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Data sheet

BMA220

Page 12

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.

4.1.5 Soft-reset

The BMA220 can be put into a soft-reset state by performing a read from the soft-reset address.

To bring the chip back into operation, another read must be performed from the same memory

address. The reading returns value 0xFF if the system was in soft reset mode; otherwise it

returns value 0x00.

Please note that all internal configuration data programmed by the user will be lost.

4.1.6 Suspend mode

The BMA220 can be put into a suspend mode e.g. to easily achieve a power consumption

below 1μA by performing a read from the suspend address. To bring the chip back into normal

mode operation, another read must be performed from the same memory address. The reading

returns value 0xFF if the system was in suspend mode, otherwise it returns value 0x00.

Please note, that during suspend, all analog modules expect for power-on-reset will be disabled.

Only reads through the serial interface are supported during suspend.

4.2 Setting registers

4.2.1 Acceleration range and sensitivity setting

The BMA220 has four different range settings for the full scale acceleration range. In

dependence of the use case always the lowest full scale range with the maximum resolution

should be selected. Please refer to literature to find out, which full scale acceleration range,

which sensitivity or which resolution is the ideal one.

This can be configured via the register bits

range[1:0] at address 0x11 (SPI) / 0x22 (SPI).

The following table shows the range bits with corresponding scale and resolution.

Table 5: Acceleration resolution

range[1:0] Full Scale Sensitivity Resolution Example use case

‘00’ ±2g 16 LSB / g 62.5mg / LSB

Orientation

recognition

‘01’ ±4g 8 LSB / g 125mg / LSB

‘10’ ±8g 4 LSB / g 0.25g / LSB

Gaming

‘11’ ±16g 2 LSB / g 0.5g / LSB

Shock vibration

detection

1 2 ... 7 8 9 10 11 12 13 14 15 16 17 ... 62 63

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Bosch MAN-REG-X-08 Spezifikationen Seite 12