What is a NTC 100KΩ sensor ?
The NTC 100 kΩ is a thermistor with a high nominal resistance (100,000 Ω at 25 °C).
It is the current standard for modern precision sensors: high stability, low power consumption, and excellent sensitivity between 0 and 80 °C.
Its very high impedance makes it ideal for high-impedance analog input microcontrollers, such as ESP32, STM32, Arduino, or industrial measurement boards.
Operating principle
Like all NTCs, its resistance decreases with temperature according to the exponential law:
R(T) = R₂₅ × e^{β (1/T - 1/T₂₅)}
where:
- R₂₅ = 100000 Ω
- β ≈ 3900 K
- T in kelvins
- The equation can be linearized using the β formula or Steinhart–Hart for high-precision measurements.
Technical Specifications
| Parameter |
Typical value |
Nominal resistance (25 °C) |
100 000 Ω ±1 % |
| Constant β | 3435–3900 K |
Sensitive material | Metallic oxide (Mn, Ni, Co) |
| Type of case | Epoxy / glass / film |
Maximum measurement current | 0.03 to 0.05 mA |
Response time | 0.2 to 0.8 s |
Linearity | Exponential |
Operating temperature | −55 → +150 °C |
Lifetime | 100,000 thermal cycles |
Wiring Configuration
Classically set up in a voltage divider, the NTC 100 kΩ is read through an analog ADC input of the microcontroller.
+Vcc │ [Rfixe] │────► ADC (µC) [NTC 100kΩ] │ GND
Self-warming
Thanks to a nearly zero current, the dissipation remains below 0.01 °C/mW, ensuring excellent accuracy without thermal correction.
Application areas
🧠 Industrial and Environmental Probes
🧱 HVAC, Home Automation, and Smart Thermostats
🩺 Medical Sensors, Thermometers, Incubators
🔋 Embedded Electronics and IoT
⚙️ 3D Printers and Precise Thermal Control