A voltage-controlled resistor is provided. The resistor structure includes first and second resistive elements each including a phase change material that changes resistance in response to a change in temperature of the phase change material. A heating element is arranged in thermal contact with the first and second resistive elements. A control circuit receives a selected input voltage and supplies power based on the selected input voltage to the heating element to heat the first and second resistive elements to a selected temperature. The first and second resistive elements, which are proximate to and electrically isolated from each other, have a selected resistance at the selected temperature. A feedback circuit senses a change in temperature of the first resistive element and adjusts power supplied to the heating element based on the change in temperature of the first resistive element to maintain a resistance of the second resistive element at the selected resistance.

A zero-power plasmonic microelectromechanical system (MEMS) device is capable of specifically sensing electromagnetic radiation and performing signal processing operations. Such devices are highly sensitive relays that consume no more than 10 nW of power, utilizing the energy in detected electromagnetic radiation to detect and discriminate a target without the need of any additional power source. The devices can continuously monitor an environment and wake up an electronic circuit upon detection of a specific trigger signature of electromagnetic radiation, such as vehicular exhaust, gunfire, an explosion, a fire, a human or animal, and a variety of sources of radiation from the ultraviolet to visible light, to infrared, to terahertz radiation.

The present invention relates to a system and a method for independently controlling a relay using bimetal which allow bimetal to operate based on a signal output from a micro controller unit when current of a predetermined threshold or more flows on a circuit to allow current which flows between a battery and the relay to flow bypassing the bimetal to independently control the relay regardless of whether a circuit pattern is abnormal.

Zero-power system for remote monitoring of heat sources is provided. The systems detect failure indicators of remote equipment including power substations, oil rigs, large inaccessible machinery in a factory, and communications equipment. The systems also can be used to detect the presence of people in buildings or in other locations, so as to improve HVAC utilization in large buildings. When the zero-power monitoring systems detect heat sources, such as the presence of people, failure indicators, or a targeted environmental signal, a circuit is closed using the energy of the detected radiation, and activating an RFID tag, a radio transmitter, or an alarm. The monitoring systems can remain deployed and active for many years without the need for battery replacement.

A reduced height relay block for use within a power distribution device for a vehicle electrical system. In one embodiment, there is provided a power distribution device that routes or distributes power throughout a vehicle electrical system and includes a lower housing, a relay block assembly, a module with a printed circuit board (PCB), an array of serviceable electrical components, and an upper cover. The relay block assembly includes a relay block with an upper side that is generally planar and includes a number of cavities for receiving the serviceable electrical components. An underside of the upper cover includes clearance ribs specifically designed to oppose certain serviceable electrical components and prevent them from backing out of their respective cavities.