AK7451 Datasheet, PDF (28/32 Pages) Asahi Kasei Microsystems – zero latency angle sensor ic

[AK7451]
18. Abnormal Detection Functions
This IC detects an abnormal state and indicates an abnormal state via ERROR PIN and serial interface.
Abnormal state is outputted at the angle output timing after 2.7ms(Typ) delay after detecting abnormal
state.
1) Abnormal Detection Items
●Magnetic Flux Density Range Error
When IC is applied in less than 10mT(Typ), the abnormal state is detected.
●Tracking Lost
If the angle error in the tracking by the type 2 servo is greater than or equal to 2°, it will be tracking
lost state (if the lock state is out due to type 2 servo). Because it is not overlooking the accurate
absolute angle output in this state, it will be the anomaly detection state. Also monitoring of the
abnormal state is every 2.56ms (Typ).
2) Output state in abnormal
The output is as following during abnormal state.
・ABZ and UVW Output
ABZ and UVW signal is outputted even if during abnormal state but the data may not be correct.
・SPI Output
The parity bits(P1 and P2 bit) and error bit is outputted as following.
Normal State
Abnormal State
P1 bit
ODD parity
EVEN parity
P2 bit
ODD parity
EVEN parity
E bit
1
0
・ERROR PIN Output
Output is low in abnormal state (high in normal state). The updating cycle of Error pin output is
every 80µs(Typ.).
Note 20. When the abnormal state is released, IC returns to the normal output state automatically.
Note 21. In User mode, output on ERROR PIN is low state.
016006637-E-00
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2016/05