The ASLF-25 liquid flow sensors are based on the micro-machining and packaging technology. The sensor is comprised of one micro heating and two thermal sensing elements positioned symmetrically up- and down-stream of the heater. The thermal sensing elements are capable of detecting thermal flow profile asymmetry due to fluid flow and thus this method allows for velocity measurements at different flow rates. MEMS technology to create the micro heater and thermal sensors simplifies the fabrication and operational design requirements. This flow sensor can be used with a valve or pump coupled with electronics to precisely control fluid flows.

Key Features

Measurable flow rates up to 25 mL/min for water-based solutions
High accuracy of ±2.5% reading
Wide dynamic range with the turn-down ratio of 100:1
Excellent reliability
Package enclosure made of polycarbonate (PC)
Low power consumption
High sensitivity to low flow rates
Bidirectional measurement option

Typical Applications

Medical drug delivery and administration, e.g. anesthesia, intravenous injection etc.
Biomedical analytical instruments for flow management in liquid chromatography, mass spectrometer, and flow cytometers
Semiconductor industry for plasma etching processes, and thin film deposition
Fuel consumption monitoring

Model	ASLF-25
Full Scale Flow	±10, ±15, ±20, ±25 mL/min, or customer specified
Turndown Ratio	100:1
Accuracy	±2.5% reading or ±0.15% FS whichever is greater
Reproducibility	±0.5%
Offset Stability	±0.1% Full Span (FS)
Power Supply	3.6 – 6.0 VDC
Power Consumption	60 mW
Current Draw	12 mA
Response Time	40 ms
Output	Analog; Digital with I²C
Maximum Pressure	0.5 MPa
Operating Temperature	5 – 50 °C
Pins Out	5 pins (2.54 mm centers, 0.635 mm square)
Calibration	Using distilled water at 20 °C and 1 atm
Packaging Material	Medical grade Polycarbonate (PC)
Dimensions	62 x 52 x 12.8 mm
Weight	15 g
Storage Temperature	-10 ~ +60 °C, but avoid icing inside