VTI CMA3000-D01DEMO 3-axis accelerometer Datasheet

Doc.Nr. 8281000.12
Product Family Specification
CMA3000-D0X Series
3-axis accelerometer
CMA3000-D0X Series
TABLE OF CONTENTS
1 General Description ........................................................................................................... 5
1.1
Introduction ................................................................................................................................5
1.2 Functional Description ..............................................................................................................5
1.2.1 Sensing element..................................................................................................................5
1.2.2 Interface IC...........................................................................................................................5
1.2.3 Factory calibration ..............................................................................................................5
1.2.4 Supported features .............................................................................................................6
1.2.5 Operation modes.................................................................................................................6
1.2.5.1
1.2.5.2
1.2.5.3
1.2.5.4
1.2.6
1.2.7
Power Down .................................................................................................................................6
Measurement................................................................................................................................6
Motion Detection..........................................................................................................................6
Free-Fall Detection ......................................................................................................................6
Interrupt................................................................................................................................6
Operational flow chart ........................................................................................................7
2 Reset and power up, Operation Modes, HW functions and Clock ................................. 8
2.1
Reset and power up...................................................................................................................8
2.2
Power Down mode.....................................................................................................................8
2.3 Measurement Mode ...................................................................................................................8
2.3.1 Description...........................................................................................................................8
2.3.2 Usage....................................................................................................................................8
2.4 Motion Detection Mode .............................................................................................................8
2.4.1 Description...........................................................................................................................8
2.4.2 Usage....................................................................................................................................9
2.4.3 Example..............................................................................................................................10
2.5 Free-Fall Detection...................................................................................................................10
2.5.1 Description.........................................................................................................................10
2.5.2 Usage..................................................................................................................................10
2.5.3 Example..............................................................................................................................10
2.6 Interrupt function (INT-pin) .....................................................................................................11
2.6.1 Usage..................................................................................................................................11
2.7
Clock .........................................................................................................................................11
3 Addressing Space ............................................................................................................ 12
3.1
Register Description................................................................................................................12
3.2
Non-volatile memory ...............................................................................................................12
3.3
Registers...................................................................................................................................12
4 Serial Interfaces ............................................................................................................... 17
4.1
SPI Interface .............................................................................................................................17
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4.1.1
4.1.2
SPI frame format................................................................................................................17
Examples of SPI communication.....................................................................................18
4.1.2.1
4.1.3
Example of register read...........................................................................................................18
Multiple slave devices in SPI bus ....................................................................................18
4.2 I2C Interface ..............................................................................................................................19
4.2.1 I2C frame format.................................................................................................................19
4.2.1.1
4.2.1.2
4.2.2
I2C write mode ............................................................................................................................19
I2C read mode.............................................................................................................................19
Examples of I2C communication......................................................................................19
5 Electrical Characteristics ................................................................................................ 20
5.1
Absolute maximum ratings.....................................................................................................20
5.2
Power Supply ...........................................................................................................................20
5.3 Digital I/O Specification...........................................................................................................20
5.3.1 Digital I/O DC characteristics ...........................................................................................20
5.3.2 Digital I/O level shifter.......................................................................................................20
5.3.3 SPI AC characteristics ......................................................................................................21
5.3.4 I2C AC characteristics .......................................................................................................21
6 Package Characteristics.................................................................................................. 22
6.1
Dimensions...............................................................................................................................22
7 Application information ................................................................................................... 23
7.1
Pin Description.........................................................................................................................23
7.2
Recommended circuit diagram ..............................................................................................23
7.3
Recommended PWB layout ....................................................................................................24
7.4
Mounting recommendations...................................................................................................24
7.5
Assembly instructions ............................................................................................................25
7.6
Tape and reel specifications...................................................................................................25
8 Data sheet references ...................................................................................................... 26
8.1 Offset.........................................................................................................................................26
8.1.1 Offset calibration error .....................................................................................................26
8.1.2 Offset temperature error...................................................................................................26
8.2 Sensitivity .................................................................................................................................26
8.2.1 Sensitivity calibration error..............................................................................................27
8.2.2 Sensitivity temperature error ...........................................................................................27
8.3
Linearity ....................................................................................................................................27
8.4
Noise .........................................................................................................................................28
8.5
Bandwidth.................................................................................................................................29
8.6
Cross-axis sensitivity ..............................................................................................................29
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8.7
Turn-on time .............................................................................................................................30
9 Known issues ................................................................................................................... 31
9.1 Acceleration data reading via I2C bus....................................................................................31
9.1.1 Interrupt based acceleration reading ..............................................................................31
9.1.2 Acceleration reading without interrupts .........................................................................32
9.2
Leakage current when VDD - DVIO > 0.3 V ............................................................................32
10 Order Information............................................................................................................. 33
11 Document Change Control.............................................................................................. 34
12 Contact Information ......................................................................................................... 35
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1
General Description
1.1
Introduction
CMA3000-D0X is a three axis accelerometer family targeted for high volume products requiring
small size, low price and low power consumption. It consists of a 3D-MEMS sensing element and a
signal conditioning ASIC in a wafer level package.
Block diagram of CMA3000-D0X is shown in Figure 1 below.
C/V
Analog
calibration
&
ADC
DEMUX
1:3
Low-pass
Filter
Low-pass
Filter
SCK/SCL
SPI
&
I2C
i/f
Reference
NonVolatile
Memory
Motion
detector
Free fall
detector
MOSI/SDA
CSB
Low-pass
Filter
Oscillator
&
clock
MISO
Control
&
INT
INT
Figure 1. CMA3000-D0X block diagram with digital SPI and I2C interface
This document, no. 8281000, describes the product specification (e.g. operation modes, user
accessible registers, electrical properties and application information) for the CMA3000-D0X family.
