Abstract: An integrated circuit package includes a portion of a lead frame disposed within an encapsulation. The lead frame includes a first conductor including a first conductive loop and a third conductive loop disposed substantially within the encapsulation. A second conductor formed in the lead frame is galvanically isolated from the first conductor and includes a second conductive loop disposed substantially within the encapsulation proximate to the first conductive loop to provide a communication link between the first and second conductors. The third conductive loop is wound in an opposite direction relative to the first conductive loop. A transmit circuit is disposed within the encapsulation and is coupled to the second conductor to provide a transmitter current. A receive circuit is disposed within the encapsulation and is coupled to the first conductor to receive a transmitter induced signal in response to the transmitter current.

Abstract: An ac-dc power supply includes a dc-dc converter coupled to an input of the ac-dc power supply. The input of the ac-dc power supply is coupled to receive an ac input voltage and an ac input current. The dc-dc converter includes a regulated output and a reservoir output. A controller is coupled to receive sense signals from the dc-dc converter. The controller is coupled to control the dc-dc converter to regulate the regulated output in response to the sense signals. The controller is further coupled to control a waveform of the ac input current to have a substantially same shape as a waveform of the ac input voltage. A regulator circuit is coupled to the regulated output and the reservoir output. The controller is coupled to the regulator circuit to control a transfer of energy from the reservoir output to the regulated output through the regulator circuit.

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 for receiving an enable signal including enable events is 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 enable events and vary the current limit threshold in response to the enable events of the enable signal.

Abstract: An integrated circuit package includes an encapsulation and a lead frame with a portion of the lead frame disposed within the encapsulation. The lead frame includes first and second conductive loops. A first voltage is induced between first and second ends of the first conductive loop in response to an external magnetic field that passes through the integrated circuit package. A second voltage is induced between third and fourth ends of the second conductive loop of the lead frame in response to the external magnetic field that passes through the integrated circuit package. The first conductive loop is coupled to the second conductive loop such that the first voltage between the first and second ends combined with the second voltage between the third and fourth ends substantially cancel.

Abstract: A power converter controller includes a primary controller configured to operate in a first mode to control a power switch with a primary switching pattern. A communication link is coupled to the primary controller. A secondary controller coupled to the communication link. The secondary controller is galvanically isolated from the primary controller. The secondary controller is configured to initiate a transition operation with the primary controller to take control of the power switch with one or more control signals through the communication link. The primary controller is configured to acknowledge receipt of the one or more control signals through the communication link to the secondary controller and transition from the first mode to a second mode.

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 includes an energy transfer element and a circuit coupled to the input of the power converter. The circuit includes a switch and a control circuit capable of detecting whether an AC voltage source is coupled to the input, or uncoupled from the input within a first predetermined time. The control circuit is coupled to drive the switch in a first operating mode when the AC voltage source is coupled, drive the switch in a second operating mode when the AC voltage source is uncoupled, and is capable of discharging a capacitance coupled between input terminals of the power converter to a threshold voltage level through a discharge path and through the switch within a second predetermined time. An RC time constant of the discharge path is less than or equal to one second and the threshold voltage level is less than or equal to ten volts.

Abstract: A power converter controller includes a primary controller coupled to operate in a first mode to control a power switch with a primary switching pattern. A secondary controller is galvanically isolated from the primary controller. The secondary controller is coupled to initiate a transition operation with the primary controller to take control of the power switch with one or more control signals through a communication link. The primary controller is coupled to acknowledge receipt of the one or more control signals to the secondary controller and transition from the first mode to a second mode.

Abstract: A control circuit for use in an isolated power converter includes an output-side first controller having a switch control signal generator and an extremum locator. The switch control signal generator communicates a control signal to a second controller on the input side of the power converter via an isolated interface to initiate a transition of a switch from an OFF state to an ON state. The extremum locator enables the switch control signal generator to communicate the control signal in response to an oscillating voltage signal at an output terminal of the energy transfer element. The extremum locator enables the switch control signal generator such that the transition of the switch from the OFF state to the ON state occurs substantially at a time that the oscillating voltage signal reaches an extremum.

Abstract: A circuit for use in a power converter includes a control circuit coupled to detect whether an electrical energy source is coupled to an input of the power converter. A switch is coupled to the control circuit, and is coupled to transfer energy from the input of the power converter to an output of the power converter during a first operating mode. The control circuit is coupled to drive the switch in the first operating mode when the electrical energy source is coupled to the input of the power converter. The control circuit is coupled to drive the switch in a second operating mode when the electrical energy source is uncoupled from the input of the power converter to drive the switch to discharge a capacitance coupled between input terminals of the power converter to a threshold voltage in less than a maximum period of time.

Abstract: A secondary control circuit includes a voltage regulator circuit coupled to an output of the power converter to provide a regulated power supply. One or more switched loads are coupled between a first terminal and an output ground terminal. The first terminal is coupled to the output of the power converter. Each switched load is coupled to draw a respective current from a load current to clamp the output of a power converter. One or more comparator circuits are coupled to a second terminal. The second terminal is coupled to receive an output sense signal. Each comparator circuit is coupled to receive a reference signal that is a scaled representation of a first reference signal. Each switched load is switched in response to a respective comparator circuit to draw a respective current from the load current of the power converter to clamp the output of the power converter.

