Patents by Inventor Washington Lamar
Washington Lamar 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: 11967650Abstract: In one aspect, a diode includes a substrate having a first type dopant; a buried layer having a second type dopant and formed within the substrate; an epitaxial layer having the second type dopant and formed above the buried layer; and a plurality of regions having the first type dopant within the epitaxial layer. The plurality of regions includes a first region, a second region, and a third region. The diode also includes a base well having the first type dopant and located within the epitaxial layer and in contact with the third and fourth regions. In a reverse-bias mode, the diode is an electrostatic discharge (ESD) clamp and forms parasitic transistors comprising a first bipolar junction transistor (BJT), a second BJT and a third BJT.Type: GrantFiled: May 5, 2022Date of Patent: April 23, 2024Assignee: Allegro MicroSystems, LLCInventors: Sagar Saxena, Washington Lamar, Maxim Klebanov, Chung C. Kuo, Sebastian Courtney, Sundar Chetlur
-
Publication number: 20230361223Abstract: In one aspect, a diode includes a substrate having a first type dopant; a buried layer having a second type dopant and formed within the substrate; an epitaxial layer having the second type dopant and formed above the buried layer; and a plurality of regions having the first type dopant within the epitaxial layer. The plurality of regions includes a first region, a second region, and a third region. The diode also includes a base well having the first type dopant and located within the epitaxial layer and in contact with the third and fourth regions. In a reverse-bias mode, the diode is an electrostatic discharge (ESD) clamp and forms parasitic transistors comprising a first bipolar junction transistor (BJT), a second BJT and a third BJT.Type: ApplicationFiled: May 5, 2022Publication date: November 9, 2023Applicant: Allegro MicroSystems, LLCInventors: Sagar Saxena, Washington Lamar, Maxim Klebanov, Chung C. Kuo, Sebastian Courtney, Sundar Chetlur
-
Patent number: 11303116Abstract: An electronic device having first and second terminals includes an electrical overstress (EOS) protection circuitry configured to detect an EOS event at one or both of the first and second terminals. The electronic device includes a power clamp coupled to the EOS protection circuitry and configured to clamp a voltage between the first terminal and the second terminal to a clamp voltage. The EOS protection circuitry can adjust the clamp voltage when an EOS event is detected.Type: GrantFiled: August 29, 2018Date of Patent: April 12, 2022Assignee: Allegro MicroSystems, LLCInventors: Washington Lamar, Maxim Klebanov, Sundar Chetlur
-
Patent number: 11195826Abstract: In one aspect an electronic device includes a substrate having one of a p-type doping or an n-type doping, a first well in the substrate, a second well in the substrate, a third well in the substrate between the first and second wells, a first terminal connected to the first well, a second terminal connected to the second well, an electrostatic discharge (ESD) clamp connected to the first and second terminals and a transient voltage source connected to the third well. A doping type of the first, second and third wells is the other one of the p-type or n-type doping. The ESD clamp is configured to clamp the first and second wells at a clamp voltage during an ESD event and the transient voltage source is configured to provide a voltage during the ESD event that is less than the clamp voltage.Type: GrantFiled: January 30, 2020Date of Patent: December 7, 2021Assignee: Allegro MicroSystems, LLCInventors: Maxim Klebanov, Washington Lamar, Sagar Saxena, Chung C. Kuo, Sebastian Courtney, Sundar Chetlur
-
Publication number: 20210242193Abstract: In one aspect an electronic device includes a substrate having one of a p-type doping or an n-type doping, a first well in the substrate, a second well in the substrate, a third well in the substrate between the first and second wells, a first terminal connected to the first well, a second terminal connected to the second well, an electrostatic discharge (ESD) clamp connected to the first and second terminals and a transient voltage source connected to the third well. A doping type of the first, second and third wells is the other one of the p-type or n-type doping. The ESD clamp is configured to clamp the first and second wells at a clamp voltage during an ESD event and the transient voltage source is configured to provide a voltage during the ESD event that is less than the clamp voltage.Type: ApplicationFiled: January 30, 2020Publication date: August 5, 2021Applicant: Allegro MicroSystems, LLCInventors: Maxim Klebanov, Washington Lamar, Sagar Saxena, Chung C. Kuo, Sebastian Courtney, Sundar Chetlur
