AK7401 Datasheet, PDF (9/29 Pages) Asahi Kasei Microsystems – Rotary Position Sensor IC

[AK7401]
14. Programmable Mode Descriptions
The AK7401 has the two operating modes (Normal Mode and User Mode). In User Mode, it is able to
read and write the internal registers and EEPROM according to a serial I/F. User Mode supports the
end-user programming such as zero point adjustment, magnet rotation direction, angle data averaging,
PWM frequency, PWM polarity and PWM output type.
When the power supply is turned ON, the AK7401 automatically resets the internal register and loads the
EEPROM configuration data to set the internal configuration register. After startup sequence, the
AK7401 operates in Normal Mode.
● Mode Description
Each mode can be changed by writing a specific OPCODE and DATA on a specific address as the
diagram below.
Normal Mode
ChangeMode
OPCODE: 0101
Addr. 0x02
DATA: 0x50F
User Mode
ChangeMode
OPCODE: 0101
Addr. 0x02
DATA: 0x000
or
Restore power supply
or
Reset
OPCODE: 0110
Addr. 0x4E
Figure 6. Operation Mode Transition Diagram
Mode Name
Normal Mode
Table 3. Operation Mode Description
Note
In Normal Mode, it is not able to access the internal register and EEPROM except
register R_ANG (Addr.0x00) and register R_CHMD (Addr.0x02). Available operation
codes are ReadAngle and ChangeMode.
The transmission time interval of ReadAngle operation code needs to be equal to
angle data update period or longer. If the interval time is shorter, R_ANG register is
not updated to the latest processing data.
In case of changing operation mode from User Mode to Normal Mode, all registers
are automatically initialized and loads the EEPROM configuration data to set the
internal configuration register.
014002685-E-01
-9-
2015/07