Patents by Inventor John Thomas Contreras

John Thomas Contreras 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).

  • Patent number: 11477881
    Abstract: To protect memory cards, such as SD type cards, and similar devices from Electrostatic Discharge (ESD), the input pads of the device include points along their edges that are aligned with correspond points on a conductive frame structure mounted adjacent the input pad to form a spark gap. The input pads are connected to a memory controller or other ASIC over signal lines that include a diode located between the input pad and the ASIC and a resistance located between the input pad and the diode. The resistance and diode are selected such that an ESD event at an input pad triggers a discharge across the spark gap before it is transmitted on to the ASIC, while also allowing a high data rate for signals along the signal line.
    Type: Grant
    Filed: June 26, 2019
    Date of Patent: October 18, 2022
    Assignee: SanDisk Technologies LLC
    Inventors: Albert Wallash, Shajith Musaliar Sirajudeen, John Thomas Contreras
  • Patent number: 11456022
    Abstract: The present disclosure generally relates to apparatuses and methods for transmission line termination. In one embodiment an apparatus includes a stack of uniform memory dies and a storage controller. Each uniform memory die in the stack of uniform memory dies couples to a transmission line in series through wire bonds to form a transmission path. Each memory die includes an on-die termination resistance circuit connected to the transmission line. The on-die termination resistance circuit provides a minimum termination resistance. The storage controller addresses a target uniform memory die of the stack of uniform memory dies for an operation. The storage controller enables the on-die termination resistance circuits of a plurality of uniform memory dies along the transmission path. The storage controller transmits a data signal for the operation to the target uniform memory die with the on-die termination resistance circuit enabled for the plurality of uniform memory dies.
    Type: Grant
    Filed: June 30, 2020
    Date of Patent: September 27, 2022
    Assignee: Western Digital Technologies, Inc.
    Inventors: John Thomas Contreras, Srinivas Rajendra, Sayed Mobin, Rehan Ahmed Zakai
  • Patent number: 11303276
    Abstract: An active termination circuit comprising an input node connected to a transmission line, a first transistor, and a second transistor. The transmission line supplies a signal to the input node. The first transistor is diode connected between a high voltage supply and the input node. The first transistor terminates the signal when the signal is at a low logic level. The second transistor is diode connected between the input node and a low voltage supply. The second transistor terminates the signal when the signal is at a high logic level.
    Type: Grant
    Filed: February 26, 2021
    Date of Patent: April 12, 2022
    Assignee: WESTERN DIGITAL TECHNOLOGIES, INC.
    Inventors: John Thomas Contreras, Rehan Ahmed Zakai, Srinivas Rajendra, Venkatesh Prasad Ramachandra
  • Patent number: 11302645
    Abstract: A circuit interconnect for high bandwidth and high die-count memory stacks. The circuit interconnect may include a first ground trace, a first signal trace, a second ground trace, and a second signal trace. The first ground trace may reside in a first layer of a multilayer printed circuit board. The first signal trace may be positioned adjacent to the first ground trace within the first layer. The second ground trace may reside within a second layer of the multilayer printed circuit board. The second signal trace may be positioned adjacent to the second ground trace within the second layer.
    Type: Grant
    Filed: June 30, 2020
    Date of Patent: April 12, 2022
    Assignee: Western Digital Technologies, Inc.
    Inventors: John Thomas Contreras, Sayed Mobin, Daniel Oh, Rehan Ahmed Zakai
  • Publication number: 20220052688
    Abstract: An active termination circuit comprising an input node connected to a transmission line, a first transistor, and a second transistor. The transmission line supplies a signal to the input node. The first transistor is diode connected between a high voltage supply and the input node. The first transistor terminates the signal when the signal is at a low logic level. The second transistor is diode connected between the input node and a low voltage supply. The second transistor terminates the signal when the signal is at a high logic level.