Abstract: A method for regulating an output of a power converter includes receiving a signal at a single terminal of an integrated circuit controller. The signal at the single terminal represents a line input voltage of the power converter during at least a portion of an on time of a power switch. The signal at the single terminal represents an output voltage of the power converter during at least a portion of an off time of the power switch. The power switch is switched in response to the signal to regulate the output of the power converter.

Abstract: A controller includes a switching control coupled to switch a power switch of a power converter to regulate an output of the power converter. A sensor is coupled to receive a signal from a single terminal of the controller. The signal from the single terminal is representative of a line input voltage of the power converter during at least a portion of an on time of the power switch, and an output voltage of the power converter during at least a portion of an off time of the power switch. The switching control is responsive to an output of the sensor, and includes a first current source, an internal voltage supply coupled to the first current source, and a buffer circuit coupled to receive the signal from the single terminal. The first current source is coupled to supply a first current to the buffer circuit.

Abstract: An apparatus includes an ON/OFF controller for regulating an output of a switched mode power supply by selectively enabling current conduction by a power switch within enabled switching cycles and disabling current conduction by the power switch within disabled switching cycles. The controller includes a logic block and a time-to-frequency converter. The logic block generates a drive signal that enables the current conduction by the power switch within respective enabled switching cycles and disables the current conduction by the power switch within respective disabled switching cycles. The time-to-frequency converter generates a variable-frequency clock signal that defines durations of the switching cycles, where the time-to-frequency converter increases a duration of a switching cycle in response to a decrease in duration of current conduction by the power switch in a previously enabled switching cycle.

Abstract: A controller includes a primary controller and a secondary controller to control switching of a power switch and a secondary switch, respectively, coupled to an energy transfer element of a power converter. A first drive circuit is coupled to generate a first drive signal to enable a first ON section of the secondary drive signal after an ON section of the primary drive signal. A second drive circuit is coupled to generate a second drive signal to enable a second ON section of the secondary drive signal to store energy in the energy transfer element. The energy stored in the energy transfer element during the second ON section is coupled to reduce a switch voltage across the power switch prior to a next ON section of the primary drive signal. The secondary drive signal is generated in response to the first drive signal and the second drive signal.

Abstract: An integrated circuit package includes an encapsulation and a lead frame with a portion of the lead frame disposed within the encapsulation. The lead frame includes first and second conductive loops. A first voltage is induced between first and second ends of the first conductive loop in response to an external magnetic field that passes through the integrated circuit package. A second voltage is induced between third and fourth ends of the second conductive loop of the lead frame in response to the external magnetic field that passes through the integrated circuit package. The first conductive loop is coupled to the second conductive loop such that the first voltage between the first and second ends combined with the second voltage between the third and fourth ends substantially cancel.

Abstract: An integrated circuit package includes an electromagnetic communication link formed by a portion of a lead frame within an encapsulation. The lead frame includes a first conductor forming a first conductive loop a second conductor forming a second conductive loop galvanically isolated from the first conductive loop. The second conductive loop is magnetically coupled to the first conductive loop to provide a magnetic communication link between the first and second conductors. A first transceiver circuit includes a transmit circuit coupled to the first conductive loop. A second transceiver circuit includes a receive circuit coupled to the second conductive loop. A signal transmitted from the transmit circuit included in first transceiver circuit and coupled to the first conductor is coupled to be magnetically communicated through the magnetic communication link to the receive circuit included in second transceiver circuit and coupled to the second conductor.

Abstract: An integrated circuit (IC) comprises a rectifier/regulator circuit coupled to receive an ac source voltage and output a regulated dc voltage. The rectifier/regulator circuit includes first and second switching elements that provide charging current when enabled. The first and second switching elements do not provide charging current when disabled. A sensor circuit is coupled to sense the regulated dc voltage and generate a feedback control signal coupled to the rectifier/regulator circuit that enables the first and second switching elements when the regulated do voltage is above a target voltage, and disables the first and second switching elements when the regulated do voltage is below the target voltage.

Abstract: An integrated circuit package includes an encapsulation and a lead frame with a portion of the lead frame disposed within the encapsulation. The lead frame includes a first conductor having a first conductive loop and a third conductive loop disposed within the encapsulation. The third conductive loop is wound in a direction relative to the first conductive loop such that the first conductive loop is coupled out of phase with the third conductive loop. The lead frame also includes a second conductor galvanically isolated from the first conductor. The second conductor includes a second conductive loop disposed within the encapsulation proximate to the first conductive loop to provide a communication link between the first and second conductors.

Abstract: An integrated circuit package includes an encapsulation and a lead frame. A portion of the lead frame is disposed within the encapsulation. The lead frame includes a first conductor forming a first conductive loop. A second conductor is galvanically isolated from the first conductor. The second conductor forms a second conductive loop proximate to and magnetically coupled to the first conductive loop to provide a magnetic communication link between the first and second conductors. A signal that is transmitted from a transmit circuit coupled to the first conductor is coupled to be received through the magnetic communication link by a receive circuit coupled to the second conductor.