Qualcomm Incorporated

Integrated Memory Logic, Inc.

Jeongsik Yang

Sang-Oh Lee

Young Gon Kim

Shen Wang

Mazhareddin Taghivand

Thinh Cat Nguyen

Chiayao S Tung

Shuen-Chin Chang

Yong E Park

Ara Bicakci

Anup Savla

Yongwang Ding

Cheng-Han Wang

Roger Brockenbrough

Justin Phelps Black

Emilia Vailun Lei

Jianlei Shi

Cindy Yuklin Ng

Yido Koo

Yue Lu

Yi Zeng

Yashar Rajavi

Hong Sun Kim

Jin-Su Ko

Chan Hong Park

Jawji Chen

Zuow-Zun Chen

Ngar Loong Alan Chan

David Ta-hsiang Lin

Conor Donovan

Jin Wook Kim

Burcin Baytekin

Kiyong Choi

Keplin Victor Johansen

Wei-Han Cho

Xiaoyu Wang

Ji-Hoon Park

Roger Thomas Brockenbrough

Justin Black

Certain aspects relate to a semiconductor die. The semiconductor die includes a voltage-controlled oscillator (VCO), wherein the VCO includes a resonant capacitor, and a resonant inductor coupled in parallel with the resonant capacitor. The resonant inductor includes a first elongated portion and a second elongated portion that are parallel with each other. The semiconductor die also includes a voltage supply line configured to route a supply voltage to the VCO, wherein the voltage supply line includes a first portion that runs parallel with the first and second elongated portions of the resonant inductor and is located between the first and second elongated portions of the resonant inductor.

Layout for voltage-controlled oscillator (VCO)

An apparatus and a method are disclosed for synchronizing clock signals distributed within a wireless device. In some embodiments, a local oscillator (LO) clock signal is buffered and distributed to two or more transceivers within the wireless device. Each transceiver may include a configurable clock divider to divide the distributed LO clock signal and generate an output clock signal. A phase detector compares output clock signals from each of the configurable clock dividers and generates an output signal in accordance with a determined phase difference. The phase detector output signal may cause at least one of the configurable clock dividers to modify its respective output clock signal, and thereby synchronize output clock signals between different configurable clock dividers. In some embodiments, a clock signal from a configurable clock divider may be modified (shifted) by approximately 90 or 180 degrees.

Clock synchronization

An open-loop feed-forward cross-correlator noise cancellation device includes a synthesizer to generate a synthesized output clock signal based on a reference clock signal. The open-loop feed-forward cross-correlator noise cancellation device also includes a cross-correlator device coupled to the synthesizer to receive the reference clock signal and the synthesized output clock signal and to cross-correlate the reference clock signal and the synthesized output clock signal to generate a cross-correlated output signal. The open-loop feed-forward cross-correlator noise cancellation device further includes a signal control delay line coupled to the cross-correlator device to generate an anti-phase noise signal based on the cross-correlated output signal to counter uncorrelated phase noise from additional circuitry of the synthesizer.

Frequency/phase synthesizer noise cancellation

Certain aspects of the present disclosure generally relate to voltage-controlled oscillators (VCOs) using a lowered or an adjustable negative transconductance (&#x2212;g) compared to conventional VCOs. This &#x2212;gdegeneration technique suppresses the noise injected into an inductor-capacitor (LC) tank of the VCO, thereby providing lower signal-to-noise ratio (SNR) for a given VCO voltage swing, lower power consumption, and decreased phase noise. One example VCO generally includes a resonant tank circuit, an active negative transconductance circuit connected with the resonant tank circuit, and a bias current circuit for sourcing or sinking a bias current through the resonant tank circuit and the active negative transconductance circuit to generate an oscillating signal. The active negative transconductance circuit includes cross-coupled transistors and an impedance connected between the cross-coupled transistors and a reference voltage.

[object Object]

The present disclosure describes current steering phase control for current-mode logic (CML) circuits. In some aspects, a circuit for frequency division comprises a current sink connected to a ground rail. The circuit also includes first and second current-carrying branches of frequency-dividing circuitry operably connected to respective load resistors, which are connected to a power rail. A first switch element of the circuit is connected between the current sink and the first current-carrying branch and a second switch element of the circuit is connected between the current sink and the second current-carrying branch. The first and second switch elements may steer current sank by the current sink between the first and second current-carrying branches effective to alter a phase of a signal provided by the frequency division circuit.

Current steering phase control for CML circuits

Low noise and low power voltage-controlled oscillator (VCO) using transconductance (gm) degeneration

The disclosure is directed to compensating for frequency drift in a voltage-controlled oscillator (VCO). Example methods and systems are described which may detect a signal edge associated with a transceiver, and determine whether one or more lock quality signals indicate that the VCO frequency is outside of an specified range, indicating an unacceptable amount of frequency drift. A frequency tuning setting of the VCO may be adjusted based on the one or more lock quality signals, and a determination may be made whether or not the one or more lock quality signals indicate that the VCO frequency has returned to the specified range. The adjustment of the frequency tuning setting of the VCO may be repeated until the VCO frequency returns to the specified range.