The specification for an individual sensor is available in the corresponding data sheet.
1.2
1.2.1
Functional Description
Sensing element
The sensing element is manufactured using proprietary bulk 3D-MEMS process, which enables
robust, stable and low noise & power capacitive sensors.
The sensing element consists of three acceleration sensitive masses. Acceleration will cause a
capacitance change that will be then converted into a voltage change in the signal conditioning
ASIC.
1.2.2
Interface IC
CMA3000 includes an internal oscillator, reference and non-volatile memory that enable the
sensor's autonomous operation within a system.
The sensing element is interfaced via a capacitance-to-voltage (CV) converter. Following
calibration in the analog domain, the signal is A/D-converted and then digitally filtered. Sensor
output is user selectable digital SPI or I2C interface.
In measurement mode acceleration data can be read via the serial bus and in power down mode
the device is in-active. Other supported features are motion and free-fall detection. In these modes,
the sensor will generate an interrupt when a pre-defined condition has been met. Measurement
range can be selected by register command.
1.2.3
Factory calibration
Sensors are factory calibrated. Trimmed parameters are gain, offset, internal current reference and
frequency of the internal oscillator. Calibration parameters will be read automatically from the
internal non-volatile memory during sensor startup.
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1.2.4
Supported features
Supported features are listed in Table 1 below.
Table 1. CMA3000-D0X devices’ summary.
1.2.5
1.2.5.1
Features
CMA3000-D01
Supply voltage
I/O voltage
Measuring range (selectable)
Resolution (2g /8g range)
Sensitivity (2g /8g range)
Motion detection
Free fall detection
Interface
Clock
1.7 V – 3.6 V
1.7 V – 3.6 V
±2 g, ±8 g
17 mg / 67 mg
56 counts/g / 14 counts/g
User enabled
User enabled
SPI max 500 kHz, I2C fast mode 400 kHz
Internal
Operation modes
Power Down
In Power Down (PD) mode device's volatile register keep their contents and the current
consumption is minimized. Power down mode is the default mode after start up.
1.2.5.2
Measurement
In Measurement mode (Meas) the sensor offers acceleration information via the digital SPI/I2C
interface. Interrupt can be activated via INT-pin, when each xyz-acceleration sample is ready to be
read.
Measurement range and sample rate are user selectable according to Table 2. Measurement mode
can be activated by detected motion.
1.2.5.3
Motion Detection
Motion Detection (MD) mode is intended to be used to save system level power consumption. In
this mode, CMA3000-D0X activates the interrupt via the INT-pin when motion is detected. Motion
sensitivity level can be configured via the SPI or I2C bus. Moreover, duration of the motion to be
detected can be user defined. Once the interrupt has happened, the detected direction can be read
out from the corresponding status register.
Low sample rate (10 Hz) band-pass filtered acceleration information is available in MD mode. The
device can be configured to switch automatically into the measurement mode with highest
sampling rate after motion detection.
1.2.5.4
Free-Fall Detection
Free-Fall Detection (FFD) is intended to be used to save system resources. This feature activates
the interrupt via the INT-pin when free-fall is detected. Acceleration information is available when
the FFD is enabled.
1.2.6
Interrupt
The CMA3000 has a dedicated output pin (INT) to be used as the interrupt for the master
controller. Interrupt conditions can be activated and deactivated via the SPI or I2C bus. Once the
interrupt has happened, the interrupt source can be read out from the corresponding status
register.
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1.2.7
Operational flow chart
CMA3000 power up
CMA3000 power down mode can
2
be activated via SPI/I C bus
CMA3000 in
power down mode
CMA3000 operation mode can be
2
changed via SPI/I C bus
Activate CMA3000 operation
2
mode via SPI/I C bus
Measurement mode
Free fall mode
Motion detection mode
Low pass filtered XYZ acceleration
data available
Low pass filtered XYZ acceleration
data available
Band pass filtered XYZ acceleration
data available
Ranges and data rates:
2g: 400Hz, 100Hz
8g: 400Hz, 100Hz, 40Hz
Ranges and data rates:
2g: 400Hz, 100Hz
8g: 400Hz, 100Hz
Ranges and data rates:
8g: 10Hz
INT-pin gives interrupt when
new data is available
INT-pin gives interrupt when
free fall is detected
INT-pin gives interrupt when
motion is detected
Additional configuration option:
• INT-pin data ready functionality can
be disabled
Additional configuration option:
• Free fall trigger conditions can be
configured (time & acceleration)
Additional configuration option:
• Motion detection trigger conditions
can be configured (time &
acceleration)
• CMA3000 can be configured to
switch to measurement mode with
400Hz output data rate after motion
is detected
CMA3000 operation in application
Figure 2. CMA3000 operational flow chart.
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2
Reset and power up, Operation Modes, HW functions and Clock
2.1
Reset and power up
The CMA3000 has internal power-on reset circuit. It releases the internal reset-signal once the
power supplies will be within the specified range.
After releasing the internal reset, the CMA3000 will read configuration and calibration data from the
non-volatile memory to volatile registers. Then the CMA3000 will make parity check to the read
memory content. The STATUS register's PERR-bit="0" shows successful memory read operation.
Device can be externally reset by writing the sequence 02h, 0Ah, 04h into the RSTR-register.
