AK8963 Datasheet, PDF (4/18 Pages) Asahi Kasei Microsystems – 3-axis Electronic Compass

[AK8963]
4.1. Block Diagram
4. Circuit Configuration
3-axis
Hall
sensor
MUX
Chopper
SW
Pre-
AMP
Integrator & ADC
Magnetic source
HE-Drive
Voltage
Reference
OSC1
Timing
Control
OSC2
POR
Interface,
Logic
& Register
FUSE ROM
RSTN
SCL/SK
SDA/SI
CSB
SO
DRDY
RSV
CAD0
CAD1 _TST1
TRIG
VSS VDD VID
4.2. Block Function
Block
Function
3-axis Hall sensor _{Monolithic Hall elements.}
MUX
Multiplexer for selecting Hall elements.
Chopper SW
Performs chopping.
HE-Drive
Magnetic sensor drive circuit for constant-current driving of sensor
Pre-AMP
Fixed-gain differential amplifier used to amplify the magnetic sensor signal.
Integrator & ADC
Integrates and amplifies pre-AMP output and performs analog-to-digital
conversion.
OSC1
Generates an operating clock for sensor measurement.
12MHz(typ.)
OSC2
Generates an operating clock for sequencer.
128kHz(typ.)
POR
Power On Reset circuit. Generates reset signal on rising edge of VDD.
Interface Logic &
Register
Exchanges data with an external CPU.
DRDY pin indicates sensor measurement end and data is ready to be read.
I²C bus interface using two pins, namely, SCL and SDA. Standard mode and Fast
mode are supported. The low-voltage specification can be supported by applying
1.65V to the VID pin.
4-wire SPI is also supported by SK, SI, SO and CSB pins.
4-wire SPI works in VID pin voltage down to 1.65V, too.
Timing Control
Generates a timing signal required for internal operation from a clock generated
by the OSC1.
Magnetic Source _{Generates magnetic field for self test of magnetic sensor.}
FUSE ROM
Fuse for adjustment
ShortDatasheet-E-01
-4-
2012/02