Patent application number | Description | Published |
20090115345 | HIGH EFFICIENCY OFF-LINE LINEAR POWER SUPPLY - A power supply circuit comprising a charge storage capacitor having a first capacitor terminal adapted to provide a power supply voltage of the power supply and a second capacitor terminal coupled to a circuit common; a first switching device having a first switching terminal adapted to be connected to a voltage source, a second switching terminal operatively coupled to the first capacitor terminal of the charge storage capacitor, and a control terminal, the first switching device characterized by a control terminal switching threshold voltage, the first switching device adapted to conduct a charging current from the first switching terminal to the second switching terminal and into the charge storage capacitor; a control circuit controlling an on/off operation of the first switching device whereby the first switching device is operable to turn on when the magnitude of the voltage of the voltage source is below a predetermined level and turn off when the magnitude of the voltage of the voltage source is above the predetermined level; and a control voltage supply circuit operatively coupled between the first switching terminal of the first switching device and the first capacitor terminal of the charge storage capacitor, the control voltage supply circuit providing a control supply voltage; wherein a control terminal voltage derived from the control supply voltage is provided to the control terminal of the first switching device when the control circuit controls the first switching device to be on, the control terminal voltage having a magnitude in excess of the switching threshold voltage, thereby driving the switching device on in a saturated region of operation. | 05-07-2009 |
20100138067 | LIGHTING CONTROL DEVICE FOR USE WITH LIGHTING CIRCUITS HAVING THREE-WAY SWITCHES - A lighting control device adapted to be coupled to a circuit including an AC power source, an electrical load, and a single-pole double-throw three-way switch, the three-way switch comprising a first fixed contact, a second fixed contact, and a movable contact adapted to be coupled to either the power source or the load, the three-way switch having a first state in which the movable contact is contacting the first fixed contact and a second state in which the movable contact is contacting the second fixed contact, the lighting control device comprising a first load terminal adapted to be coupled to either the power source or the load to which the three-way switch is not coupled; a second load terminal adapted to be coupled to the first fixed contact of the three-way switch; a third load terminal adapted to be coupled to the second fixed contact of the three-way switch; a controllably conductive device coupled to the first, second, and third load terminals to conduct a load current from the AC power source to the load; a sensing device electrically coupled to the third load terminal, such that when the three-way switch is in the second state, the sensing device is operable to sense an electrical characteristic associated with the third load terminal; and a controller operably coupled to the controllably conductive device and to the sensing device, the controller operable to control the controllably conductive device in response to the electrical characteristic sensed by the sensing device, so as to control the amount of power delivered to the load by rendering the controllably conductive device conductive to conduct the load current through the second terminal when the three-way switch is in the first state, and by rendering the controllably conductive device conductive to conduct the load current through the third load terminal when the three-way switch is in the second state. | 06-03-2010 |
20100145545 | DIMMER SWITCH FOR USE WITH LIGHTING CIRCUITS HAVING THREE-WAY SWITCHES - A dimmer switch adapted to be coupled to a circuit including a power source, a load, and a single-pole double-throw three-way switch, the three-way switch comprising a first fixed contact, a second fixed contact, and a movable contact adapted to be coupled to either the power source or the load, the three-way switch having a first state in which the movable contact is contacting the first fixed contact and a second state in which the movable contact is contacting the second fixed contact, the dimmer switch comprising a first load terminal adapted to be coupled to either the power source or the load to which the three-way switch is not coupled for conducting a load current through the load; a second load terminal adapted to be coupled to the first fixed contact of the three-way switch; a third load terminal adapted to be coupled to the second fixed contact of the three-way switch; a first controllably conductive device electrically coupled between the first and second load terminals, such that the first controllably conductive device is operable to conduct the load current through the second load terminal to control the amount of power delivered to the load when the three-way switch is in the first state; a second controllably conductive device electrically coupled between the first and third load terminals, such that the second controllably conductive device is operable to conduct the load current through the third load terminal to control the amount of power delivered to the load when the three-way switch is in the second state; and a controller operably coupled to the first and second controllably conductive devices for rendering the first and second controllably conductive devices conductive and non-conductive, so as to control the amount of power delivered to the load. | 06-10-2010 |
20110162946 | Load Control Device Having A Visual Indication of Energy Savings and Usage Information - A dimmer switch for controlling the amount of power delivered to and thus the intensity of a lighting load comprises a visual display operable to provide a visual indication representative of energy savings and usage information. The dimmer switch comprises an intensity adjustment actuator, such as a slider knob or a rotary knob, which may be coupled to a potentiometer for adjusting the amount of power delivered to the lighting load. The potentiometer may comprise a dual potentiometer including a resistive element and a conductive element having a cut. The visual display may comprise a single visual indicator, which may be illuminated a first color, such as green, when the intensity of the lighting load is less than or equal to the eco-level intensity, and illuminated a second different color, such as red, when the intensity of the lighting load is greater than the eco-level intensity. | 07-07-2011 |