Abstract: A two-wire load control device for control of power delivered to an electrical load from a source of AC voltage, comprising a first controllably conductive device adapted to be operatively coupled to the source of AC voltage and to the electrical load for controlling the power delivered to the load; a microprocessor coupled to the first controllably conductive device for controlling the first controllably conductive device; and a power supply adapted to be coupled to the source of AC voltage and coupled to the microprocessor for generating a DC voltage to power the microprocessor, the power supply including an energy storage element and a second controllably conductive device for controllably storing energy in the energy storage element; wherein the microprocessor is operatively coupled to the second controllably conductive device to control the second controllably conductive device.

Abstract: A ballasted lamp socket for a gas discharge lamp, such as a compact fluorescent lamp, is adapted to replace an Edison screw-in lamp socket in a ceiling mounted light fixture, or a table or floor lamp. The ballasted lamp socket comprises a lamp-receiving portion adapted to be coupled to the gas discharge lamp, an enclosure mechanically coupled to the lamp-receiving portion, a dimming ballast circuit electrically coupled to the lamp-receiving portion and housed within the enclosure, and first and second electrical connections. The ballast portion is adapted to receive an AC line voltage and to generate a high-frequency AC voltage for driving the gas discharge lamp and controlling the light intensity of the gas discharge lamp between a high-end intensity and a low-end intensity. The first and second electrical connections are operable to receive the AC line voltage and to provide the AC line voltage to the ballast circuit.

Abstract: A dimmable ballast circuit for a compact fluorescent lamp controls the intensity of a lamp tube in response to a phase-control voltage received from a dimmer switch. The ballast circuit generates a lamp current through the lamp tube having a substantially constant envelope such that flicker in the lamp tube and electromagnetic interference (EMI) noise on an AC voltage supply are minimized. The dimmable ballast circuit comprises a high speed control circuit characterized by a cutoff frequency much greater than a frequency of a voltage ripple on a bus voltage of the ballast circuit. The dimmable ballast circuit may also comprise a non-linear amplifier circuit amplifying a lamp-current-feedback signal representative of the magnitude of the lamp current through the lamp.

Abstract: A hybrid light source comprises a discrete-spectrum lamp (for example, a fluorescent lamp) and a continuous-spectrum lamp (for example, a halogen lamp). A control circuit individually controls the amount of power delivered to the discrete-spectrum lamp and the continuous-spectrum lamp in response to a phase-controlled voltage generated by a connected dimmer switch, such that a total light output of the hybrid light source ranges throughout a dimming range. The continuous-spectrum lamp is driven by a continuous-spectrum lamp drive circuit, which is operable to conduct a charging current of a power supply of the dimmer switch and to provide a path for enough current to flow through the hybrid light source, such that the magnitude of the current exceeds rated latching and holding currents of a thyristor of the dimmer.

Abstract: A motorized window treatment controls daylight entering a space through a window and includes a covering material, a drive shaft, lift cords received around the drive shaft and connected to the covering material, and a motor coupled to the drive shaft. It also includes a spring assist unit for the motor providing a torque that equals the torque provided by the weight on the lift cords at a position midway between fully-open and fully-closed positions, minimizing motor usage and conserving battery life. A photosensor for measuring the daylight outside the window and temperature sensors for measuring the temperatures inside and outside of the window may be provided. The position of the covering material is automatically controlled to save energy, or may also be controlled in response to an infrared or radio-frequency remote control.

Abstract: A load control device for control of the power delivered from an AC power source to an electrical load comprises a power supply and a microprocessor that is able to operate the load control device in a low-power mode. The load control device may further comprise at least one visual indicator controlled by the microprocessor to provide visual feedback, where the microprocessor illuminates the visual indicator when the load is on and to turns the visual indicator off when the load is off during the low-power mode. The load control device may comprise a communication circuit coupled to the microprocessor for transmitting and/or receiving digital messages the microprocessor cause the communication circuit to draw less current from the power supply during the low-power mode. The microprocessor may operate in the low-power mode if the magnitude of a voltage of the power supply drops below a predetermined threshold.

Abstract: A two-wire load control device (such as, a dimmer switch) for controlling the amount of power delivered from an AC power source to an electrical load (such as, a high-efficiency lighting load) includes a thyristor coupled between the source and the load, a gate coupling circuit coupled between a first main load terminal and the gate of the thyristor, and a control circuit coupled to a control input of the gate coupling circuit. The control circuit generates a drive voltage for causing the gate coupling circuit to conduct a gate current to thus render the thyristor conductive at a firing time during a half cycle of the AC power source, and to allow the gate coupling circuit to conduct the gate current at any time from the firing time through approximately the remainder of the half cycle, where the gate coupling circuit conducts approximately no net average current to render and maintain the thyristor conductive.

