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.

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.

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.

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.

A load control device for controlling the power delivered from an AC power source to an electrical load includes a thyristor, a gate coupling circuit for conducting a gate current through a gate of the thyristor, and a control circuit for controlling the gate coupling circuit to conduct the gate current through a first current path to render the thyristor conductive at a firing time during a half cycle. The gate coupling circuit is able to conduct the gate current through the first current path again after the firing time, but the gate current is not able to be conducted through the gate from a transition time before the end of the half-cycle until approximately the end of the half-cycle. The load current is able to be conducted through a second current path to the electrical load after the transition time until approximately the end of the half-cycle.

A load control device for controlling the power delivered from an AC power source to an electrical load includes a thyristor, a gate coupling circuit for conducting a gate current through a gate of the thyristor, and a control circuit for controlling the gate coupling circuit to conduct the gate current through a first current path to render the thyristor conductive at a firing time during a half cycle. The gate coupling circuit is able to conduct the gate current through the first current path again after the firing time, but the gate current is not able to be conducted through the gate from a transition time before the end of the half-cycle until approximately the end of the half-cycle. The load current is able to be conducted through a second current path to the electrical load after the transition time until approximately the end of the half-cycle.

A load control device may include a semiconductor switch, a control circuit, and first and second terminals adapted to be coupled to a remote device. The load control device may include a first switching circuit coupled to the second terminal, and a second switching circuit coupled between the first terminal and the second terminal. The control circuit may be configured to render the first switching circuit conductive to conduct a charging current from an AC power source to a power supply of the remote device during a first time period of a half-cycle of the AC power source, and further configured to render the first and second switching circuits conductive and non-conductive to communicate with the remote device via the second terminal during a second time period of the half-cycle of the AC power source.

A load control device may include a semiconductor switch, a control circuit, and first and second terminals adapted to be coupled to a remote device. The load control device may include a first switching circuit coupled to the second terminal, and a second switching circuit coupled between the first terminal and the second terminal. The control circuit may be configured to render the first switching circuit conductive to conduct a charging current from an AC power source to a power supply of the remote device during a first time period of a half-cycle of the AC power source, and further configured to render the first and second switching circuits conductive and non-conductive to communicate with the remote device via the second terminal during a second time period of the half-cycle of the AC power source.

Provided is a radiation light source that enables adjustment of infrared radiation to a significantly narrow band. A plasmonic reflector layer consisting of a plasmonic material, a resonator layer consisting of an insulator, and a partially reflecting layer are alternately laminated in this order to form a multi-layered radiation light source, wherein the partially reflecting layer are selected from any one of a free interface, an ultrathin-film metallic layer, and a distributed reflector layer having a structure in which layers having different refractive indexes are alternately laminated. When a material with high-temperature resistance such as SiC is used in the outermost layer of the distributed reflector layer, the multi-layered radiation light source can operate at high temperatures of 550° C. and higher.

A LED controller includes an image buffer to hold image data. An LED pixel forming a part of a large pixel array is activatable in response to image data, LDO state, and pulse width modulation module state. A logic module including a pixel diagnostic mode using an LDO bypass is connected to modify LDO state and allow direct addressing of the LED pixel for diagnostic purposes without needing to use image data from the image buffer.