Application information

TSX711, TSX711A, TSX712

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DocID025959 Rev 5

5.11

Application examples

5.11.1

Oxygen sensor

The electrochemical sensor creates a current proportional to the concentration of the gas

being measured. This current is converted into voltage thanks to R resistance. This voltage

is then amplified by the TSX711, TSX711A, or the TSX712 (see Figure 36: "Oxygen sensor

principle schematic").

Figure 36: Oxygen sensor principle schematic

The output voltage is calculated using Equation 8:

Equation 8

become significant with a traditional operational amplifier. The use of a precision amplifier

like the TSX711, TSX711A, TSX712 is perfect for this application.

In addition, using the TSX711, TSX711A, TSX712 for the O2 sensor application ensures

that the measurement of O2 concentration is stable, even at different temperatures, thanks

-

+

+

-

O2_ sensor

R1

R2

VCC

Vout

I

V

ou t

I

R

V

io

R

2

R

1

1

+

×

–

×

=