There are two types of SMD’s (surface mount devices):
A platinum SMD (Pt100 or Pt1000) is a type of thin film RTD (resistance temperature detector). These have a positive temperature coefficient (PTC) meaning that the resistivity increases with an increase in temperature.
A NTC (negative temperature coefficient) SMD is a sensing element whose resistance decreases as temperature increases. Each SMD type has certain functions in common but also have unique attributes that can affect a customer’s choice.
|RTD SMD||NTC SMD|
|Most common choice in the process industry and especially for machine building. Suitable for protection from overcurrent and short circuit||Used for temperature measurement, control and compensation (eg signaling when a battery is fully charged).|
|Meets international standards.||Standardization for NTC elements is not possible as a result of material and specific production criteria.|
|Functions over a wider range of temperatures up to 200°C with thin film technology.||Very narrow temperature range:up to 125 °C.|
|Platinum is a more expensive material making the Pt SMD a more costly option. Thin film is reducing the price difference as less platinum is needed.||Cheaper and therefore more suited to applications where large volumes are required.|
|Better long term drift stability and is more accurate.||Has higher sensitivity and faster response time (however this is only the cae within a narrow temperature range).|
In conclusion, when choosing whether to use and NTC SMD or a RTD SMD element the following questions will ultimately determine your choice:
Our Yageo Nexensos Pt100 and Pt1000 SMD sensors are available in tolerance class B and 2B and in both simplex and duplex executions. There are four different sizes with a temperature range of -50°C to +150°C and a temperature coefficient of 3850 ppm. Furthermore, we offer the SMD 1206 SC which can be sintered instead of soldered which increases the temperature range to 200°C.