Temperature Sensor Thermistors

Thermistors are temperature-sensitive resistors that change their resistance in response to temperature variations. The commonly used thermistors can be divided into two types: Negative Temperature Coefficient (NTC) and Resistance Temperature Detector (RTD).

Negative Temperature Coefficient (NTC) Thermistors:

Working Principle: NTC thermistors have a resistance that decreases as temperature increases. This means their resistance is inversely proportional to temperature. As the temperature rises, the resistance of NTC thermistors decreases.

Materials: NTC thermistors are typically made of oxides or semiconductor materials such as zinc oxide or nickel oxide. These materials are highly sensitive to temperature changes.

Response Time: NTC thermistors exhibit relatively fast response times, making them suitable for applications requiring rapid measurement and response.

Applications: Due to their fast response and sensitivity, NTC thermistors are commonly used for temperature measurement and control, such as in automotive engine temperature monitoring, household appliances, and electronic devices.

Resistance Temperature Detector (RTD) Thermistors:

Working Principle: RTDs have a resistance that increases with temperature, meaning their resistance is directly proportional to temperature. As the temperature rises, the resistance of RTDs increases.

Materials: RTDs are typically made of stable materials like platinum, which exhibit a high temperature coefficient of resistance and excellent linearity.

Accuracy: RTDs generally offer higher accuracy and stability, especially over a wider temperature range.

Applications: Due to their high accuracy and stability, RTDs are commonly used in applications requiring precise temperature measurement, such as laboratory measurements, industrial processing, and medical equipment.

While both NTC thermistors and RTDs are temperature sensors, they differ in their working principles, materials, and applications. RTDs offer higher accuracy compared to NTCs, but RTDs are also much more expensive than NTCs.