AK09912 Datasheet, PDF (14/42 Pages) HuaXinAn Electronics CO.,LTD – 3-axis Electronic Compass

6. Function Explanation
[AK09912]
6.1. Power States
When VDD and VID are turned on from Vdd=OFF (0V) and Vid=OFF (0V), all registers in AK09912 are initialized by
POR circuit and AK09912 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.
State
1
2
3
4
VDD
OFF (0V)
OFF (0V)
1.7V to 3.6V
1.7V to 3.6V
Table 6.1 Power state
VID
OFF (0V)
1.65V to 3.6V
OFF (0V)
1.65V to Vdd
Power state
OFF (0V).
It doesn’t affect external interface. Digital
input pins other than SCL and SDA pin
should be fixed to “L” (0V).
OFF (0V)
It doesn’t affect external interface.
OFF(0V)
It doesn’t affect external interface. Digital
input pins other than SCL and SDA pin
should be fixed to “L” (0V).
ON
6.2. Reset Functions
When the power state is ON, always keep Vid≤Vdd.
Power-on reset (POR) works until Vdd reaches to the operation effective voltage (about 1.1V: reference value for design)
on power-on sequence. After POR is deactivated, all registers are initialized and transits to power down mode.
When Vdd=1.7 to 3.6V, POR circuit and VID monitor circuit are active. When Vid=0V, AK09912 is in reset status and it
consumes the current of reset state (IDD5).
AK09912 has four types of reset;
(1) Power on reset (POR)
When Vdd rise is detected, POR circuit operates, and AK09912 is reset.
(2) VID monitor
When VID is turned OFF (0V), AK09912 is reset.
(3) Reset pin (RSTN)
AK09912 is reset by Reset pin. When Reset pin is not used, connect to VID.
(4) Soft reset
AK09912 is reset by setting SRST bit. When AK09912 is reset, all registers (without ASAX, ASAY and ASAZ) are
initialized and AK09912 transits to Power-down mode.
MS1547-E-02
- 14 -
2014/7