2.2
Power Down mode
The CMA3000-D0X enters the power down mode by default after power-on reset and initialization
of the volatile registers. PD can also be set by writing MODE[2:0] = 000b (or MODE[2:0] = 111b) to
CTRL register.
Output registers will keep their content in the power down mode.
2.3
2.3.1
Measurement Mode
Description
The CMA3000-D0X is set to a measurement mode by writing MODE[2:0] = 0XXb to CTRL register.
Data will be reliable in the output registers after the product specific turn-on time.
Default sample rate is 400 Hz (MODE[2:0] = 010b). Other data rates are 100 Hz (MODE[2:0] =
001b) and 40 Hz (MODE[2:0] = 011b).
Table 2. CMA3000-D0X measurement ranges and output sample rates
Measurement range
Output sample rates
2g
8g
400 Hz, 100 Hz
400 Hz, 100 Hz, 40 Hz
INT-pin gives an interrupt by default when new data is available.
2.3.2
Usage
Acceleration data can be read from data output registers DOUTX, DOUTY and DOUTZ. See
section 2.6 for INT-pin configuration details.
2.4
2.4.1
Motion Detection Mode
Description
In MD mode the device works at 10 Hz sample rate and the fixed measurement range is 8 g. Signal
is band pass filtered and fed to threshold level programmable digital comparator and a configurable
trigger function. Filtered signal is also available at output registers.
The device can be configured to switch automatically into the measurement mode with highest
sampling rate (400Hz) after motion is detected. The measurement range used will be defined by
G_RANGE bit.
Nominal BPF's -3 dB high-pass frequency is 1.3 Hz and -3 dB low-pass frequency is 3.8 Hz. See
Figure 3 below.
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Figure 3. The MD band-pass filter's frequency response.
Threshold level can be controlled by MDTHR[6:0] bits and the time condition – how long the
threshold should be exceeded to trigger – by MDTMR[3:0] bits.
Acceleration
X, Y or Z
Acceleration exceeds
the threshold level
due to motion ∆T
period of time
∆T
+TL
T1
T2
T3
T4
T5
T6
T7
T8
T1
T2
T3
T4
T5
T6
T7
T8
Time
-TL
INT output
"1"
"0"
Figure 4. Motion detector operation
2.4.2
Usage
The MD mode can be enabled by setting the MODE[2:0] bits in the MODE register to "100". The
trigger condition, threshold and duration, can be defined by setting MDTHR and MDFFTMR
registers respectively. The device can be configured to switch automatically into 400Hz
measurement mode by setting the MDET_EXIT bit in CTRL register. See section 3.3 register and
section 2.6 for the interrupt functionality details.
In MD mode, band pass filtered acceleration data with 10Hz output data rate is available in
registers DOUTX, DOUTY and DOUTZ.
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2.4.3
Example
Below is a simple example of motion detection usage:
1. Write "00001000" (08h) into the MODE register (enable motion detection mode, MODE[2:0]
bits = '100').
2. Band pass filtered acceleration data at 10 Hz sample rate is available at the output
registers.
3. The INT-pin is activated when motion is detected; see section 2.6 for detailed INT-pin
information.
2.5
2.5.1
Free-Fall Detection
Description
During free-fall in the gravitation field, all 3 orthogonal acceleration components are ideally equal to
zero. Due to practical non-idealities, detection must be done using Threshold Level (TL) greater
than 0.
When enabled, the Free-Fall Detection (FFD) will monitor the measured acceleration in the X, Y
and Z directions. If all measured XYZ acceleration values stay within the TL longer than time TFF
(Figure 5 below), the FFD will generate an interrupt to the INT-pin. TL can be controlled by FFTHR
[6:0] and TFF by FFTMR [3:0] bits.
Acceleration
X, Y and Z
+TL
T1
T2
T3
T4
T5
T6
T7
T8
Time
T6
T7
T8
Time
-TL
TFF
INT output
"1"
"0"
T1
T2
T3
T4
T5
Figure 5. Free Fall condition
2.5.2
Usage
Free-fall detection can be enabled by setting MODE[2:0] bits in the CTRL register to "101" (sample
rate 100 Hz) or to "110" (sample rate 400 Hz). See section 3.3 for MODE register details.
Acceleration data is available in registers DOUTX, DOUTY and DOUTZ as in measurement mode.
See section 3.3 for output register and section 2.6 for interrupt functionality details.
2.5.3
Example
Below is a simple example of free-fall detection usage:
1. Write "00001100" (0Ch) into the MODE register (enable 400 Hz free fall detection mode,
MODE[2:0] bits = '110').
2. Acceleration data can be read normally
3. INT-pin is activated when free fall is detected. See section 2.6 for detailed INT-pin
information.
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2.6
2.6.1
Interrupt function (INT-pin)
Usage
Depending on the CMA3000 operational configuration, the INT-pin can give an interrupt in following
cases:
1. Normal measurement mode: INT-pin gives interrupt when new data is available
2. Free fall detection mode: INT-pin gives an interrupt to signal that free fall is detected
3. Motion detection mode: INT-pin gives an interrupt to signal that motion is detected
Interrupt polarity (active high/low) can be configured with CTRL register's INT_LEVEL bit.
If the CMA3000 is in normal measurement mode, the INT pin is automatically cleared by reading
the acceleration output data. INT-pin data ready functionality can be disabled by setting the CTRL
register's INT_DIS bit.
If INT-pin gives an interrupt in free fall or motion detection mode, the INT_STATUS register must
be read to acknowledge and clear the interrupt.
