AK8963C Datasheet, PDF (18/38 Pages) Asahi Kasei Microsystems – 3-axis Electronic Compass

[AK8963]
6.4.3.6. Magnetic Sensor Overflow
AK8963 has the limitation for measurement range that the sum of absolute values of each axis should be
smaller than 4912μT.
|X|+|Y|+|Z| < 4912μT
When the magnetic field exceeded this limitation, data stored at measurement data are not correct. This is
called Magnetic Sensor Overflow.
When magnetic sensor overlow occurs, HOFL bit turns to “1”. When the next measurement starts, it returns to
“0”.
6.4.4. External Trigger Measurement Mode
When external trigger measurement mode (MODE[3:0]=“0100”) is set, AK8963 waits for trigger input. When
a pulse is input from TRG pin, sensor measurement is started on the rising edge of TRG pin. When sensor
measurement and signal processing is finished, measurement data is stored to measurement data registers
(HXL to HZH) and all circuits except for the minimum circuit required for trigger input waiting are turned off
(PD state). When the next pulse is input, AK8963 wakes up automatically from PD and starts measurement
again.
External trigger measurement mode ends when power-down mode (MODE[3:0]=“0000”) is set. AK8963
keeps waiting for the trigger input until the power-down mode is set.
When external trigger measurement mode (MODE[3:0]=“0100”) is set again while AK8963 is already in
external trigger measurement mode, it starts to wait for the trigger input again. The trigger input is ignored
while sensor is measuring.
Data read sequence and functions of read-only registers in external trigger measurement mode is the same as
continuous measurement mode.
MS1356-E-02
- 18 -
2013/10