Negative temperature coefficient thermistors
are generally simply called "thermistors".
Thermistors are a semiconducting ceramic
resistor produced by sintering the raw
materials at a high temperature and are
mainly made from metal oxide.
The resistance of a thermistor is solely a function of its
absolute temperature. It is necessary to test resistance
values at a range of temperatures, since electrical
power being dissipated within a thermistor might heat
Unless otherwise specified all B values are determined
the thermistor above its ambient temperature and
by measuring resistance at 25℃ and 85℃.
thereby reduce its resistance. The resistance so
measured is called RT, which means the resistance at
essentially zero power.
The B value
is the power
by
Measurements are taken with the thermistor
suspended by its leads in specified environments.
63.2%
Measurements
are taken with the thermistor suspended by its
leads in specified environments.
φ
Temperature sensors are assembled with various parts and
thermistor chips according to the required applications. Chips
and sensor assemblies have the same electrical characteristics.
Many different types of thermistor sensors can be utilized for
detecting or controlling temperature because thermistors have a
wide operating temperature range of -50 to 300℃. Standard
temperature sensors are available for different applications such
as liquid, air and surface temperature measurement.
Surface
air conditioners.
air conditioners.
batteries.
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AP Thermistor Series (very high accuracy type)
The AP thermistor series features an even higher accuracy
than our AT high accuracy thermistors and is used for
various types of applications.
- Extremely high accuracy: Tolerance for R25 and B25/85 is
±0.5%.
- High accuracy for a wide temperature range: Tolerance for
- 60℃ to + 70℃ is 0.5%.
Applications
Mobile devices, battery packs, fan motors, cars, office
automation, home electronics, security, thermometers.
measuring instruments (and many more)
B value variation
AP thermistor
Very high accuracy
Temperature
*1 Rated zero-power resistance value at 25℃.
*2 B value determined by rated zero-power resistance at 25℃ and 85℃.
*3 Time necessary to reach 63.2% of temperature difference. Measured in still air.
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AT Thermistor Series (high accuracy type)
The AT thermistor series features a high
accuracy (±1%) for both the resistance and the
B-value.
- Shape is unified, facilitating automatic assembly
- Long term reliability
Applications
Office automation. measuring instruments,
controllers, mobile devices, battery packs, fan
motors, home electronics, heating / cooling
devices, solar systems, security, thermometers,
automotive, vending machines, (cooled) product
showcases, agricultural applications
AT-11,AT-2
AT-4
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□
Only for AT-5:
FT = Taping
No denotation = Loose products
Shape
AT thermistor
Safety standards
(Other resistance values are also available. Please contact us.)
*1 Rated zero-power resistance value at 25℃.
*2 B value determined by rated zero-power resistance at 25℃ and 85℃.
*3 Time necessary to reach 63.2% of temperature difference. Measured in still air.
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JT Thermistor Series (high accuracy, ultra-thin type)
The JT thermistor series features a thickness of
less than 500 μm and can be installed in spaces
as thin as a telephone card. The JT thermistors
also have excellent electrical insulation and can be
safely used in environments were they might come
in contact with electrodes.
Applications
Battery packs, IT devices, mobile devices, LCDs,
surface temperature sensors, fast response air
temperature sensors
*1 Rated zero-power resistance value at 25℃. Resistance tolerance of ±2% and ±3% also available.
*2 B value determined by rated zero-power resistance at 25℃ and 85℃.
*3 Time necessary to reach 63.2% of temperature difference. Measured in still air.
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ET Thermistor Series (fast response time type)
The ET thermistor series is very small and features a very fast
response time.
- Small resistance and B-value tolerance; high accuracy
- Shape is unified, facilitating automatic assembly
- Long term reliability
Applications
Body thermometers, thermometers, medical devices, controllers,
mobile devices, battery packs, home electronics, toilet heaters,
security, LCDs, electric vehicles
、
*1 Rated zero-power resistance value at 25℃
*2 B-value determined by rated zero-power resistance at 25℃ and 85℃
*3 Time necessary to reach 63.2% of temperature difference. Measured in still air.