-
Patent number: 10943976Abstract: A metal-oxide semiconductor (MOS) transistor structure is provided herein having one or more horizontal and/or one or more vertical MOS transistor structures formed around trench and liner isolation regions. The trench region serves as a gate electrode, while the liner is formed around the sidewalls of trench region and serves as a gate dielectric of a parasitic MOS within the transistor structure. The MOS transistor structure includes various doped regions formed around one or more portions of the trench and liner regions. The doped regions can have one or more different doping types such that in response to a voltage applied to the trench region, a channel region is formed in at least one of the doped regions and provides a current path within the MOS transistor between different doped regions.Type: GrantFiled: August 12, 2019Date of Patent: March 9, 2021Assignee: Allegro MicroSystems, LLCInventors: Sundar Chetlur, Maxim Klebanov, Washington Lamar
-
Patent number: 10649481Abstract: An electronic circuit includes a driver circuit having an output terminal that can be coupled to a load to drive the load. A control circuit is coupled to the driver circuit for controlling the driver circuit. A transistor is coupled in series between the driver circuit and the output terminal. The transistor has a first terminal coupled to the driver circuit and a second terminal coupled to the output terminal. A biasing circuit is coupled to a gate terminal of the transistor and configured to provide a constant voltage to the gate terminal to bias the transistor to a conducting state to reduce the susceptibility of the electronic circuit to electromagnetic interference. The biasing circuit includes a voltage regulator, a Zener diode, and a capacitor. The Zener diode and capacitor are coupled to the gate terminal and a reference terminal.Type: GrantFiled: January 28, 2019Date of Patent: May 12, 2020Assignee: Allegro MicroSystems, LLCInventors: Richard B. Cooper, Maxim Klebanov, Washington Lamar, Devon Fernandez
-
Patent number: 10608430Abstract: An apparatus includes a first terminal, a second terminal, and a conduction path circuit coupled between the first and second terminals. The conduction path circuit includes an input terminal to receive an enable signal which, when activated, allows the conduction path circuit to conduct electrical current between the first and second terminal. A control circuit coupled to the input terminal of the conduction path circuit is configured to selectively activate the enable signal.Type: GrantFiled: September 22, 2016Date of Patent: March 31, 2020Assignee: ALLEGRO MICROSYSTEMS, LLCInventors: Washington Lamar, Maxim Klebanov
-
Publication number: 20200076189Abstract: An electronic device having first and second terminals includes an electrical overstress (EOS) protection circuitry configured to detect an EOS event at one or both of the first and second terminals. The electronic device includes a power clamp coupled to the EOS protection circuitry and configured to clamp a voltage between the first terminal and the second terminal to a clamp voltage. The EOS protection circuitry can adjust the clamp voltage when an EOS event is detected.Type: ApplicationFiled: August 29, 2018Publication date: March 5, 2020Applicant: Allegro MicroSystems, LLCInventors: Washington Lamar, Maxim Klebanov, Sundar Chetlur
-
Publication number: 20190363162Abstract: A metal-oxide semiconductor (MOS) transistor structure is provided herein having one or more horizontal and/or one or more vertical MOS transistor structures formed around trench and liner isolation regions. The trench region serves as a gate electrode, while the liner is formed around the sidewalls of trench region and serves as a gate dielectric of a parasitic MOS within the transistor structure. The MOS transistor structure includes various doped regions formed around one or more portions of the trench and liner regions. The doped regions can have one or more different doping types such that in response to a voltage applied to the trench region, a channel region is formed in at least one of the doped regions and provides a current path within the MOS transistor between different doped regions.Type: ApplicationFiled: August 12, 2019Publication date: November 28, 2019Applicant: Allegro MicroSystems, LLCInventors: Sundar Chetlur, Maxim Klebanov, Washington Lamar
-
