Abstract: A voltage sense circuit and power supply regulation technique. In one aspect, a voltage sense circuit utilized in a power supply regulator includes a transformer including a sense winding and an output winding. A first diode is coupled to the sense winding, a first resistor is coupled to the first diode and a first capacitor coupled to the first resistor and the first diode. A second diode coupled to the first capacitor, the first resistor and the first diode. A second capacitor coupled to the second diode such that a voltage across the second capacitor is representative of a voltage across the output winding. In one embodiment, the first capacitor is discharged in a substantially shorter period of time than the second capacitor such that the second capacitor is charged substantially without influence from leakage inductance energy from the transformer.

Abstract: Techniques are disclosed to extend an on time period of switch to regulate a transfer of energy from an input of a power supply to an output of a power supply. One example integrated circuit includes an energy transfer element coupled between an input and an output of the power supply. A switch is coupled to the input of the energy transfer element. A controller is coupled to the switch to control switching of the switch to regulate a transfer of energy from the input of the power supply to the output of the power supply in response to a feedback signal received from the output of the power supply. The controller is coupled to limit a maximum on time period of the switch a first maximum on time period in response to a first range of power supply operating conditions and to a second maximum on time period for a second range of power supply operating conditions.

Abstract: A power converter control method and apparatus is disclosed. A control circuit for use in a power converter according to aspects of the present invention includes a clock signal generator coupled to generate a clock signal to control switching of a power switch to be coupled to the control circuit. Feedback circuitry is coupled to receive a feedback signal, which is representative of an output of a power converter during a feedback portion of an off time of the power switch. The feedback circuitry is coupled to respond to the feedback signal to control the clock signal generator to regulate a duty cycle of the feedback portion of the off time of the power switch as a proportion of a total power switch switching cycle period.

Abstract: A control circuit for use in a power supply is disclosed. An example control circuit according to aspects of the present invention includes a signal generator coupled to generate an output signal to control switching of a power switch to be coupled to the control circuit. A feedback circuit is coupled to receive a feedback signal, which is representative of an output of the power supply during a feedback portion of an off time of the power switch. The signal generator generates the output signal in response to the feedback circuit to control a fraction of the feedback portion of the off time of the power switch that the feedback signal is above a threshold and another fraction of the feedback portion of the off time of the power switch that the feedback signal is below the threshold.

Abstract: Techniques are disclosed to extend an on time period of switch to regulate a transfer of energy from an input of a power supply to an output of a power supply. One example integrated circuit includes an energy transfer element coupled between an input and an output of the power supply. A switch is coupled to the input of the energy transfer element. A controller is coupled to the switch to control switching of the switch to regulate a transfer of energy from the input of the power supply to the output of the power supply in response to a feedback signal received from the output of the power supply. The controller is coupled to limit a maximum on time period of the switch a first maximum on time period in response to a first range of power supply operating conditions and to a second maximum on time period for a second range of power supply operating conditions.

Abstract: Techniques are disclosed to control a current through a load to be coupled to an output of a power converter. In one aspect, a power converter includes an energy transfer element coupled between an input of the power converter and an output of the power converter. A power converter controller is coupled to the energy transfer element to control a transfer of energy from an input of the power converter to the output of the power converter. A current source is coupled to the output of the power converter. A switch is coupled to the current source and is coupled to be switched on and off at a duty cycle to control an average current in a load to be coupled to the output of the power converter.

Abstract: Techniques are disclosed to regulate an output current through a load coupled to a power converter using a current source coupled to the load. For instance, one power converter according to the teachings of the present invention includes an energy transfer element coupled between an input of the power converter and an output of the power converter. The power converter also includes a controller circuit coupled to the energy transfer element and the input of the power converter to regulate the output of the power converter. A current source circuit is also included and is coupled to the output of the power converter to limit an output current of the power converter to below a threshold value.

Abstract: Techniques are disclosed to regulate a power supply with a compensation signal generation circuit. One example regulated power supply includes a sense circuit coupled to sense an output voltage of the regulated power supply. The regulated power supply also includes a switching power converter circuit, which includes a switch coupled to be switched in response to a control signal received from the sense circuit to regulate the output voltage of the regulated power supply. The regulated power supply also includes a compensation signal generation circuit coupled to receive a switching signal representative of a switching of the switch in the switching power converter circuit. The compensation signal generation circuit is to generate a compensation signal to approximate a load current to be delivered from an output of the regulated power supply. The compensation signal is to be received by the sense circuit to modify the control signal.

Abstract: Apparatus for reducing electrical earth displacement current flow generated by wound components is disclosed. In one aspect, an apparatus includes a plurality of layers of an input winding wound around an energy transfer element core. An outer layer of the plurality of layers of the input winding is wound with a number of turns different than the number of turns in substantially each of the inner layers of the plurality of layers of the input winding. An output winding is wound around the energy transfer element core with substantially the same number of turns as the number of turns of the outer layer of the plurality of layers of the input winding to reduce substantially a capacitive displacement current flowing between the input and output windings.

Abstract: An energy transfer element with substantially reduced electrical displacement current flow between an input circuit coupled to the energy transfer element input winding and an output circuit coupled to the energy transfer element output winding. In one aspect, an energy transfer element includes an input winding, an output winding, an electrically conductive shield coupled to the input winding and a first cancellation winding coupled to the input winding. The electrically conductive shield is physically positioned between input and output windings. The output winding is physically positioned between the electrically conductive shield and the first cancellation winding. The first cancellation winding is wound to substantially reduce a capacitive displacement current between the input circuit and the output circuit.

