AK7401 Datasheet, PDF (14/29 Pages) Asahi Kasei Microsystems – Rotary Position Sensor IC

[AK7401]
● Averaging Data range Diagnostic Function
The AK7401 indicates an error when the original data set before averaging spread out among three
quadrants. This error sets the PWM output level to low and error bit to “0”.
It is caused by higher rotation speed than averaging time.
Quadrant 2
2
Quadrant 3
Quadrant 1
1
Quadrant 2
4
5
6
Quadrant 4
7
Quadrant 3 ⁸
Quadrant 1
3
2
1
Quadrant 4
(a) In Case of Moving Average Filter SPC
(b) In Case of Moving Average Filter HP
Figure 8. Example of Error Diagnosis for Spreading Data Set
Quadrant2
2
Quadrant1
1
Quadrant2
5
6
7
8
Quadrant1
4
3
2
1
Quadrant3
Quadrant4
Quadrant3
Quadrant4
(a) In Case of Moving Average Filter SPC
(b) In Case of Moving Average Filter HP
Figure 9. Example of No-error Diagnosis for Spreading Data Set
014002685-E-01
- 14 -
2015/07