AKM AK8973 3-axis electronic compass Datasheet

ASAHI KASEI
[AK8973]
=Preliminary=
AK8973
3-axis Electronic Compass
1. Features
3-axis electronic compass IC
Optimal built-in electronic compass for mobile phones and handy terminals
High sensitivity Hall sensors are integrated.
Functions
•
Built-in 8-bit ADC
•
Built-in amplifier for sensor signal amplification
•
Built-in 8-bit DAC for sensor signal offset compensation
•
Built-in EEPROM for storing individual adjustment values
•
Built-in temperature sensor
•
8-bit digital output
•
Serial interface: I2C bus interface (supporting the low-voltage specification)
•
Automatic power-down function
•
Interrupt function for measurement data ready
•
Built-in master clock oscillator
Operating temperatures:
-30°C to +85°C
Operating supply voltage: +2.5V to +3.6V
Low current consumption/measurement time:
•
Power-down:
0.2μA typ.
•
Magnetic sensor driving:
6.8mA/12.6ms
Package: 16-pin QFN package:
MS0561-E-01 <Preliminary>
4.0mm×4.0mm×0.7mm
-1-
2007/01
ASAHI KASEI
[AK8973]
2. Overview
AK8973 is a geomagnetism detection type electronic compass IC.
The small package of AK8973 integrates magnetic sensors for detecting geomagnetism in the X-axis, Y-axis,
and Z-axis, and arithmetic circuit for processing the signal from each sensor. AK8973 outputs four data in total
as 8-bit digital values respectively: 3-axis magnetic sensor measured values and temperature sensor read value.
By processing the magnetic sensor measured values with an external CPU, azimuth data can be obtained.
By using AK8973 integrated into the system, a navigation system is achieved with reduced space in portable
equipment such as PDA or mobile phone incorporating the GPS function.
Specifically, AK8973 has the following features:
(1) Due to the built-in 8-bit ADC and serial interface, geomagnetism of the X-axis, Y-axis, and Z-axis can be
detected as digital data.
(2) The serial interface corresponds to the I2C bus.
(3) A dedicated power supply is used for the serial interface, so the low-voltage specification can also be
supported by applying 1.85V.
(4) Due to the built-in DAC for compensating the offset magnetic field, the position restraint with parts
which generate the offset magnetic field such as speakers is reduced, and the degree of freedom about
layout is expanded. Note 1)
(5) An EEPROM for storing the individual adjustment values of sensor sensitivity is built-in. The
adjustment values are stored in factory at the time of shipment from AKM.
(6) The built-in temperature sensor as an accessory generates the 8-bit digital A/D-converted value.
The temperature information is not used for azimuth calculation.
(7) The major circuit blocks of AK8973 are activated by the measurement request command from the
controller, and transit to the power-down mode automatically at the end of measurement. That
characteristic realizes the low power consumption required for mobile phones.
(8) The interrupt function for posting the completion of sensor signal measurement to the external CPU is
built-in.
(9) The master clock oscillator is built-in. It is unnecessary to supply the clock from the outside.
Note 1) For AK8973, the offset magnetic field compensation range is approximately ±2.0mT (typical
geomagnetism range is approximately 0.05mT). Depending on usage or required accuracy, use with
the full-range is available. However, for the azimuth measurement by the mobile phones, it is
important to regard the following in the design phase: the magnetic field intensity of offset magnetic
field source (e.g. magnet of speaker) is not fully controlled, and the temperature characteristic
dispersion is noted. With AK8973, it is recommended that the design be performed with the parts
layout where the offset magnetic field of each measurement axis is ±0.8mT or less.
MS0561-E-01 <Preliminary>
-2-
2007/01
ASAHI KASEI
[AK8973]
3. Table of Contents
1.
2.
3.
4.
Features ....................................................................................................................................1
Overview ...................................................................................................................................2
Table of Contents ......................................................................................................................3
Circuit Configuration ..................................................................................................................5
4.1. Block Diagram....................................................................................................................5
4.2. Block Function....................................................................................................................6
4.3. Pin Function .......................................................................................................................7
5. Overall Characteristics ..............................................................................................................8
5.1. Absolute Maximum Ratings................................................................................................8
5.2. Recommended Operating Conditions ................................................................................8
5.3. Electrical Characteristics ....................................................................................................8
5.3.1. DC Characteristics ......................................................................................................8
5.3.2. EEPROM Characteristics............................................................................................9
5.3.3. Analog Circuit Characteristics .....................................................................................9
5.4. Detailed Timing...................................................................................................................9
5.4.1. Various Timing.............................................................................................................9
5.4.2. I2C Bus Interface .......................................................................................................10
6. Functional Explanation ............................................................................................................ 11
6.1. Operation Modes.............................................................................................................. 11
6.2. Description of Each Operation Mode................................................................................12
6.2.1. Power-down Mode ....................................................................................................12
6.2.2. Sensor Measurement Mode ......................................................................................12
6.2.3. EEPROM Mode.........................................................................................................13
6.3. Interrupt Function based on INT Pin.................................................................................13
7. Serial Interface ........................................................................................................................14
7.1. Data Transfer....................................................................................................................14
7.1.1. Change of Data .........................................................................................................14
7.1.2. Start/Stop Condition ..................................................................................................14
7.1.3. Acknowledge.............................................................................................................15
7.1.4. Slave Address ...........................................................................................................15
7.2. WRITE Instruction ............................................................................................................16
7.3. READ Instruction..............................................................................................................17
7.3.1. Current Address READ .............................................................................................17
7.3.2. Random READ..........................................................................................................17
8. Registers .................................................................................................................................18
8.1. Description of Registers ...................................................................................................18
8.2. Register Map....................................................................................................................19
8.3. Detailed Description of Registers .....................................................................................20
8.3.1. ST: Status Register....................................................................................................20
8.3.2. TMPS: Temperature Sensor Data Register ...............................................................20
8.3.3. H1X, H1Y, H1Z: Sensor Data Register......................................................................21
8.3.4. MS1: Mode Setting Register 1 ..................................................................................21
8.3.5. HXDA, HYDA, HZDA: Magnetic Sensor DAC Setting Register.................................22
8.3.6. HXGA, HYGA, HZGA: Magnetic Sensor Gain Setting Register ................................23
9. EEPROM.................................................................................................................................24
9.1. Outline of the Function .....................................................................................................24
9.2. Operation Description.......................................................................................................25
9.2.1. READ Instruction.......................................................................................................25
9.2.1.1.
