Patents by Inventor Wendemagegnehu Beyene

Wendemagegnehu Beyene has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20230353177
    Abstract: Decision feedback equalization (DFE) is used to help reduce inter-symbol interference (ISI) from a data signal received via a band-limited (or otherwise non-ideal) channel. A first PAM-4 DFE architecture has low latency from the output of the samplers to the application of the first DFE tap feedback to the input signal. This is accomplished by not decoding the sampler outputs in order to generate the feedback signal for the first DFE tap. Rather, weighted versions of the raw sampler outputs are applied directly to the input signal without further analog or digital processing. Additional PAM-4 DFE architectures use the current symbol in addition to previous symbol(s) to determine the DFE feedback signal. Another architecture transmits PAM-4 signaling using non-uniform pre-emphasis. The non-uniform pre-emphasis allows a speculative DFE receiver to resolve the transmitted PAM-4 signals with fewer comparators/samplers.
    Type: Application
    Filed: May 8, 2023
    Publication date: November 2, 2023
    Inventors: Masum HOSSAIN, Nhat NGUYEN, Yikui Jen DONG, Arash ZARGARAN-YAZD, Wendemagegnehu BEYENE
  • Patent number: 11683057
    Abstract: Decision feedback equalization (DFE) is used to help reduce inter-symbol interference (ISI) from a data signal received via a band-limited (or otherwise non-ideal) channel. A first PAM-4 DFE architecture has low latency from the output of the samplers to the application of the first DFE tap feedback to the input signal. This is accomplished by not decoding the sampler outputs in order to generate the feedback signal for the first DFE tap. Rather, weighted versions of the raw sampler outputs are applied directly to the input signal without further analog or digital processing. Additional PAM-4 DFE architectures use the current symbol in addition to previous symbol(s) to determine the DFE feedback signal. Another architecture transmits PAM-4 signaling using non-uniform pre-emphasis. The non-uniform pre-emphasis allows a speculative DFE receiver to resolve the transmitted PAM-4 signals with fewer comparators/samplers.
    Type: Grant
    Filed: November 16, 2021
    Date of Patent: June 20, 2023
    Assignee: Rambus Inc.
    Inventors: Masum Hossain, Nhat Nguyen, Yikui Jen Dong, Arash Zargaran-Yazd, Wendemagegnehu Beyene
  • Publication number: 20220149876
    Abstract: Decision feedback equalization (DFE) is used to help reduce inter-symbol interference (ISI) from a data signal received via a band-limited (or otherwise non-ideal) channel. A first PAM-4 DFE architecture has low latency from the output of the samplers to the application of the first DFE tap feedback to the input signal. This is accomplished by not decoding the sampler outputs in order to generate the feedback signal for the first DFE tap. Rather, weighted versions of the raw sampler outputs are applied directly to the input signal without further analog or digital processing. Additional PAM-4 DFE architectures use the current symbol in addition to previous symbol(s) to determine the DFE feedback signal. Another architecture transmits PAM-4 signaling using non-uniform pre-emphasis. The non-uniform pre-emphasis allows a speculative DFE receiver to resolve the transmitted PAM-4 signals with fewer comparators/samplers.
    Type: Application
    Filed: November 16, 2021
    Publication date: May 12, 2022
    Inventors: Masum HOSSAIN, Nhat NGUYEN, Yikui Jen DONG, Arash ZARGARAN-YAZD, Wendemagegnehu BEYENE
  • Patent number: 11211960
    Abstract: Decision feedback equalization (DFE) is used to help reduce inter-symbol interference (ISI) from a data signal received via a band-limited (or otherwise non-ideal) channel. A first PAM-4 DFE architecture has low latency from the output of the samplers to the application of the first DFE tap feedback to the input signal. This is accomplished by not decoding the sampler outputs in order to generate the feedback signal for the first DFE tap. Rather, weighted versions of the raw sampler outputs are applied directly to the input signal without further analog or digital processing. Additional PAM-4 DFE architectures use the current symbol in addition to previous symbol(s) to determine the DFE feedback signal. Another architecture transmits PAM-4 signaling using non-uniform pre-emphasis. The non-uniform pre-emphasis allows a speculative DFE receiver to resolve the transmitted PAM-4 signals with fewer comparators/samplers.
    Type: Grant
    Filed: December 8, 2020
    Date of Patent: December 28, 2021
    Assignee: Rambus Inc.
