SFC4000 Ultra-Fast CMOSens® Mass Flow Controller for Gases SENSIRION TH SENSOR COMPANY - High accuracy Mass Flow Controller (0.8% of set point for 10 - 100% FS) - Ultra fast settling time (<100ms to within 2% of setpoint) - CMOSens technology - Analog interface (0-5Vdc) - Unipolar Power Supply (14 to 24 Vdc) - Down-mount, VCR, VCO fittings - Digitally calibrated & temperature compensated - NIST traceable calibration - Product I nformati on March 2009 - v25 CMOSens® SFC4000 Product Summary The CMOSens® SFC4000 mass flow controller enables the very fast and accurate control of gas flows over a very wide range. Its leading performance is based on Sensirion's unsurpassed CMOSens® sensor technology which combines a high precision sensor element with the amplification and A/D converter circuit on one single CMOS chip. The digital calibrated and temperature compensated sensor signal is converted directly on the CMOSens® chip into a PWM signal which is used in a fast analog controlling circuit to control the valve. This results in very high accuracy, fast settling time and large dynamic range. The CMOSens® sensor is packed in a vacuum tight stainless steel package which is mounted on a rugged aluminum housing. This makes the SFC4000 mass flow controller the best choice for a wide range of applications, such as mass flow controlling in process control, analytical instrumentation, medical applications, fuel cells, as well as gas flow metrology. The SFC4000 provides analog electrical interfaces for input and output signals (0- 5 V) and requires a standard supply voltage between 14 and 24 VDC. It can be operated at input pressures of up to 10 bar (145 psi). The SFC4000 is the result of intensive optimizations of the Sensirion PC1 mass flow controller. The new SFC4000 is highly compatible to the PC1 and offers even better specifications and a simpler power supply concept. www.sensirion.com Sensirion - the sensor company

CMOSens® SFC4000 Mass Flow Controller for Gases SeNSIRION TH StNSOR COMPANY Setpoint (0-5Vdc) Measured Mass Flow (0-5Vdc) Valve Controlled Mass Flow ) Input pressure P1 q (max. ambient pressure +10bar) Figure 1: Block Diagram CMOSens® SFC4000 Mass Flow Controller. Introductory Description The overall performance of a mass flow controller depends mainly on the mass flow sensor used in it. The heart of the SFC4000 Mass Flow Controller is powered by Sensirion's unsurpassed CMOSens® sensor technology. The SFC4000 Mass Flow Controller therefore provides very high performance and accuracy at very attractive...

Datasheet table.main {} tr.row {} td.cell {} div.block {} div.paragraph {} .font0 { font:5.00pt "Arial", sans-serif; } .font1 { font:6.00pt "Arial", sans-serif; } .font2 { font:8.00pt "Arial", sans-serif; } .font3 { font:9.00pt "Arial", sans-serif; } .font4 { font:10.50pt "Arial", sans-serif; } .font5 { font:11.00pt "Arial", sans-serif; } .font6 { font:22.50pt "Arial", sans-serif; } CMOSens® SFC4000 Mass Flow Controller for Gases SENSIRION th sensor company 1 CMOSens® SFC4000 Mass Flow Controller Performance Table 1: Overview of CMOSens® SFC4000 Mass Flow Controller Sp)cifications All data, unless...

CMOSens® SFC4000 Mass Flow Controller for Gases SENSIRION th sensor company 1.1 Accuracy Figure 2 compares the setpoint accuracy of a conventional mass flow controller with a CMOSens® SFC4000. Typically an accuracy of 1% FS (full scale) is stated for mass flow controllers using conventional sensor technology. The graph shows this in relation to the accuracy of the SFC4000 mass flow controller. It can be seen that especially at low flow rates the CMOSens® technology reaches superior performance. In Figure 3 the repeatability of the SFC4000 devices is compared with the repeatability of a typical...

CMOSens® SFC4000 Mass Flow Controller for Gases SENSIRION th sensor company 2 Working Principle of the CMOSens® Mass Flow Controller 2.1 Calorimetric Principle for Mass Flow Measurement The CMOSens® SFC4000 measures the mass gas flow using the calorimetric principle of measuring heat transfer. A heating element on a thermally insulated membrane is kept above ambient temperature. In the presence of gas flow, the temperature distribution up-and downstream is disturbed. This asymmetry is then measured. The whole arrangement is carried out on a silicon chip using CMOS standard processes. Due to the...

CMOSens® SFC4000 Mass Flow Controller for Gases SENSIRION th sensor company CMOSens® Chip Digital linearisation & temperature compensation Fast linearised and temperature compensated PWM signal for use in control loop - _n_nn_ raw data linearised & from the temperature flow sensor compensated signal EEPROM Calibration data stored on an external EEPROM Figure 6: Flow signal processing diagram of a typical CMOSens® mass flow sensor chip 2.4 Packaging principle and sealing To guarantee a vacuum proof housing of the sensor and the flow path, several patented technologies are used. The CMOSens® chip...

CMOSens® SFC4000 Mass Flow Controller for Gases SENSIRION th sensor company 2.5 Wetted Materials & Compatibility The packaging method ensures that a minimum number of inert materials only is wetted by the gas which is controlled by the SFC4000 MFC. The following Table 2 gives an overview of the materials wetted by the gas. Table 2: Overview of Wetted Materials ensure a tight and highly resistant sealing of the controller. Furthermore each controller is thoroughly leak tested during the manufacturing process. In addition the electronic circuit is designed in such a way that the maximum heating...

CMOSens® SFC4000 Mass Flow Controller for Gases SENSIRION th sensor company 3 Electrical Connection 3.1 Connector and Pin Layout The electrical connector of the SFC4000 is a standard Sub-D 9pin connector. This enables an easy and reliable universal connection. Please refer to the CMOSens® SFC4000 Installation Instruction Manual for the correct electrical connection diagram including instructions for grounding of the device. 3.2 Power supply The SFC4000 Mass Flow Controller requires a standard voltage supply of +14 to + 24 VDC. Since this voltage is internally regulated, there are no stringent...