Abstract: A power converter includes a damping circuit coupled to the dissipative element for dissipating energy corresponding to a resonant ringing produced by a magnetic inductance of the energy transfer element and by the switch capacitance when the power converter is in discontinuous conduction mode.

Abstract: A control circuit comprising an output controller coupled to an output side of a power converter. The output controller comprises a switch control signal generator to receive a feedback signal representative of an output of the power controller and to communicate a control signal to an input controller coupled to an input side to control a turn ON of a power switch. The control signal is generated in response to the feedback signal and is communicated in response to an enable signal. The output controller comprises an extremum locator to generate the enable signal in response to a winding signal representative of an instantaneous voltage on an output terminal of an energy transfer element and the extremum locator enables the switch control signal generator such that the transition of the power switch from the OFF state to the ON state occurs substantially when the winding signal reaches an extremum.

Abstract: A switched mode power converter has an energy transfer element that delivers an output signal to a load. A power switching device coupled to the primary side of the energy transfer element regulates a transfer of energy to the load. A secondary controller is coupled to receive a feedback signal and output a pulsed signal in response thereto. A primary controller is coupled to receive the pulsed signal and output a drive signal in response thereto, the drive signal being coupled to control switching of the power switching device. A compensation circuit generates an adaptively compensated signal synchronous with the pulsed signal. The adaptively compensated signal has a parameter that is adaptively adjusted in response to a comparison of the feedback signal with a threshold reference signal. The parameter converges towards a final value that produces a desired level of the output signal.

Abstract: A controller for use in a power converter for transferring energy between an input and an output, the controller comprising a second controller to generate a request event and a request signal in response to a feedback signal and a switching window signal, the second controller to transmit the request event during a switching window of the switching window signal. The second controller comprising an extremum locator switching window generator to generate the switching window corresponding with an extremum in the winding signal and a measurement enable circuit to output an enable signal to enable the extremum locator switching window generator to measure a duration of a half cycle to generate the switching window. The measurement enable circuit to enable the extremum locator switching window generator in response to the feedback signal reaching a percentage of a target reference and output a quiet signal to prevent transmitting the request event.

Abstract: A control circuit comprising an output controller coupled to an output side of a power converter. The output controller comprises a switch control signal generator to receive a feedback signal representative of an output of the power controller and to communicate a control signal to an input controller coupled to an input side to control a turn ON of a power switch. The control signal is generated in response to the feedback signal and is communicated in response to an enable signal. The output controller comprises an extremum locator to generate the enable signal in response to a winding signal representative of an instantaneous voltage on an output terminal of an energy transfer element and the extremum locator enables the switch control signal generator such that the transition of the power switch from the OFF state to the ON state occurs substantially when the winding signal reaches an extremum.

Abstract: A method of providing an input switching request signal to an input side switch includes determining a switching request window indicative of relaxation ringing during a first switching cycle. It is determined that the input side switch is operating in a discontinuous conduction mode (DCM) mode of operation during a second switching cycle. It is determined that the switching request window is open during the second switching cycle. The input switching request signal is enabled in response to determining the switching request window is open.

Abstract: A controller for use in a power converter for transferring energy between an input and an output, the controller comprising a second controller to generate a request event and a request signal in response to a feedback signal and a switching window signal, the second controller to transmit the request event during a switching window of the switching window signal. The second controller comprising an extremum locator switching window generator to generate the switching window corresponding with an extremum in the winding signal and a measurement enable circuit to output an enable signal to enable the extremum locator switching window generator to measure a duration of a half cycle to generate the switching window. The measurement enable circuit to enable the extremum locator switching window generator in response to the feedback signal reaching a percentage of a target reference and output a quiet signal to prevent transmitting the request event.

Abstract: A switched mode power converter has an energy transfer element that delivers an output signal to a load. A power switching device coupled to the primary side of the energy transfer element regulates a transfer of energy to the load. A secondary controller is coupled to receive a feedback signal and output a pulsed signal in response thereto. A primary controller is coupled to receive the pulsed signal and output a drive signal in response thereto, the drive signal being coupled to control switching of the power switching device. A compensation circuit generates an adaptively compensated signal synchronous with the pulsed signal. The adaptively compensated signal has a parameter that is adaptively adjusted in response to a comparison of the feedback signal with a threshold reference signal. The parameter converges towards a final value that produces a desired level of the output signal.

Abstract: A switched mode power converter has an energy transfer element that delivers an output signal to a load. A power switching device coupled to the primary side of the energy transfer element regulates a transfer of energy to the load. A secondary controller is coupled to receive a feedback signal and output a pulsed signal in response thereto. A primary controller is coupled to receive the pulsed signal and output a drive signal in response thereto, the drive signal being coupled to control switching of the power switching device. A compensation circuit generates an adaptively compensated signal synchronous with the pulsed signal. The adaptively compensated signal has a parameter that is adaptively adjusted in response to a comparison of the feedback signal with a threshold reference signal. The parameter converges towards a final value that produces a desired level of the output signal.

Abstract: A controller for use in a power converter includes a drive circuit coupled to generate a drive signal to control switching of a power switch to control a transfer of energy from a power converter input to a power converter output. An input is also included to receive an enable signal including enable events responsive to the power converter output. The drive circuit is coupled to turn ON the power switch in response to the enable events, and turn OFF the power switch in response to a power switch current reaching a current limit threshold. A current limit threshold generator is coupled to receive the drive signal from the drive circuit to vary the current limit threshold at a variable rate in response to the enable events of the enable signal.