Current Address READ ......................................................................................25
9.2.1.2.
Random READ ..................................................................................................25
9.2.2. WRITE Instruction .....................................................................................................26
9.2.2.1.
Byte-Write ..........................................................................................................26
9.3. Memory Map ....................................................................................................................27
10. Example of Recommended External Connection ....................................................................28
11. Package ..................................................................................................................................29
11.1. Marking ............................................................................................................................29
11.2. Pin Assignment ................................................................................................................29
MS0561-E-01 <Preliminary>
-3-
2007/01
ASAHI KASEI
[AK8973]
11.3. Outline Dimensions ..........................................................................................................30
11.4. Recommended Foot Print Pattern ....................................................................................30
12. Relationship between the Magnetic Field and Output Code....................................................31
MS0561-E-01 <Preliminary>
-4-
2007/01
ASAHI KASEI
[AK8973]
4. Circuit Configuration
4.1.
Block Diagram
HE-X
Chopper
SW
Integrator
Pre-AMP
ADC
S&H
MUX
HE-Y
HE-Z
DAC
SCL
T-sensor
SDA
HE-Drive
Interface
Logic
&Register
OSC
CAD1
CAD0
RSTN
INT
Timing
Logic
Voltage
Reference
TST1
MS0561-E-01 <Preliminary>
TST2
-5-
TST3
EEPROM
VSS
VID
VDD
2007/01
ASAHI KASEI
4.2.
[AK8973]
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
ASAHI KASEI
4.3.
[AK8973]
Pin Function
Power
supply
system
VID
VID
No.
Pin name
I/O
1
2
3
CAD0
CAD1
VID
I
I
-
4
SDA
I/O
VID
CMOS
5
SCL
I
VID
CMOS
6
TST1
I/O
-
Analog
7
INT
O
VID
CMOS
8
RSTN
I
VID
CMOS
9
NC1
-
-
-
10
11
TST2
TST3
I/O
I/O
-
Analog
Analog
12
13
14
NC2
NC3
NC4
-
-
-
15
16
VDD
VSS
-
MS0561-E-01 <Preliminary>
Type
Function
CMOS
CMOS
POWER
Slave address 0 input pin
Slave address 1 input pin
Digital interface positive power supply pin.
This pin is a positive power supply pin for the digital
interface block. By connecting this pin to a 1.85V power
supply, the low-voltage specification digital interface can be
connected.
Control data input/output pin
Input: Schmidt trigger, Output: Open drain
Control data clock input pin
Input: Schmidt trigger
Test pin
In usual use, eliminate unnecessary wiring, separate this pin
from other test pins, and keep this pin electrically
nonconnected.
Interrupt signal output pin
This pin is used to post the measurement completion to the
external CPU. Refer to 6.3.
Reset pin
This pin resets all the register values when "L" is applied.
After turning the power on, be sure to apply "L".
Nonconnected pin
In usual use, eliminate unnecessary wiring, separate this pin
from other test pins, and keep this pin electrically
nonconnected.
Test pin
In usual use, eliminate unnecessary wiring, separate this pin
from other test pins, and keep this pin electrically
nonconnected.
Nonconnected pin
In usual use, eliminate unnecessary wiring, separate this pin
from other test pins, and keep this pin electrically
nonconnected.
Power supply pin
Ground pin
POWER
POWER
-7-
2007/01
ASAHI KASEI
[AK8973]
5. Overall Characteristics
5.1.
Absolute Maximum Ratings
VSS=0V
Parameter
Symbol
Min.
Max.
Unit
V+
-0.3
+6.5
Power supply voltage
V
(VDD, VID)
VIN
-0.3
(V+)+0.3
Input voltage
V
IIN
Input current
mA
±10
TST
-40
+85
Storage temperature
°C
Note
If the device is used in conditions exceeding these values, the device may be destroyed. Normal operations
and EEPROM data are not guaranteed in such exceeding conditions.
5.2.
Recommended Operating Conditions
VSS=0V
Parameter
Remark
Symbol
Min.
Typ.
Ta
-30
Operating
temperature
VDD
2.5
3.0
Power supply VDD pin voltage
VID
pin
voltage
VID
1.70
1.85
voltage
Note
When turning on/off the power, turn on/off VDD and VID at the same time. .
5.3.
Max.
+85
Unit
°C
3.6
VDD
V
V
Electrical Characteristics
The following conditions apply unless otherwise noted:
VDD=2.5V to 3.6V, VID=1.7V to VDD, Temperature range=-30°C to 85°C
5.3.1. DC Characteristics
Parameter
High level input voltage 1
Symbol
VIH1
Low level input voltage 1
VIL1
High level input voltage 2
Low level input voltage 2
VIH2
VIL2
IIN
Input current (Note 1)
Hysteresis input voltage
(Note 2)
VHS
High level output voltage 1
Low level output voltage 1
Low level output voltage 2
VOH1
VOL1
VOL2
(Note 3)(Note 4)
Current consumption
IDD1
Pin
SCL
SDA
CAD0
CAD1
RSTN
SCL
SDA
CAD0
CAD1
RSTN
SCL
SDA
INT
SDA
Condition
Min.
70%VID
Typ.
Max.
Unit
V
30%VID
V
20%VID
+10
V
V
μA
0.2
0.4
0.4
20%VID
5
V
V
V
V
V
V
μA
80%VID
Vin=VSS or VID
VID≥2V
VID<2V
IOH=-200µA (Note 5)
IOL=+200µA (Note 5)
IOL=3mA VID≥2V
IOL=3mA VID<2V
In power-down mode
-10
5%VID
10%VID
90%VID
IDD2
When magnetic
sensor is driven
6.8
10.2
mA
IDD3
Average when reading
with 100ms
0.8
1.2
mA
(Note 1) Maximum input pin capacitance: 10pF (reference value for design)
(Note 2) Applied to the SCL pin and SDA pin (Schmitt trigger input) (reference value for design)
(Note 3) Maximum load capacitance: 400pF (capacitive load of each bus line applied to the I2C bus interface)
(Note 4) Output is open-drain output. Connect a pull-up resistor externally.
(Note 5) Load capacitance: 20pF
MS0561-E-01 <Preliminary>
-8-
2007/01
ASAHI KASEI
[AK8973]
5.3.2. EEPROM Characteristics
Parameter
EEPROM erase/write cycles
EEPROM data retention
* For write operation, VDD of 2.9V or more is required.