*1 Rated zero-power resistance value at 37℃
*2 B value determined by rated zero-power resistance at 30℃ and 45℃
*3 Time necessary to reach 63.2% of temperature difference. Measured in oil.
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HT Thermistor Series (high accuracy, surface mount type)
With the highly accurate HT thermistor series
re-flow soldering has become possible. The HT
thermistor series also features greatly improved
reliability compared to existing chip thermistors.
Applications
Office automation, communication devices, IT
devices, mobile devices, battery packs, LCDs,
hybrid ICs, AV devices, quartz crystal oscillators,
electric vehicles
Only for HTF:
TP = Taping
No denotation = Loose products
HT thermistor
*1 Rated zero-power resistance value at 25℃
*2 B value determined by rated zero-power resistance at 25℃ and 85℃
*3 Time necessary to reach 63.2% of temperature difference. Measured in still air.
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FT Thermistor Series (thin-film type)
FT thermistors have outclassed conventional thermistors
featuring quick response time, high heat resistance and
reliability through miniaturization.
Applications
Office automation, measurement instruments, medical
instruments, security, LCD, laser diode modules
□
1 = Pt
2 = Au/Ni
3 = Au
Tolerance (5P = ±5%)
B value (A = 3370k; B = 3435k)
Electrode type
＋
Dimensions (EIAJ)
FT thermistor
＋
Please contact us for custom-made FT thermistors.
*1: Rated zero-power resistance value at 25℃
*2: B value determined by rated zero-power resistance at 25℃ and 85℃
*3: Time necessary to reach 63.2% of temperature difference. Measured in still air.
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KT Thermistor Series (high accuracy, SMD chip type)
The KT thermistor series features high accuracy
(both resistance and B-value tolerance of ±1%).
This chip sensor is based on EIAJ standards
(dimensions: 1005, 1608) and highly reliable.
Applications
Office automation, communication devices, IT
devices, mobile devices, battery packs, LCDs,
hybrid ICs, AV devices
1P = ±1%
R25 Tolerance 2P = ±2%
3P = ±3%
Dimensions (EIAJ standard): Fig. 1
KT thermistor
Do not expose the thermistors to high
soldering heat for any longer than the
specified time. (We recommend no longer
than 10s at 260℃.)
Do not expose the thermistors to high soldering heat for any longer than the specified time. (We recommend no longer than 10s at 260℃.)
*1 Rated zero-power resistance value at 25℃
*2 B-value determined by rated zero-power resistance at 25℃ and 85℃
*3 Time necessary to reach 63.2% of temperature difference. Measured in still air.
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NT Thermistor Series (high temperature, high accuracy, glass-type)
Semitec's NT-4 thermistor series features high temperature
resistance and accuracy. Compared to conventional
thermistors the NT-4 series thermistors are smaller, quicker
and more reliable which makes them useful for many
different applications.
Applications
Heating/cooling devices, boilers, microwaves, domestic
appliances, hybrid cars, fuel cell cars, other car appliances,
medical, disaster prevention, security, office automation,
other high-temperature applications
Tolerance of B-value (G = 2%)
First two digits of B-value (e.g. 34 = B25/85 of 3435k)
Tolerance of rated zero-power resistance (H = 3%)
Base temperature of rated zero-power resistance
NT thermistor series
(Other resistance values are also available. Please contact us.)
*1 Rated power resistance at each temperature.
*2 B-value determined by rated zero-power resistance at each temperature.
*3 Time necessary to reach 63.2% of temperature difference. Measured in still air and oil (value in brackets).
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CT Thermistor Series (high temperature type)
Using a glass encased thermistor chip Semitec's
axial thermistor CT series features very high
reliability and temperature resistance.
Applications
Household electronics, heating / cooling devices,
boilers, kitchen equipment, solar systems, vending
machines, (cooled) product showcases, batteries,
refrigerators
To allow automatic assembly this product can be taped.
*1 Rated zero-power resistance value at 25℃
*2 B-value determined by rated zero-power resistance at 25℃ and 85℃
*3 Time necessary to reach 63.2% of temperature difference. Measured in still air.
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