Abstract: A power switch includes a bridge-connected switching circuit with (1) a pair of MOSFETs back-to-back in series between line and load connections, an interconnection point of the MOSFETs being a first common connection, and (2) a pair of diodes back-to-back between the line and load connections, an interconnection point of the diodes being a second common connection. A line/load controller has supply inputs connected to the first and second common connections for receiving operating power, and (1) places both MOSFETs in the ON state to deliver normal operating current to the load for normal operation, and (2) places both MOSFETs in the OFF state to deliver (by body diode conduction) a substantially reduced leakage current to the load when the load is not powered for normal operation, the leakage current providing the operating power to the line/load controller.

Abstract: A power switching device is provided with an integrated current sensor. The device includes component housing and multiple terminal legs extending therefrom. A current sensor assembly includes an interior cavity having a galvanically insulating tubular sleeve extending therethrough. A toroidal inductive winding resides within the first cavity and is circumferentially disposed about the sleeve, with one leg of the device defining a (single-turn) primary winding and the winding defining a secondary winding magnetically coupled to the device leg. Current sensing terminals are associated with respective locations along the inductive winding, wherein a current through the encapsulated terminal leg is detectable via respective current sensing leads extending from the assembly housing. A damping inductive element such as a ferrite bead may be provided within a second interior cavity defined by the assembly housing to suppress high frequency oscillations associated with a second (e.g.

Abstract: A power supply includes power circuitry configured to provide DC power to a separate load, and wireless communication circuitry for wirelessly communicating with an external control device such as a smart phone. A controller is configured to (1) conduct communications with the external control device via the wireless communication circuitry to receive configuration parameters, and (2) incorporate the configuration parameters into a control scheme for operation of the power supply. The power supply may be used with an LED lamp including a series of LEDs, and the configuration parameters establish desired operating characteristics including selection of constant-current or constant-voltage operation, and/or parameters for a dimming curve applied in dimming operation of the LED lamp. The power supply may be used in other applications including battery charging applications.

Abstract: A power switch includes a bridge-connected switching circuit with (1) a pair of MOSFETs back-to-back in series between line and load connections, an interconnection point of the MOSFETs being a first common connection, and (2) a pair of diodes back-to-back between the line and load connections, an interconnection point of the diodes being a second common connection. A line/load controller has supply inputs connected to the first and second common connections for receiving operating power, and (1) places both MOSFETs in the ON state to deliver normal operating current to the load for normal operation, and (2) places both MOSFETs in the OFF state to deliver (by body diode conduction) a substantially reduced leakage current to the load when the load is not powered for normal operation, the leakage current providing the operating power to the line/load controller.

Abstract: A power converter startup circuit establishes an operating voltage for control circuitry during startup and is then disabled to reduce no-load power dissipation. The startup circuit has a normally on characteristic to automatically provide startup charging current for a startup capacitor. The control circuitry begins operating as the startup capacitor voltage reaches an operating value, and it generates an inhibitory signal that disables the startup circuit to stop the startup charging current and reduce power dissipation. The normally on characteristic is achieved by an emitter switched current source employing a normally on device such as a depletion-mode J-FET. A resistor divider network provides both biasing for the startup current source and a point of monitoring the power supply input voltage during steady state operation. A charge pump provides a voltage of the inhibitory control signal sufficiently above the auxiliary voltage to turn off the normally on switching transistor.

Abstract: A power converter startup circuit establishes an operating voltage for control circuitry during startup and is then disabled to reduce no-load power dissipation. The startup circuit has a normally on characteristic to automatically provide startup charging current for a startup capacitor. The control circuitry begins operating as the startup capacitor voltage reaches an operating value, and it generates an inhibitory signal that disables the startup circuit to stop the startup charging current and reduce power dissipation. The normally on characteristic is achieved by an emitter switched current source employing a normally on device such as a depletion-mode J-FET. A resistor divider network provides both biasing for the startup current source and a point of monitoring the power supply input voltage during steady state operation.