Min.
1000
10 (85°C)
Max.
Unit
Cycles
Years
5.3.3. Analog Circuit Characteristics
Parameter
Symbol
Condition
Min.
Typ.
Max.
Unit
TRS
100
ns
From
rising
edge
of
power
RSTN rise timing
source (VDD, VID) until RSTN
rising edge
TSM
Sum of Ttm+Thm
10.0
12.6
15.1
ms
Time for measurement
(Refer to 6.2.2)
ASR
8
bit
ADC resolution
DRS
8
bit
DAC resolution
DAC step width
DST
VDD=3.0V
124
156
187
μV
LSB
DAC accuracy
DAQ
VDD=3.0V
±1/8
Pre-AMP gain setting range
VDD=3.0V
Lower limit
HASL
Gain setting register: 0H
26.3
26.8
27.3
dB
Upper limit
HASH Gain setting register: FH
32.3
32.8
33.3
dB
(Note 6)
AGS
0.25
0.4
0.55
dB
Pre-AMP gain step width
TOP
-30
85
Temperature
sensor
°C
measurement range
TOC
71H
78H
7FH
code
VDD=3.0V, Tc=35°C
Temperature sensor output
code
TSE
VDD=3.0V(Note 7)
-1.4
-1.6
-1.8
LSB/°C
Temperature
sensor
sensitivity
BSE
420
600
780
LSB
VDD=2.5V Tc=25°C
Magnetic sensor sensitivity
B=
300mT,
Differential
signal
±
(Note 8)
HXGA=HYGA=07H、
HZGA=0AH
(Note 6) Gain setting register of each axis of magnetic sensor. HXGA, HYGA, HZGA.(Refer to 8.3.6.)
(Note 7) Reference value for design
(Note 8) Set the data of EHXGA, EHYGA, EHZGA into HXGA, HYGA, HZGA respectively. The adjustment value
of the pre-AMP gain that becomes 1uT/1LSB is written in low 4bit of EHXGA, EHYGA, and EHZGA.
Higher 4bit of HXGA, HYGA, and HZGA is disregarded even if written. Please copy 8bit data read from
EHXGA, EHYGA, and EHZGA to HXGA, HYGA, and HZGA as it is.
5.4.
Detailed Timing
5.4.1. Various Timing
Parameter
Wait time before mode setting
RSTN Pulse Width
EEPROM access mode turn on
time
EEPROM programming time
MS0561-E-01 <Preliminary>
Symbol
Twat
Trnw
Condition
Min.
100
100
Typ.
300
Twr
10
-9-
Max.
Unit
μs
ns
μs
ms
2007/01
ASAHI KASEI
[AK8973]
5.4.2. I2C Bus Interface
(1) Standard mode at 1.7V≤VID≤VDD
Symbol
Parameter
fSCL
SCL clock frequency
tHIGH
SCL clock "High" time
tLOW
SCL clock "Low" time
tR
SDA and SCL rise time
tF
SDA and SCL fall time
tHD:STA
Start Condition hold time
tSU:STA
Start Condition setup time
tHD:DAT
SDA hold time (vs. SCL falling edge)
tSU:DAT
SDA setup time (vs. SCL rising edge)
tSU:STO
Stop Condition setup time
tBUF
Bus free time
Min.
Typ.
Max.
100
Unit
kHz
μs
μs
μs
μs
μs
μs
μs
ns
μs
μs
4.0
4.7
1.0
0.3
4.0
4.7
0
250
4.0
4.7
(2) Fast mode at 1.7V≤VID≤VDD
Symbol
Parameter
fSCL
SCL clock frequency
tHIGH
SCL clock "High" time
tLOW
SCL clock "Low" time
tR
SDA and SCL rise time
tF
SDA and SCL fall time
tHD:STA
Start Condition hold time
tSU:STA
Start Condition setup time
tHD:DAT
SDA hold time (vs. SCL falling edge)
tSU:DAT
SDA setup time (vs. SCL rising edge)
tSU:STO
Stop Condition setup time
tBUF
Bus free time
tSP
Noise suppression pulse width
Min.
Typ.
Max.
400
Unit
kHz
μs
μs
μs
μs
μs
μs
μs
ns
μs
μs
ns
0.6
1.3
0.3
0.3
0.6
0.6
0
100
0.6
1.3
50
[I2C bus interface timing]
1/fSCL
VIH1
SCL
VIL1
VIH1
SDA
VIL1
tLOW
tBUF
tR
tHIGH
tF
tSP
VIH1
SCL
VIL1
tHD:STA
Stop
tHD:DAT
tSU:DAT
tSU:STA
tSU:STO
Start
Stop
Start
MS0561-E-01 <Preliminary>
- 10 -
2007/01
ASAHI KASEI
[AK8973]
6. Functional Explanation
6.1.
Operation Modes
AK8973 has following three operation modes:
(1) Power-down mode
(2) Sensor measurement mode
(3) EEPROM access mode
By setting MS1 register MODE[1:0] bits, the operation set for each mode is started.
A transition from one mode to another is shown below.
1) Power input VDD
2) Resetting with RSTN pin
MODE[1:0]=00
(1) Power-down
mode
Set measurement
condition.
(2) Sensor measurement mode
MODE[1:0]=11
(normal operation)
On measurement
completion, transitons to
the power-down mode
automatically.
MODE[1:0]=10
(3) EEPROM access mode
MODE[1:0]=11
After turning on the power, perform a reset operation by applying "L" to RSTN pin. Then AK8973 is set to
power-down mode.
A transition to mode (2) or (3) can be made only from power-down mode. A transition to a mode (2) or (3)
must be made through the power-down mode. To make the mode transition, write the setting data into the
MODE[1:0] shown in the transition diagram. After power-down mode is set, at least 100μs(Twat) is needed
before setting another mode.
Be sure to write a measurement condition for sensor measurement mode during the power-down mode.
Write-only registers MS1 and read-only registers can be accessed in any of the modes above.
MS0561-E-01 <Preliminary>
- 11 -
2007/01
ASAHI KASEI
6.2.
[AK8973]
Description of Each Operation Mode
6.2.1. Power-down Mode
Power to all internal circuits is turned off.
During power-down mode, measurement conditions for sensor measurement mode can be set by setting
adequate values to the registers.
