Patents by Inventor Rajesh Karri

Rajesh Karri 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: 11942866
    Abstract: An error amplifier includes an output pin coupled to a pulse width modulation (PWM) comparator of a buck-boost converter. A first transconductance amplifier adjusts an output current at the output pin and operates in a constant voltage mode. The first transconductance amplifier includes a first positive input to receive a first voltage reference and a first negative input coupled to a tap point of a voltage divider coupled between a voltage bus and a ground of the buck-boost converter. A second transconductance amplifier also adjusts the output current at the output pin and operates in a constant current mode. The second transconductance amplifier includes a second positive input to receive a second voltage reference and a second negative input coupled to a current sense amplifier, the current sense amplifier being coupled to a sense resistor positioned inline along the voltage bus.
    Type: Grant
    Filed: July 21, 2021
    Date of Patent: March 26, 2024
    Assignee: Cypress Semiconductor Corporation
    Inventors: Rajesh Karri, Arun Khamesra
  • Publication number: 20240048053
    Abstract: In an example embodiment, a method comprising identifying, by a primary-side controlled Universal Serial Bus Power Delivery (USB-PD) alternating current to direct current (AC-DC) converter, a first pulse, wherein the first pulse is received from a pulse transformer. The method further includes determining that a threshold duration of time is satisfied. In response to determining that the threshold duration of time is satisfied, the method includes identifying a second pulse, wherein the second pulse is received from the pulse transformer. The first pulse and the second pulse are used for control of a high-side field effect transistor (FET) and a low-side FET, where the high-side FET is coupled to an active clamp flyback (ACF) circuit and the low-side FET is coupled to a flyback transformer of the USB-PD AC-DC converter. In response to identifying the second pulse, the method further includes controlling operation of the high-side FET or the low-side FET.
    Type: Application
    Filed: June 9, 2023
    Publication date: February 8, 2024
    Applicant: Cypress Semiconductor Corporation
    Inventors: Soon Hwei TAN, Rajesh KARRI, Hung-Chun CHEN
  • Patent number: 11870363
    Abstract: A secondary side controller for a flyback converter includes an integrated circuit (IC), which in turn includes: a synchronous rectifier (SR) sense pin coupled to a drain of an SR transistor on a secondary side of the flyback converter; a capacitor having a first side coupled to the SR sense pin, the capacitor to charge or discharge responsive to a voltage sensed at the SR sense pin; a diode-connected transistor coupled between a second side of the capacitor and ground; a first current mirror coupled to the diode-connected transistor and configured to receive, as input current, a reference current from a variable current source; and a peak detect transistor coupled to the diode-connected transistor and to an output of the first current mirror. The peak detect transistor is to output a peak detection signal in response to detecting current from the capacitor drop below the reference current.
    Type: Grant
    Filed: January 14, 2022
    Date of Patent: January 9, 2024
    Assignee: Cypress Semiconductor Corporation
    Inventors: Saravanan Virunjipuram Murugesan, Rajesh Karri, Arun Khamesra, Hariom Rai
  • Publication number: 20230291314
    Abstract: A mode-transition architecture for USB controllers is described herein. In an example embodiment, an integrated circuit (IC) controller includes a controller coupled to a slope compensation circuit, the controller to detect a transition of a buck-boost converter from a first mode having a first duty cycle to a second mode having a second duty cycle that is less or more than the first duty cycle. The controller controls the slope compensation circuit to nullify an error in an output caused by the transition. The controller can cause the slope compensation circuit to apply a charge stored in a capacitor during a first cycle to start a second cycle with a higher voltage than the first cycle.
    Type: Application
    Filed: May 1, 2023
    Publication date: September 14, 2023
    Applicant: Cypress Semiconductor Corporation
    Inventors: Rajesh Karri, Arun Khamesra, Pulkit Shah, Hariom Rai
  • Publication number: 20230231483
    Abstract: A secondary side controller for a flyback converter includes an integrated circuit (IC), which in turn includes: a synchronous rectifier (SR) sense pin coupled to a drain of an SR transistor on a secondary side of the flyback converter; a capacitor having a first side coupled to the SR sense pin, the capacitor to charge or discharge responsive to a voltage sensed at the SR sense pin; a diode-connected transistor coupled between a second side of the capacitor and ground; a first current mirror coupled to the diode-connected transistor and configured to receive, as input current, a reference current from a variable current source; and a peak detect transistor coupled to the diode-connected transistor and to an output of the first current mirror. The peak detect transistor is to output a peak detection signal in response to detecting current from the capacitor drop below the reference current.
