Name: MEMS technology core chip-level hot film micro flow detection flow sensor AFE-01

Brand: SST

The AFE-01 consists of four platinum film resistors. Low impedance, small heating area. A high impedance resistor on the left and right sides of the heater is used to detect the flow rate and direction. There is also a resistor to detect the temperature of the gas. The two resistors adjacent to the heating element are connected to form a bridge. An output signal for the function of detecting flow rate and flow direction is generated. In the absence of flow, the two resistors reach the same heating state. When there is flow, the temperature of one of the resistors is much lower than the other, and the specific resistance temperature becomes lower is determined by the flow direction. The temperature difference can be measured and is determined by the flow rate and direction. The heating time and response time of the flow sensor is very short because of its small thermal mass. This way very small changes in flow rate can be detected. In order to obtain higher flow rates, the temperature sensor can be connected to a thermostatic anemometer.

Advantage

1. Flow direction detection

2. Detect the flow of small mass objects

3. Simple signal processing circuit and calibration

4. Fully fixed mechanical elements

5. Excellent repeatability

6. Excellent long-term stability

7, suitable for a variety of industries or installed to different housings

8. Excellent cost performance

Application

1. Differential pressure sensor

2, HVAC and Building Control Solutions

3, Medical Equipment

4. The automotive industry

5. Equipment detection

Technical indicators

Measuring principle: heat principle

Detection range: 0 ... 50 m/s (take the circuit of CTA mode as an example)

Sensitivity: 0.001 m/s

Accuracy:< 2% of measured value (depending on circuit and calibration)

Response time: T63% < 0.5 S

Temperature range:-20... 150°C

Electrical connection: insulated enameled copper wire (general length 25mm)

Heating element: RH (25°C) = 34 □ ± 10%

Detection element: Rs_ I (25°C) = 425 □ ± 10%

Reference element: RR (25°C) = 710 □ ± 10%

Supply voltage: generally 2... 5 V (depending on gas flow rate)

Substrate material: low thermal conductivity ceramic