Closed loop bank selection for temperature compensation in wireless systems

Methods and apparatus for synchronizing dividers in different LO paths using pulse swallowing. One example apparatus generally includes a first path having a first frequency divider configured to generate a first divided signal from a first periodic signal; a second path having a second frequency divider configured to generate a second divided signal from a second periodic signal; a phase detector configured to compare phases of a first sensing signal based on the first divided signal and a second sensing signal based on the second divided signal and to generate a first trigger signal if the first and second sensing signals are out-of-phase; and a first pulse suppressor configured to suppress a pulse of the first periodic signal for at least one cycle in response to the first trigger signal to adjust a phase of the first divided signal.

Methods and apparatus for synchronizing frequency dividers using a pulse swallowing technique

Reducing coupling and mismatch in multi-core VCOs, including: arranging a plurality of inductors in a plurality of VCO cores in a parallel differential inductor configuration with shared leads to form a single node, wherein the plurality of inductors includes at least a first inductor and a second inductor; connecting power/ground traces to the first inductor from a first side only; and connecting the power/ground traces to the second inductor from another side different from the first side only to avoid making a current loop.

Reducing mismatch caused by power/ground routing in multi-core VCO structure

Certain aspects of the present disclosure provide methods and apparatus for temperature-dependent adjustment of a resonant circuit, such as that found in a voltage-controlled oscillator (VCO). Such adjustment may be performed in an effort to compensate for the frequency drift of the resonant circuit due to temperature changes. One example adjustment circuit for temperature-dependent adjustment of a resonant circuit generally includes at least one varactor and two sets of semiconductor devices configured to apply, across the at least one varactor, a differential adjustment voltage based on an ambient temperature of the semiconductor devices to adjust a capacitance of the at least one varactor, wherein each device in the sets of semiconductor devices has a temperature-dependent junction and wherein the two sets of semiconductor devices are configured such that voltage changes of the temperature-dependent junctions in the two sets of semiconductor devices are added in the differential adjustment voltage.

Resonant circuit temperature compensation

A transformer is described. The transformer includes a primary coil and a first secondary coil. A first coupling occurs between the first secondary coil and the primary coil. The transformer also includes a second secondary coil. A second coupling occurs between the second secondary coil and the primary coil. The first secondary coil is separated from the second secondary coil to prevent coupling between the first secondary coil and the second secondary coil. A first width of the first secondary coil is configured independently of a second width of the second secondary coil.

Transformer feedback voltage controlled oscillator (VCO)

Certain aspects of the present invention provide methods and apparatus for detecting phase shift between signals, such as local oscillating signals in adjacent transceiver paths. One example circuit for phase detection generally includes a mixer configured to mix a first input signal having a first frequency with a second input signal having a second frequency to produce an output signal having frequency components at the sum of and the difference between the first and second frequencies; a filter connected with the mixer and configured to remove one of the frequency components at the sum of the first and second frequencies, thereby leaving a DC component; and an analog-to-digital converter (ADC) (e.g., a comparator) connected with the filter and configured to determine whether the first input signal is in-phase or out-of-phase with the second input signal based on a comparison between the DC component and a reference signal.

Phase detecting circuit for interchain local oscillator (LO) divider phase alignment

Aspects of a wireless apparatus and a method for handling a modulated signal include a frequency generator that produces a clock signal, a first synchronization circuit that generates a first sync enable signal based on an even edge of the clock signal, a second synchronization circuit that generates a second sync enable signal based on an even edge of the clock signal, a first divider having a first initial operating condition that generates a first IQ path based on the first sync enable signal, and a second divider having a second initial operating condition that generates a second IQ path based on the second sync enable signal, wherein the first and second operating conditions are not equal when initially powered.

Multi IQ-path synchronization

A method, an apparatus, and a computer program product are provided. The apparatus tunes a frequency provided by a VCO. The apparatus determines a relative capacitance change associated with a first frequency and a desired frequency from a look-up table. The apparatus adjusts a capacitor circuit in the VCO based on the determined relative capacitance change determined from the look-up table in order to tune from the first frequency to the desired frequency. The apparatus determines that the frequency provided by the VCO is a second frequency different than the desired frequency after adjusting the capacitor circuit. The apparatus performs an iterative search to further adjust the capacitor circuit when a difference between the second frequency and the desired frequency is greater than a threshold.

Voltage controlled oscillator band-select fast searching using predictive searching

System for I-Q phase mismatch detection and correction. An apparatus to correct a phase mismatch between I and Q signals includes a correction circuit configured to continuously compare a reference signal and a phase error signal associated with the I and Q signals to generate an I bias signal and a Q bias signal, a first CMOS buffer configured to receive the I signal and the I bias signal and output a phase adjusted I signal based on the I bias signal, and a second CMOS buffer configured to receive the Q signal and the Q bias signal and output a phase adjusted Q signal based on the Q bias signal.

System for I-Q phase mismatch detection and correction

Growing community of inventors

San Jose, CA, United States of America

Jeongsik Yang