Abstract: An energy transfer element with substantially reduced electrical displacement current flow between an input circuit coupled to the energy transfer element input winding and an output circuit coupled to the energy transfer element output winding. In one aspect, an energy transfer element includes an input winding, an output winding, an electrically conductive shield coupled to the input winding and a first cancellation winding coupled to the input winding. The electrically conductive shield is physically positioned between input and output windings. The output winding is physically positioned between the electrically conductive shield and the first cancellation winding. The first cancellation winding is wound to substantially reduce a capacitive displacement current between the input circuit and the output circuit.

Abstract: Techniques are disclosed to regulate a power supply with a compensation signal generation circuit. One example regulated power supply includes a sense circuit coupled to sense an output voltage of the regulated power supply. The regulated power supply also includes a switching power converter circuit, which includes a switch coupled to be switched in response to a control signal received from the sense circuit to regulate the output voltage of the regulated power supply. The regulated power supply also includes a compensation signal generation circuit coupled to receive a switching signal representative of a switching of the switch in the switching power converter circuit. The compensation signal generation circuit is to generate a compensation signal responsive to the switching signal. The compensation signal is to be received by the sense circuit to modify the control signal.

Abstract: Methods for winding energy transfer element cores are disclosed. In one aspect, a method includes winding a plurality of layers of an input winding around an energy transfer element core. One layer of the input winding is wound with a number of turns different than a number of turns included in other layers of the input winding. An output winding is wound around the energy transfer element core with substantially the same number of turns as the number of turns of the one layer of the input winding to reduce substantially a capacitive displacement current flowing between the input and output windings.

Abstract: An energy transfer element having windings. In one aspect, the energy transfer element includes a first winding wound around a core, the first winding has a first end and a second end. A second winding is wound around the core. The second winding has a first end and a second end. The first winding is capacitively coupled to the second winding to provide a transfer of energy from the first winding to the second winding. A third winding is wound around the core. The third winding has a first end and a second end. The first end of the third winding is electrically coupled to the first end of the second winding. The second end of the third winding is uncoupled such that an influence of an electrostatic field to be produced by the first and second windings relative to the core are to be cancelled by an electrostatic field to be created by the third winding.

Abstract: An energy transfer element having an energy transfer element input winding and an energy transfer element output winding. In one aspect, the energy transfer element input winding is capacitively coupled to the energy transfer element output winding. The energy transfer element is capacitively coupled to electrical earth. One or more additional windings are introduced as part of the energy transfer element. The one or more additional windings substantially reduce capacitive displacement current between the energy transfer element input winding and energy transfer element output winding by balancing the relative electrostatic fields generated between these windings and/or between the energy transfer element and electrical earth by canceling the electrostatic fields generated by all windings within the energy transfer element relative to electrical earth through the selection of the physical position and number of turns in the additional windings.

Abstract: A voltage sense circuit and power supply regulation technique. In one aspect, a voltage sense circuit utilized in a power supply regulator includes a transformer including a sense winding and an output winding. A first diode is coupled to the sense winding, a first resistor is coupled to the first diode and a first capacitor coupled to the first resistor and the first diode. A second diode coupled to the first capacitor, the first resistor and the first diode. A second capacitor coupled to the second diode such that a voltage across the second capacitor is representative of a voltage across the output winding.

Abstract: An energy transfer element with substantially reduced electrical displacement current flow between an input circuit coupled to the energy transfer element input winding and an output circuit coupled to the energy transfer element output winding. In one aspect, an energy transfer element includes an input winding, an output winding, an electrically conductive shield coupled to the input winding and a first cancellation winding coupled to the input winding. The electrically conductive shield is physically positioned between input and output windings. The output winding is physically positioned between the electrically conductive shield and the first cancellation winding. The first cancellation winding is wound to substantially reduce a capacitive displacement current between the input circuit and the output circuit.

Abstract: An energy transfer element having an energy transfer element input winding and an energy transfer element output winding. In one aspect, the energy transfer element input winding is capacitively coupled to the energy transfer element output winding. The energy transfer element is capacitively coupled to electrical earth. Capacitive displacement current between the energy transfer element input winding and energy transfer element output winding is substantially reduced by balancing the relative electrostatic fields generated between these windings and/or between the energy transfer element and electrical without any additional windings.

Abstract: An energy transfer element having an energy transfer element input winding and an energy transfer element output winding. In one aspect, the energy transfer element input winding is capacitively coupled to the energy transfer element output winding. The energy transfer element is capacitively coupled to electrical earth. Capacitive displacement current between the energy transfer element input winding and energy transfer element output winding is substantially reduced by balancing the relative electrostatic fields generated between these windings and/or between the energy transfer element and electrical without any additional windings.

Abstract: A voltage sense circuit and power supply regulation technique. In one aspect, a voltage sense circuit utilized in a power supply regulator includes a transformer including a sense winding and an output winding. A first diode is coupled to the sense winding, a first resistor is coupled to the first diode and a first capacitor coupled to the first resistor and the first diode. A second diode coupled to the first capacitor, the first resistor and the first diode. A second capacitor coupled to the second diode such that a voltage across the second capacitor is representative of a voltage across the output winding.