The measurement conditions set in the registers are reset only by applying "L" signal to RSTN pin, and not by
a mode transition.
6.2.2. Sensor Measurement Mode
Measurement is made with the sequence below. When the measurement is completed, it transits to
power-down mode automatically.
<Timing Chart>
Measurement timing
Ttm
T
Thm
Power-down mode
I/F-logic
Ttm
H
Write sensor measurement mode
T
Thm
H
Power-down mode
Power-down mode
Write sensor measurement mode
INT bit
INT bit
Measured data read
Measured data read
Be sure to read measured data before starting the next measurement.
Ttm: Temperature sensor measurement period, Thm: Magnetic sensor measurement period
TSM: Ttm+Thm=12.56ms typ.
<Detailed Description>
When sensor measurement mode (MODE[1:0]="00") is set to register at power-down mode, AK8973 starts
measurement operation. First, temperature sensor and 3-axis magnetic sensor are measured in sequence,
automatically. Then, the measured data are stored in the following registers. Finally, AK8973 automatically
transits to power-down mode.
Temperature sensor output result
Register
TMPS[7:0]
Magnetic sensor output result
Register
H1X[7:0], H1Y[7:0], H1Z[7:0]
When AK8973 returns to power-down mode, INT pin is driven to "H" to notify the external CPU that the
measurements have been finished. INT bit is placed in the same state.
When sensor output results are read, INT pin is driven to "L". For the fall timing of INT pin, refer to "6.3.
Interrupt Function based on INT Pin". On the falling edge of INT pin, INT bit also returns to "0".
When the external CPU confirmed that INT pin is driven to "H" or INT bit is set to "1", it should recognize that
the sensor measurements are completed, and then read the mentioned 4-byte data of sensor output results.
<Note>
To execute the sensor measurement mode, INT pin must be "L" or INT bit must be "0". Before executing this
pattern, check that INT pin is "L" or INT bit is "0", or drive INT pin to "L" by performing data register read
operation as dummy. An attempt to set the sensor measurement mode when the INT pin is high is ignored.
Also when the transition of power-down mode is set to the sensor measurement mode or EEPROM access
mode, the contents of magnetic sensor output results of H1X[7:0], H1Y[7:0], and H1Z[7:0] are reset.
MS0561-E-01 <Preliminary>
- 12 -
2007/01
ASAHI KASEI
[AK8973]
6.2.3. EEPROM Mode
This mode is used to access the EEPROM.
In ordinary use, read operation is needed, but write operation must not be performed.
To the EEPROM, the correction values of sensors are written before shipment from AKM. If these correction
values are lost, AK8973 cannot perform operations and measurements normally.
For details, refer to "9. EEPROM".
6.3.
Interrupt Function based on INT Pin
AK8973 has an interrupt function for notifying the external CPU of completion of sensor signal measurement
by transition of INT pin from "L" to "H".
INT pin returns to "L" when any of the registers storing temperature or magnetic sensor output result is read.
On the falling edge of INT pin, INT bit also returns to "0".
In case of current address read, whether any of the registers mentioned above is read is checked. If any of them
is read, INT pin returns to "L" at the timing shown below.
S
T
A
R
T
SDA
S
S
T
O
P
R/W="1"
Slave
Address
Data(n)
A
C
K
Data(n+1)
A
C
K
Data(n+x)
Data(n+2)
A
C
K
A
C
K
A
C
K
P
A
C
K
INT
In case of random read, if the specified address is any of the registers mentioned above, INT pin returns to "L"
at the timing shown below.
S
T
A
R
T
SDA
S
S
T
A
R
T
R/W="0"
Slave
Address
Register
Address(n)
A
C
K
S
A
C
K
S
T
O
P
R/W="1"
Data(n)
Slave
Address
A
C
K
Data(n+x)
Data(n+1)
A
C
K
A
C
K
A
C
K
P
A
C
K
INT
MS0561-E-01 <Preliminary>
- 13 -
2007/01
ASAHI KASEI
[AK8973]
7. Serial Interface
The I2C bus interface of AK8973 supports the standard mode (100kHz max.) and the Fast mode (400kHz
max.).
Both modes can be operable in 1.7V≤VID≤VDD.
7.1.
Data Transfer
To access the AK8973 on the bus, generate a start condition first.
Next, transmit a one-byte slave address including a device address. At this time, AK8973 compares the slave
address with its own address. If these addresses match, AK8973 generates an acknowledgement, and then
executes READ or WRITE instruction. At the end of instruction execution, generate a stop condition.
7.1.1. Change of Data
A change of data on the SDA line must be made during "Low" period of the clock on the SCL line. When the
clock signal on the SCL line is "High", the state of the SDA line must be stable. (Data on the SDA line can be
changed only when the clock signal on the SCL line is "Low".)
During the SCL line is "High", the state of data on the SDA line is changed only when a start condition or a
stop condition is generated.
SCL
SDA
DATA LINE
STABLE :
DATA VALID
CHANGE
OF DATA
ALLOWED
Fig. 01 Data Change
7.1.2. Start/Stop Condition
If the SDA line is driven to "Low" from "High" when the SCL line is "High", a start condition is generated.
Any instruction starts with a start condition.
If the SDA line is driven to "High" from "Low" when the SCL line is "High", a stop condition is generated.
Any instruction stops with a stop condition.
SCL
SDA
START CONDITION
STOP CONDITION
Fig. 02 START and STOP conditions
MS0561-E-01 <Preliminary>
- 14 -
2007/01
ASAHI KASEI
[AK8973]
7.1.3. Acknowledge
The IC that is transmitting data releases the SDA line (in the "High" state) after sending 1-byte data.
The IC that receives the data drives the SDA line to "Low" on the next clock pulse. This operation is referred to
acknowledge. With this operation, whether data has been transferred successfully can be checked.
AK8973 generates an acknowledge after reception of a start condition and slave address.
When a WRITE instruction is executed, AK8973 generates an acknowledge after every byte is received.
When a READ instruction is executed, AK8973 generates an acknowledge then transfers the data stored at the
specified address. Next, AK8973 releases the SDA line then monitors the SDA line. If a master IC generates
an acknowledge instead of a stop condition, AK8973 transmits the 8bit data stored at the next address. If no
acknowledge is generated, AK8973 stops data transmission.