    Type: Application
    Filed: February 26, 2021
    Publication date: February 17, 2022
    Inventors: John Thomas CONTRERAS, Rehan Ahmed ZAKAI, Srinivas RAJENDRA, Venkatesh Prasad RAMACHANDRA
  • Publication number: 20210407915
    Abstract: A circuit interconnect for high bandwidth and high die-count memory stacks. The circuit interconnect may include a first ground trace, a first signal trace, a second ground trace, and a second signal trace. The first ground trace may reside in a first layer of a multilayer printed circuit board. The first signal trace may be positioned adjacent to the first ground trace within the first layer. The second ground trace may reside within a second layer of the multilayer printed circuit board. The second signal trace may be positioned adjacent to the second ground trace within the second layer.
    Type: Application
    Filed: June 30, 2020
    Publication date: December 30, 2021
    Applicant: Western Digital Technologies, Inc.
    Inventors: John Thomas Contreras, Sayed Mobin, Daniel Oh, Rehan Ahmed Zakai
  • Publication number: 20210407565
    Abstract: The disclosed apparatuses and method provide transmission line termination. An apparatus include a stack of uniform memory dies and a storage controller. Each uniform memory die in the stack of uniform memory dies couples to a transmission line in series through wire bonds to form a transmission path. Each memory die includes an on-die termination resistance circuit connected to the transmission line. The on-die termination resistance circuit provides a minimum termination resistance. The storage controller addresses a target uniform memory die of the for an operation. The storage controller enables the on-die termination resistance circuits of a plurality of uniform memory dies along the transmission path. The storage controller transmits a data signal for the operation to the target uniform memory die with the on-die termination resistance circuit enabled for the plurality of uniform memory dies.
    Type: Application
    Filed: June 30, 2020
    Publication date: December 30, 2021
    Applicant: Western Digital Technologies, Inc.
    Inventors: John Thomas Contreras, Srinivas Rajendra, Sayed Mobin, Rehan Ahmed Zakai
  • Publication number: 20200413531
    Abstract: To protect memory cards, such as SD type cards, and similar devices from Electrostatic Discharge (ESD), the input pads of the device include points along their edges that are aligned with correspond points on a conductive frame structure mounted adjacent the input pad to form a spark gap. The input pads are connected to a memory controller or other ASIC over signal lines that include a diode located between the input pad and the ASIC and a resistance located between the input pad and the diode. The resistance and diode are selected such that an ESD event at an input pad triggers a discharge across the spark gap before it is transmitted on to the ASIC, while also allowing a high data rate for signals along the signal line.
    Type: Application
    Filed: June 26, 2019
    Publication date: December 31, 2020
    Applicant: SanDisk Technologies LLC
    Inventors: Albert Wallash, Shajith Musaliar Sirajudeen, John Thomas Contreras
  • Patent number: 10650850
    Abstract: A hard disk drive has a gas-bearing slider supporting a write head with an electrically conductive structure, like a spin-torque oscillator (STO), in the write gap, and dual independent interface voltage control (IVC) circuitry coupled to elements on the slider. A first IVC circuitry provides a bias voltage to the slider body to assure substantially zero electrical potential between the slider body and the disk to minimize slider-disk contact and lubrication pick-up. A second IVC circuitry operates independently of the first IVC circuitry and provides a bias voltage to the electrically conductive structure region to assure a negative potential of the electrically conductive structure region relative to the disk to minimize degradation of the slider overcoat and thus oxidation of the electrically conductive structure.
    Type: Grant
    Filed: June 11, 2019
    Date of Patent: May 12, 2020
    Assignee: Western Digital Technologies, Inc.
    Inventors: Sukumar Rajauria, Na Wang, Erhard Schreck, Qing Dai, John Thomas Contreras
  • Patent number: 10643676
    Abstract: An apparatus may include a controller die and a group of dies that communicate with each other via a transmission line. The transmission line includes a first portion integrated with a printed circuit board, and a second portion that includes a plurality of wire bonds bonded to input/output pads of the group of dies. The transmission line further includes a resistor circuit connected in series with the first portion and the second portion. The resistor circuit has a resistance value that provides reduced reflection coefficients over the transmission line between the first portion and the second portion. An on-die termination resistor circuit on the controller side is removed, with the inclusion of the resistor circuit.