    Inventors: Masum Hossain, Nhat Nguyen, Yikui Jen Dong, Arash Zargaran-Yazd, Wendemagegnehu Beyene
  • Publication number: 20210152205
    Abstract: Decision feedback equalization (DFE) is used to help reduce inter-symbol interference (ISI) from a data signal received via a band-limited (or otherwise non-ideal) channel. A first PAM-4 DFE architecture has low latency from the output of the samplers to the application of the first DFE tap feedback to the input signal. This is accomplished by not decoding the sampler outputs in order to generate the feedback signal for the first DFE tap. Rather, weighted versions of the raw sampler outputs are applied directly to the input signal without further analog or digital processing. Additional PAM-4 DFE architectures use the current symbol in addition to previous symbol(s) to determine the DFE feedback signal. Another architecture transmits PAM-4 signaling using non-uniform pre-emphasis. The non-uniform pre-emphasis allows a speculative DFE receiver to resolve the transmitted PAM-4 signals with fewer comparators/samplers.
    Type: Application
    Filed: December 8, 2020
    Publication date: May 20, 2021
    Inventors: Masum HOSSAIN, Nhat NGUYEN, Yikui Jen DONG, Arash ZARGARAN-YAZD, Wendemagegnehu BEYENE
  • Patent number: 10892791
    Abstract: Decision feedback equalization (DFE) is used to help reduce inter-symbol interference (ISI) from a data signal received via a band-limited (or otherwise non-ideal) channel. A first PAM-4 DFE architecture has low latency from the output of the samplers to the application of the first DFE tap feedback to the input signal. This is accomplished by not decoding the sampler outputs in order to generate the feedback signal for the first DFE tap. Rather, weighted versions of the raw sampler outputs are applied directly to the input signal without further analog or digital processing. Additional PAM-4 DFE architectures use the current symbol in addition to previous symbol(s) to determine the DFE feedback signal. Another architecture transmits PAM-4 signaling using non-uniform pre-emphasis. The non-uniform pre-emphasis allows a speculative DFE receiver to resolve the transmitted PAM-4 signals with fewer comparators/samplers.
    Type: Grant
    Filed: November 12, 2019
    Date of Patent: January 12, 2021
    Assignee: Rambus Inc.
    Inventors: Masum Hossain, Nhat Nguyen, Yikui Jen Dong, Arash Zargaran-Yazd, Wendemagegnehu Beyene
  • Publication number: 20200153468
    Abstract: Decision feedback equalization (DFE) is used to help reduce inter-symbol interference (ISI) from a data signal received via a band-limited (or otherwise non-ideal) channel. A first PAM-4 DFE architecture has low latency from the output of the samplers to the application of the first DFE tap feedback to the input signal. This is accomplished by not decoding the sampler outputs in order to generate the feedback signal for the first DFE tap. Rather, weighted versions of the raw sampler outputs are applied directly to the input signal without further analog or digital processing. Additional PAM-4 DFE architectures use the current symbol in addition to previous symbol(s) to determine the DFE feedback signal. Another architecture transmits PAM-4 signaling using non-uniform pre-emphasis. The non-uniform pre-emphasis allows a speculative DFE receiver to resolve the transmitted PAM-4 signals with fewer comparators/samplers.
    Type: Application
    Filed: November 12, 2019
    Publication date: May 14, 2020
    Inventors: Masum HOSSAIN, Nhat NGUYEN, Yikui Jen DONG, Arash ZARGARAN-YAZD, Wendemagegnehu BEYENE
  • Patent number: 10516427
    Abstract: Decision feedback equalization (DFE) is used to help reduce inter-symbol interference (ISI) from a data signal received via a band-limited (or otherwise non-ideal) channel. A first PAM-4 DFE architecture has low latency from the output of the samplers to the application of the first DFE tap feedback to the input signal. This is accomplished by not decoding the sampler outputs in order to generate the feedback signal for the first DFE tap. Rather, weighted versions of the raw sampler outputs are applied directly to the input signal without further analog or digital processing. Additional PAM-4 DFE architectures use the current symbol in addition to previous symbol(s) to determine the DFE feedback signal. Another architecture transmits PAM-4 signaling using non-uniform pre-emphasis. The non-uniform pre-emphasis allows a speculative DFE receiver to resolve the transmitted PAM-4 signals with fewer comparators/samplers.
    Type: Grant
    Filed: October 12, 2016
    Date of Patent: December 24, 2019
    Assignee: Rambus Inc.
