Qualcomm Incorporated

Apple Inc.

Bo Sun

Gurkanwal Singh Sahota

Gary John Ballantyne

Zixiang Yang

Jafar Savoj

Sanjeev K Maheshwari

Arun Jayaraman

Sankaran Aniruddhan

Yi Tang

Brian S Leibowitz

Puay Hoe See

Daniel Keyes Butterfield

Joung Won Park

Vladimir Aparin

Chiewcharn Narathong

Dongwon Seo

Rajagopalan Rangarajan

Brett Christopher Walker

Jifeng Geng

David J Maldonado

Francesco Gatta

Cheng Zhong

Alexander Dorosenco

Zae Yong Choi

Yue Wu

Marco Zanuso

William Ronald Panton

Tsai-Pi Hung

Anthony Segoria

Masoud Ensafdaran

Gary J Ballantyne

Manu Mishra

Sriramgopal Sridhara

Giovanni Marucci

Guang Zhang

Anand Gaurav

Jianwen Ye

Anthony F Segoria

The present disclosure describes a circuit that includes a first inductor circuit, a second inductor circuit, a first capacitor circuit, and a second capacitor circuit. The first inductor circuit includes a first inductor and a first driver circuit. The second inductor circuit includes a second inductor and a second driver circuit. The first inductor circuit operates at a first frequency. The second inductor operates at a second frequency. The first capacitor circuit provides a first signal to the second inductor circuit to adjust a first magnetic coupling generated by the first inductor circuit. The second capacitor circuit provides a second signal to the first inductor circuit to adjust a second magnetic coupling generated by the second inductor circuit.

Feedforward cancellation circuit

A current mirror circuit included in a computer system that includes a mirror stage circuit and a feedback circuit is disclosed. The mirror stage circuit generates a mirror current in an output node using a reference current. The feedback circuit adjusts the value of the mirror current based on a voltage level of the output node to increase the output impedance of the current mirror circuit.

High output impedance current mirror circuit

A receiver with feed-forward equalization is disclosed. A receiver includes a delay circuit configured to receive a first signal that encodes a serial data stream having a plurality of data symbols. The delay circuit includes at least one T-coil circuit and is configured to generate a plurality of delayed signals using the first signal. The receiver further includes a front-end circuit configured to generate an equalized signal using the at first signal and one or more delayed signals of the plurality of delayed signals. A sample circuit is configured to sample the equalized signal to generate a plurality of samples. A recovery circuit configured to generate a plurality of recovered data symbols using the plurality of samples.

Receiver with feed forward equalization

A low-power clock generation circuit has a phase generator that receives an input clock signal and uses the input clock signal to generate multiple intermediate clock signals with different phase shifts, a phase rotator circuit that outputs phase-adjusted clock signals, a frequency doubler circuit that receives a plurality of the phase-adjusted clock signals and outputs two frequency-doubled clock signals having a 180&#xb0; phase difference, and a quadrature clock generation circuit that receives the two frequency-doubled clock signals and provides four output signals that include in-phase and quadrature versions of the two frequency-doubled clock signals.

Low-power high-speed CMOS clock generation circuit

Embodiments relate to a circuit implementation for controlling a delay of a clock signal. The clock delay control circuit includes a sensing circuit and a phase interpolator controlled by the sensing circuit. The sensing circuit generates a first control signal that increases when a level of a supply voltage increases, and decreases when the level of the supply voltage decreases. Moreover, the sensing circuit generates a second control signal that decreases when the level of the supply voltage increases, and increases when the level of the supply voltage decreases. The phase interpolator includes multiple paths, each having a different propagation delay. The coupling between each path and the output node of the phase interpolator is controlled by the control signals generated by the sensing circuit.

On-chip supply ripple tolerant clock distribution

In certain aspects, an amplifier includes a first transistor including a gate, a drain, and a source, wherein the gate of the first transistor is coupled to a first input of the amplifier. The amplifier also includes a second transistor including a gate, a drain, and a source, wherein the gate of the second transistor is coupled to a second input of the amplifier. The amplifier further includes a first signal path coupled between the first input of the amplifier and the source of the second transistor, a second signal path coupled between the second input of the amplifier and the source of the first transistor, a first load coupled to the drain of the first transistor, and a second load coupled to the drain of the second transistor.

