Patents by Inventor Kaushik Sheth
Kaushik Sheth 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).
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Publication number: 20230197029Abstract: A display system comprising a plurality of display controller circuits controlling a like number of independent segments of pixel drive circuits of a backplane. Each pixel drive circuit comprises a memory element and associated pixel drive circuitry. The segments of the backplane may be organized vertically. The word line for the memory cells of a first segment of pixel drive circuits passes underneath a second segment of pixel drive circuits without directly interacting with the pixel drive circuits of the second segment in order to reach the pixel drive circuits of the first segment. The plurality of display controller circuits operate asynchronously but are kept at the same frame rate by an external signal such as Vsync.Type: ApplicationFiled: December 16, 2022Publication date: June 22, 2023Inventors: Bo Li, Kaushik Sheth
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Publication number: 20230147106Abstract: A backplane design for delivering image data in an efficient manner to a memory cell forming a part of a pixel driver comprises a word line design and a column data register release signal delivery design that are speed matched and a complementary bit line delivery design that is speed matched to a row decoder signal circuit operative to pull a word line driver to a state to enable the memory circuits of that row to receive data from the column drivers for each column. The speed matching is effective over a range of operating temperatures because the circuit designs are substantially identical.Type: ApplicationFiled: January 5, 2023Publication date: May 11, 2023Inventors: Bo Li, Kaushik Sheth, Edwin Lyle Hudson
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Patent number: 11568802Abstract: A backplane suitable to pulse width modulate an array of emissive pixels with a current that is substantially constant over a wide range of temperatures. A current control circuit provides means to provide a constant current to an array of current mirror pixel drive elements. The current control circuit comprises a thermally stable bias resistor and a thermally stable band-gap voltage source to provide thermally stable controls and a large L p-channel reference current FET with an associated large L n-channel bias FET configured to provide a reference current at a required voltage to the gate of a large L p-channel current source FET. The current control circuit and the current mirror pixel drive elements are similar circuits with one current control circuit able to control a substantial number of pixel drive elements.Type: GrantFiled: January 26, 2022Date of Patent: January 31, 2023Assignee: Google LLCInventors: Bo Li, Kaushik Sheth
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Patent number: 11538431Abstract: A display system comprising a plurality of display controller circuits controlling a like number of independent segments of pixel drive circuits of a backplane. Each pixel drive circuit comprises a memory element and associated pixel drive circuitry. The segments of the backplane may be organized vertically. The word line for the memory cells of a first segment of pixel drive circuits passes underneath a second segment of pixel drive circuits without directly interacting with the pixel drive circuits of the second segment in order to reach the pixel drive circuits of the first segment. The plurality of display controller circuits operate asynchronously but are kept at the same frame rate by an external signal such as Vsync.Type: GrantFiled: June 22, 2021Date of Patent: December 27, 2022Assignee: Google LLCInventors: Bo Li, Kaushik Sheth
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Publication number: 20220165208Abstract: A method for providing gray scale for an array of current emissive devices sensitive to the current level driving them, such as an LEDs, is disclosed. Multiple current sources are operated in parallel for each emissive device with the on/off state of each of the multiple current source controlled by a memory circuit. Means for pulse width modulating the array of current sensitive devices to enable greater control over gray scale is presented.Type: ApplicationFiled: November 9, 2021Publication date: May 26, 2022Inventors: Kaushik Sheth, Bo Li, Edwin Lyle Hudson, Jeffrey Li, Robert Lo, David Charles McDonald
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Publication number: 20220148497Abstract: A backplane suitable to pulse width modulate an array of emissive pixels with a current that is substantially constant over a wide range of temperatures. A current control circuit provides means to provide a constant current to an array of current mirror pixel drive elements. The current control circuit comprises a thermally stable bias resistor and a thermally stable band-gap voltage source to provide thermally stable controls and a large L p-channel reference current FET with an associated large L n-channel bias FET configured to provide a reference current at a required voltage to the gate of a large L p-channel current source FET. The current control circuit and the current mirror pixel drive elements are similar circuits with one current control circuit able to control a substantial number of pixel drive elements.Type: ApplicationFiled: January 26, 2022Publication date: May 12, 2022Inventors: Bo Li, Kaushik Sheth
