AK8973 Datasheet, PDF (6/31 Pages) Asahi Kasei Microsystems – 3-axis Electronic Compass

ASAHI KASEI
[AK8973]
4.2. Block Function
Block
HE-X, Y, Z
MUX
Chopper SW
HE-Drive
Pre-AMP
DAC
Integrator
S&H
ADC
T-sensor
OSC
Interface Logic
& Register
Timing Logic
EEPROM
Function
High sensitivity sensors included in the package
Multiplexer for selecting one axis from the 3-axis magnetic sensor
Performs chopping.
Magnetic sensor drive circuit for constant-current driving of sensor
Variable-gain differential amplifier used to amplify a magnetic sensor signal and to adjust
sensitivity.
Gain setting: 26.8dB min., increased in 0.4dB/step, 16 steps (4 bits)
DAC for offset voltage compensation.
Resolution: 8 bits
Integrates and amplifies the Pre-AMP output signal.
Sample-and-hold circuit
Performs analog-to-digital conversion for the signal of each sensor.
Resolution: 8 bits
Temperature sensor:
Outputs the voltage proportional to the temperature.
Built-in oscillator
Automatically oscillates the operation clock in the sensor measurement mode.
Exchanges data with the external CPU.
I²C bus interface using two pins, namely, SCL and SDA.
Using two pins of CAD0 and CAD1, lower 2-bit of slave address can be specified.
Completion of sensor signal measurement is posted to the external CPU via INT pin.
The low-voltage specification can be supported by applying 1.85V to the VID pin.
Generates a timing signal required for internal operation based on the OSC generated
clock.
Nonvolatile memory.
Stores initial adjustment values of each sensor at the time of shipment from AKM.
The I²C bus interface is supported.
Accessible through the two pins of SCL and SDA.
Do not write to the EEPROM in ordinary use.
MS0561-E-01 <Preliminary>
-6-
2007/01