[AK8975/C]
6. Functional Explanation
6.1. Power States
When VDD and VID are turned on from Vdd=OFF (0V) and Vid=OFF (0V), all registers in AK8975/C are
initialized by POR circuit and AK8975/C transits to Power-down mode.
All the states in the table below can be set, although the transition from state 2 to state 3 and the transition from
state 3 to state 2 are prohibited.
States VDD
VID
Power states
1
OFF (0V)
OFF (0V)
OFF (0V).
SCL, SDA should be fixed to the voltage that does
not exceed 3.6V. Other digital pins should be fixed
to L(0V).
2
3
OFF (0V)
2.4V to 3.6V
1.65V to 3.6V OFF (0V). It doesn’t affect external interface.
OFF (0V)
OFF (0V). It consumes current same as
Power-down mode.
SCL, SDA should be fixed to the voltage that does
not exceed 3.6V. Other digital pins should be fixed
to L (0V).
4
2.4V to 3.6V
1.65V to Vdd ON
Table 6.1
6.2. Reset Functions
AK8975/C has two types of reset;
(1) Power on reset (POR)
When Vdd reaches approximately 2V (reference value for design), POR circuit operates, and AK8975/C
is reset.
(2) VID monitor
When Vid is turned OFF (0V), AK8975/C is reset.
When AK8975/C is reset, all registers are initialized and AK8975/C transits to Power-down mode.
MS1187-E-02
- 11 -
2010/05
AKM [ ASAHI KASEI MICROSYSTEMS ]