    Type: Application
    Filed: January 14, 2022
    Publication date: July 20, 2023
    Applicant: Cypress Semiconductor Corporation
    Inventors: Saravanan VIRUNJIPURAM MURUGESAN, Rajesh KARRI, Arun KHAMESRA, Hariom RAI
  • Patent number: 11671013
    Abstract: An IC controller for USB Type-C device includes an error amplifier (EA), which includes an EA output coupled to a PWM comparator of a buck-boost converter; a first transconductance amplifier to adjust a current at the EA output, the first transconductance amplifier operating in a constant voltage mode; and a second transconductance amplifier to adjust the current at the EA output, the second transconductance amplifier operating in a constant current mode. A first set of programmable registers is to store a first set of increasingly higher transconductance values. A second set of programmable registers is to store a second set of increasingly higher transconductance values. Control logic is to: cause the first transconductance amplifier to operate while sequentially using transconductance values stored in the first set of programmable registers; and cause the second transconductance amplifier to operate while sequentially using transconductance values stored in the second set of programmable registers.
    Type: Grant
    Filed: August 31, 2021
    Date of Patent: June 6, 2023
    Assignee: Cypress Semiconductor Corporation
    Inventors: Arun Khamesra, Hariom Rai, Rajesh Karri, Pulkit Shah
  • Patent number: 11658574
    Abstract: An IC controller for a USB Type-C device includes a register that is programmable to store a pulse width and a frequency. A buck-boost converter of the controller includes a first high-side switch and a second high-side switch. Control logic is coupled to the register and gates of the first/second high-side switches. To perform a soft start in one of buck mode or boost mode, the control logic: causes the second high-side switch to operate in diode mode; retrieves values of the pulse width and the frequency from the register; causes the first high-side switch to turn on using pulses having the pulse width and at the frequency; detects an output voltage at the output terminal of the buck-boost converter that exceeds a threshold value; and in response to the detection, transfers control of the buck-boost converter to an error amplifier loop coupled to the control logic.
    Type: Grant
    Filed: May 6, 2021
    Date of Patent: May 23, 2023
    Assignee: Cypress Semiconductor Corporation
    Inventors: Hariom Rai, Pulkit Shah, Arun Khamesra, Rajesh Karri, Praveen Suresh
  • Patent number: 11658573
    Abstract: A mode-transition architecture for USB controllers is described herein. In an example embodiment, an integrated circuit (IC) controller includes a controller coupled to a slope compensation circuit, the controller to detect a transition of a buck-boost converter from a first mode having a first duty cycle to a second mode having a second duty cycle that is less or more than the first duty cycle. The controller controls the slope compensation circuit to nullify an error in an output caused by the transition. The controller can cause the slope compensation circuit to apply a charge stored in a capacitor during a first cycle to start a second cycle with a higher voltage than the first cycle.
    Type: Grant
    Filed: January 13, 2021
    Date of Patent: May 23, 2023
    Assignee: Cypress Semiconductor Corporation
    Inventors: Rajesh Karri, Arun Khamesra, Pulkit Shah, Hariom Rai
  • Patent number: 11606042
    Abstract: A secondary side controller of a flyback AC-DC converter includes an integrated circuit, which includes: an analog-to-digital converter (ADC) coupled to a voltage bus (VBUS), the ADC to output a digital value corresponding to a voltage level of the VBUS; first logic configured to generate a reference voltage based on the digital value; second logic configured to generate a VBUS gain value based on output power of a flyback transformer of the flyback AC-DC converter; an integrator to accumulate current corresponding to a sensed voltage at a drain of a synchronous rectifier (SR) of a secondary side of the flyback transformer, the accumulated current to be modified according to the VBUS gain value, wherein the integrator outputs an updated sensed voltage; and a comparator to output a detection signal, indicative of a negative sense voltage, in response to the updated sensed voltage matching the reference voltage.
    Type: Grant
    Filed: January 14, 2022
    Date of Patent: March 14, 2023
    Assignee: Cypress Semiconductor Corporation
    Inventors: Partha Mondal, Rajesh Karri, Hariom Rai
  • Patent number: 11527957
    Abstract: A mode-transition architecture for USB Type-C controllers is described herein. In an example embodiment, an integrated circuit (IC) controller includes controller includes a controller coupled to a slope compensation circuit, the controller to cause the slope compensation circuit to apply a first slope compensation to the input current in a first mode in which the buck-boost converter is operating in a discontinuous conduction mode (DCM). The controller detects a transition of the buck-boost converter from a first mode having a first duty cycle to a second mode and causes the slope compensation circuit to apply a second slope compensation to the input current. The second slope compensation starts at a maximum offset of the first slope compensation.
