Marvell Asia Pte., Ltd.

Broadcom Corporation

Avago Technologies General IP (singapore) Pte. Ltd.

Fazil Ahmad

Pin-En Su

Quanli Lu

Liang Fan

Cindra Abidin

Espen Olsen

Greg Alyn Unruh

Pera Florin

William Huff

Morteza Azarmnia

Marco Garampazzi

Tomas Dusatko

A time-interleaved current-based digital-to-analog converter (current DAC) cell includes first input circuitry configured to receive a digital input signal, a first biasing voltage, a first clock, and a second clock. The first clock and the second clock having a phase offset from one another and having a common period. The current DAC also includes a first gate configured to, responsive to an 'ON' state of the first clock, pass the digital input signal to a second gate, the second gate being configured to, responsive to an ‘OFF’ state of the second clock, output a first DAC cell activation signal. The current DAC further includes first output circuitry configured to, responsive to the first DAC cell activation signal, output a first analog current signal based on (i) the digital input signal and (ii) the first biasing voltage.

Time-interleaved current-based digital-to-analog converter (current DAC)

A method for dynamically calibrating a time-interleaved digital-to-analog converter (DAC) includes receiving a digital input signal, generating, from the digital input signal, an output analog signal using DAC circuitry, generating, from the digital input signal, a model analog signal using DAC modeling circuitry, adjusting a digital model based on the model analog signal and the digital input signal, determining at least one of an offset error and a gain error based on comparing the output analog signal to the model analog signal, and generating an error correction signal based on the at least one of an offset error and a gain error.

Method for adaptive calibration of a digital-to-analog converter (DAC)

An integrated circuit transceiver device includes a plurality of functional circuits, and clock circuitry for distributing synchronous, in-phase, phase-locked clock signals to all transceiver circuits. The clock circuitry includes a frequency-controllable distributed oscillator including at least one coupled pair of transmission line oscillators having a respective oscillator core, and at least one respective transmission line segment. At least one impedance element couples the at least one respective transmission line segment of a first transmission line oscillator to the at least one respective transmission line segment of a second transmission line oscillator. Impedance of the impedance element is different from impedance of each respective transmission line segment to cause reflection at the at least one impedance element. At least one tap corresponding to each respective one of the transmission line oscillators outputs synchronous, in-phase, phase-locked clock signals for the functional circuits at points along the distributed oscillator.

Tunable distributed oscillator

Method and apparatus for fast phase locked loop (PLL) settling with reduced frequency overshoot are provided. During acquisition, a first phase offset signal configured to drive a phase error signal to zero is provided at a first circuit of the PLL. The first circuit may be a time-to-digital converter (TDC) of the PLL. A second phase offset signal configured to offset the first phase offset signal is provided at a second circuit of the PLL. The second circuit of the PLL may be a loop filter at the PLL.

Method and apparatus for fast phase locked loop (PLL) settling with reduced frequency overshoot

The problem with duty-cycle correction circuits used by conventional frequency doublers is that they typically analog solutions, such as variable delay lines with long chains of inverters or buffers, that directly adjust the reference signal used by a phase-locked loop (PLL). These solutions can considerably increase the noise (e.g., thermal noise and supply noise) of the reference signal, as well as the overall power consumption and cost of the PLL. Rather than directly correct the duty-cycle of the reference signal, the present disclosure is directed to an apparatus and method for measuring the period error between adjacent cycles of a frequency doubled reference signal in terms of cycles of the output signal generated by the PLL (or some other higher frequency signal) and adjusting the division factor of the PLL frequency divider to compensate for the measured period error.

Frequency multiplier for a phase-locked loop

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Irvine, CA, United States of America

Fazil Ahmad