To obtain low power consumption and long battery lifetime, a low-power three-axis accelerometer (U7) has been added to the remote control.
See Accelerometer circuit for the schematic. See also Intelligent power saving.
Figure 1. Accelerometer circuit
The accelerometer has I2C outputs and can detect motion on 3 axes. The sensitivity is configurable to ±2 g/±4 g/±8 g/±16 g.