Contents

AN4348

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DocID025166 Rev 1

Contents

1

How does an electrochemical gas sensor work?.......................... 3

2

Signal conditioning with a three-electrode sensor ....................... 5

3

Signal conditioning with a two-electrode sensor .......................... 6

4

Integrator configuration ................................................................... 7

5

Constraints of gas sensor on the design of an application ......... 8

6

From sensor specification to functional application .................... 9

7

Consumption considerations ........................................................ 10

8

Galvanic configuration................................................................... 11

9

Other op-amp parameters to consider ......................................... 13

10

Filtering ........................................................................................... 15

11

Maintaining the sensor biased ...................................................... 17

12

Cross-sensitivity, environmental variation, and long-term

output drift ...................................................................................... 19

13

Layout recommendations .............................................................. 20

14

Testing the hardware ..................................................................... 21

15

Conclusion ...................................................................................... 22

16

Revision history.............................................................................. 24