    Type: Grant
    Filed: September 28, 2018
    Date of Patent: May 5, 2020
    Assignee: Western Digital Technologies, Inc.
    Inventors: Sayed Mobin, John Thomas Contreras, Pranav Balachander
  • Patent number: 10637533
    Abstract: An apparatus includes a controller die and a group of dies that communicate with each other via a transmission line. Less than all of the dies of the group includes a respective on-die termination resistance circuit coupled to the transmission line. In some embodiments, one of the dies that includes an on-die termination resistance circuit is an end die of the group. In particular embodiments, the end die is the only die of the group that includes an on-die termination resistance circuit coupled to the transmission line. Transmission frequencies or data rates may be increased without degrading signal quality by removing capacitance associated with on-die termination resistance circuits from at least one of the dies of the group.
    Type: Grant
    Filed: September 28, 2018
    Date of Patent: April 28, 2020
    Assignee: Western Digital Technologies, Inc.
    Inventors: John Thomas Contreras, Sayed Mobin, David Zhang, Gokul Kumar
  • Publication number: 20200106478
    Abstract: An apparatus includes a controller die and a group of dies that communicate with each other via a transmission line. Less than all of the dies of the group includes a respective on-die termination resistance circuit coupled to the transmission line. In some embodiments, one of the dies that includes an on-die termination resistance circuit is an end die of the group. In particular embodiments, the end die is the only die of the group that includes an on-die termination resistance circuit coupled to the transmission line. Transmission frequencies or data rates may be increased without degrading signal quality by removing capacitance associated with on-die termination resistance circuits from at least one of the dies of the group.
    Type: Application
    Filed: September 28, 2018
    Publication date: April 2, 2020
    Inventors: John Thomas Contreras, Sayed Mobin, David Zhang, Gokul Kumar
  • Publication number: 20200105318
    Abstract: An apparatus may include a controller die and a group of dies that communicate with each other via a transmission line. The transmission line includes a first portion integrated with a printed circuit board, and a second portion that includes a plurality of wire bonds bonded to input/output pads of the group of dies. The transmission line further includes a resistor circuit connected in series with the first portion and the second portion. The resistor circuit has a resistance value that provides reduced reflection coefficients over the transmission line between the first portion and the second portion. An on-die termination resistor circuit on the controller side is removed, with the inclusion of the resistor circuit.
    Type: Application
    Filed: September 28, 2018
    Publication date: April 2, 2020
    Inventors: Sayed Mobin, John Thomas Contreras, Pranav Balachander
  • Publication number: 20200065270
    Abstract: An apparatus comprising memory having at least one memory die is disclosed. The apparatus may comprises a memory controller. A data bus is coupled to the controller and the memory. A supplemental inductor is coupled to the data bus.
    Type: Application
    Filed: December 31, 2018
    Publication date: February 27, 2020
    Inventors: Md. Sayed Hossain Mobin, John Thomas Contreras, Pranav Balachander
  • Patent number: 10468073
    Abstract: An apparatus may include a controller die configured to communicate with a plurality of dies via a transmission line. The controller die may be configured to transmit a signal on the transmission line to a target die of the plurality of dies, or the target die may transmit a signal on the transmission line. The transmission may be dependent on an end die of the plurality of dies setting an end-die termination resistance to a low level. In situations where the target memory is receiving the signal, the target die may set target an on-die termination resistance to a high level. In situations where the target memory die is transmitting the signal, the target die may set an on-die termination resistance to a low level.
    Type: Grant
    Filed: December 29, 2017
    Date of Patent: November 5, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: John Thomas Contreras, Gokul Kumar
  • Patent number: 10461965
    Abstract: An active low-power termination circuit includes a first leg of a pair of transistors connected in series between the high supply level and ground, where the termination input is at a node between the transistors of the first node. A second leg uses a feed forward mechanism to control the voltage levels on the control gates of the transistors of the first leg. The second leg includes a second pair diode connected transistors, each of which is has its control gate connected to the control gate of the corresponding transistor in the first leg. A variable current source connected in series with the transistors of the second leg and is controlled by the output of a difference amplifier that has one input connect to an intermediate node of the second leg and a second input connected to a reference level intermediate to the high supply level and ground.