Patent number: 10468485Abstract: A metal-oxide semiconductor (MOS) transistor structure is provided herein having one or more horizontal and/or one or more vertical MOS transistor structures formed around trench and liner isolation regions. The trench region serves as a gate electrode, while the liner is formed around the sidewalls of trench region and serves as a gate dielectric of a parasitic MOS within the transistor structure. The MOS transistor structure includes various doped regions formed around one or more portions of the trench and liner regions. The doped regions can have one or more different doping types such that in response to a voltage applied to the trench region, a channel region is formed in at least one of the doped regions and provides a current path within the MOS transistor between different doped regions.Type: GrantFiled: May 26, 2017Date of Patent: November 5, 2019Assignee: Allegro MicroSystems, LLCInventors: Sundar Chetlur, Maxim Klebanov, Washington Lamar
-
Publication number: 20190155322Abstract: An electronic circuit includes a driver circuit having an output terminal that can be coupled to a load to drive the load. A control circuit is coupled to the driver circuit for controlling the driver circuit. A transistor is coupled in series between the driver circuit and the output terminal. The transistor has a first terminal coupled to the driver circuit and a second terminal coupled to the output terminal. A biasing circuit is coupled to a gate terminal of the transistor and configured to provide a constant voltage to the gate terminal to bias the transistor to a conducting state to reduce the susceptibility of the electronic circuit to electromagnetic interference. The biasing circuit includes a voltage regulator, a Zener diode, and a capacitor. The Zener diode and capacitor are coupled to the gate terminal and a reference terminal.Type: ApplicationFiled: January 28, 2019Publication date: May 23, 2019Applicant: Allegro MicroSystems, LLCInventors: Richard B. Cooper, Maxim Klebanov, Washington Lamar, Devon Fernandez
-
Patent number: 10256225Abstract: A gate-less electrostatic discharge (ESD) protection device is provided that can be formed in various complementary metal-oxide-semiconductor (CMOS) systems. The gate-less ESD event protection device includes a substrate, a first doped region formed in the substrate, a second doped region extending into the first doped region, a third doped region extending into the first doped region, a first node formed over a portion of the second doped region and coupled to a source terminal and a second node formed over the third doped region and coupled to a drain terminal. The gate-less ESD protection devices can be formed such that no gate electrode is formed and the gate-less ESD protection device does not include a gate terminal. Thus, an operating voltage range of the gate-less ESD protection device is not limited by gate oxide degradation.Type: GrantFiled: May 22, 2017Date of Patent: April 9, 2019Assignee: Allegro MicroSystems, LLCInventors: Maxim Klebanov, Washington Lamar
-
Patent number: 10234887Abstract: An electronic circuit includes semiconductor substrate having a first doping type and a reference terminal coupled to the semiconductor substrate. A tub area having a second doping type is formed in the semiconductor substrate. A well area having the first doping type is formed within the tub area. A driver circuit comprising a transistor is formed within the well area and has an output terminal. A control circuit is coupled to the driver circuit for controlling the driver circuit. A second transistor is within the well area and coupled in series between the driver circuit and the output terminal, the second transistor having a first terminal coupled to the driver circuit and a second terminal coupled to the output terminal. A biasing circuit is coupled to a gate terminal of the second transistor and configured to bias the transistor to a conducting state.Type: GrantFiled: May 23, 2016Date of Patent: March 19, 2019Assignee: Allegro MicroSystems, LLCInventors: Richard B. Cooper, Maxim Klebanov, Washington Lamar, Devon Fernandez
-
Patent number: 10147688Abstract: An integrated circuit device includes a package and at least two leads exposed external to the package to permit electrical connections to the package. A first die situated in the package has a first substrate and at least a first terminal electrically coupled to a first one of the leads. A second die situated in the package has a second substrate and at least a second terminal electrically coupled to a second one of the lead. An adhesive material holding the first and second die in place forms a voltage-triggered conduction path between the first and second die electrically that isolates the second die from the first die under a first condition and provides an ESD current path between the first one of the leads and the second one of the leads under a second condition.Type: GrantFiled: February 25, 2016Date of Patent: December 4, 2018Assignee: Allegro Microsystems, LLCInventors: William Wilkinson, Washington Lamar, Maxim Klebanov