Clock pulse
for acknowledge
SCL FROM
MASTER
1
8
9
DATA
OUTPUT BY
TRANSMITTER
not acknowledge
DATA
OUTPUT BY
RECEIVER
START
CONDITION
acknowledge
Fig. 03 Generation of Acknowledge
7.1.4. Slave Address
The first byte including a slave address is transmitted after a start condition, and an IC to be accessed is
selected from the ICs on the bus according to the slave address.
A slave address of AK8973 consists of 7 bits. The most significant 5 bits are fixed to "00111". The next 2 bits
are address bits used to select an IC to be accessed, and are set by the CAD1-0 pins.
When a slave address is transferred, the IC whose device address matches the transferred slave address
generates an acknowledge then executes an instruction. The 8th bit (least significant bit) of the first byte is a
R/W bit.
When the R/W bit is set to "1", READ instruction is executed. When the R/W bit is set to "0", WRITE
instruction is executed.
MSB
0
LSB
0
1
1
1
CAD1
CAD0
R/W
Fig. 04 Slave Address
MS0561-E-01 <Preliminary>
- 15 -
2007/01
ASAHI KASEI
7.2.
[AK8973]
WRITE Instruction
When the R/W bit is set to "0", AK8973 performs write operation.
In write operation, AK8973 generates an acknowledge after receiving a start condition and the first byte (slave
address) then receives the second byte. The second byte is used to specify the address of an internal control
register and is based on the MSB-first configuration.
MSB
A7
LSB
A6
A5
A4
A3
A2
A1
A0
Fig. 05 Register Address
After receiving the second byte (register address), AK8973 generates an acknowledge then receives the third
byte.
The third byte and after represent control data. Control data consists of 8 bits and is based on the MSB-first
configuration. AK8973 generates an acknowledge after every byte is received. Data transfer always stops with
a stop condition generated by the master.
MSB
D7
LSB
D6
D5
D4
D3
D2
D1
D0
Fig. 06 Control Data
AK8973 can write multiple bytes of data at a time.
After reception of the third byte (control data), AK8973 generates an acknowledge then receives the next data.
If additional data is received instead of a stop condition after receiving one byte of data, the address counter
inside the LSI chip is automatically incremented and the data is written at the next address.
If the writing of data starts at address "E0H", the write address changes from "E0H, E1H through E5H, E6H".
When "E6H" is exceeded, the internal address counter rolls over, and the following data is written in
sequentially starting at address "E0H" again.
S
T
A
R
T
SDA
S
S
T
O
P
R/W="0"
Slave
Address
Data(n)
Register
Address(n)
A
C
K
A
C
K
Data(n+x)
Data(n+1)
A
C
K
A
C
K
A
C
K
P
A
C
K
Fig. 07 WRITE Operation
MS0561-E-01 <Preliminary>
- 16 -
2007/01
ASAHI KASEI
7.3.
[AK8973]
READ Instruction
When the R/W bit is set to "1", AK8973 performs read operation.
If a master IC generates an acknowledge instead of a stop condition after AK8973 transfers the data at a
specified address, the data at the next address can be read.
If the reading of data starts from "C0H, C1H through C3H, C4H" or "E0H, E1H through E5H, E6H", and
additional data is read after reading, the internal address counter rolls over and the data at "C0H" or "E0H" is
read again.
AK8973 supports current address read and random read.
7.3.1. Current Address READ
AK8973 has an address counter inside the LSI chip. In current address read operation, the data at an address
specified by this counter is read.
The internal address counter holds the next address of the most recently accessed address.
For example, if the address most recently accessed (for READ instruction) is address "n", and a current address
read operation is attempted, the data at address "n+1" is read.
In current address read operation, AK8973 generates an acknowledge after receiving a slave address for the
READ instruction (R/W bit="1"). Next, AK8973 transfers the data specified by the internal address counter
starting with the next clock pulse, then increments the internal counter by one. If the master IC generates a stop
condition instead of an acknowledge after AK8973 transmits one byte of data, the read operation stops.
S
T
A
R
T
SDA
S
S
T
O
P
R/W="1"
Slave
Address
Data(n)
A
C
K
Data(n+1)
A
C
K
Data(n+2)
A
C
K
Data(n+x)
A
C
K
A
C
K
P
A
C
K
Fig. 08 CURRENT ADDRESS READ
7.3.2. Random READ
By random read operation, data at an arbitrary address can be read.
Random read operation requires to execute WRITE instruction as dummy before a slave address for the READ
instruction (R/W bit="1") is transmitted. In random read operation, a start condition is first generated then a
slave address for the WRITE instruction (R/W bit="0") and a read address are transmitted sequentially.
After AK8973 generates an acknowledge in response to this address transmission, a start condition and a slave
address for the READ instruction (R/W bit="1") are generated again. AK8973 generates an acknowledge in
response to this slave address transmission. Next, AK8973 transfers the data at the specified address then
increments the internal address counter by one. If the master IC generates a stop condition instead of an
acknowledge after data is transferred, the read operation stops.
S
T
A
R
T
SDA
S
S
T
A
R
T
R/W="0"
Register
Address(n)
Slave
Address
A
C
K
S
A
C
K
S
T
O
P
R/W="1"
Data(n)
Slave
Address
A
C
K
Data(n+1)
A
C
K
Data(n+x)
A
C
K
A
C
K
P
A
C
K
Fig. 09 RANDOM READ
MS0561-E-01 <Preliminary>
- 17 -
2007/01
ASAHI KASEI
[AK8973]
8. Registers
8.1.
Description of Registers
AK8973 has registers of 13 addresses as indicated in Table 1. Every address consists of 8 bits data. Data is
transferred to or received from the external CPU via the serial interface described previously.
ST
C0H
READ/
WRITE
READ
TMPS
C1H
READ
H1X
H1Y
H1Z
MS1
C2H
C3H
C4H
E0H
READ
HXDA
E1H
HYDA
E2H
HZDA
E3H
HXGA
E4H
HYGA
E5H
HZGA
E6H
READ/
WRITE
TS1
5DH
READ/
WRITE
Name
Address
Description
Status register
Temperature sensor data
register
Magnetic sensor data register
READ/
WRITE
Mode setting register
READ/
WRITE
READ/
WRITE
Magnetic sensor X-axis DAC
setting register
Magnetic sensor Y-axis DAC
setting register
Magnetic sensor Z-axis DAC
setting register
Magnetic sensor X-axis gain
setting register
Magnetic sensor Y-axis gain
setting register
Magnetic sensor Z-axis gain
setting register
Test mode setting register
READ/
WRITE
READ/
WRITE
READ/
WRITE
Explanation
Interrupt
EEPROM write enabled/disabled
Temperature sensor data read
X-axis data read
Y-axis data read
Z-axis data read
Operation mode setting
EEPROM write enable/disable
setting
X-axis offset DAC setting value
Y-axis offset DAC setting value
Z-axis offset DAC setting value
X-axis AMP gain setting value
Y-axis AMP gain setting value
Z-axis AMP gain setting value
Not to be used by the user.