Abstract: A hybrid light source comprises a high-efficiency lamp, for example, a fluorescent lamp, and a low-efficiency lamp, for example, a halogen lamp. A control circuit individually controls the amount of power delivered to each of the high-efficiency lamp and the low-efficiency lamp, such that a total light output of the hybrid light source ranges throughout a dimming range from a minimum total intensity to a maximum total intensity. The high-efficiency lamp is turned off and the low-efficiency lamp produces all of the total light intensity of the hybrid light source when the total light intensity is below a transition intensity. The low-efficiency lamp is controlled such that the correlated color temperature of the hybrid light source decreases as the total light intensity is decreased below the transition intensity. The hybrid light source is characterized by a low impedance throughout the dimming range.

Abstract: An electronic ballast for driving a gas discharge lamp comprises an inverter circuit that operates in a partially self-oscillating manner. The inverter circuit comprises a push-pull converter having a main transformer having a primary winding for producing a high-frequency AC voltage, semiconductor switches electrically coupled to the primary winding of the main transformer for conducting current through the primary winding on an alternate basis, and gate drive circuits for controlling the semiconductor switches on a cycle-by-cycle basis. The drive circuits control (e.g., turn on) the semiconductor switches in response to first control signals derived from the main transformer, and control (e.g., turn off) the semiconductor switches in response to second control signals received from a control circuit. The control circuit controls the semiconductor switches in response to a peak value of an integral of an inverter current flowing through the inverter circuit.

Abstract: A hybrid light source comprises a discrete-spectrum lamp (for example, a fluorescent lamp) and a continuous-spectrum lamp (for example, a halogen lamp). A control circuit individually controls the amount of power delivered to the discrete-spectrum lamp and the continuous-spectrum lamp in response to a phase-controlled voltage generated by a connected dimmer switch, such that a total light output of the hybrid light source ranges throughout a dimming range. The discrete-spectrum lamp is turned off and the continuous-spectrum lamp produces all of the total light intensity of the hybrid light source when the total light intensity is below a transition intensity.

Abstract: A two-wire load control device (such as, a dimmer switch) for controlling the amount of power delivered from an AC power source to an electrical load (such as, a high-efficiency lighting load) includes a thyristor coupled between the source and the load, a gate coupling circuit coupled between a first main load terminal and the gate of the thyristor, and a control circuit coupled to a control input of the gate coupling circuit. The control circuit generates a drive voltage for causing the gate coupling circuit to conduct a gate current to thus render the thyristor conductive at a firing time during a half cycle of the AC power source, and to allow the gate coupling circuit to conduct the gate current at any time from the firing time through approximately the remainder of the half cycle, where the gate coupling circuit conducts approximately no net average current to render and maintain the thyristor conductive.

Abstract: An auxiliary power system for an electrical load in a vehicle electrical system includes an auxiliary battery, a thermal transducer in physical contact with the auxiliary battery, a charger circuit for controlling the charging of the battery in response to at least a temperature of the auxiliary battery, and an output power delivery circuit for providing power to an electrical load during normal and emergency conditions. The auxiliary power system is housed in a thermally-conductive enclosure that is in thermal communication with the charger circuit and the power delivered circuit. The power delivery circuit selectively delivers power to the electrical output from both an electrical input terminal and from the battery based on the magnitude of a voltage available on the electrical input terminal.

Abstract: A load control device for controlling an amount of power delivered to an electrical load from an AC power source, the load control device comprising a semiconductor switch operable to be coupled in series electrical connection between the source and the load, the semiconductor switch having a control input for controlling the semiconductor switch between a non-conductive state and a conductive state; a controller operatively coupled to the control input of the semiconductor switch for controlling the semiconductor switch between the non-conductive state and the conductive state; a touch sensitive front surface; a touch sensitive device responsive to a point actuation on the touch sensitive front surface, the point actuation characterized by a position and a force, the touch sensitive device comprising a resistive divider and an output operatively coupled to the controller for providing a control signal to the controller; and a capacitor coupled to the output of the touch sensitive device for stabilizing the c

Abstract: An electronic ballast for driving a gas discharge lamp comprises an inverter circuit that operates in a partially self-oscillating manner. The inverter circuit comprises a push-pull converter having a main transformer having a primary winding for producing a high-frequency AC voltage, semiconductor switches electrically coupled to the primary winding of the main transformer for conducting current through the primary winding on an alternate basis, and gate drive circuits for controlling the semiconductor switches on a cycle-by-cycle basis. The drive circuits control (e.g., turn on) the semiconductor switches in response to first control signals derived from the main transformer, and control (e.g., turn off) the semiconductor switches in response to second control signals received from a control circuit. The control circuit controls the semiconductor switches in response to a peak value of an integral of an inverter current flowing through the inverter circuit.