In motion detection mode the INT_STATUS register content gives information of which XYZ
directions have exceed the trigger conditions.
See section 3.3 for CTRL and INT_STATUS register details.
2.7
Clock
The CMA3000 has an internal factory trimmed oscillator and clock generator. Internal frequencies
vary product by product.
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3
Addressing Space
The CMA3000 register contents and bit definitions are described in more detail in the following
sections.
3.1
Register Description
The CMA3000 addressing space is presented in Table 3 below.
Table 3. List of registers
Address
Mode
Name
Description
00h
WHO_AM_I
Identification register
R
01h
REVID
ASIC revision ID, fixed in metal
R
02h
CTRL
RW
03h
STATUS
Configuration (por, operation
modes)
Status (por, EEPROM parity)
04h
RSTR
Reset Register
RW
05h
INT_STATUS
Interrupt status register
06h
DOUTX
X channel output data register
R
07h
DOUTY
Y channel output data register
R
08h
DOUTZ
Z channel output data register
09h
MDTHR
0Ah
MDFFTMR
0Bh
FFTHR
Motion detection threshold value
register
Free fall and motion detection
time register
Free fall threshold value register
0Ch
I2C_ADDR
0Dh-19h
(R, RW, NV)
2
I C device address
Reg.
type
Output
Output
Conf
RW
Output
Conf
Output
Output
Output
Output
Conf
RW
Conf
RW
Conf
Conf
R
R
R
R
Reserved
Address is the register address in hex format.
RW – Read / Write register, R – Read-only register, NV – non-volatile register content.
3.2
Non-volatile memory
The CMA3000 has an internal non-volatile memory for calibration and configuration data. Memory
content will be programmed during production and is not user configurable. Initial configuration
values mirrored to volatile registers after reset can be found in the following section 3.3.
3.3
Registers
Address: 00h
Register name: WHO_AM_I, Identification register
Initial
Bits
Mode
Name
Description
Value
7
R
0
Reserved
6:0
R
xxh
Address: 01h
Register name: REVID, ASIC revision ID
Initial
Bits
Mode
Name
Value
7:4
R
1h
REVMAJ
3:0
R
0h
REVMIN
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Identification register
Description
Major revision number
Minor revision number (metal mask change)
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CMA3000-D0X Series
Address: 02h
Register name: CTRL, Control register
Initial
Bits
Mode
Name
Value
7
RW
0
G_RANGE
Description
0 – 8g measurement range is selected
1 – 2g measurement range is selected
6
RW
0
INT_LEVEL 0 – INT is active when INT pin is set to logic high
1 – INT is active when INT pin is set to logic low
5
RW
0
MDET_EXIT 0 – Device goes to measurement mode after motion
is detected (400Hz ODR)
1 – Device remains in motion detection mode after
motion is detected.
4
RW
0
I2C_DIS
0 – I2C interface enabled
1 – I2C interface disabled.
3:1
RW
0
MODE[2:0]
000 – Power down mode, default mode.
001 – Measurement mode, 100 Hz ODR.
010 – Measurement mode, 400 Hz ODR.
011 – Measurement mode, 40 Hz ODR.
100 – Motion detection mode, 10 Hz ODR.
101 – Free fall detection mode, 100 Hz ODR.
110 – Free fall detection mode, 400 Hz ODR.
111 – Power down mode
0
RW
0
INT_DIS
0 – Interrupts enabled
• Measurement mode: data ready
• Motion detection mode: motion detected
• Free fall detection mode: free fall detected
1 – Interrupts disabled
Note that after changing MODE bits it may take some time to recover the target operating state.
ODR = Output Data Rate.
Address: 03h
Register name: STATUS, Status register
Initial
Bits
Mode
Name
Value
7:4
0h
3
R
0
PORST
2:1
0
R
0h
0
PERR
Address: 04h
Register name: RSTR, Reset register
Initial
Bits
Mode
Name
Value
7:0
RW
0h
RSTR
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Description
Reserved
1 means Power-on-Reset state. Reading the register
sets always bit to 0.
Reserved
0 – No EEPROM Parity Error
1 – EEPROM Parity Error
Description
Writing 02h, 0Ah, 04h in this order resets ASIC.
Other sequences reserved.
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Address: 05h
Register name: INT_STATUS, Interrupt status register
Initial
Bits
Mode
Name
Description
Value
7:3
0h
Reserved
2
R
0
FFDET
1 – Free fall detected (i.e. 0 g acceleration)
0 – Free fall not detected
1:0
R
0h
MDET
00 – No motion detected
01 – Trigger on X-axis
10 – Trigger on Y-axis
11 – Trigger on Z-axis
Note: Contents of INT_STATUS [2:0] is set to '000' always after reading of this register.
Address: 06h
Register name: DOUTX, X-channel output register
Initial
Bits
Mode
Name
Description
Value
7:0
R
0h
DOUTX
See SPI data frame description for more info.
Address: 07h
Register name: DOUTY, Y-channel output register
Initial
Bits
Mode
Name
Description
Value
7:0
R
0h
DOUTY
See SPI data frame description for more info.
Address: 08h
Register name: DOUTZ, Z-channel output register
Initial
Bits
Mode
Name
Description
Value
7:0
R
0h
DOUTZ
See SPI data frame description for more info.
The bit level description for acceleration data from DOUTX ... DOUTZ registers is presented in
Table 4 below. The acceleration data is presented in 2's complement format. At 0 g acceleration
the output is ideally 0h.
Table 4. Bit level description in [mg] for acceleration registers of CMA3000-D01.
