AK8999AW Datasheet, PDF (9/68 Pages) Asahi Kasei Microsystems – Pressure Sensor Control IC

CONFIDENTIAL
[AK8999A/AW/AD]
Reference Section & Others
Block
Functions
Generates the reference voltage or bias current required for each circuit.
V_Bandgap The VREF voltage is adjusted to 1.0V.
(VBG)
VREF voltage adj.
Resolution
3bits
V_Reference
Adj. step
1% / step
(VREF)
IREF current is adjusted to 1.0V, in state of connecting 1MΩ external resistor to VOUT
I_Reference pin.
(IREF)
IREF current adj.
Resolution
4bits
Adj. step
2.8% / step
Oscillator to generate timing sync signals for internal operation and sampling
frequencies. Oscillation frequency is adjusted as the counter result reaches the expected
Oscillator value, the internal counter counts for the period of CSCLK is high (2msec typ.). For the
(OSC)
detail, refer to the Functional Descriptions 1) Adjustment Procedure Description (Example).
OSC adj.
Resolution
4bits
Adj. step
5% / step
Temperature sensor converting the ambient temperature to voltage. Adjust the
temperature sensor output voltage so that it is equal to VREF voltage at 25ºC.And it is
also possible to select the external temperature sensor by EEPROM in the case where a
pressure sensor and the AK8999A are separated physically. When the external
V_temp. temperature sensor is chosen, it is driven by 50uA constant current which is sunk or
(VTMP) sourced from the EXTMP pin.
VTMP voltage adj.(internal) Resolution
6bits
Adj. step
0.2% / step
VTMP voltage adj.(external) Resolution
9bits (Coarse /Fine=3/6bits)
Adj. step
Coarse 10% /step / Fine 0.2% /step
V_Common
(VCOM)
Generates analog circuit reference voltage 0.5*VDD.
The internal power-up circuit causes it to start up within the settling time for stable
analog operation.
Power Up circuit is for stable analog operation upon power-up.
Power ON
In order to make the power-on reset effective, be sure to power up the supply voltage
Reset(POR)
from below 0.1*VDD.
Serial I/F
Serial interface for accessing EEPROM and control register (volatile memory).
It accesses using the CSCLK pin and the VOUT pin.
EEPROM & EEPROM and control register (volatile memory).
Control Used to store compensation values and measurement modes and to set up the
Register measurement modes for adjustment.
MS1600-E-00
-9-
2014/05