Specifications

Data sheet

BMA220

Page 33

BST-BMA220-DS003-08 | Revision 1.15 | August 2011 Bosch Sensortec

third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany.

Note: Specifications within this document are subject to change without notice.

6.1 Dedicated Modes (μC-less / stand alone)

After reset (POR, soft-reset or reset pin) the system monitors the pin PS (Protocol Select). If the

pin is unconnected, an internal module detects the floating state and enables one of the

dedicated modes depending on the other select pins (SCK, INT).

There are three different dedicated modes:

 Orientation detection mode: only orientation interrupt detection is enabled.

 Tap/double-tap detection mode: only tap sensing interrupt detection is enabled.

 Wake-up detection mode: only wake-up interrupt detection is enabled.

In dedicated mode, the interrupt engine uses default settings for all configuration registers.

Those default settings are loaded after reset and are listed in section 5. Changing the default

configuration of the registers is not possible while the chip is in the dedicated mode.

Currently, in orientation and wake-up mode, the user can select between two different sleep

durations via the CSB pin:

Table 17: Sleep durations for dedicated modes

Dedicated Mode CSB Sleep duration

0 100ms Dedicated

orientation

1 1s

0 10ms

Dedicated wake-up

1 500ms

0 No sleep Dedicated tap-

sensing

1 2ms

Table 18: Filter bandwidths for dedicated modes

Dedicated Mode Bandwidth

Dedicated orientation 32Hz

Dedicated wake-up 16Hz

Dedicated tap-sensing 1kHz