Cadence Design Systems, Inc.

Sachin Ramesh Gugwad

Hari Anand Ravi

Thomas Evan Wilson

Vinod Kumar

Jitendra Kumar Yadav

Scott David Huss

Hajee Mohammed Shuaeb Fazeel

Aaron Willey

H Md Shuaeb Fazeel

Balbeer Rathor

Tara Vishin

Jaya Madhaba Panda

A high-speed clocking circuit may include a single path digitally controlled coarse delay line including multiple stages. Each of the multiple stages may include a plurality of inverters and a logic gate electrically connected in series that are configured to enable a forward path of the single path digitally controlled coarse delay line prior to disabling a return path of the single path digitally controlled coarse delay line to minimize glitching.

Efficient clocking structures for high-speed systems using hybrid digital delay lanes

Various embodiments described herein provide for a read data strobe (RDQS) path having variation compensation (e.g., voltage and temperature compensation), delay lines, or both, where the RDQS path can be included by a physical (PHY) interface for a memory device, such as a Double Data Rate (DDR) Dynamic Random-Access Memory (DRAM) memory device.

Read data strobe path having variation compensation and delay lines

The present disclosure relates to a system and method for duty cycle correction is provided. The method may include receiving a signal at a duty cycle adjuster and performing serializer clock duty cycle correction at the duty cycle adjuster. The method may further include performing true clock duty cycle correction at a transmitter duty cycle adjuster and performing complementary duty cycle distortion correction at the transmitter duty cycle adjuster.

System and method for write clock double data rate duty cycle correction

Various embodiments provide for identifying and training a floating tap for decision feedback equalization. For some embodiments, the identification and training of the floating tap described herein can be part of a circuit for receiver block of a system, such as a memory system.

Identifying and training floating tap for decision feedback equalization

Various aspects of the subject technology relate to systems, methods, and machine-readable media for DDR reference voltage training. The method includes receiving a data stream, the data stream including pulses generated from a reference voltage in relation to a voltage input logic low and a voltage input logic high of an input stream. The method also includes receiving a clock signal, the clock signal including an in-phase signal and a quadrature-phase signal, the in-phase signal orthogonal to the quadrature-phase signal. The method also includes utilizing the in-phase signal and the quadrature-phase signal of the clock signal in relation to the data stream to obtain a stream of in-phase samples and a stream of quadrature-phase samples. The method also includes adjusting the reference voltage based on a relationship of the stream of in-phase samples to the stream of quadrature-phase samples.

Reference voltage training scheme

Disclosed is an improved approach for a training approach to implement DFE for an electronic circuit. The inventive concept is particularity suitable to address, for example, circuits that implement high speed parallel data transmission protocols, such as GDDR6, that are used for graphics applications. The training scheme uses minimal hardware when compared to existing schemes by reusing calibration receiver in auto zeroing receiver as error receiver. Further it works for closed eyes by running the algorithm multiple times with gradual increase in complexity of training pattern, where DFE coefficients from previous iteration is used for the current iteration, thereby gradually opening the eye.

Hardware efficient decision feedback equalization training

The embodiments described herein provide for a method and system for training an optimal decision feedback equalization (DFE) coefficient for use in GDDR and DDR applications. The method includes determining a first expected bit pattern using a reference voltage. The method further includes determining a transition voltage value of the first expected bit pattern. The method further includes receiving a second expected bit pattern having a same first bit as the first expected bit pattern. The method further includes determining a transition voltage value of the second expected bit pattern using the reference voltage. The method further includes calculating an optimal reference voltage value by averaging the transition voltage values of the first expected bit pattern and the second-expected bit pattern and storing the optimal reference voltage value in a register corresponding to a logic value of the same first bit.

Decision feedback equalization training scheme for GDDR applications

The present disclosure relates to an apparatus and method for continuous time linear equalization. Embodiments include determining, using a decision feedback equalization ('DFE') training block, a voltage value for one or more resistor values. Embodiments may further include determining, using the DFE training block, a voltage value for one or more capacitor values and identifying a voltage difference between the voltage value for one or more resistor values and the voltage value for one or more capacitor values. Embodiments may further include iteratively performing the determining of the voltage value and identifying of the voltage difference for each of the plurality of capacitor values until the voltage difference is at one or more minimum values to generate one or more optimal resistor and capacitor coefficients for a continuous time linear equalization filter.

Continuous time linear equalization system and method

Embodiments relate to systems, methods, and computer-readable media to enable design and creation of crosstalk cancellation circuitry for a receiver (e.g. an AC coupled DDR5 receiver). One embodiment is a receiver apparatus with crosstalk victim and aggressors lines. The cancellation circuitry involves an amplifier and buffering circuitry to provide inductive and capacitive crosstalk cancellation voltages. Some embodiments can additionally involve circuitry for autozeroing modes for AC coupled receiver lines.

Crosstalk cancellation in a receiver

Embodiments relate to circuits, electronic design automation (EDA) circuit layouts, systems, methods, and computer readable media to enable logic devices operating on a core supply voltage to drive memory devices operating on a different supply voltage using low power and high data rates while avoiding voltage over-stress of thin-oxide transistors. In an embodiment, channels of a thin-oxide PMOS transistor, a thick-oxide PMOS transistor, a thick-oxide NMOS transistor, and a thin-oxide NMOS transistor are coupled in order from a memory device voltage supply rail to a low voltage supply rail. Gates of the thin-oxide PMOS transistor and the thick-oxide NMOS transistor are coupled with an output of a flying capacitor circuit that level-shifts an input signal by a difference between the memory device supply and core supply voltages, while gates of the thick-oxide PMOS transistor and the thin-oxide NMOS transistor receive the input signal via a buffer.

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Bengaluru, India

Sachin Ramesh Gugwad