    Inventors: Masum Hossain, Nhat Nguyen, Yikui Jen Dong, Arash Zargaran-Yazd, Wendemagegnehu Beyene
  • Publication number: 20180248577
    Abstract: Decision feedback equalization (DFE) is used to help reduce inter-symbol interference (ISI) from a data signal received via a band-limited (or otherwise non-ideal) channel. A first PAM-4 DFE architecture has low latency from the output of the samplers to the application of the first DFE tap feedback to the input signal. This is accomplished by not decoding the sampler outputs in order to generate the feedback signal for the first DFE tap. Rather, weighted versions of the raw sampler outputs are applied directly to the input signal without further analog or digital processing. Additional PAM-4 DFE architectures use the current symbol in addition to previous symbol(s) to determine the DFE feedback signal. Another architecture transmits PAM-4 signaling using non-uniform pre-emphasis. The non-uniform pre-emphasis allows a speculative DFE receiver to resolve the transmitted PAM-4 signals with fewer comparators/samplers.
    Type: Application
    Filed: October 12, 2016
    Publication date: August 30, 2018
    Inventors: Masum HOSSAIN, Nhat NGUYEN, Yikui Jen DONG, Arash ZARGARAN-YAZD, Wendemagegnehu BEYENE
  • Patent number: 10026666
    Abstract: Disclosed is a package-on-package (PoP) assembly comprises a two-tiered windowed ball grid array (BGA) and a system on a chip (SoC) package. Window openings in the two tiers of the BGA are of different sizes to allow for wirebond landing pads on the first tier. A DRAM die is mounted to the BGA flipped over (i.e., wirebond pads facing the BGA package.) The DRAM die is wirebonded through the window in the BGA. For multi-channel systems and higher memory capacity, the DRAM die will have low-cost through-silicon vias (TSVs) that connect to stacked DRAM die(s). The stacked DRAM dies may be offset or rotated to align active TSVs with passive TSVs thereby enabling unique connections to certain DRAM dies in the stack.
    Type: Grant
    Filed: October 14, 2014
    Date of Patent: July 17, 2018
    Assignee: Rambus Inc.
    Inventors: Nitin Juneja, Wendemagegnehu Beyene, David A. Secker, Ely K. Tsern
  • Patent number: 9471518
    Abstract: A multi-modal memory interface that supports each of current-mode and voltage-mode signaling by a memory controller with a memory which includes one or more memory devices. In a first type of system, the memory interface is configured to provide differential current-mode signaling from the memory controller to a first type of memory, and differential voltage-mode signaling from the memory to the memory controller. In contrast, in a second type of system, the memory interface is configured to provide single-ended voltage-mode signaling from the memory controller to the memory, and single-ended voltage-mode signaling from a second type of memory to the memory controller. To support these different types of systems, the memory controller couples different types of drivers to each I/O pad. The resulting capacitance is reduced by sharing components between these drivers. Moreover, in some embodiments, the memory interface is implemented using “near-ground” current-mode and voltage-mode signaling techniques.
    Type: Grant
    Filed: November 2, 2012
    Date of Patent: October 18, 2016
    Assignee: Rambus Inc.
    Inventors: Amir Amirkhany, Wendemagegnehu Beyene
  • Patent number: 9165615
    Abstract: Encoder and decoder circuits that encode and decode a series of data words to/from a series of code words. The data words include L symbols. The code words include M symbols, where M is larger than L. A set of tightly coupled M links to convey respective symbols in each of the series of code words. The code words are selected such that between every two consecutive code words in a series of code words, an equal number of transitions from low to high and high to low occur on a subset of the M-links.
    Type: Grant
    Filed: March 14, 2011
    Date of Patent: October 20, 2015
    Assignee: Rambus Inc.
    Inventors: Amir Amirkhany, Aliazam Abbasfar, Kambiz Kaviani, Wendemagegnehu Beyene, Carl Werner
  • Publication number: 20150108656
    Abstract: Disclosed is a package-on-package (PoP) assembly comprises a two-tiered windowed ball grid array (BGA) and a system on a chip (SoC) package. Window openings in the two tiers of the BGA are of different sizes to allow for wirebond landing pads on the first tier. A DRAM die is mounted to the BGA flipped over (i.e., wirebond pads facing the BGA package.) The DRAM die is wirebonded through the window in the BGA. For multi-channel systems and higher memory capacity, the DRAM die will have low-cost through-silicon vias (TSVs) that connect to stacked DRAM die(s). The stacked DRAM dies may be offset or rotated to align active TSVs with passive TSVs thereby enabling unique connections to certain DRAM dies in the stack.