Abstract: A power supply includes power circuitry configured to provide DC power to a separate load, and wireless communication circuitry for wirelessly communicating with an external control device such as a smart phone. A controller is configured to (1) conduct communications with the external control device via the wireless communication circuitry to receive configuration parameters, and (2) incorporate the configuration parameters into a control scheme for operation of the power supply. The power supply may be used with an LED lamp including a series of LEDs, and the configuration parameters establish desired operating characteristics including selection of constant-current or constant-voltage operation, and/or parameters for a dimming curve applied in dimming operation of the LED lamp. The power supply may be used in other applications including battery charging applications.

Abstract: A regulated switching power converter generates a converter output having first and second regulated output values under corresponding operating conditions. The converter output transitions between the first and second output values in response to transition of a trigger signal in a transition window between first and second trigger values. A transition step function is based on transition amplitude, transition interval and number of steps, the transition amplitude being a difference between the first and second regulated output values, and the transition interval being a difference between the first and second trigger values. The transition step function generates a step-like transition signal based on values of the trigger signal between the first and second trigger values. During operation in the transition window, the step-like transition signal is included in the regulation reference value to generate a step-like transition of the converter output between the first and second regulated output values.

Abstract: A power supply includes signaling circuitry coupled to output terminals for engaging in bidirectional communications with a load. A controller is capable of conducting the bidirectional communications and selecting among different operating modes for the power supply based on the communications. The modes may include a constant-current mode suitable for applications such as battery charging and power LED lamps, and a constant-voltage mode suitable for a variety of conventional uses such as powering electronic circuitry. The signaling circuitry may include a power switching transistor in series with the load, which is pulsed in a binary fashion to transmit communications to the load. A signal-forming resistor in parallel with the power switching transistor develops a signaling voltage monitored by the controller to receive communications from the load.

Abstract: A power converter startup circuit establishes an operating voltage for control circuitry during startup and is then disabled to reduce no-load power dissipation. The startup circuit has a normally on characteristic to automatically provide startup charging current for a startup capacitor. The control circuitry begins operating as the startup capacitor voltage reaches an operating value, and it generates an inhibitory signal that disables the startup circuit to stop the startup charging current and reduce power dissipation. The normally on characteristic is achieved by an emitter switched current source employing a normally on device such as a depletion-mode J-FET. A resistor divider network provides both biasing for the startup current source and a point of monitoring the power supply input voltage during steady state operation.

Abstract: A power supply system includes a digital power manager and multiple power blocks each conveying regulated power to a respective load. The power blocks include the power part of non-isolated DC/DC converters, signal sampling and conversion circuits to provide analog voltage signal representing output voltage, output current, temperature, etc., and driving circuits to receive pulse width modulation (PWM) signals and drive switching devices. Closed-loop voltage control and protection functions for the power blocks are integrated into the digital power. The digital power manager includes a non-volatile memory containing registers, including a digital power manager configuration register, a power block set-up register, and a power block monitor register, as well as a user-definable space.

Abstract: A regulated switching power converter generates a converter output having first and second regulated output values under corresponding operating conditions. The converter output transitions between the first and second output values in response to transition of a trigger signal in a transition window between first and second trigger values. A transition step function is based on transition amplitude, transition interval and number of steps, the transition amplitude being a difference between the first and second regulated output values, and the transition interval being a difference between the first and second trigger values. The transition step function generates a step-like transition signal based on values of the trigger signal between the first and second trigger values. During operation in the transition window, the step-like transition signal is included in the regulation reference value to generate a step-like transition of the converter output between the first and second regulated output values.

Abstract: A power supply includes signaling circuitry coupled to output terminals for engaging in bidirectional communications with a load. A controller is capable of conducting the bidirectional communications and selecting among different operating modes for the power supply based on the communications. The modes may include a constant-current mode suitable for applications such as battery charging and power LED lamps, and a constant-voltage mode suitable for a variety of conventional uses such as powering electronic circuitry. The signaling circuitry may include a power switching transistor in series with the load, which is pulsed in a binary fashion to transmit communications to the load. A signal-forming resistor in parallel with the power switching transistor develops a signaling voltage monitored by the controller to receive communications from the load.

