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The current and voltage across the thermistor depend on the particular circuit configuration. As a simple example, if the voltage across the thermistor is held fixed, then by Ohm's law we have = /, and the equilibrium equation can be solved for the ambient temperature as a function of the measured resistance of the thermistor:
Thermal cutoff. An assortment of thermal fuses. A thermal cutoff is an electrical safety device (either a thermal fuse or thermal switch) that interrupts electric current when heated to a specific temperature. These devices may be for one-time use (a thermal fuse), or may be reset manually or automatically (a thermal switch).
A positive-temperature-coefficient heating element (PTC heating element), or self-regulating heater, is an electrical resistance heater whose resistance increases significantly with temperature. The name self-regulating heater comes from the tendency of such heating elements to maintain a constant temperature when supplied by a given voltage ...
A thermostat is a regulating device component which senses the temperature of a physical system and performs actions so that the system's temperature is maintained near a desired setpoint. Thermostats are used in any device or system that heats or cools to a setpoint temperature.
A vacuum tube, electron tube, [1][2][3] valve (British usage), or tube (North America) [4] is a device that controls electric current flow in a high vacuum between electrodes to which an electric potential difference has been applied. The type known as a thermionic tube or thermionic valve utilizes thermionic emission of electrons from a hot ...
In control theory, a bang–bang controller (hysteresis, 2 step or on–off controller), is a feedback controller that switches abruptly between two states. These controllers may be realized in terms of any element that provides hysteresis. They are often used to control a plant that accepts a binary input, for example a furnace that is either ...
Johnson 's 1927 experiment showed that if thermal noise from a resistance of with temperature is bandlimited to bandwidth , then its root mean squared voltage is in general, where is the Boltzmann constant. Johnson–Nyquist noise (thermal noise, Johnson noise, or Nyquist noise) is the electronic noise generated by the thermal agitation of the ...
A thyristor (/ θ aɪ ˈ r ɪ s t ər /, from a combination of Greek language θύρα, meaning "door" or "valve", and transistor [1]) is a solid-state semiconductor device which can be thought of as being a highly robust and switchable diode, allowing the passage of current in one direction but not the other, often under control of a gate electrode, that is used in high power applications ...