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Publication number: 20220130344Abstract: A backplane design for delivering image data in an efficient manner to a memory cell forming a part of a pixel drive circuit comprises a word line design and a column data register release signal delivery design that are speed matched and a complementary bit line delivery design that is speed matched to a row decoder signal circuit operative to pull a word line driver to a state to enable the memory circuits of that row to receive data from the column drivers for each column. The speed matching is effective over a range of operating temperatures because the circuit designs are substantially identical.Type: ApplicationFiled: January 5, 2022Publication date: April 28, 2022Inventors: Bo Li, Kaushik Sheth, Edwin Lyle Hudson
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Patent number: 11270634Abstract: A backplane suitable to pulse width modulate an array of emissive pixels with a current that is substantially constant over a wide range of temperatures. A current control circuit provides means to provide a constant current to an array of current mirror pixel drive elements. The current control circuit comprises a thermally stable bias resistor and a thermally stable band-gap voltage source to provide thermally stable controls and a large L p-channel reference current FET with an associated large L n-channel bias FET configured to provide a reference current at a required voltage to the gate of a large L p-channel current source FET. The current control circuit and the current mirror pixel drive elements are similar circuits with one current control circuit able to control a substantial number of pixel drive elements.Type: GrantFiled: January 26, 2021Date of Patent: March 8, 2022Assignee: JASPER DISPLAY CORP.Inventors: Bo Li, Kaushik Sheth
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Publication number: 20210407455Abstract: A display system comprising a plurality of display controller circuits controlling a like number of independent segments of pixel drive circuits of a backplane. Each pixel drive circuit comprises a memory element and associated pixel drive circuitry. The segments of the backplane may be organized vertically. The word line for the memory cells of a first segment of pixel drive circuits passes underneath a second segment of pixel drive circuits without directly interacting with the pixel drive circuits of the second segment in order to reach the pixel drive circuits of the first segment. The plurality of display controller circuits operate asynchronously but are kept at the same frame rate by an external signal such as Vsync.Type: ApplicationFiled: June 22, 2021Publication date: December 30, 2021Inventors: Bo Li, Kaushik Sheth
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Publication number: 20210201771Abstract: A backplane suitable to pulse width modulate an array of emissive pixels with a current that is substantially constant over a wide range of temperatures. A current control circuit provides means to provide a constant current to an array of current mirror pixel drive elements. The current control circuit comprises a thermally stable bias resistor and a thermally stable band-gap voltage source to provide thermally stable controls and a large L p-channel reference current FET with an associated large L n-channel bias FET configured to provide a reference current at a required voltage to the gate of a large L p-channel current source FET. The current control circuit and the current mirror pixel drive elements are similar circuits with one current control circuit able to control a substantial number of pixel drive elements.Type: ApplicationFiled: January 26, 2021Publication date: July 1, 2021Inventors: Bo Li, Kaushik Sheth
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Patent number: 11030942Abstract: A backplane operative to drive an array of emissive elements forming a part of a display or display like manufacturing device is disclosed. Each emissive element is mounted to a common pad supplied with current from a plurality of pixel drive elements, wherein each pixel drive element is controlled by a resident memory cell. The plurality of pixel drive elements is organized into a block similar to other blocks of pixel drive elements across the array. The common pad may be driven by a larger or lesser number of pixel drive elements than are present in a single block of pixel drive elements. If not needed, specific pixel drive elements present in a single block may be disabled through a mask change.Type: GrantFiled: November 11, 2019Date of Patent: June 8, 2021Assignee: JASPER DISPLAY CORPORATIONInventors: Bo Li, Kaushik Sheth
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Backplane suitable to form part of an emissive pixel array and system and methods of modulating same
Patent number: 10957272Abstract: A backplane operative to drive an array of emissive pixel elements is disclosed. Each pixel element comprises a pixel circuit drive element and an emissive element, wherein the pixel circuit drive element comprises a memory cell, a current source element, and a modulation element. The present invention improves on an emissive display by providing a backplane and modulation system that enables fabrication of multi-color or monochrome LED display systems that operate efficiently and without objectionable image artifacts. One aspect of the present invention is to realize the backplane in a single crystal silicon process with a minimum number of metal layers while providing each color with a suitable operating voltage and drive current.Type: GrantFiled: February 26, 2020Date of Patent: March 23, 2021Assignee: JASPER DISPLAY CORP.Inventors: Bo Li, Kaushik Sheth, James Michael Stover, Edwin Lyle Hudson, David Charles McDonald, Jeffrey Tang Fung Li -