Used for testing before shipment
Table 1
MS0561-E-01 <Preliminary>
- 18 -
2007/01
ASAHI KASEI
8.2.
[AK8973]
Register Map
Register Name
Addr
Read-only Register
C0H
ST
C1H
TMPS
C2H
H1X
C3H
H1Y
C4H
H1Z
Write/read register
E0H
MS1
E1H
HXDA
E2H
HYDA
E3H
HZDA
E4H
HXGA
E5H
HYGA
E6H
HZGA
5DH
TS1
D7
D6
D5
D4
D3
D2
D1
D0
0
TMPS7
H1X7
H1Y7
H1Z7
0
TMPS6
H1X6
H1Y6
H1Z6
0
TMPS5
H1X5
H1Y5
H1Z5
0
TMPS4
H1X4
H1Y4
H1Z4
0
TMPS3
H1X3
H1Y3
H1Z3
0
TMPS2
H1X2
H1Y2
H1Z2
WEN
TMPS1
H1X1
H1Y1
H1Z1
INT
TMPS0
H1X0
H1Y0
H1Z0
WEN4 WEN3 WEN2 WEN1 WEN0
0
MODE1
HXDA7 HXDA6 HXDA5 HXDA4 HXDA3 HXDA2 HXDA1
HYDA7 HYDA6 HYDA5 HYDA4 HYDA3 HYDA2 HYDA1
HZDA7 HZDA6 HZDA5 HZDA4 HZDA3 HZDA2 HZDA1
0
0
0
0
HXGA3 HXGA2 HXGA1
0
0
0
0
HYGA3 HYGA2 HYGA1
0
0
0
0
HZGA3 HZGA2 HZGA1
-
MODE0
HXDA0
HYDA0
HZDA0
HXGA0
HYGA0
HZGA0
-
When the RSTN pin is driven to "L", all registers of AK8973 are initialized, resulting in power-down mode.
During sensor measurement mode, only MS1 register can be written in. Do not write in the registers other
than MS1.
TS1 is test mode setting addresses for testing before shipment. Do not use TS1. Otherwise, the operation
error may result.
MS0561-E-01 <Preliminary>
- 19 -
2007/01
ASAHI KASEI
8.3.
[AK8973]
Detailed Description of Registers
8.3.1. ST: Status Register
Register
Addr
D7
name
Read-only register
C0H
ST
0
Reset
0
D6
D5
D4
D3
D2
D1
D0
0
0
0
0
0
0
0
0
0
0
WEN
0
INT
0
D3
D2
D1
D0
TMPS3
0
TMPS2
0
TMPS1
0
TMPS0
0
INT: Interrupt flag bit
"0":
Interrupt reset state
"1":
Interrupt state
(This bit is valid only in sensor measurement mode (not valid in other modes).)
WEN: EEPROM write enabled/disabled state check bit
"0":
Read mode
"1":
Write mode
8.3.2. TMPS: Temperature Sensor Data Register
Register
Addr
D7
D6
D5
D4
name
Read-only register
C1H
TMPS
TMPS7 TMPS6 TMPS5 TMPS4
Reset
0
0
0
0
TMPS[7:0]: Temperature sensor output data
Temperature sensor (T-Sensor) converted data 8 bits
TMPS code
E0H
D0H
C0H
B0H
A0H
90H
80H
70H
60H
50H
40H
30H
20H
MS0561-E-01 <Preliminary>
Temperature [°C]
-30
-20
-10
0
10
20
30
40
50
60
70
80
90
Table 2
- 20 -
2007/01
ASAHI KASEI
[AK8973]
8.3.3. H1X, H1Y, H1Z: Sensor Data Register
Addr Register name
D7
D6
D5
Read-only register
C2H
H1X
H1X7
H1X6
H1X5
C3H
H1Y
H1Y7
H1Y6
H1Y5
C4H
H1Z
H1Z7
H1Z6
H1Z5
Reset
0
0
0
D4
D3
D2
D1
D0
H1X4
H1Y4
H1Z4
0
H1X3
H1Y3
H1Z3
0
H1X2
H1Y2
H1Z2
0
H1X1
H1Y1
H1Z1
0
H1X0
H1Y0
H1Z0
0
D1
D0
H1X/H1Y/H1Z: Magnetic sensor X-axis/Y-axis/Z-axis output result
H1X[7:0]: X-axis output result
H1Y[7:0]: Y-axis output result
H1Z[7:0]: Z-axis output result
Minimum value: 00H
Maximum value: FFH
8.3.4. MS1: Mode Setting Register 1
Addr Register name
D7
D6
Write/read register
E0H
MS1
WEN4
WEN3
Reset
0
0
D5
D4
D3
D2
WEN2
0
WEN1
0
WEN0
0
0
0
MODE1 MODE0
1
1
MODE[1:0]: Operation mode setting
"00": Sensor measurement mode
"01": Setting prohibited
"10": EEPROM access mode
"11": Power-down mode
WEN[4:0]: Setting to enable/disable EEPROM data write
"10101":
Write mode (write enabled)
Other than "10101":
Read mode (write disabled)
MS0561-E-01 <Preliminary>
- 21 -
2007/01
ASAHI KASEI
[AK8973]
8.3.5. HXDA, HYDA, HZDA: Magnetic Sensor DAC Setting Register
Register
Addr
D7
D6
D5
D4
D3
D2
D1
D0
name
Write/read register
E1H
HXDA
HXDA7 HXDA6 HXDA5 HXDA4 HXDA3 HXDA2 HXDA1 HXDA0
E2H
HYDA
HYDA7 HYDA6 HYDA5 HYDA4 HYDA3 HYDA2 HYDA1 HYDA0
E3H
HZDA
HZDA7 HZDA6 HZDA5 HZDA4 HZDA3 HZDA2 HZDA1 HZDA0
Reset
0
0
0
0
0
0
0
0
HXDA[7:0]: Magnetic sensor X-axis offset DAC setting
HYDA[7:0]: Magnetic sensor Y-axis offset DAC setting
HZDA[7:0]: Magnetic sensor Z-axis offset DAC setting
Setting
FFH
FEH
:
81H
80H
00H
01H
:
7EH
7FH
Set voltage [μV]
156.25μV/step
+19843.75
+19687.50
:
+156.25
+0
-0
-156.25
:
-19687.50
-19843.75
Table 3
[DAC output]
+
Zero
00H
7FH 80H
FFH
[ DAC code setting (HXDA, HYDA, HZDA)]
MS0561-E-01 <Preliminary>
- 22 -
2007/01
ASAHI KASEI
[AK8973]
8.3.6. HXGA, HYGA, HZGA: Magnetic Sensor Gain Setting Register
Register
Addr
D7
D6
D5
D4
D3
D2
D1
D0
name
Write/read register
E4H
HXGA
0
0
0
0
HXGA3 HXGA2 HXGA1 HXGA0
E5H
HYGA
0
0
0
0
HYGA3 HYGA2 HYGA1 HYGA0
E6H
HZGA
0
0
0
0
HZGA3 HZGA2 HZGA1 HZGA0
Reset
0
0
0
0
0
0
0
0
HXGA[3:0]: Magnetic sensor X-axis gain setting
HYGA[3:0]: Magnetic sensor Y-axis gain setting
HZGA[3:0]: Magnetic sensor Z-axis gain setting
Gain setting=(26.8+0.4×N)dB N=0 to 15
Setting
0H
1H
2H
3H
4H
5H
6H
7H
8H
9H
AH
BH
CH
DH
EH
FH
MS0561-E-01 <Preliminary>
Gain [dB]
26.8
27.2
27.6
28.0
28.4
28.8
29.2
29.6
30.0
30.4
30.8
31.2
31.6
32.0
32.4
32.8
Table 4
- 23 -
2007/01
ASAHI KASEI