    Type: Grant
    Filed: January 13, 2021
    Date of Patent: December 13, 2022
    Assignee: Cypress Semiconductor Corporation
    Inventors: Rajesh Karri, Arun Khamesra, Pulkit Shah, Hariom Rai
  • Publication number: 20220069713
    Abstract: An IC controller for USB Type-C device includes an error amplifier (EA), which includes an EA output coupled to a PWM comparator of a buck-boost converter; a first transconductance amplifier to adjust a current at the EA output, the first transconductance amplifier operating in a constant voltage mode; and a second transconductance amplifier to adjust the current at the EA output, the second transconductance amplifier operating in a constant current mode. A first set of programmable registers is to store a first set of increasingly higher transconductance values. A second set of programmable registers is to store a second set of increasingly higher transconductance values. Control logic is to: cause the first transconductance amplifier to operate while sequentially using transconductance values stored in the first set of programmable registers; and cause the second transconductance amplifier to operate while sequentially using transconductance values stored in the second set of programmable registers.
    Type: Application
    Filed: August 31, 2021
    Publication date: March 3, 2022
    Applicant: Cypress Semiconductor Corporation
    Inventors: Arun Khamesra, Hariom Rai, Rajesh Karri, Pulkit Shah
  • Publication number: 20220069711
    Abstract: An error amplifier includes an output pin coupled to a pulse width modulation (PWM) comparator of a buck-boost converter. A first transconductance amplifier adjusts an output current at the output pin and operates in a constant voltage mode. The first transconductance amplifier includes a first positive input to receive a first voltage reference and a first negative input coupled to a tap point of a voltage divider coupled between a voltage bus and a ground of the buck-boost converter. A second transconductance amplifier also adjusts the output current at the output pin and operates in a constant current mode. The second transconductance amplifier includes a second positive input to receive a second voltage reference and a second negative input coupled to a current sense amplifier, the current sense amplifier being coupled to a sense resistor positioned inline along the voltage bus.
    Type: Application
    Filed: July 21, 2021
    Publication date: March 3, 2022
    Applicant: Cypress Semiconductor Corporation
    Inventors: Rajesh Karri, Arun Khamesra
  • Publication number: 20220069562
    Abstract: A Universal Serial Bus controller including a Vconn switch having a current controlled architecture, and method for operating the same are provided. Generally, the Vconn switch includes first and second transistors coupled in series between a Vconn terminal and a communication channel (CC) terminal, a replica switch including a source coupled to the Vconn terminal, a replica current generator including a first input coupled to a drain of the replica switch and a second input coupled to a drain of the first transistor, and a resistance control module coupled to an output of the replica current generator and including an output coupled to a gate of the second transistor. The replica current generator is operable to match a current through the replica switch to that supplied through the first and second transistors to the CC terminal, and the resistance control module is operable to control resistance of the Vconn switch.
    Type: Application
    Filed: May 20, 2021
    Publication date: March 3, 2022
    Applicant: Infineon Technologies LLC
    Inventors: Rajesh Karri, Arun Khamesra
  • Publication number: 20220069715
    Abstract: A mode-transition architecture for USB Type-C controllers is described herein. In an example embodiment, an integrated circuit (IC) controller includes controller includes a controller coupled to a slope compensation circuit, the controller to cause the slope compensation circuit to apply a first slope compensation to the input current in a first mode in which the buck-boost converter is operating in a discontinuous conduction mode (DCM). The controller detects a transition of the buck-boost converter from a first mode having a first duty cycle to a second mode and causes the slope compensation circuit to apply a second slope compensation to the input current. The second slope compensation starts at a maximum offset of the first slope compensation.
    Type: Application
    Filed: January 13, 2021
    Publication date: March 3, 2022
    Applicant: Cypress Semiconductor Corporation
    Inventors: Rajesh Karri, Arun Khamesra, Pulkit Shah, Hariom Rai
  • Publication number: 20220069708
    Abstract: A mode-transition architecture for USB controllers is described herein. In an example embodiment, an integrated circuit (IC) controller includes a controller coupled to a slope compensation circuit, the controller to detect a transition of a buck-boost converter from a first mode having a first duty cycle to a second mode having a second duty cycle that is less or more than the first duty cycle. The controller controls the slope compensation circuit to nullify an error in an output caused by the transition. The controller can cause the slope compensation circuit to apply a charge stored in a capacitor during a first cycle to start a second cycle with a higher voltage than the first cycle.
    Type: Application
    Filed: January 13, 2021
    Publication date: March 3, 2022
    Applicant: Cypress Semiconductor Corporation
    Inventors: Rajesh Karri, Arun Khamesra, Pulkit Shah, Hariom Rai