-
Patent number: 10145904Abstract: An apparatus includes a package, a plurality of external connections extending outside the package, and a first die having a first electrical contact coupled to a first connection of the plurality of external connections. The apparatus also includes a second die having a second electrical contact coupled to a second connection of the plurality of external connections. A conductor is electrically coupled between the first contact and the second contact to allow electrostatic discharge current to flow between the first die to the second die.Type: GrantFiled: August 24, 2016Date of Patent: December 4, 2018Assignee: Allegro MicroSystems, LLCInventors: Maxim Klebanov, Washington Lamar, William P. Taylor
-
Patent number: 10147689Abstract: An electronic device includes a package, a plurality of external leads extending outside the package, a first die within the package having one or more first contacts electrically coupled to at least a first one of the external leads, and a second die within the package having one or more second contacts electrically coupled to at least a second one of the external leads. A capacitive coupling may be positioned between the first and second die to allow electrostatic discharge (ESD) current to flow between the first die and the second die in response to an ESD event and to electrically isolate the first and second die from each other in the absence of the ESD event.Type: GrantFiled: February 28, 2018Date of Patent: December 4, 2018Assignee: Allegro MicroSystems, LLCInventors: Washington Lamar, Maxim Klebanov
-
Publication number: 20180342500Abstract: A metal-oxide semiconductor (MOS) transistor structure is provided herein having one or more horizontal and/or one or more vertical MOS transistor structures formed around trench and liner isolation regions. The trench region serves as a gate electrode, while the liner is formed around the sidewalls of trench region and serves as a gate dielectric of a parasitic MOS within the transistor structure. The MOS transistor structure includes various doped regions formed around one or more portions of the trench and liner regions. The doped regions can have one or more different doping types such that in response to a voltage applied to the trench region, a channel region is formed in at least one of the doped regions and provides a current path within the MOS transistor between different doped regions.Type: ApplicationFiled: May 26, 2017Publication date: November 29, 2018Applicant: Allegro Microsystems, LLCInventors: Sundar Chetlur, Maxim Klebanov, Washington Lamar
-
Publication number: 20180337168Abstract: A gate-less electrostatic discharge (ESD) protection device is provided that can be formed in various complementary metal-oxide-semiconductor (CMOS) systems. The gate-less ESD event protection device includes a substrate, a first doped region formed in the substrate, a second doped region extending into the first doped region, a third doped region extending into the first doped region, a first node formed over a portion of the second doped region and coupled to a source terminal and a second node formed over the third doped region and coupled to a drain terminal. The gate-less ESD protection devices can be formed such that no gate electrode is formed and the gate-less ESD protection device does not include a gate terminal. Thus, an operating voltage range of the gate-less ESD protection device is not limited by gate oxide degradation.Type: ApplicationFiled: May 22, 2017Publication date: November 22, 2018Applicant: Allegro Microsystems, LLCInventors: Maxim Klebanov, Washington Lamar
-
Patent number: 10056364Abstract: An electrical device may include a substrate; a first doped region of the substrate having a p doping type; a second doped region adjacent to the first doped region of the substrate having an n doping type, wherein an interface between the first and second doped regions forms a p-n junction; and a circuit element placed in spaced relation to the p-n junction, the circuit element configured to produce an electric field that interacts with the p-n junction to change a reverse breakdown voltage of the p-n junction. Applicants for the electrical device include ESD protection circuits.Type: GrantFiled: April 7, 2017Date of Patent: August 21, 2018Assignee: Allegro MicroSystems, LLCInventors: Maxim Klebanov, Washington Lamar, Richard B. Cooper, Chung C. Kuo