AK8998 Datasheet, PDF (55/59 Pages) Asahi Kasei Microsystems – Preliminary

[AK8998/W/D]
6.2) Description of Control Register (Volatile Memory)
a) Adjustment mode (Register name: CM1)
This register is used to adjust the AK8998 reference voltage and pressure sensor's offset,
span, offset temperature drift and sensitivity temperature drift including those of the AK8998.
In addition, the value of the register returns to the initial value on the following conditions.
■ At the power up
■ When CSCLK=Low is maintained 0.5msec or more
■ When ETST[0] is set to "L"
Address : 00 hex D[3:0]=AM[3:0]
(This is not a nonvolatile EEPROM, but a volatile register.)
D[7:0] Symbol
Mode setup
Description
D[7:4]
Reserved
D[3:0] AM[3:0] IC adjustment mode
0000
(default)
0001
0010
AVR
AIR
VREF adjustment The VREF voltage is output at the VOUT pin.
IREF adjustment The IREF current is output at the VOUT pin.
0011 AFR
OSC adjustment
Input the fixed period of High level (2.0msec) from
the CSCLK pin. The count value in the internal
counter is stored in the register.
0100 ATO
The VTMP voltage is output at the VOUT pin.
VTMP adjustment Adjust this voltage so that it matches the VREF
0101 ADT1
judge threshold 1
adjustment
voltage at 25°C.
The internally set judge threshold value 1 is output
at the VOUT pin.
0110 ADT2
judge threshold 2 The internally set judge threshold value 2 is output
adjustment
at the VOUT pin.
0111 AHY1
hysteresis voltage 1
The hysteresis voltage of the comparator 1 is
output at the VOUT pin.
1000 AHY2
hysteresis voltage 2
The hysteresis voltage of the comparator 2 is
output at the VOUT pin.
1001-
1111
Reserved
MSxxxxx-E-00
- 52 -
2011/12