    Type: Grant
    Filed: September 28, 2018
    Date of Patent: October 29, 2019
    Assignee: Western Digital Technologies, Inc.
    Inventors: John Thomas Contreras, Rehan Zakai, Sayed Mobin
  • Publication number: 20190206450
    Abstract: An apparatus may include a controller die configured to communicate with a plurality of dies via a transmission line. The controller die may be configured to transmit a signal on the transmission line to a target die of the plurality of dies, or the target die may transmit a signal on the transmission line. The transmission may be dependent on an end die of the plurality of dies setting an end-die termination resistance to a low level. In situations where the target memory is receiving the signal, the target die may set target an on-die termination resistance to a high level. In situations where the target memory die is transmitting the signal, the target die may set an on-die termination resistance to a low level.
    Type: Application
    Filed: December 29, 2017
    Publication date: July 4, 2019
    Applicant: SanDisk Technologies LLC
    Inventors: John Thomas Contreras, Gokul Kumar
  • Patent number: 9837106
    Abstract: A two-dimensional magnetic recording (TDMR) disk drive has a gas-bearing slider that includes first and second sensors with a first cross-track spacing electrically coupled to a first magnetic shield, and third and fourth sensors with a different cross-track spacing electrically coupled to a second magnetic shield. The different spacings results in the first and third sensors and the second and fourth sensors having a cross-track spacing to accommodate for the effect of head skew. Each sensor is connected to an associated amplifier by a suspension trace and a common trace connected to its associated shield. Switching circuitry selects either the first and third amplifiers or the second and fourth amplifiers as the active pair depending on the radial location where the data is to be read. Thus the appropriate pair of sensors are aligned with the data tracks despite the presence of high head skew.
    Type: Grant
    Filed: June 5, 2017
    Date of Patent: December 5, 2017
    Assignee: Western Digital Technologies, Inc.
    Inventors: John Thomas Contreras, Howard Gordon Zolla
  • Publication number: 20150138663
    Abstract: A multiple-segment transmission line in a hard disk drive enables a wider optimization range of the slope, duration and amplitude of the transmission line overshoot (TLO) wave shape. There is a first segment with two traces for connection to the write driver circuitry, an end segment with two traces for connection to the write head and at least two intermediate segments. The number of traces in a segment is different from the number of traces in the segments to which the segment is immediately connected. There is an even number of traces in each segment and the traces in each segment are interleaved. The number of segments and the number of traces in each segment can be selected to achieve the desired impedance levels for the different segments to achieve the desired wave shape for the TLO. All of the traces on the transmission line are preferably coplanar.
    Type: Application
    Filed: November 18, 2013
    Publication date: May 21, 2015
    Applicant: HGST Netherlands B.V.
    Inventors: John Thomas Contreras, Nobumasa Nishiyama, Eiji Soga, Kazuhiro Nagaoka, Rehan Zakai
  • Patent number: 9036305
    Abstract: A multiple-segment transmission line in a hard disk drive enables a wider optimization range of the slope, duration and amplitude of the transmission line overshoot (TLO) wave shape. There is a first segment with two traces for connection to the write driver circuitry, an end segment with two traces for connection to the write head and at least two intermediate segments. The number of traces in a segment is different from the number of traces in the segments to which the segment is immediately connected. There is an even number of traces in each segment and the traces in each segment are interleaved. The number of segments and the number of traces in each segment can be selected to achieve the desired impedance levels for the different segments to achieve the desired wave shape for the TLO. All of the traces on the transmission line are preferably coplanar.
    Type: Grant
    Filed: November 18, 2013
    Date of Patent: May 19, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: John Thomas Contreras, Nobumasa Nishiyama, Eiji Soga, Kazuhiro Nagaoka, Rehan Zakai