FS1.0.1L.195 (IST INNOVATIVE SENSOR TECHNOLOGY)

The FS1.0.1L.195 from IST Innovative Sensor Technology is a thermal mass flow sensor for gas flow applications. The flow sensor element consists of two temperature depending platinum resistors deposited on one chip. The low ohm resistor with a small area is used as a heater, whereas the other high ohm resistor serves to measure the reference temperature. Using a bridge circuit, the differing resistance value of two elements leads to different (self) heating. The (self) heating is dependent upon the applied voltage, the mass flow and the media in which the sensor is located. Higher voltage increases self heating, a higher flow rate increases cooling. If the self heating is kept constantly by a suitable controller, the voltage increases with higher flow rates and therefore becomes a measure for the mass flow. As a result of this little thermal mass, this sensor has fast heating and cooling response times.