Range
G_RANGE
2g
2g
8g
8g
1
1
0
0
Output sample
B7 B6
B5
B4
rate
400 Hz, 100 Hz s 1142 571 286
40 Hz, 10 Hz
s 4571 2286 1142
400 Hz, 100 Hz s 4571 2286 1142
40 Hz, 10 Hz
s 4571 2286 1142
B3
B2
B1
B0
143
571
571
571
71
286
286
286
36
143
143
143
1/56 = 18 mg
1/14 = 71 mg
1/14 = 71 mg
1/14 = 71 mg
s = sign bit
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Address: 09h
Register name: MDTHR, Motion detection threshold value register
Initial
Bits
Mode
Name
Description
Value
Reserved
7
0
6:0
RW
8h
MDTHR[6:0] Motion detection threshold level absolute value. See
detailed bit level weighting in Table 5 (bits [6:0])
Table 5. Bit level description in [mg] for motion detection threshold of CMA3000-D01.
G_RANGE
0
Range
8g
B7
x
B6
4571
B5
2286
B4
1142
B3
571
B2
286
B1
143
B0
1/14 = 71 mg
x=not used bit
Address: 0Ah
Register name: MDFFTMR, Motion and free fall detection time register
Initial Value
Bits
Mode
Name
Description
Motion detection timer bits
7:4
RW
3h
MDTMR[3:0]
3:0
RW
3h
FFTMR [3:0]
Free fall detection timer bits
The LSB bit weighting for MDTMR and FFTMR bits are converted to seconds by using the currently
configured CMA3000 output data rate (ODR), as follows:
MDTMRLSB[sec] = 1 / ODR[Hz], and
FFTMRLSB[sec] = 1 / ODR[Hz]
Were the ODR is the currently configured CMA3000 output data rate, which is defined by MODE
bits (bits [3:1] in CTRL register). An example for CMA3000-D01 timer bit weighting is presented in
Table 6 below.
Table 6. An example for CMA3000-D01 MDTMR and FFTMR bit level descriptions in [ms].
Timer
Register bit number
Timer bit number
CMA3000-D01,
MODE bits x10
ODR: 400Hz
CMA3000-D01,
MODE bits x01
ODR: 100Hz
CMA3000-D01,
MODE bits 100
ODR: 10Hz
MDTMR
FFTMR
B7
B6
B5
B4
B3
B2
B1
B0
MDTMR
b3
MDTMR
b2
MDTMR
B1
MDTMR
b0
FFTMR
b3
FFTMR
b2
FFTMR
B1
FFTMR
b0
x
x
x
x
20
10
5
1/400s =
2,5 ms
x
x
x
x
80
40
20
1/100s =
10 ms
x
400
200
1/10s =
100 ms
x
x
x
x
x=not used bit
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Address: 0Bh
Register name: FFTHR, Free fall threshold value register
Initial
Bits
Mode
Name
Description
Value
Reserved, write these bits to '000'
7:5
0h
4:0
RW
8h
FFTHR[5:0] Free fall detection threshold level absolute value. See
detailed bit level weighting in Table 7 below.
Table 7. Bit level description in [mg] for free fall detection threshold of CMA3000-D01.
Range
2g
8g
G_RANGE
1
0
B5
143
x
B4
71
x
B3
36
571
B2
1/56=18 mg
286
B1
x
143
B0
x
1/14 = 71 mg
x=not used bit
Address: 0Ch
Register name: I2C_ADDR, Device address for I2C bus
Initial
Bits
Mode
Name
Description
Value
Reserved
7
0
6:0
RW
1Ch
ADDR[6:0]
7-bit device address for I2C bus. Register content is
non-volatile.
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4
Serial Interfaces
Communication between the CMA3000 sensor and master controller is based on serial data
transfer and a dedicated interrupt line (INT-pin). Two different serial interfaces are available for the
CMA3000 sensor: SPI and I2C (Phillips specification V2.1). Selection between these two interfaces
is done using the chip select signal. The I2C interface can be also disabled by re-configuring
register content. The CMA3000 acts as a slave on both the SPI and I2C bus.
4.1
SPI Interface
SPI bus is a full duplex synchronous 4-wire serial interface. It consists of one master device and
one or more slave devices. The master is defined as a micro controller providing the SPI clock, and
the slave as any integrated circuit receiving the SPI clock from the master. The CMA3000 sensor
always operates as a slave device in master-slave operation mode. A typical SPI connection is
presented in Figure 6.
MASTER
MICROCONTROLLER
SLAVE
DATA OUT (MOSI)
SI
DATA IN (MISO)
SO
SERIAL CLOCK (SCK)
SCK
SS0
CS
SS1
SI
SS2
SO
SS3
SCK
CS
SI
SO
SCK
CS
SI
SO
SCK
CS
Figure 6. Typical SPI connection
The data transfer uses the following 4-wire interface:
MOSI
MISO
SCK
CSB
4.1.1
µC → CMA3000
CMA3000 → µC
µC → CMA3000
µC → CMA3000
master out slave in
master in slave out
serial clock
chip select (low active)
SPI frame format
CMA3000 SPI frame format and transfer protocol is presented in Figure 7.
