公开(公告)号：US20210006341A1

公开(公告)日：2021-01-07

申请号：US16930526

申请日：2020-07-16

Applicant: Rambus Inc.

Inventor： Andrew Ho ,  Vladimir Stojanovic ,  Bruno W. Garlepp ,  Fred F. Chen

IPC: H04B17/29 ,  H04L25/03 ,  H04L27/01 ,  H04B17/21 ,  G01R31/317 ,  H04L1/20 ,  H04L1/24 ,  H04L7/033 ,  G06F11/08

Abstract: Described are methods and circuits for margin testing digital receivers. These methods and circuits prevent margins from collapsing in response to erroneously received data and can thus be used in receivers that employ historical data to reduce intersymbol interference (ISI). Some embodiments detect receive errors for input data streams of unknown patterns and can thus be used for in-system margin testing. Such systems can be adapted to dynamically alter system parameters during device operation to maintain adequate margins despite fluctuations in the system noise environment due to e.g. temperature and supply-voltage changes. Also described are methods of plotting and interpreting filtered and unfiltered error data generated by the disclosed methods and circuits. Some embodiments filter error data to facilitate pattern-specific margin testing.

公开(公告)号：US10225111B2

公开(公告)日：2019-03-05

申请号：US15907205

申请日：2018-02-27

Applicant: Rambus Inc.

Inventor： Vladimir M. Stojanovic ,  Andrew C. Ho ,  Anthony Bessios ,  Bruno W. Garlepp ,  Grace Tsang ,  Mark A. Horowitz ,  Jared L. Zerbe ,  Jason C. Wei

IPC: H04L25/03 ,  H04L25/06 ,  H04L25/497 ,  H04L7/027

Abstract: A signaling system is described. The signaling system comprises a transmit device, a receive device including a partial response receive circuit, and a signaling path coupling the transmit device and the receive device. The receive device observes an equalized signal from the signaling path, and includes circuitry to use feedback from the most recent previously resolved symbol to sample a currently incoming symbol. The transmit device equalizes transmit data to transmit the equalized signal, by applying weighting based on one or more data values not associated with the most recent previously resolved symbol value.

公开(公告)号：US10193642B2

公开(公告)日：2019-01-29

申请号：US15368805

申请日：2016-12-05

Applicant: Rambus Inc.

Inventor： Andrew Ho ,  Vladimir Stojanovic ,  Bruno W. Garlepp ,  Fred F. Chen

IPC: H04B17/29 ,  H04L25/03 ,  H04L27/01 ,  G01R31/317 ,  H04L1/20 ,  H04L1/24 ,  H04L7/033 ,  G06F11/08 ,  H04B17/21 ,  H04L7/04 ,  H04L7/10

Abstract: Described are methods and circuits for margin testing digital receivers. These methods and circuits prevent margins from collapsing in response to erroneously received data, and can thus be used in receivers that employ historical data to reduce intersymbol interference (ISI). Some embodiments detect receive errors for input data streams of unknown patterns, and can thus be used for in-system margin testing. Such systems can be adapted to dynamically alter system parameters during device operation to maintain adequate margins despite fluctuations in the system noise environment due to e.g. temperature and supply-voltage changes. Also described are methods of plotting and interpreting filtered and unfiltered error data generated by the disclosed methods and circuits. Some embodiments filter error data to facilitate pattern-specific margin testing.

公开(公告)号：US09917708B2

公开(公告)日：2018-03-13

申请号：US15092435

申请日：2016-04-06

Applicant: Rambus Inc.

Inventor： Vladimir M. Stojanovic ,  Andrew C. Ho ,  Anthony Bessios ,  Bruno W. Garlepp ,  Grace Tsang ,  Mark A. Horowitz ,  Jared L. Zerbe ,  Jason C. Wei

IPC: H01L25/03 ,  H04L25/03 ,  H04L25/06 ,  H04L25/497 ,  H04L7/027

CPC classification number: H04L25/03057 ,  H04L7/0276 ,  H04L25/063 ,  H04L25/497 ,  H04L2025/03369 ,  H04L2025/03503

Abstract: A signaling system is described. The signaling system comprises a transmit device, a receive device including a partial response receive circuit, and a signaling path coupling the transmit device and the receive device. The receive device observes an equalized signal from the signaling path, and includes circuitry to use feedback from the most recent previously resolved symbol to sample a currently incoming symbol. The transmit device equalizes transmit data to transmit the equalized signal, by applying weighting based on one or more data values not associated with the most recent previously resolved symbol value.

公开(公告)号：US20170149513A1

公开(公告)日：2017-05-25

申请号：US15368805

申请日：2016-12-05

Applicant: Rambus Inc.

Inventor： Andrew Ho ,  Vladimir Stojanovic ,  Bruno W. Garlepp ,  Fred F. Chen

IPC: H04B17/29 ,  H04L25/03

CPC classification number: H04B17/29 ,  G01R31/31711 ,  G06F11/08 ,  H04B17/21 ,  H04L1/20 ,  H04L1/241 ,  H04L1/242 ,  H04L7/033 ,  H04L7/043 ,  H04L7/10 ,  H04L25/03006 ,  H04L25/03057 ,  H04L25/03146 ,  H04L25/03949 ,  H04L27/01

Abstract: Described are methods and circuits for margin testing digital receivers. These methods and circuits prevent margins from collapsing in response to erroneously received data, and can thus be used in receivers that employ historical data to reduce intersymbol interference (ISI). Some embodiments detect receive errors for input data streams of unknown patterns, and can thus be used for in-system margin testing. Such systems can be adapted to dynamically alter system parameters during device operation to maintain adequate margins despite fluctuations in the system noise environment due to e.g. temperature and supply-voltage changes. Also described are methods of plotting and interpreting filtered and unfiltered error data generated by the disclosed methods and circuits. Some embodiments filter error data to facilitate pattern-specific margin testing.

