AK8998 Datasheet, PDF (8/59 Pages) Asahi Kasei Microsystems – Preliminary

[AK8998/W/D]
Block
Timing
Logic
Regulator
Pressure
Detector1, 2
Functions
Generates timing sync signals for internal operation and sampling frequencies for
sensor output signals. Sampling frequency (fs): 10kHz or 1kHz
Constant voltage generator circuit to drive the sensor. The drive voltage can be
selected from the EEPROM depending on the supply voltage being used.
Drive voltage: 2.2V @VDD:3, 3.3V±5%, 4.0/2.2V @VDD:5V±5%
Two sets of pressure detection circuits.
The pressure range can be individually selected depending on the EEPROM data for the
pressure detector.
• Pressure above a certain value is detected
• Pressure below a certain value is detected
The DET1 and DET2/PTH pins go high when the detected pressure exceeds the
threshold (the polarity change by EEPROM is possible). The detection threshold can be
set by the input of DET2/PTH pin (when only pressure detector 1 is used) or using the
EEPROM data in the AK8998. The hysteresis voltage can be adjusted at 2 bits (4 steps),
and it varies ratiometrically with respect to the supply voltage as well as the detection
threshold.
Note that the exact pressure determination cannot be achieved until the VOUT pin output
is stabilized at the time of power up or due to the above setup and buffer circuit feedback
resistor and external capacitor values.
MSxxxxx-E-00
-8-
2012/11