CSB
1
SCK
MOSI
MISO
A5
2
A4
3
A3
4
A2
5
A1
6
A0
PORST
7
RB/W
8
9
10
11
12
13
14
15
16
DI7
DI6
DI5
DI4
DI3
DI2
DI1
DI0
DO7
DO6
DO5
DO4
DO3
DO2
DO1
DO0
Figure 7. SPI frame format
Each communication frame contains 16 bits. The first 8 bits in MOSI line contains info about the
register address being accessed and the operation (read/write). The first 6 bits define the 6 bit
address for the selected operation, which is defined by bit 7 (‘0’ = read ‘1’ = write), which is
followed by one zero bit. The later 8 bits in the MOSI line contain data for a write operation and are
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‘don’t-care’ for a read operation. CMA3000 samples bits in from MOSI line on the rising edge of
SCK and bits out to MISO line on falling edge of SCK.
After the two constant '0' bits in the MISO line are the PORST status bits. All three PORST status
bits have the same value as the PORST bit in register STATUS. Bits 6 and 8 are always '0'. Bit 7 is
always ‘1’. The later 8 bits contain data for a read operation.
For write commands, data is written into the addressed register after the rising edge of CSB.
For read commands, data is latched into the internal SPI output register (shift register) on the 8th
rising edge of SCK. The output register is shifted out MSB first over MISO output.
When the CSB is high state between data transfers, the MISO line is in the high-impedance state.
4.1.2
4.1.2.1
Examples of SPI communication
Example of register read
An example of X-axis and Y-axis acceleration read command is presented in Figure 8. The master
gives the register address to be read via the MOSI line: '06' in hex format and '000110' in binary
format, register name is DOUTX). 7th bit is set to '0' to indicate the read operation.
The sensor replies to a requested operation by transferring the register content via MISO line. After
transferring the asked DOUTX register content, the master gives next register address to be read:
'07' in hex format and '000111' in binary format, register name is DOUTY. The sensor replies to the
requested operation by transferring the register content MSB first.
CSB
MISO
PORST
DX5
DX4
DX3
DX2
DX1
LSB DX0
0 0 0 1 1 1 0
PORST
MSB DX7
DX6
0 0 0 1 1 0 0
MSB DY7
DY6
DY5
DY4
DY3
DY2
DY1
LSB DY0
SCLK
MOSI
Figure 8. An example of SPI read communication.
4.1.3
Multiple slave devices in SPI bus
Since both SPI and I2C interfaces are enabled by default, certain precautions should be taken care
of when the CMA3000 is connected to a SPI bus with multiple slave devices. In case of multiple
devices on same SPI bus, it's important to prevent MOSI_SDA pin changes during SCK_SCL pin
high state. If the MOSI_SDA pin state is changed when the SCK_SCL pin is in high state, the I2C
transmission is engaged, see Figure 9 below.
Figure 9. MOSI_SDA pin change during SCK_SCL high state engages I2C transmission.
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In cases with multiple slaves in SPI bus it is recommended that I2C transmission is disabled by
setting I2C_DIS bit to '1' in CRTL register. After CMA3000 start up the I2C_DIS bit is always 0 (I2C
transmission enabled).
4.2
I2C Interface
I2C is a 2-wire serial interface. It consists of one master device and one or more slave devices. The
master is defined as a micro controller providing the serial clock (SCL), and the slave as any
integrated circuit receiving the SCL clock from the master. The CMA3000 sensor always operates
as a slave device in master-slave operation mode. When using an SPI interface, a hardware
addressing is used (slaves have dedicated CSB signals), the I2C interface uses a software based
addressing (slave devices have dedicated bit patterns as addresses). The default I2C device
address for CMA3000 is 00011100b (1Ch) (pre-programmed during CMA3000 production).
The CMA3000 is compatible to the Philips I2C specification V2.1. Main used features of the I2C
interface are:
- 7-bit addressing, CMA3000 I2C device address is 1Ch
- Supports standard mode and fast mode
- Start / Restart / Stop
- Slave transceiver mode
- Designed for low power consumption
4.2.1
4.2.1.1
I2C frame format
I2C write mode
In I2C write mode, the first 8 bits after device address define the CMA3000 internal register address
to be written.
4.2.1.2
I2C read mode
The read mode operates as described in Philips I2C specification. I2C read operation returns the
content of the register which address is defined in I2C read frame. Read data is acknowledged by
I2C master.
4.2.2
Examples of I2C communication
Examples of I2C communication are presented below in Figure 10. Address byte includes 7 device
address bits (1Ch=0011100b) followed by the R/W bit.
Figure 10 I2C format
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5
Electrical Characteristics
All voltages are reference to ground. Currents flowing into the circuit have positive values.
5.1
Absolute maximum ratings
The absolute maximum ratings of the CMA3000 are presented in Table 8 below.
Table 8. Absolute maximum ratings of the CMA3000
Parameter
Supply voltage (Vdd, DVIO)
DVIO
Voltage at input / output pins
ESD (Human body model)
Storage temperature
Storage / operating temperature
Mechanical shock *
Exposure to ultrasonic energy
(e.g. ultra sonic washing or
welding)
Value
-0.3 to +3.6
Vdd+0.2
-0.3 to (Vdd + 0.3)
±2
-40 ... +125
-40 ... +85
< 10 000
Unit
V
V
V
kV
°C
°C
g
Not allowed
* 1 m drop on concrete may cause >>10000 g shock.
5.2
Power Supply
Please refer to the corresponding product datasheet.
5.3
5.3.1
Digital I/O Specification
Digital I/O DC characteristics
Table 9. DC characteristics of digital I/O pins.
