Datasheet

BMM150 Geomagnetic Sensor

Page 18

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

Bosch Sensortec

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

4.6.1 General features

An interrupt is cleared depending on the selected interrupt mode, which is common to all

interrupts. There are two different interrupt modes: non-latched and latched. All interrupts

(except Data Ready) can be latched or non-latched. Data Ready (DRDY) is always cleared after

readout of data registers ends.

A non-latched interrupt will be cleared on a new measurement when the interrupt condition is

not valid anymore, whereas a latched interrupt will stay high until the interrupts status register

(0x4A) is read out. After reading the interrupt status, both the interrupt status bits and the

interrupt pin are reset. The mode is selected by the “Interrupt latch” bit (register 0x4A bit1),

where the default setting of “1” means latched. Figure 4 shows the difference between the

modes for the example Low-Threshold interrupt.

INT and DRDY pin polarity can be changed by the “Interrupt polarity” bit (register 0x4E bit0) and

“DR polarity” (register 0x4E bit2), from the default high active (“1”) to low active (“0”).

Figure 4: Interrupt latched and non-latched mode

4.6.2 Electrical behavior of magnetic interrupt pins

Both interrupt pins INT and DRDY are push/pull when the corresponding interrupt pin enable bit

is set, and are floating (High-Z) when the corresponding interrupt pin enable bit is disabled

(default).

Low threshold

measurements

INT pin (non-latched)

INT pin (latched)

Readings of interrupt status register (0x4A)

a

a