augusto Luna

Sumant Ramprasad

Embodiments for reference-less voltage controlled oscillator (VCO) calibration are provided. Embodiments include a VCO calibration module which uses one or more signals from a frequency detector to automatically select a proper VCO band and bring the VCO clock frequency close enough to the data rate. The VCO calibration module uses a calibration code to calibrate the VCO. In embodiments, the calibration code is determined using a frequency search scheme, which includes a discovery phase to determine the proper VCO band, and a binary search phase and a monitoring phase to select the calibration code that brings the VCO clock frequency closest to the data rate.

Reference-less voltage controlled oscillator (VCO) calibration

Embodiments provide a reference-less frequency detector that overcomes the 'dead zone' problem of conventional circuits. In particular, the frequency detector is able to accurately resolve the polarity of the frequency difference between the VCO clock signal and the data signal, irrespective of the magnitude of the frequency difference and the presence of VCO clock jitter and/or ISI on the data signal.

Reference-less frequency detector

A lookahead pipelined ADC architecture uses open-loop residue amplifiers with calibration. This approach is able to achieve a high-speed, high-accuracy ADC with reduced power consumption. In one aspect, an ADC pipeline unit includes a plurality of lookahead pipeline stages (i.e., an ADC lookahead pipeline) coupled to a calibration unit. The ADC lookahead pipeline uses open-loop residue amplifiers. The calibration unit compensates for non-linearity in the open-loop amplifiers.

Analog-to-digital converter

Growing community of inventors

Irvine, CA, United States of America

Mahyar Kargar