No. Parameter
Conditions
Input: CSB, SCL with pull up
SDA, SCK and MOSI without pull up / pull down
Pull up current:
VIN = 0V
2
CSB, SCL
VIN = DVIO
2a. Input Leakage
Input high voltage
3
Input low voltage
4
Hysteresis
5
Output terminal: MISO, SDA, INT
Output high voltage
I > -1 mA
7
Output low voltage
I < 1 mA
8
Tristate leakage
0 < VMISO < DVIO
9
5.3.2
Symbol
Min
IPU
-0.35
IIN
VIH
VIL
VHYST
0.54*Dvio
0.18*Dvo
0.16*Dvio
VOH
VOL
ILEAK
0.7*Dvio
0
Typ
Max
Unit
µA
0.035
0.82*Dvio
0.38*Dvio
0.63*Dvio
µA
V
V
V
Dvio
0.3*Dvio
0.0063
V
V
µA
Digital I/O level shifter
All the CMA3000 products have an internal level shifter that can be used to interface e.g. a micro
controller using lower supply than the CMA3000. The level shifter is "programmed" by providing the
supply voltage of the interfaced device to the DVIO-pin. Please refer to the corresponding product
data sheet for details.
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5.3.3
SPI AC characteristics
The AC characteristics of the CMA3000 SPI interface are defined in Figure 11 and in Table 10.
TLS1
TCH
TCL
TLS2
TLH
CSB
SCK
THOL
MOSI
TSET
MSB in
TVAL1
MISO
DATA in
LSB in
TVAL2
TLZ
MSB out
DATA out
LSB out
Figure 11. Timing diagram for SPI communication.
Table 10. AC characteristics of SPI communication.
No.
Parameter
Conditions
Symbol
Min
TLS1
0.80*
Tper/2
0.80*
Tper/2
Typ
Max
Unit
Terminal CSB, SCK
1
2
Time from CSB (10%) to
(1
SCK (90%)
Time from SCK (10%) to
(1
CSB (90%)
TLS2
ns
ns
Terminal SCK
3
SCK low time
4
SCK high time
5
SCK Frequency
Load capacitance
at MISO < 50 pF
Load capacitance
at MISO < 50 pF
TCL
TCH
0.80*
Tper/2
0.80*
Tper/2
Tper/2
ns
Tper/2
ns
0.5
fsck =
1/Tper
MHz
Terminal MOSI, SCK
6
7
Time from changing MOSI
(10%, 90%) to SCK (90%)
Data setup time
Time from SCK (90%) to
changing MOSI (10%, 90%)
Data hold time
TSET
Tper/4
ns
THOL
Tper/4
ns
Terminal MISO, CSB
8
9
Time from CSB (10%) to
stable MISO (10%, 90%)
Time from CSB (90%) to
high impedance state of
(1
MISO .
Load capacitance
at MISO < 50 pF
Load capacitance
at MISO < 50 pF
TVAL1
Tper/4
ns
TLZ
Tper/4
ns
Load capacitance
at MISO < 50 pF
TVAL2
1.5*Tper/4
ns
Terminal MISO, SCK
10
Time from SCK (10%) to
(1
stable MISO (10%, 90%) .
Terminal MOSI, CSB
11
Time between SPI cycles,
CSB at high level (90%)
1)
Tper is SCK period
5.3.4
TLH
11 * Tper
ns
I2C AC characteristics
Please, see Phillips Semiconductors, The I2C bus specification, Version 2.1, January 2000, pp. 3133.
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6
6.1
Package Characteristics
Dimensions
The package dimensions are presented in Figure 12 below (dimensions in millimeters [mm] with
±50 µm tolerance).
Figure 12. Package dimensions in mm with ±50 µm tolerance for reference only. Please check the
corresponding data sheet for details.
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7
Application information
7.1
Pin Description
CMA3000 pin numbers are presented in Figure 14 below and pin descriptions in Table 11.
Z
X
Y
Figure 13. CMA3000 sensing directions
Figure 14. CMA3000 pin numbers
Table 11. CMA3000 pin descriptions
Pin #
1
2
3
4
5
6
7
8
7.2
Name
CMA3000-D01
VDD
VSS
DVIO
MISO
SCK_SCL
MOSI_SDA
CSB
INT
Supply voltage
Ground
I/O Supply
SPI Serial Data Output (MISO)
SPI Serial Clock (SCK) / I2C Serial Clock (SCL)
SPI Serial Data Input (MOSI) / I2C Serial Data (SDA)
Chip select / I2C enable
Interrupt
Recommended circuit diagram
1. Connect 100 nF SMD capacitor between each supply voltage and ground level.
2. Use separate regulator for digital IO supply (DVIO).
3. Serial interface (SPI or I2C) logical '1' level is determined by DVIO supply voltage level.
Recommended circuit diagram for the CMA3000 with SPI interface is presented in Figure 15 below.
I2C
SPI
1
VDD
2
3
DVIO
4
MISO
100n
VDD
VSS
DVIO
MISO
INT
CSB
MOSI_SDA
SCK_SCL
8
7
6
5
INT
1
VDD
2
CSB
3
MOSI DVIO
4
SCK
100n
100n
VDD
VSS
DVIO
MISO
INT
CSB
MOSI_SDA
SCK_SCL
8
INT
7
6
5
SDA
SCL
100n
Figure 15 Recommended circuit diagrams for CMA3000-D0X
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7.3
Recommended PWB layout
General PWB layout recommendations for CMA3000 products (refer to Figure 15 and Figure 16):
1. Locate 100 nF SMD capacitors right next to the CMA3000 package
2. Ensure low impedance by maximizing the ground plane under the component.
Recommended PWB pad layout for CMA3000 is presented in Figure 16 below (dimensions in
micrometers, [µm]).