Abstract: A method of providing an input switching request signal to an input side switch includes determining a switching request window indicative of relaxation ringing during a first switching cycle. It is determined that the input side switch is operating in a discontinuous conduction mode (DCM) mode of operation during a second switching cycle. It is determined that the switching request window is open during the second switching cycle. The input switching request signal is enabled in response to determining the switching request window is open.

Abstract: A power converter controller includes a drive circuit to generate a drive signal to control switching of a power switch. The drive circuit generates the drive signal in response to a current sense signal, a current limit signal, a frequency skip signal, and a hold signal. A current limit generator generates the current limit signal in response to a load. A frequency detection circuit generates the frequency skip signal in response to the drive signal to indicate when an intended frequency of the drive signal is within a frequency window. The current limit signal remains fixed for at least a switching cycle when the intended frequency is within the frequency window. A first latch generates the hold signal to control the current limit generator to hold the current limit signal. The first latch generates the hold signal in response to the frequency skip signal and a feedback signal.

Abstract: A circuit for use with a Universal Serial Bus (USB) socket includes a power converter coupled to receive an input voltage at an input terminal and coupled to provide an output voltage at an output terminal. A transistor is coupled between the output terminal of the power converter and a bus voltage terminal of the USB socket. A USB communication controller is coupled to the USB socket. The USB communication controller includes an output terminal coupled to a control terminal of the transistor. A bleeder circuit is coupled between the output terminal of the USB communication controller and the bus voltage terminal of the USB socket.

Abstract: A method for regulating a power converter includes initiating a transition of a switch coupled to an input side of the power converter from an OFF to an ON state to regulate a transfer of energy from the input to an output side of the power converter after a switch control signal generator receives an enable signal and if a feedback signal representative of an output of the power converter indicates a change in an output of the power converter. The enable signal is generated to communicate a control signal from the output to the input side in response to a first signal representative of a voltage on an output terminal that oscillates in response to an ending of the transfer of energy. The transition of the switch from the OFF to the ON state occurs substantially at a time that the first signal reaches an extremum.

Abstract: A power converter controller includes a drive circuit to generate a drive signal to control switching of a power switch. The drive circuit generates the drive signal in response to a current sense signal, a current limit signal, a frequency skip signal, and a hold signal. A current limit generator generates the current limit signal in response to a load. A frequency detection circuit generates the frequency skip signal in response to the drive signal to indicate when an intended frequency of the drive signal is within a frequency window. The current limit signal remains fixed for at least a switching cycle when the intended frequency is within the frequency window. A first latch generates the hold signal to control the current limit generator to hold the current limit signal. The first latch generates the hold signal in response to the frequency skip signal and a feedback signal.

Abstract: A switched mode power converter has an energy transfer element that delivers an output signal to a load. A power switching device coupled to the primary side of the energy transfer element regulates a transfer of energy to the load. A secondary controller is coupled to receive a feedback signal and output a pulsed signal in response thereto. A primary controller is coupled to receive the pulsed signal and output a drive signal in response thereto, the drive signal being coupled to control switching of the power switching device. A compensation circuit generates an adaptively compensated signal synchronous with the pulsed signal. The adaptively compensated signal has a parameter that is adaptively adjusted in response to a comparison of the feedback signal with a threshold reference signal. The parameter converges towards a final value that produces a desired level of the output signal.

Abstract: A circuit for use with a Universal Serial Bus (USB) socket includes a power converter coupled to receive an input voltage at an input terminal and coupled to provide an output voltage at an output terminal. A transistor is coupled between the output terminal of the power converter and a bus voltage terminal of the USB socket. A USB communication controller is coupled to the USB socket. The USB communication controller includes an output terminal coupled to a control terminal of the transistor. A bleeder circuit is coupled between the output terminal of the USB communication controller and the bus voltage terminal of the USB socket.

Abstract: A controller includes a drive circuit that generates a drive signal to switch a power switch to control a transfer of energy to of a power converter output in response to a current sense signal, a feedback signal, and a current limit signal. A current limit generator generates the current limit signal in response to a load coupled to the output. An exclusion frequency range detection circuit generates a frequency skip signal in response to the drive signal to indicate when an intended frequency of the drive signal is within an exclusion frequency window. The current limit signal is unvarying for at least a switching cycle when the intended frequency of the drive signal is within the exclusion frequency window. A first latch generates a hold signal to control the current limit generator to hold the current limit signal in response to the frequency skip signal and the feedback signal.

Abstract: A controller includes a drive circuit that generates a drive signal to switch a power switch to control a transfer of energy to of a power converter output in response to a current sense signal, a feedback signal, and a current limit signal. A current limit generator generates the current limit signal in response to a load coupled to the output. An exclusion frequency range detection circuit generates a frequency skip signal in response to the drive signal to indicate when an intended frequency of the drive signal is within an exclusion frequency window. The current limit signal is unvarying for at least a switching cycle when the intended frequency of the drive signal is within the exclusion frequency window. A first latch generates a hold signal to control the current limit generator to hold the current limit signal in response to the frequency skip signal and the feedback signal.

Abstract: A controller for use in a power converter includes a drive circuit coupled to generate a drive signal to control switching of a power switch to control a transfer of energy from a power converter input to a power converter output. An input is also included to receive an enable signal including enable events responsive to the power converter output. The drive circuit is coupled to turn ON the power switch in response to the enable events, and turn OFF the power switch in response to a power switch current reaching a current limit threshold. A current limit threshold generator is coupled to receive the drive signal from the drive circuit to vary the current limit threshold at a variable rate in response to the enable events of the enable signal.