Amplifier with gain boosting

Aspects generally relate to reducing delay, or phase jitter, in high speed signals transmission. Variations in power supply to ground potential changes the amount of delay introduced by transmit circuitry into the signal being transmitted, resulting in jitter, or phase noise, in the transmitted signal. To reduce phase jitter, or phase noise, aspects disclosed include a variable impedance circuit coupled to the signal distribution network, the impedance level of the variable impedance circuit is adjusted in response to variation in the supply to ground potential, such that the delay introduced by the impedance compensates for changes in the delay due to variations in supply to ground potential, resulting in substantially constant delay.

Supply compensated delay cell

A delay-locked loop (DLL) is provided that includes both a first delay line and a second delay line. The delay-locked loop functions to synchronize a DLL output clock signal relative to a received clock signal using the first delay line while a phase difference between the received clock signal and a received data signal corresponds to a delay within an operating range for the first delay line. As the phase difference increases to force the first delay line out of its operating range, the delay-locked loop transitions to using the second delay line to synchronize the DLL output clock signal relative to the received clock signal.

Delay-locked loop with large tuning range

In certain aspects, a serial-to-parallel converter includes multiple cascaded stages configured to convert a serial data stream into multiple parallel data signals, wherein each of the stages includes one or more demultiplexers. The serial-to-parallel converter also includes demultiplexer control circuits, wherein each of the demultiplexer control circuits is coupled to the one or more demultiplexers of a respective one of the stages, and a pattern detector coupled to the demultiplexer control circuits.

Programmable bit alignment at serial-to-parallel stage of SerDes

Multi-phase clock generation employing phase error detection between multiple delay circuit outputs in a controlled delay line to provide error correction is disclosed. A multi-phase clock generator is provided that includes a controlled delay line and a phase error detector circuit. Tap nodes are provided from outputs of one or more delay circuits in the controlled delay line. To detect and correct for phase errors in the controlled delay line, a phase detection circuit is provided that includes at least two phase detectors each configured to measure a phase offset error between tap nodes from the delay circuit(s) in the controlled delay line. These phase errors are then combined to create an error correction signal, which is used to control the delay of the delay circuit(s) in the controlled delay line to lock the phase of the output of the final delay circuit to an input reference clock signal.

Multi-phase clock generation employing phase error detection in a controlled delay line

One feature pertains to an apparatus that includes a first stage track and hold circuit that subsamples a receive equalizer output of a receive equalizer, and a second stage track and hold circuit that generates a first signal representative of an average voltage value of a logical value at the receive equalizer output when a high frequency bit pattern is detected, and a second signal representative of an average voltage value of the logical value at the receive equalizer output when a steady state bit pattern is detected. The apparatus further includes a comparator circuit that generates a comparator output signal that indicates which of the first signal and the second signal has a greater magnitude, and a processing circuit that generates equalizer tuning signals based on the comparator output signal to adjust parameters of an equalizer that affects the receive equalizer output.

Serial link adaptive equalization using track and hold circuits

A fast frequency hopping implementation in a phase lock loop (PLL) circuit achieves a PLL lock to a new frequency in a very short period of time. In one instant, frequency allocation at a transceiver is changed. In response, a local oscillator frequency hops to a new center frequency based on the changed frequency allocation. The hopping to the new center frequency is based on two-point modulation of a phase locked loop.

Fast frequency hopping phase locked loop

An ionic current sensor array includes a master bias generator and a plurality of sensing cells. The master bias generator is configured to generate a bias voltage. Each sensing cell includes an ionic current sensor, an integrating capacitor, a sense transistor coupled between the integrating capacitor and the ionic current sensor, and an amplifier coupled to provide a reference voltage to bias the ionic current sensor. The amplifier includes a first transistor and a second transistor. The first transistor is coupled to receive the bias voltage, and the second transistor is coupled to the first transistor to provide the reference voltage to the ionic current sensor. The second transistor is also coupled between a source of the sense transistor and the gate of the sense transistor.

Biasing of an ionic current sensor

One feature pertains to a digitally controlled oscillator (DCO) that comprises a variable capacitor and noise reduction circuitry. The variable capacitor has a variable capacitance value that controls an output frequency of the DCO. The variable capacitance value is based on a first bank capacitance value provided by a first capacitor bank, a second bank capacitance value provided by a second capacitor bank, and an auxiliary bank capacitance value provided by an auxiliary capacitor bank. The noise reduction circuitry is adapted to adjust the variable capacitance value by adjusting the auxiliary bank capacitance value while maintaining at least one of the first bank capacitance value and/or the second bank capacitance value substantially unchanged. Prior to adjusting the variable capacitance value, the noise reduction circuitry may determine that a received input DCO control word transitions across a capacitor bank sensitive boundary.

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Carlsbad, CA, United States of America

Bo Sun