LIS25BA datasheet(23/32 Pages) STMICROELECTRONICS

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LIS25BA

Features

6.1

Self-test mode

In self-test mode the mechanical element is stimulated by electrostatic force to obtain an

equivalent input force applied to the sensor. This equivalent input force applied has to be

comparable with the full-scale range in order to have an effective self-test mode.

The self-test mode can be enabled using the I²C interface, setting the ST bit in register

TEST_REG (0Bh) to ‘1’.

For the self-test values of each axis please refer to Table 3: Mechanical characteristics.

6.2

Power cycle/reset information

6.2.1

TDM interface power-on sequence

In TDM, the LIS25BA starts in disabled mode with the following sequence.

Figure 13. Power-on sequence (TDM interface)

In Figure 13 T0 represents the time when Vdd reaches 90% of the final value.

After TDIS = 5.5 ms the LIS25BA reaches the disabled mode condition.

The TDM interface must be activated explicitly with I²C configuration. The first 3 samples

after the enabling of the TDM may be invalid samples due to the fact that the interface

should sync on the external WCLK. The samples will be invalid also after any subsequent

Disable-Enable transition that may happen. TDM protocol can be changed on the fly, but

also in this case the first 3 samples after the TDM configuration change will be invalid.

LIS25BA Datasheet(PDF) 23 Page - STMicroelectronics