[AK8973]
9. EEPROM
9.1.
Outline of the Function
Caution
Never write in EEPROM.
Device-specific adjusted values are stored before shipment in AKM.
Write operation is not needed in user operation. It may loose adjusted values.
If these adjusted values are lost, AK8973 cannot operate normally.
AK8973 includes an EEPROM consisting of 7 words by 8 bits. Each word can be read and written
independently.
Two interfaces, I2C bus standard mode (100kHz max.) and fast mode (400kHz max.), are supported.
Before reading from or writing in the EEPROM, be sure to write "10" into MODE[1:0] bit of register MS1 and
set the operation mode to EEPROM access mode. By this setting, the circuits such as the reference voltage
circuit needed for the EEPROM access mode are started up (start-up wait time: 300μs).
A high voltage required for write operation is generated inside the device.
The EEPROM can be read from or written in depending on the setting of the "EEPROM data write
enable/disable setting" which is written in the WEN[4:0] bit of register MS1.
Operation
Read
Write
WEN[4:0] bit
setting
Other than "10101"
"10101"
Address
section
A7-A0
A7-A0
Data section
Description
ED7-ED0 (out)
ED7-ED0 (in)
EEPROM memory read
EEPROM memory write
Table 5
* WEN bit of ST register can be used to check if the current mode is the read mode or write mode.
When the EEPROM access mode is completed, set the MODE[1:0] to "11" for power-down, and then transit to
another mode.
MS0561-E-01 <Preliminary>
- 24 -
2007/01
ASAHI KASEI
9.2.
[AK8973]
Operation Description
EEPROM read and write operations are controlled by SCL pin, SDA pin, CAD1 pin, CAD0 pin, and
WEN[4:0] bit. The function of "data transfer" is the same as described in 7.1.
9.2.1. READ Instruction
Data can be read from the EEPROM by accessing an EEPROM address in the read mode (write disabled).
AK8973 has two READ instructions of current address read and random read. To terminate READ operation,
set MODE[1:0] of MS1 to "11" to transit to power-down mode.
9.2.1.1. Current Address READ
AK8973 has an address counter inside the LSI chip. In current address read operation, the data at an address
specified by this counter is read.
The internal address counter holds the next address of the most recently accessed address.
If the address most recently accessed (for WRITE or READ instruction) is address "n", and a current address
read operation is attempted, the data at address "n+1" is read.
For example, if read operations are performed in succession, data is read from 62H, 63H through 67H, 68H,
62H, and so on in this order.
In current address read operation, AK8973 generates an acknowledge after receiving a slave address for the
READ instruction (R/W bit="1"). Next, AK8973 transfers the data specified by the internal address counter
starting with the next clock pulse, then increments the internal counter by one. If the master IC generates a stop
condition instead of an acknowledge after AK8973 transmits one byte of data, the read operation stops.
S
T
A
R
T
SDA
S
S
T
O
P
R/W="1"
Slave
Address
Data(n)
A
C
K
Data(n+1)
A
C
K
Data(n+2)
A
C
K
Data(n+x)
A
C
K
A
C
K
P
A
C
K
Fig. 10 CURRENT ADDRESS READ
9.2.1.2. Random READ
By random read operation, data at an arbitrary address can be read.
Random read operation requires to execute WRITE instruction as dummy before a slave address for the READ
instruction (R/W bit="1") is transmitted. In random read operation, a start condition is first generated then a
slave address for the WRITE instruction (R/W bit="0") and a read address are transmitted sequentially.
After AK8973 generates an acknowledge in response to this address transmission, a start condition and a slave
address for the READ instruction (R/W bit="1") are generated again. AK8973 generates an acknowledge in
response to this slave address transmission. Next, AK8973 transfers the data at the specified address then
increments the internal address counter by one. If the master IC generates a stop condition instead of an
acknowledge after data is transferred, the read operation stops.
S
T
A
R
T
SDA
S
S
T
A
R
T
R/W="0"
Slave
Address
Register
Address(n)
A
C
K
S
A
C
K
S
T
O
P
R/W="1"
Data(n)
Slave
Address
A
C
K
Data(n+1)
A
C
K
Data(n+x)
A
C
K
A
C
K
P
A
C
K
Fig. 11 RANDOM READ
MS0561-E-01 <Preliminary>
- 25 -
2007/01
ASAHI KASEI
[AK8973]
9.2.2. WRITE Instruction
9.2.2.1. Byte-Write
Data is written at a specified address. A stop condition is required for every byte of data writing.