Abstract: A hybrid light source comprises a high-efficiency lamp, for example, a fluorescent lamp, and a low-efficiency lamp, for example, a halogen lamp. A control circuit individually controls the amount of power delivered to each of the high-efficiency lamp and the low-efficiency lamp, such that a total light output of the hybrid light source ranges throughout a dimming range from a minimum total intensity to a maximum total intensity. The high-efficiency lamp is turned off and the low-efficiency lamp produces all of the total light intensity of the hybrid light source when the total light intensity is below a transition intensity. The low-efficiency lamp is controlled such that the correlated color temperature of the hybrid light source decreases as the total light intensity is decreased below the transition intensity. The hybrid light source is characterized by a low impedance throughout the dimming range.

Abstract: An electronic ballast for driving a gas discharge lamp having first and second electrodes comprises an inverter circuit and a symmetric resonant tank circuit for minimizing the RFI noise produced at the electrodes of the lamp. The inverter circuit receives a substantially DC bus voltage generates a high-frequency AC voltage. The symmetric resonant tank circuit comprises a split resonant inductor having first and second windings magnetically coupled together. The first and second windings electrically coupled between the respective electrodes of the lamp and the inverter circuit. The symmetric resonant tank further comprises first and second capacitors coupled in series electrical connection between the electrodes of the lamp with the junction of the first and second capacitors coupled to the DC bus voltage at the input of the inverter circuit.

Abstract: An electronic ballast for driving a gas discharge lamp comprises an inverter circuit that operates in a partially self-oscillating manner. The inverter circuit comprises a push-pull converter having a main transformer having a primary winding for producing a high-frequency AC voltage, semiconductor switches electrically coupled to the primary winding of the main transformer for conducting current through the primary winding on an alternate basis, and gate drive circuits for controlling the semiconductor switches on a cycle-by-cycle basis. The drive circuits control (e.g., turn on) the semiconductor switches in response to first control signals derived from the main transformer, and control (e.g., turn off) the semiconductor switches in response to second control signals received from a control circuit. The control circuit controls the semiconductor switches in response to a peak value of an integral of an inverter current flowing through the inverter circuit.

Abstract: An electronic ballast for driving a gas discharge lamp comprises a measurement circuit for measuring a lamp current flowing through the lamp and a lamp voltage produced across the lamp. The ballast comprises a first winding magnetically coupled to a main transformer of an inverter circuit, and a second winding magnetically coupled to a resonant inductor of a resonant tank circuit. The first and second windings are coupled in series electrical connection to generate a voltage representative of the magnitude of the lamp voltage. The ballast further comprises a current transformer having primary windings coupled in series with the electrodes of the lamp. The measurement circuit integrates the current conducted through secondary windings of the current transformer only during every other half-cycle of the lamp voltage to generate a control signal representative of the magnitude of the lamp current that is in-phase with the lamp voltage.

Abstract: A user interface for a lighting control has a touch sensitive front surface; a four-wire resistive touch pad responsive to a point actuation on the front surface, the touch pad having a longitudinal resistive element for providing a first control signal representative of the position of the point actuation along the longitudinal axis, and a lateral resistive element for providing a second control signal representative of the position of the point actuation along the lateral axis; a controller receiving the first and second control signals; a first capacitor coupled between the lateral resistive element and a circuit common that charges and discharges through the longitudinal resistive element of the resistive touch pad to stabilize the first control signal; and first, second, and third switches controlled by the controller to provide a DC supply voltage to the resistive elements and to couple a respective resistive element to the controller.

Abstract: A hybrid light source comprises a high-efficiency lamp, for example, a fluorescent lamp, and a low-efficiency lamp, for example, a halogen lamp. A control circuit individually controls the amount of power delivered to each of the high-efficiency lamp and the low-efficiency lamp, such that a total light output of the hybrid light source ranges throughout a dimming range from a minimum total intensity to a maximum total intensity. The high-efficiency lamp is turned off and the low-efficiency lamp produces all of the total light intensity of the hybrid light source when the total light intensity is below a transition intensity. The low-efficiency lamp is controlled such that the correlated color temperature of the hybrid light source decreases as the total light intensity is decreased below the transition intensity. The hybrid light source is characterized by a low impedance throughout the dimming range.