1. Victor Li,E-mail:victor2288@126.com, MP:13818224729, website: http://www.ist-ag.com INNOVATIVE SENSOR TECHNOLOGY Flow Sensors

2. www.ist-ag.com Background Traditional IST Products: Temperature Thin Film Sensors Flow Sens = more than 1 T-Sensor on 1 Chip 

3. www.ist-ag.com Working Principal Cooling of a heated resistance. The higher the flow, the better the cooling. - Heat transfer coefficient sensor-medium is dependent on flow velocity - The higher the flow, the more molecules passing the sensor, carrying away the heat. Flow Sensor Heat transfer  flow

4. www.ist-ag.com FS1 Family Layout R heater R sensor Common 7mm 2.4mm 2 Elements on 1 Chip: - 1 current heated (45 Ohm @ 0°C) - 1 reference element (1200 Ohm @ 0°C)

5. www.ist-ag.com FS1 Family Advantages Gases FS1 / FS1A Liquids FS1L / FS1LA - Large operation range - easy to build in - insensitive to contamination - no mechanical moving parts - high chemical resistance

6. www.ist-ag.com FS1 Family Applications - extraction systems - compressed air control - HVAC - dosage of gases - cooling circuit controls - heating systems - pump controls - food industry Gases FS1 / FS1A Liquids FS1L / FS1LA

7. www.ist-ag.com FS1 Family Evaluation R S R 1 R H V1 V2 R 2 R 3 V U_Bs GND Sensor Control of U_Bs  dT = const. dT = Temperature difference T(R H ) – T(R S ) To ensure constant dT, V1-V2 is controlled to 0. R1 is necessary to compensate the temperature difference  U_Bs = proportional to the mass flow

8. www.ist-ag.com FS1 Family Output signal Gas flow up to 100m/s (const. dT=30K, Channel  2mm, G=100) Gas flow laminar (const. dT=30K, Channel  4mm, G=100)

9. www.ist-ag.com FS1 Family Detecting air bubbles

10. www.ist-ag.com FS1 Family Test Kit  4 Sensors: 2 FS1 and 2 FS1A or 2 FS1L and 2 FS1LA  Electronic (Housing 80x80x35mm)  RS232 cable  Power supply 15V  Software (CD) Start up Kit for flow measuring technology with FS1-Family - Analogue output - Serial interface

11. www.ist-ag.com FS2 Family Layout 3 or 4 elements on 1 Chip: - 1 current heated (25 Ohm @ 0°C) - 2 measuring elements (250 Ohm @ 0°C) - FS2T: 1 reference element (550 Ohm @ 0°C)

12. www.ist-ag.com FS2 Family Applications: - differential pressure sensors - filter monitoring - over pressure cleanroom - directional switch Advantages: - very small flow <1m/s - detect direction - FS2T with additional T-Sensor for higher flow

13. www.ist-ag.com FS2 Family Evaluation FS2 : VCC = const. V Heater = const.  V1-V2 proportional to the mass flow incl. detection of flow direction  for small mass flows only FS2 T: Control V Heater - R Ref const dT According to evaluation FS1  U Bs proportional to the mass flow  V1-V2 detection of flow direction R S left R1R1 R S right V1V2 R2R2 V VCC GND

14. www.ist-ag.com FS2 Family Output signal air flow direction small air flow

15. www.ist-ag.com microflowSens TM System - 4 resistive elements on one Chip (full bridge) - Measuring elements on organic membrane - Glass carrier results in a robust system and easy handling - Positioning holes allow positioning + electrical connection

16. www.ist-ag.com microflowSens TM Advantages - Fast response time (<10ms) - Measuring of small mass flows - Detection of direction - Simple electronical analysis - Best price - performance ratio

17. www.ist-ag.com microflowSens TM Applications - Differential pressure sensors - Medical devices (e.g. artificial respiration) - HVAC and building control solutions

18. www.ist-ag.com microflowSens TM Evaluation VCC = constant (approx. 5V)  V1-V2 proportional to mass flow incl. detection of direction  just for small mass flows suitable

19. www.ist-ag.com microflowSens TM Evaluation Typical Characteristic ± 0.8 m/s