Input a start condition, slave address (R/W="0"), address, and data in this order.
AK8973 generates an acknowledge after receiving a slave address, after receiving an address, and after
receiving data.
Upon reception of a stop condition, AK8973 starts an internal programming cycle.
During the internal programming cycle, avoid making accesses to any valid addresses of AK8973 for
operations including read and write operations for registers.
To stop the WRITE instruction, set WEN[4:0] bits of the MS1 register to other than "10101" when the internal
programming time or more has elapsed. If the programming time is insufficient, correct writing of the last data
is not guaranteed.
In case that data is written in successively.
W EN[4:0]
"10101"
S
T
A
R
T
SDA
S
S
T
O
P
R/W ="0"
Slave
Address
Register
Address(n)
A
C
K
Data(n)
A
C
K
Twr: 10ms
S
T
A
R
T
S
P
A
C
K
R/W ="0"
Slave
Address
A
C
K
In case of stopping write operation.
W EN[4:0]
"10101"
S
T
A
R
T
SDA
S
Other than "10101"
S
T
O
P
R/W ="0"
Slave
Address
Register
Address(n)
A
C
K
Data(n)
A
C
K
Twr: 10ms
P
A
C
K
Fig. 12 Byte-write
MS0561-E-01 <Preliminary>
- 26 -
2007/01
ASAHI KASEI
9.3.
[AK8973]
Memory Map
Table 6 indicates the EEPROM memory map. There are eight addresses in total.
Do not rewrite any data written in the EEPROM.
Name
Address
A7 to A0
Data
Description
Number
of bits
8
ETS
62H
Offset adjustment for temperature sensor [5:0]
EVIR
63H
8
EIHE
64H
ETST
65H
VREF (EVIR[7:4]) & IREF (EVIR[3:0])
adjustment value
HE drive power supply correction value [7:4] &
OSC adjustment value [3:0]
For testing
EHXGA
66H
Magnetic sensor X-axis gain adjustment value
8
EHYGA
67H
Magnetic sensor Y-axis gain adjustment value
8
EHZGA
68H
Magnetic sensor Z-axis gain adjustment value
8
WRAL1
60H
Address for batch EEPROM write
Table 6
-
8
8
Factory-set
value
Individual
adjustment value
Individual
adjustment value
Individual
adjustment value
Individual
adjustment value
Individual
adjustment value
Individual
adjustment value
Individual
adjustment value
-
<ETS, EVIR, EIHE>
These data items are internally connected to registers of AK8973 to directly control adjustment values. Data
other than ETS, EVIR, and EIHE is not directly connected to internal registers of AK8973.
<ETST>, <WRAL1>
Addresses for testing. Usually, do not access these addresses.
<EHXGA, EHYGA, EHZGA>
These addresses are used for magnetic sensor adjustment. These data items are read and set to HXGA, HYGA
and HZGA registers respectively to adjust the sensitivity of each axis of the magnetic sensors.
At addresses other than the above addresses, the EEPROM circuit of AK8973 does not operate.
MS0561-E-01 <Preliminary>
- 27 -
2007/01
ASAHI KASEI
[AK8973]
10.
Example of Recommended External Connection
Pull up the bus of SDA pin to VID.
VID
AK8973
SDA
Other LSI on
same I2C bus
VID (1.7V-VDD)
VDD (2.5V - 3.6V)
VDD
VID
0.1μF
0.1μF
SCL
SDA
INT
RSTN
Connect to the external CPU
CAD0
CAD1
Fix to VSS or VID to
assign the slave address
AK8973
VSS
TST1
TST2
TST3
NC1
NC2
NC3
NC4
Open
Open
Open
Open
Open
Open
Open
MS0561-E-01 <Preliminary>
- 28 -
2007/01
ASAHI KASEI
[AK8973]
11.
Package
11.1. Marking
• Company logo: AKM
• Product name: 8973
• Date code:
X1X2X3X4
= Year
X1
X2X3 = Week
= Lot
X4
AKM
8973
XXXX
11.2. Pin Assignment
9
16
NC1
VSS
10
15
TST2
VDD
11
14
TST3
NC4
12
13
NC2
NC3
AK8973
Top View
3
4
CAD1
VID
SDA
CAD0
2
1
MS0561-E-01 <Preliminary>
- 29 -
8
RSTN
7
INT
6
TST1
5
SCL
2007/01
ASAHI KASEI
[AK8973]
11.3. Outline Dimensions
[mm]
11.4. Recommended Foot Print Pattern
[mm]
MS0561-E-01 <Preliminary>
- 30 -
2007/01
ASAHI KASEI
12.
[AK8973]
Relationship between the Magnetic Field and Output Code
The AD converter code increases as the magnetic flux density increases in the arrow directions.
On the Z-axis, the AD converter code increases as the magnetic flux density in the direction from the back of
the package to the front face increases.
Z
Ｘ
Y
AKM
8973
XXXX
Top View
Important Notice
•
•
•
•
•
These products and their specifications are subject to change without notice. Before considering any use or
application, consult the Asahi Kasei Microsystems Co., Ltd. (AKM) sales office or authorized distributor
concerning their current status.
AKM assumes no liability for infringement of any patent, intellectual property, or other right in the
application or use of any information contained herein.
Any export of these products, or devices or systems containing them, may require an export license or other
official approval under the law and regulations of the country of export pertaining to customs and tariffs,
currency exchange, or strategic materials.
AKM products are neither intended nor authorized for use as critical components in any safety, life support,
or other hazard related device or system, and AKM assumes no responsibility relating to any such use,
except with the express written consent of the Representative Director of AKM. As used here:
(a) A hazard related device or system is one designed or intended for life support or maintenance of
safety or for applications in medicine, aerospace, nuclear energy, or other fields, in which its failure
to function or perform may reasonably be expected to result in loss of life or in significant injury or
damage to person or property.
(b) A critical component is one whose failure to function or perform may reasonably be expected to
result, whether directly or indirectly, in the loss of the safety or effectiveness of the device or system
containing it, and which must therefore meet very high standards of performance and reliability.
It is the responsibility of the buyer or distributor of an AKM product who distributes, disposes of, or
otherwise places the product with a third party to notify that party in advance of the above content and
conditions, and the buyer or distributor agrees to assume any and all responsibility and liability for and hold
AKM harmless from any and all claims arising from the use of said product in the absence of such
notification.
MS0561-E-01 <Preliminary>
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2007/01