SRT3100 Pressure Sensors: Full-Range Temp Compensation

The SRT3100 series pressure sensors are an OEM line from Beijing SRT Sensor Technology Co., Ltd., based on the silicon piezoresistive effect. These diffused silicon pressure sensors use the piezoresistive properties of silicon to provide stable, repeatable pressure measurements.

Design and Temperature Compensation

The SRT3100 series uses a dual inline package (DIP) that mounts a temperature-compensated micro differential pressure sensing die together with a ceramic base and thick-film resistors on a PCB substrate. Although semiconductor devices are sensitive to temperature, these sensors integrate thick-film thermistors on the ceramic base to provide compensation across the full temperature range, reducing performance drift caused by temperature changes. During manufacturing, laser trimming is used to precisely calibrate the thick-film thermistors to ensure accurate sensor zero and temperature compensation zero points.

Measurement Ranges and Types

The pressure measurement range covers 10 mbar to 7 bar (1 kPa to 700 kPa), with both high-sensitivity low-range and high-pressure high-range models available to meet different application requirements. For example, low-range models are suitable for precision sensing such as ventilator occlusion detection, while high-range models are suitable for liquid flow measurement and level monitoring in higher-pressure environments. In the product naming, "D" indicates differential type, capable of measuring positive and negative pressure changes (for example, SRT3100-070M-D-S has a range of ±70 mbar); "G" indicates gauge type, supporting positive pressure measurement only (for example, SRT3100-150M-G-S has a range of 150 mbar).

Figure 2 SRT3100 pressure sensor reference circuit

Environmental and Packaging

The operating temperature range is -40°C to +85°C. The temperature compensation range is -10°C to 60°C, within which the device maintains improved temperature stability. The device can operate outside the compensation range, but compensation effectiveness may be reduced, so use within the specified temperature range is recommended. The dual DIP package facilitates integration and selection.