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 having an inner conductive loop disposed substantially within the encapsulation and a second conductor galvanically isolated from the first conductor. The second conductor includes an outer conductive loop disposed substantially within the encapsulation proximate to and magnetically coupled to the inner conductive loop to provide a communication link between the first and second conductors.

Abstract: A controller includes a switch controller, a current limit generator, a jitter modulator, and an arithmetic operator circuit. The switch controller is coupled to generate a drive signal to control switching of a power switch in response to a current sense signal and a modulated current limit signal to control a transfer of energy from an input of a power converter to an output of the power converter. The current limit generator is coupled to generate a current limit signal. The jitter modulator is coupled to generate a jitter signal for jittering a switching period of the drive signal without an oscillator. The arithmetic operator circuit is coupled to receive the current limit signal and the jitter signal and is coupled to generate a modulated current limit signal in response to the current limit signal and the jitter signal.

Abstract: A circuit for use in a power converter includes a control circuit capable of detecting whether an AC voltage source is coupled to an input of the power converter, and whether the AC voltage source is uncoupled from the input within a first period of time. A control circuit is coupled to drive a switch in a first operating mode when the control circuit detects that the AC voltage source is coupled to the input, and drive the switch in a second operating mode when the control circuit detects that the AC voltage source is uncoupled from the input. The control circuit is capable of discharging a capacitance coupled between input terminals of the power converter to a SELV level through a discharge path and the switch within a second period of time. An RC time constant of the discharge path is less than or equal to one second.

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: A controller includes a switch controller coupled to a power switch coupled to an energy transfer element. The switch controller is coupled to receive a current sense signal representative of a drain current through the power switch. The switch controller is coupled to generate a drive signal to control switching of the power switch in response to the current sense signal and a modulated current limit signal to control a transfer of energy from an input to an output of the power converter. A control modulator is coupled to generate a first signal. A jitter modulator is coupled to generate a second signal. The second signal is a periodic signal having a modulation time period that is greater than a switching period of the drive signal. An arithmetic operator circuit is coupled to generate the modulated current limit signal in response to the first signal and the second 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 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 controller for use in a power converter includes a power switch including a drain, a source, a control input, and a tap. The power switch includes a first transistor coupled to a second transistor, a drain of the first transistor is coupled to the drain of the power switch and the source of the first transistor is coupled to the tap. A tap sense circuit is coupled to the tap. A drive circuit is coupled to receive an indicator signal from the tap sense circuit. The indicator signal is indicative of a voltage at the tap or the current through the first transistor. The drive circuit is coupled to receive a feedback signal representative of an output quantity of the power converter. The drive circuit is coupled to generate a drive signal to control switching of the power switch in response to the indicator signal and the feedback signal.

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: 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 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 having an inner conductive loop disposed substantially within the encapsulation and a second conductor galvanically isolated from the first conductor. The second conductor includes an outer conductive loop disposed substantially within the encapsulation proximate to and magnetically coupled to the inner conductive loop to provide a communication link between the first and second conductors.

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 power converter controller includes a primary controller and a secondary controller. The primary controller is coupled to receive one or more request signals from the secondary controller and transition a power switch from an OFF state to an ON state in response to the received request signals. The secondary controller is coupled to transmit the request signals to the primary controller and control the amount of time between the transmission of each of the request signals. The secondary controller includes a timing circuit that sets a minimum amount of time between the transmission of the request signals. The secondary controller also includes a secondary switch control circuit coupled to trigger the timing circuit in response to transmitting a request signal.

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: A controller includes a switch controller coupled to a power switch coupled to an energy transfer element. The switch controller is coupled to receive a current sense signal representative of a drain current through the power switch. The switch controller is coupled to generate a drive signal to control switching of the power switch in response to the current sense signal and a modulated current limit signal to control a transfer of energy from an input to an output of the power converter. A control modulator is coupled to generate a first signal. A jitter modulator is coupled to generate a second signal. The second signal is a periodic signal having a modulation time period that is greater than a switching period of the drive signal. An arithmetic operator circuit is coupled to generate the modulated current limit signal in response to the first signal and the second signal.

Abstract: A method of operating a power converter includes applying a first signal sequence to one or more terminals of the power converter to unlock a controller of the power converter and cause the controller to enter a programming mode, applying a second signal sequence to the one or more terminals of the power converter to program a controller parameter of the power converter, and applying a third signal sequence to the one or more terminals to lock the controller of the power converter and cause the power converter to enter a locked mode. The one or more terminals of the power converter includes one or more input terminals of the power converter that converter are adapted to be coupled to a programmable ac or dc supply, or one or more output terminals of the power converter that are adapted to be coupled to a programmable electronic load.

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: 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 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.