Nvidia Corporation

Samsung Display Co., Ltd.

Sanquan Song

John Wood Poulton

Nikola Nedovic

Walker Joseph Turner

Amir Amirkhany

John M Wilson

Stephen G Tell

Carl Thomas Gray

Sudhir Shrikantha Kudva

Xi Chen

Wei Xiong

Olakanmi Oluwole

Yoshinori Nishi

The disclosure provides a signaling link that overcomes or at least reduces the limitations of RC-dominated signaling wires, improving both the bandwidth and the power consumption of signaling circuits. Both an AC and a DC signaling link are disclosed. In one example, a signaling link is provided that includes: (1) a transmitter including a passive equalizer, (2) an over-terminated receiver, and (3) a lossy channel having a first end connected to the passive equalizer and a second end connected to the receiver, wherein the lossy channel has a channel characteristic impedance that is lower than a terminating impedance of the passive equalizer and a termination impedance of the receiver.

Signaling over RC-dominated transmission lines

A glitch detection device includes an oscillator to generate multiple local clocks of multiple different phases and a sampling circuit to oversample, using the multiple local clocks, a system clock to generate multiple samples of the system clock. The device further includes a glitch detector to monitor a variation in pulse width of the system clock based on counting the multiple samples and to report a glitch in response to detecting a variation in the pulse width that exceeds a threshold value.

Frequency-locked and phase-locked loop-based clock glitch detection for security

Stacked voltage domain level shifting circuits for shifting signals low-to-high or high-to-low include a storage cell powered by a mid-range supply rail of the stacked voltage domain level shifting circuit, and control drivers powered by moving supply voltages generated by the storage cell, wherein the control drivers coupled to drive gates of common-source configured devices coupled to storage nodes of the storage cell.

Level-conversion circuits for signaling across voltage domains

A level-shifting circuits utilizing storage cells for shifting signals low-to-high or high-to-low include control drivers with moving supply voltages. The moving supply voltages may power positive or negative supply terminals of the control drivers. The control drivers drive gates of common-source configured devices coupled to storage nodes of the storage cell.

A glitch detection device includes an oscillator to generate multiple local clocks of multiple different phases and a sampling circuit to oversample, using the multiple local clocks, a system clock to generate multiple samples of the system clock. The device further includes digital logic that in turn includes a glitch detector to monitor a variation in pulse width of the system clock based on counting the multiple samples and to report a glitch in response to detecting a variation in the pulse width that exceeds a threshold value. The digital logic further includes a loop filter coupled between the glitch detector and the oscillator. The loop filter variably adjusts the oscillator based on a frequency of each of the multiple samples to control an output frequency of each of the multiple different phases of the oscillator.

A transceiver circuit includes a receiver front end utilizing a ring oscillator, and a transmitter front end utilizing a pass-gate circuit in a first feedback path across a last-stage driver circuit. The transceiver circuit provides low impedance at low frequency and high impedance at high frequency, and desirable peaking behavior.

CMOS signaling front end for extra short reach links

Voltage level conversion circuits include PMOS pull-down devices or NMOS pull-up devices, and inverters with outputs that determine gate voltages of these devices. The inverters are powered by moving supply voltages, for example complementary supply voltages generated from a pair of cross-coupled inverters. The cross-coupled inverters may implement a data storage latch with the moving supply voltages generated from the internal data storage nodes of the latch.

Level-conversion circuits utilizing level-dependent inverter supply voltages

This disclosure relates to current flattening circuits for an electrical load. The current flattening circuits incorporate randomize various parameters to add noise onto the supply current. This added noise may act to reduce the signal to noise ratio in the supply current, increasing the difficulty of identifying a computational artifact signal from power rail noise.

Techniques to improve current regulator capability to protect the secured circuit from power side channel attack

The disclosure provides an improved transimpedance amplifier (TIA) that can operate at a higher bandwidth and lower noise compared to conventional TIAs. The TIA employs a data path with both feedback impedance and feedback capacitance for improved performance. The feedback impedance includes at least two resistors in series and at least one shunt capacitor, coupled between the at least two resistors, that helps to extend the circuit bandwidth and improve SNR at the same time. The capacitance value of the shunt capacitor can be selected based on both the bandwidth and noise. In one example, the TIA includes: (1) a biasing path, and (2) a data path, coupled to the biasing path, including multiple inverter stages and at least one feedback capacitance coupled across an even number of the multiple inverter stages. An optical receiver and a circuit having the TIA are also disclosed.

Transimpedance amplifier for converting electrical currents to voltages

A linear regulator for applications with low area constraint resulting in limited load decoupling capacitance that introduces a compensating zero in the regulator loop to counteract the loss of phase margin and further introduces a feed-forward noise cancellation path operating over a wide frequency range covering a first package resonance frequency. The feed-forward path has low power consumption and improves the power-supply rejection ratio.

Low area voltage regulator with feedforward noise cancellation of package resonance

A circuit includes a first ring oscillator with a plurality of stages, each coupled via a voltage follower cross-coupling to a plurality of stages of a second ring oscillator. Further ring oscillators may be coupled to the first ring oscillator and the second ring oscillator. Additionally, the voltage follower cross-coupling for each of the stages may include one or more first voltage follower having a first strength, and one or more second voltage follower having a second strength different than the first strength.

Voltage-follower based cross-coupling oscillators with embedded phase-interpolation function

A signal transceiver includes a signal transmitter driving a first differential link between a supply voltage of the signal transmitter and a fraction of the supply voltage, and driving a second differential link between the faction of the supply voltage and a reference ground. The signal transceiver also includes a signal receiver in which the first differential link is coupled to a gate node of an NMOS transistor and to a source node of a PMOS transistor; and the second differential link is coupled to a source node of the NMOS transistor and to a gate node of the PMOS transistor.

Dual-rail transceiver with improved signal-to-noise ratio for differential high-speed links

Injection locked oscillation circuits are applied along clock distribution circuit paths to increase clock signal bandwidth, reduce duty cycle error, reduce quadrature phase error, reduce clock signal jitter, and reduce clock signal power consumption.

Growing community of inventors

Mountain View, CA, United States of America

Sanquan Song