Xilinx, Inc.

Jaewook Shin

Parag Upadhyaya

Hiva Hedayati

Didem Z Turker Melek

Shaojun Ma

A quadrature clock generator is disclosed. The quadrature clock generator may include a first injection-locked oscillator, a phase interpolator, and a second injection-locked oscillator. The first injection-locked oscillator may generate a first plurality clock signals from a first reference clock signal. The phase interpolator may generate a second reference clock signal from the first plurality of clock signals, and the second injection-locked oscillator may generate a second plurality of clock signals from the second reference clock signal. A first quadrature clock signal may be selected from the first plurality of clock signals and a second quadrature clock signal may be selected from the second plurality of reference clock signals.

Low noise quadrature signal generation

Electrical circuits and associated methods relate to duty cycle correction having a voltage controlled delay line VCDL controlled by an analog voltage and a digital command signal to generate a VCDLsignal. In an illustrative example, the analog voltage may be generated by an analog circuit, the analog circuit may include a reference voltage, a low-pass filter, an amplifier and a loop filter. In an illustrative example, the analog circuit may be controlled by an analog command signal. The analog command signal may be programmable applied on the analog circuit to produce the analog voltage. The digital command signal may be programmable to select desired delay band in the VCDL. The analog voltage and the digital command signal may be applied to the VCDL together to obtain a desired duty cycle.

Electrical circuits and methods to correct duty cycle error

A circuit for compensating for mismatch in a plurality of channels of a time-interleaved analog-to-digital converter is described. The circuit comprises an analog-to-digital converter circuit of a first channel of the plurality of channels configured to receive an analog input signal and to generate a digital value associated with the analog input signal; an arithmetic circuit configured to receive the digital value generated at the output of the analog-to-digital converter; a memory element configured to receive an output of the arithmetic circuit; and an accumulator circuit coupled to the memory element, wherein the accumulator generates an average value that is provided to the arithmetic circuit to modify the digital value generated at the output of the analog-to-digital converter while receiving the analog input signal.

Circuit for and method of compensating for mismatch in a time-interleaved analog-to-digital converter

A circuit for implementing a time-interleaved analog-to-digital converter is described. The circuit comprises a sampling clock generator configured to receive a reference clock signal having a first frequency. The sampling clock generator has a first stage sampling clock generator configured to generate a first plurality of clock signals based upon the reference clock signal and having a second frequency, and a second stage sampling clock generator configured to generate, for each clock signal of the first plurality of clock signals, a second plurality of clock signals having a third frequency; a first stage having a plurality of switches configured to receive an analog input signal, wherein each switch of the plurality of switches is controlled by a corresponding clock signal of the first plurality of clock signals; and a second stage having a plurality of analog-to-digital converter banks, each analog-to-digital converter bank having a plurality of analog-to-digital converters and configured to receive the analog input signal by way of a corresponding switch of the plurality of switches.

Growing community of inventors

San Jose, CA, United States of America

Jaewook Shin