BACKPLANE SUITABLE TO FORM PART OF AN EMISSIVE PIXEL ARRAY AND SYSTEM AND METHODS OF MODULATING SAME
Publication number: 20200193929Abstract: A backplane operative to drive an array of emissive pixel elements is disclosed. Each pixel element comprises a pixel circuit drive element and an emissive element, wherein the pixel circuit drive element comprises a memory cell, a current source element, and a modulation element. The present invention improves on an emissive display by providing a backplane and modulation system that enables fabrication of multi-color or monochrome LED display systems that operate efficiently and without objectionable image artifacts. One aspect of the present invention is to realize the backplane in a single crystal silicon process with a minimum number of metal layers while providing each color with a suitable operating voltage and drive current.Type: ApplicationFiled: February 26, 2020Publication date: June 18, 2020Inventors: Bo Li, Kaushik Sheth, James Michael Stover, Edwin Lyle Hudson, David Charles McDonald, Jeffrey Tang Fung Li -
Backplane suitable to form part of an emissive pixel array and system and methods of modulating same
Patent number: 10629153Abstract: A backplane operative to drive an array of emissive pixel elements is disclosed. Each pixel element comprises a pixel circuit drive element and an emissive element, wherein the pixel circuit drive element comprises a memory cell, a current source element, and a modulation element. The present invention improves on an emissive display by providing a backplane and modulation system that enables fabrication of multi-color or monochrome LED display systems that operate efficiently and without objectionable image artifacts. One aspect of the present invention is to realize the backplane in a single crystal silicon process with a minimum number of metal layers while providing each color with a suitable operating voltage and drive current.Type: GrantFiled: October 5, 2018Date of Patent: April 21, 2020Assignee: JASPER DISPLAY CORP.Inventors: Bo Li, Kaushik Sheth, James Michael Stover, Edwin Lyle Hudson, David Charles McDonald, Jeffrey Tang Fung Li -
Publication number: 20200098307Abstract: A backplane suitable to pulse width modulate an array of emissive pixels with a current that is substantially constant over a wide range of temperatures. A current control circuit provides means to provide a constant current to an array of current mirror pixel drive elements. The current control circuit comprises a thermally stable bias resistor and a thermally stable band-gap voltage source to provide thermally stable controls and a large L p-channel reference current FET with an associated large L n-channel bias FET configured to provide a reference current at a required voltage to the gate of a large L p-channel current source FET. The current control circuit and the current mirror pixel drive elements are similar circuits with one current control circuit able to control a substantial number of pixel drive elements.Type: ApplicationFiled: November 11, 2019Publication date: March 26, 2020Inventors: Bo Li, Kaushik Sheth
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BACKPLANE SUITABLE TO FORM PART OF AN EMISSIVE PIXEL ARRAY AND SYSTEM AND METHODS OF MODULATING SAME
Publication number: 20190114987Abstract: A backplane operative to drive an array of emissive pixel elements is disclosed. Each pixel element comprises a pixel circuit drive element and an emissive element, wherein the pixel circuit drive element comprises a memory cell, a current source element, and a modulation element. The present invention improves on an emissive display by providing a backplane and modulation system that enables fabrication of multi-color or monochrome LED display systems that operate efficiently and without objectionable image artifacts. One aspect of the present invention is to realize the backplane in a single crystal silicon process with a minimum number of metal layers while providing each color with a suitable operating voltage and drive current.Type: ApplicationFiled: October 5, 2018Publication date: April 18, 2019Inventors: Bo Li, Kaushik Sheth, James Michael Stover, Edwin Lyle Hudson, David Charles McDonald, Jeffrey Tang Fung Li -
Patent number: 8006216Abstract: Techniques are disclosed for performing topologically planar routing of System in Packages (SiPs). A routing graph can be represented by a particle-insertion-based constraint Delaunay triangulation (PCDT) and its dual. A dynamic search routing may be performed using a DS* routing algorithm to determine the shortest path on the dual graph between a start point and an end point. Based on a dynamic pushing technique, net ordering problems may be solved. A first wire can be topologically routed. Dynamic search routing of a second wire may be performed. The first wire may be pushed or detoured in response to the dynamic searching routing of a second wire.Type: GrantFiled: June 6, 2008Date of Patent: August 23, 2011Assignee: Magma Design Automation, Inc.Inventors: Guoqiang Chen, Kaushik Sheth, Egino Sarto, Shenghua Liu