Next to time, temperature is the most commonly measured parameter in the world. Whenever possible, older, non-electronic thermometers are being replaced by newer methods of electronic thermometry because the signal from an electronic temperature sensor can be used to actively control processes and log temperature events. Because a good sensor is the “cornerstone” of a good system, many engineers select NTC thermistors when designing their temperature measurement and control systems.
NTC thermistors are used for temperature measurement, monitoring, control, and compensation. Of the four areas, temperature measurement is the most common application for NTC thermistors. With off-the-shelf interchangeable temperature tolerances to ±0.1 °C, a NTC thermistor is a better choice than a thermocouple. At approximately 1/3 the cost of a resistance temperature detector (RTD), a NTC thermistor is a more cost-effective solution for temperatures in the range of -50 °C to 150 °C . A NTC thermistor has a significantly better signal-to-noise ratio than either a thermocouple or a RTD. Typically, NTC thermistors can be ordered with resistance values ranging from 100 ohms to 100,000 ohms.
Wheatstone bridge circuits, linear thermistor/resistor networks, and programmable microprocessors are some of the devices that can be used with NTC thermistors for a variety of temperature applications. NTC thermistors can also be interfaced with PC's using off-the-shelf data acquisition software and interface cards.
Because temperature is so critical in so many applications, NTC thermistors are used in a broad base of healthcare, science, industrial, military, and commercial markets with new applications developing every day. Representative applications are:
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| Automotive/Heavy Equipment | | - | Electronic Engine Control | | - | Climate control | | - | Defrost | | - | Fluid temperatures | | - | Ice detection |
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| Aviation/Aerospace | | - | Altimeters | | - | Cabin Climate Control | | - | Missiles/satellites | | - | Fire control | | - | Thermal updraft sensor |
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| Building Energy Management | | - | Thermostats | | - | Air flow sensors | | - | Chillers | | - | Heat pumps | | - | Coil temperatures | | - | Room sensors | | - | Gas sensors |
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| Chemical/Petrochemical/Industrial | | - | Tank temperatures | | - | Process controls | | - | pH sensors | | - | Water quality | | - | Environmental protection instrumentation | | - | Laser temperature compensation and over temp protection |
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Communications/Computer Technology | | - | Temperature Compensated Crystal Oscillators (TCXOs) | | - | Fiber optic networks | | - | Cell phones | | - | Battery packs | | - | Power supplies | | - | Hard drive and circuit over-temp protection | | - | Microwave temperature compensation |
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Consumer Products | | - | Home fever thermometers | | - | Meat thermometers | | - | Coffee makers | | - | Microwave ovens | | - | Home appliances | | - | Pool/spa controllers | | - | Refrigerators/freezers |
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Electrical/Electronics | | - | Temperature compensation | | - | Cold junction compensation | | - | Infrared detectors [Ambient and black body temperature] | | - | Circuit protection | | - | Semiconductor processing |
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Factory Automation | | - | Bearing over-temp protection | | - | Painting and coating processes | | - | Deposition chambers | | - | Molding temperatures |
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Food Processing | | - | Dough processing | | - | Meat/fish Curing | | - | Meat/fish Smokers | | - | Food safety/bacterial control | | - | Egg Incubation | | - | Poultry processing | | - | Storage/transport temperature control/alarms |
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Medical Devices | | - | Disposable temperature catheters | | - | Respirators | | - | NICU incubators | | - | Kidney dialysis | | - | IV Blood warmers | | - | Blood chemistry | | - | Blood oxygenators | | - | Apnea monitors | | - | Gas analyzers | | - | Myocardial temperature probes |
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Meteorology /Environmental | | - | Air balloons | | - | Land stations | | - | Ocean buoys | | - | Water quality |
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