AK8975 Datasheet, PDF (2/34 Pages) Asahi Kasei Microsystems – 3-axis Electronic Compass

[AK8975/C]


2. Overview
AK8975/C is 3-axis electronic compass IC with high sensitive Hall sensor technology.
Small package of AK8975/C incorporates magnetic sensors for detecting terrestrial magnetism in the X-axis,
Y-axis, and Z-axis, a sensor driving circuit, signal amplifier chain, and an arithmetic circuit for processing the
signal from each sensor. Self test function is also incorporated. From its compact foot print and thin package
feature, it is suitable for map heading up purpose in GPS-equipped cell phone to realize pedestrian navigation
function.
AK8975/C has the following features:
(1) Silicon monolithic Hall-effect magnetic sensor with magnetic concentrator realizes 3-axis magnetometer
on a silicon chip. Analog circuit, digital logic, power block and interface block are also integrated on a
chip.
(2) Wide dynamic measurement range and high resolution with lower current consumption.
Output data resolution:
13 bit (0.3 µT / LSB)
Measurement range:
±1200 µT
Average power consumption at 8Hz repetition rate: 350 µA typ.
(3) Digital serial interface
- I²C bus interface to control AK8975/C functions and to read out the measured data by external CPU. A
dedicated power supply for I²C bus interface can work in low-voltage apply as low as 1.65V.
- 4-wire SPI is also supported. A dedicated power supply for SPI can work in low-voltage apply as low as
1.65V.
(4) DRDY pin and register inform to system that measurement is end and set of data in registers are ready to
be read.
(5) Device is worked by on-chip oscillator so no external clock source is necessary.
(6) Self test function with internal magnetic source to confirm magnetic sensor operation on end products.
MS1187-E-02
-2-
2010/05