    Type: Application
    Filed: October 14, 2014
    Publication date: April 23, 2015
    Inventors: Nitin Juneja, Wendemagegnehu Beyene, David A. Secker, Ely K. Tsern
  • Patent number: 8553752
    Abstract: Embodiments of a system for determining and optimizing the performance a signaling system are described. During operation, the system captures or measures a single-bit response (SBR) for the signaling system. Next, the system constructs an idealized inter-symbol-interference-free (ISI-free) SBR for the signaling system which is substantially free of inter-symbol-interference (ISI). The system then calculates an ISI-residual from the captured SBR and the idealized ISI-free SBR. Next, the system constructs a calibration bit pattern for the signaling system that is based substantially on the ISI-residual. Finally, the system uses the calibration bit pattern to calibrate, optimize and determine an aspect of the performance of the signaling system.
    Type: Grant
    Filed: January 30, 2008
    Date of Patent: October 8, 2013
    Assignee: Rambus Inc.
    Inventors: Wendemagegnehu Beyene, Kevin S. Donnelly, Mark A. Horowitz
  • Publication number: 20130051162
    Abstract: Encoder and decoder circuits that encode and decode a series of data words to/from a series of code words. The data words include L symbols. The code words include M symbols, where M is larger than L. A set of tightly coupled M links to convey respective symbols in each of the series of code words. The code words are selected such that between every two consecutive code words in a series of code words, an equal number of transitions from low to high and high to low occur on a subset of the M-links.
    Type: Application
    Filed: March 14, 2011
    Publication date: February 28, 2013
    Applicant: RAMBUS INC.
    Inventors: Amir Amirkhany, Aliazam Abbasfar, Kambiz Kaviani, Wendemagegnehu Beyene, Carl Werner
  • Publication number: 20120306568
    Abstract: Embodiments reduce crosstalk between multiple interconnects in a printed circuit board environment. Further, embodiments perform frequency-dependent modal decomposition of characteristics of two or more interconnects spanning one or more integrated circuits on an interconnect substrate. In addition, each interconnect includes one or more cascaded coupled traces, where the cascaded coupled traces have one or more discontinuities in a heterogeneous medium.
    Type: Application
    Filed: June 5, 2012
    Publication date: December 6, 2012
    Applicant: RAMBUS INC.
    Inventors: Wendemagegnehu Beyene, Pavle Milosevic
  • Publication number: 20110033007
    Abstract: A system comprising: a first integrated circuit device having a multi-band transmission circuit; second and third integrated circuit devices having respective multi-band reception circuits; and a signaling link including a first stub coupled to the multi-band transmission circuit to receive a multi-band signal therefrom, second and third stubs coupled to the multi-band reception circuits of the second and third integrated circuit devices, respectively, to deliver the multi-band signal thereto, and a plurality of channel segments that extend between the first, second and third stubs to convey the multi-band transmission signal therebetween, and wherein at least one of a physical length, impedance or propagation constant of at least one of the first stub, second stub, third stub or channel segment of the plurality of channel segments is selected to spectrally position a frequency-interval exhibiting attenuated frequency response on the signaling link such that multiple passbands separated by the frequency-inter
    Type: Application
    Filed: November 12, 2008
    Publication date: February 10, 2011
    Inventors: Jared L. Zerbe, Vladimir M. Stojanovic, Ravindranath Kollipara, Wendemagegnehu Beyene, Amir Arnirkhany, Bruno Garlepp
  • Publication number: 20100296566
    Abstract: Embodiments of a system for determining and optimizing the performance a signaling system are described. During operation, the system captures or measures a single-bit response (SBR) for the signaling system. Next, the system constructs an idealized inter-symbol-interference-free (ISI-free) SBR for the signaling system which is substantially free of inter-symbol-interference (ISI). The system then calculates an ISI-residual from the captured SBR and the idealized ISI-free SBR. Next, the system constructs a calibration bit pattern for the signaling system that is based substantially on the ISI-residual. Finally, the system uses the calibration bit pattern to calibrate, optimize and determine an aspect of the performance of the signaling system.
    Type: Application
    Filed: January 30, 2008
    Publication date: November 25, 2010
    Applicant: RAMBUS INC.
    Inventors: Wendemagegnehu Beyene, Kevin S. Donnelly, Mark A. Horowitz