公开(公告)号：US11233589B2

公开(公告)日：2022-01-25

申请号：US17102779

申请日：2020-11-24

Applicant: Rambus Inc.

Inventor： Andrew Ho ,  Vladimir Stojanovic ,  Bruno W. Garlepp ,  Fred F. Chen

IPC: H04B17/29 ,  H04L25/03 ,  H04L27/01 ,  H04B17/21 ,  G01R31/317 ,  H04L1/20 ,  H04L1/24 ,  H04L7/033 ,  G06F11/08 ,  H04L7/04 ,  H04L7/10

Abstract: Described are methods and circuits for margin testing digital receivers. These methods and circuits prevent margins from collapsing in response to erroneously received data and can thus be used in receivers that employ historical data to reduce intersymbol interference (ISI). Some embodiments detect receive errors for input data streams of unknown patterns and can thus be used for in-system margin testing. Such systems can be adapted to dynamically alter system parameters during device operation to maintain adequate margins despite fluctuations in the system noise environment due to e.g. temperature and supply-voltage changes. Also described are methods of plotting and interpreting filtered and unfiltered error data generated by the disclosed methods and circuits. Some embodiments filter error data to facilitate pattern-specific margin testing.

公开(公告)号：US10764093B2

公开(公告)日：2020-09-01

申请号：US15165134

申请日：2016-05-26

Applicant: Rambus Inc.

Inventor： Brian S. Leibowitz ,  Bruno W. Garlepp

IPC: H04L25/03 ,  H04L1/24 ,  G01R31/317 ,  H04L1/20 ,  H04L7/033 ,  H04J11/00 ,  H04L5/00

Abstract: Described are methods and circuits for margin testing digital receivers. These methods and circuits prevent margins from collapsing in response to erroneously received data, and can thus be used in receivers that employ historical data to reduce intersymbol interference (ISI). Some embodiments allows feedback timing to be adjusted independent of the sample timing to measure the effects of some forms of phase misalignment and jitter.

公开(公告)号：US10310999B2

公开(公告)日：2019-06-04

申请号：US15702987

申请日：2017-09-13

Applicant: Rambus Inc.

Inventor： Jared LeVan Zerbe ,  Kevin S. Donnelly ,  Stefanos Sidiropoulos ,  Donald C. Stark ,  Mark A. Horowitz ,  Leung Yu ,  Roxanne Vu ,  Jun Kim ,  Bruno W. Garlepp ,  Tsyr-Chyang Ho ,  Benedict Chung-Kwong Lau

IPC: G06F13/364 ,  G06F13/42 ,  G06F1/10 ,  G06F13/16 ,  H04L7/00 ,  G11C7/10 ,  G06F12/02 ,  G06F3/06 ,  G06F13/40 ,  H04L7/033

Abstract: An integrated circuit device includes a transmitter circuit operable to transmit a timing signal over a first wire to a DRAM. The DRAM receives a first signal having a balanced number of logical zero-to-one transitions and one-to-zero transitions and samples the first signal at a rising edge of the timing signal to produce a respective sampled value. The device further includes a receiver circuit to receive the respective sampled value from the DRAM over a plurality of wires separate from the first wire. In a first mode, the transmitter circuit repeatedly transmits incrementally offset versions of the timing signal to the DRAM until sampled values received from the DRAM change from a logical zero to a logical one or vice versa; and in a second mode, it transmits write data over the plurality of wires to the DRAM according to a write timing offset generated based on the sampled values.

公开(公告)号：US20160308693A1

公开(公告)日：2016-10-20

申请号：US15092435

申请日：2016-04-06

Applicant: Rambus Inc.

Inventor： Vladimir M. Stojanovic ,  Andrew C. Ho ,  Anthony Bessios ,  Bruno W. Garlepp ,  Grace Tsang ,  Mark A. Horowitz ,  Jared L. Zerbe ,  Jason C. Wei

IPC: H04L25/03

CPC classification number: H04L25/03057 ,  H04L7/0276 ,  H04L25/063 ,  H04L25/497 ,  H04L2025/03369 ,  H04L2025/03503

Abstract: A signaling system is described. The signaling system comprises a transmit device, a receive device including a partial response receive circuit, and a signaling path coupling the transmit device and the receive device. The receive device observes an equalized signal from the signaling path, and includes circuitry to use feedback from the most recent previously resolved symbol to sample a currently incoming symbol. The transmit device equalizes transmit data to transmit the equalized signal, by applying weighting based on one or more data values not associated with the most recent previously resolved symbol value.

公开(公告)号：US09407473B2

公开(公告)日：2016-08-02

申请号：US14683081

申请日：2015-04-09

Applicant: Rambus Inc.

Inventor： Vladimir M. Stojanovic ,  Andrew C. Ho ,  Anthony Bessios ,  Bruno W. Garlepp ,  Grace Tsang ,  Mark A. Horowitz ,  Jared L. Zerbe ,  Jason C. Wei

IPC: H04L25/03 ,  H04L25/06 ,  H04L25/497

CPC classification number: H04L25/03057 ,  H04L7/0276 ,  H04L25/063 ,  H04L25/497 ,  H04L2025/03369 ,  H04L2025/03503

Abstract: A signaling system is described. The signaling system comprises a transmit device, a receive device including a partial response receive circuit, and a signaling path coupling the transmit device and the receive device. The receive device observes an equalized signal from the signaling path, and includes circuitry to use feedback from the most recent previously resolved symbol to sample a currently incoming symbol. The transmit device equalizes transmit data to transmit the equalized signal, by applying weighting based on one or more data values not associated with the most recent previously resolved symbol value.