Datasheet

BMM150 Geomagnetic Sensor

Page 11

BST-BMM150-DS001-01 | Revision 1.0 | April 2013

Bosch Sensortec

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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. Functional description

BMM150 is a triaxial standalone geomagnetic sensor (Sensing element and ASIC) in chip scale

wafer level package and can be operated via I2C or SPI as a slave device.

4.1 Power management

The BMM150 has two distinct power supply pins:

digital logic.

0V) or vice versa.

& CSB] ≠ high).

The device contains a power on reset (POR) generator. It resets the logic part and the register

specific settings which are not equal to the default settings (refer to register maps in chapter

5.2), must be re-set to its designated values after POR.

pin is recommended in order to ensure reliable protocol selection.

4.2 Power modes

The BMM150 features configurable power modes. The BMM150 magnetometer part has four

power modes:In the following chapters, power modes are described.

4.2.1 Power off mode

4.2.2 Suspend mode

initialized. After POR becomes inactive, a start up sequence is executed. In this sequence NVM

content is downloaded to shadow registers located in the device core. After the start up

sequence the device is put in the Suspend mode. In this mode only registers which store power

control bit information and SPI3 wire enable can be accessed by the user. No other registers

can be accessed in Suspend mode. All registers lose their content, except the control register

(0x4B). In particular, in this mode a Chip ID read (register 0x40) returns “0x00” (I²C) or high-Z

(SPI).