AN4368

Consumption

DocID025334 Rev 1

9/18

4

Consumption

Consumption is a key feature for portable applications. The schematics in Section 3:

"Three-stage architecture for detecting motion" have been designed to optimize

consumption and to be 3.3 V compatible, especially with regard to microcontrollers.

The main consumption is due to the sensor which consumes 19 µA. The rest of the

application consumes 4.8 µA as follows:

a TSU104 op-amp consumes 2.4 µA

The consumption of the divider bridge could be reduced by multiplying the resistor values

but at the cost of reliability. When impedances are high, the impact of dust or moisture is

higher. These perturbations can create parasitic impedances.