Sensistor
Encyclopedia
Sensistor is a resistor
whose resistance changes with temperature
.
The resistance increases exponentially
with temperature, that is the temperature coefficient
is positive (eg. 0.7% per degree Celsius
).
Sensistors are used in electronic circuit
s for compensation of temperature influence or as sensors of temperature for other circuits.
Sensistors are made by using very heavily doped semiconductor
s so that their operation is similar to PTC-type thermistors
. However, very heavily doped semiconductor behaves more like a metal and the resistance change is more gradual than it is the case for other PTC thermistors.
Resistor
A linear resistor is a linear, passive two-terminal electrical component that implements electrical resistance as a circuit element.The current through a resistor is in direct proportion to the voltage across the resistor's terminals. Thus, the ratio of the voltage applied across a resistor's...
whose resistance changes with temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...
.
The resistance increases exponentially
Exponential growth
Exponential growth occurs when the growth rate of a mathematical function is proportional to the function's current value...
with temperature, that is the temperature coefficient
Temperature coefficient
The temperature coefficient is the relative change of a physical property when the temperature is changed by 1 K.In the following formula, let R be the physical property to be measured and T be the temperature at which the property is measured. T0 is the reference temperature, and ΔT is the...
is positive (eg. 0.7% per degree Celsius
Celsius
Celsius is a scale and unit of measurement for temperature. It is named after the Swedish astronomer Anders Celsius , who developed a similar temperature scale two years before his death...
).
Sensistors are used in electronic circuit
Electronic circuit
An electronic circuit is composed of individual electronic components, such as resistors, transistors, capacitors, inductors and diodes, connected by conductive wires or traces through which electric current can flow...
s for compensation of temperature influence or as sensors of temperature for other circuits.
Sensistors are made by using very heavily doped semiconductor
Semiconductor
A semiconductor is a material with electrical conductivity due to electron flow intermediate in magnitude between that of a conductor and an insulator. This means a conductivity roughly in the range of 103 to 10−8 siemens per centimeter...
s so that their operation is similar to PTC-type thermistors
Thermistor
A thermistor is a type of resistor whose resistance varies significantly with temperature, more so than in standard resistors. The word is a portmanteau of thermal and resistor...
. However, very heavily doped semiconductor behaves more like a metal and the resistance change is more gradual than it is the case for other PTC thermistors.