Abstract: A DC/DC converter for use in power supply applications employing multiple parallel-connected converters employs a digital controller referenced to the secondary or output side of an isolation boundary and having non-isolated direct connections to secondary side components. The controller directly monitors output voltage and output current and uses feedback control techniques to precisely control these values in a desired manner. The DC/DC converter can implement so-called “droop” current sharing with increased accuracy arising from the secondary-side digital control, so that a desired balanced sharing of current across multiple converters can be achieved. The converter uses calibration establish accurate set points, and any of a variety of additional functions/features to attain operational goals.

Abstract: A DC/DC converter for use in power supply applications employing multiple parallel-connected converters employs a digital controller referenced to the secondary or output side of an isolation boundary and having non-isolated direct connections to secondary side components. The controller directly monitors output voltage and output current and uses feedback control techniques to precisely control these values in a desired manner. The DC/DC converter can implement so-called “droop” current sharing with increased accuracy arising from the secondary-side digital control, so that a desired balanced sharing of current across multiple converters can be achieved. The converter uses calibration establish accurate set points, and any of a variety of additional functions/features to attain operational goals.

Abstract: A power supply for an LED lamp has a set of coupled coils, primary-side power circuitry including a converter power switch for conducting input power, and secondary-side power circuitry including a dimming power switch. Power control circuitry includes converter control circuitry which generates a converter control signal for the converter power switch to maintain a desired undimmed level of lamp current at a normal operating value of a lamp voltage. Dimming control circuitry generates a dimming control signal for the dimming power switch to pulse-width modulate the lamp current at a duty cycle corresponding to a desired dimming. Operation of the converter control circuitry is modified during dimming to prevent an automatic increase of the lamp voltage in response to a decrease in lamp current, avoiding undesirable overshooting of the lamp current and providing more accurate and effective control over dimming operation.

Abstract: A power supply system includes a digital power manager and multiple power blocks each conveying regulated power to a respective load. The power blocks include the power part of non-isolated DC/DC converters, signal sampling and conversion circuits to provide analog voltage signal representing output voltage, output current, temperature, etc., and driving circuits to receive pulse width modulation (PWM) signals and drive switching devices. Closed-loop voltage control and protection functions for the power blocks are integrated into the digital power. The digital power manager includes a non-volatile memory containing registers, including a digital power manager configuration register, a power block set-up register, and a power block monitor register, as well as a user-definable space.

Abstract: A power supply for an LED lamp has a set of coupled coils, primary-side power circuitry including a converter power switch for conducting input power, and secondary-side power circuitry including a dimming power switch. Power control circuitry includes converter control circuitry which generates a converter control signal for the converter power switch to maintain a desired undimmed level of lamp current at a normal operating value of a lamp voltage. Dimming control circuitry generates a dimming control signal for the dimming power switch to pulse-width modulate the lamp current at a duty cycle corresponding to a desired dimming. Operation of the converter control circuitry is modified during dimming to prevent an automatic increase of the lamp voltage in response to a decrease in lamp current, avoiding undesirable overshooting of the lamp current and providing more accurate and effective control over dimming operation.

Abstract: A DC/DC converter which includes a switched mode power supply, such as a switched mode buck regulator, has gate driven switching devices. A flyback converter is provided for providing a gate drive voltage to the gate driven switching devices. The flyback converter increases or decreases an input voltage to provide the gate drive voltage. A programmable under voltage lockout circuit is provided for turning ON of the flyback converter if the input voltage is lower than a predetermined value. A plurality, n, of buck regulators are connected in parallel and are controlled by a common controller which provides pulse width modulation signals to each power stage which are shifted by 360°/n from each other.

Abstract: A circuit for providing a regulated voltage to a load. The circuit includes a power converter coupled to the load and including at least one pulse-width modulated switching device, a control circuit for providing a pulse-width modulated control signal to the pulse-width modulated switching device of the power converter based on an output voltage of the power converter, and a transient override circuit responsive to a load voltage for biasing the pulse-width modulated switching device conductive during certain load voltage conditions.