Figure 16. Recommended PWB pad layout for CMA3000.
Recommended PWB layout for the CMA3000-D0X is presented in Figure 17 below (circuit diagram
presented in Figure 15 above).
Note the symmetrical
ground plane under the
component.
Figure 17. Recommended PWB layout for CMA3000-D0X with SPI interface (not
actual size, for reference only).
7.4
Mounting recommendations
For the best sensor stability mechanical stresses due to mounting should be minimized. Potential
causes of mechanical stress to be avoided are
•
•
•
•
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Placement under or next to mechanical push button contacts.
Locations near hot spots (micro controller, power amplifier etc) due to temperature effects.
Mounting close to PWB attachment point e.g. screw or snap.
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•
•
PWB areas that can bend or vibrate.
The use of under fill or coating. Please note that under fill or coating the neighboring
component should not be in contact with the sensor.
Due to sampled signal conditioning strong magnetic or electric fields may cause noise in the sensor
output. Therefore mounting near strong magnetic or electric fields is not recommended.
7.5
Assembly instructions
The Moisture Sensitivity Level (MSL) of the CMA3000 component is 2 according to the IPC/JEDEC
J-STD-020D. Please refer to the document TN68_CMA3000_Assembly_Instructions for more
detailed information about CMA3000 assembly.
7.6
Tape and reel specifications
Please refer to the document TN68_CMA3000_Assembly_Instructions for tape and reel
specifications.
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8
Data sheet references
8.1
Offset
CMA3000's offset will be calibrated in X = 0 g, Y = 0 g, and Z = +1 g (Z measuring axis is parallel to
earth’s gravitation) position, see Figure 18.
Z-axis in +1 g
position
Y
Earth’s
gravitation
X
Pin #1
Figure 18. CMA3000 offset (0 g) position.
8.1.1
Offset calibration error
Offset calibration error is the difference between the sensor's actual output reading and the nominal
output reading in calibration conditions. Error is calculated by
Equation 1
Offset X −axisCalibEr =
Output X −axis − Output
⋅ 1000 ,
Sens
where OutputX-axisCalibEr is sensor’s X-axis calibration error in [mg], OutputX-axis is sensor’s X-axis
output reading [counts], Output is sensor’s nominal output in 0 g position and Sens sensor’s nominal
sensitivity [counts/g].
8.1.2
Offset temperature error
Offset temperature error is the difference between the sensor's output reading in different
temperatures and the sensor’s calibrated offset value at room temperature. Error is calculated by
Equation 2
Offset X − axisTempEr @ T =
Output X − axis @ T − Output X − axis @ RT
Sens
⋅1000 ,
where OutputX-axisTempEr@T is sensor’s X-axis temperature error in [mg] in temperature T, OutputX-axis@T
is sensor’s X-axis output reading [counts] in temperature T, OutputX-axis@T X-axis output reading
[counts] at room temperature RT and Sens sensor’s nominal sensitivity [counts/g]. Sensor is in 0 g
position for every measurement point.
8.2
Sensitivity
During sensitivity calibration, the sensor is placed in ±1 g positions having one of the sensor’s
measuring axes at a time parallel to the earth’s gravitation, see Figure 19.
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Pin #1
Z
Y-axis in +1 g
position
X
Earth’s
gravitation
X
Z
Y-axis in -1 g
position
Pin #1
Figure 19. CMA3000 positions for Y-axis sensitivity measurement.
Sensitivity is calculated by
Equation 3
SensY − axis =
OutputY − axis @ +1g − OutputY − axis @ −1g
2g
,
where SensY-axis is sensor’s Y-axis sensitivity in [counts/g], OutputY-axis@+1g sensor’s Y-axis output
reading [counts] in +1 g position and OutputY-axis@-1g is sensor’s Y-axis output reading [counts] in -1 g
position.
8.2.1
Sensitivity calibration error
Sensitivity calibration error is the difference between sensor’s measured sensitivity and the nominal
sensitivity at room temperature conditions. Error is calculated by
Equation 4
SensY − axisCalibE r =
SensY − axis − Sens
⋅100% ,
Sens
where SensY-axisCalibEr is sensor’s Y-axis sensitivity calibration error in [%], SensY-axis sensor’s Y-axis
sensitivity [counts/g] at room temperature conditions and Sens is sensor’s nominal sensitivity
[counts/g].
8.2.2
Sensitivity temperature error
Sensitivity temperature error is the difference between sensor’s sensitivity at different temperatures
and the calibrated sensitivity. Error is calculated by
Equation 5
SensY − axisTempEr @T =
SensY − axis @ T − SensY − axis @ RT
SensY − axis @ RT
⋅100% ,
where SensY-axisTempEr@T is sensor’s Y-axis sensitivity temperature error in [%] in temperature T, SensYaxis@T is sensor’s measured Y-axis sensitivity [counts/g] at temperature T and SensY-axis@RT is sensor’s
measured Y-axis sensitivity [counts/g] at room temperature RT.
8.3
Linearity
The needed accurate input acceleration in linearity characterization is generated using centrifugal
force in centrifuge, see Figure 20. The RPM of the centrifuge is swept so that wanted input
acceleration values are applied in parallel to the sensor’s measuring axis.
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X
Z
Centrifugal
acceleration
for Z-axis
Y
Pin #1
Figure 20. Centrifugal acceleration applied for CMA3000 Z-axis.
Linearity error is the deviation from the best bit straight line. See Figure 21.
Acceleration reading
from CMA3000 [g]
CMA3000 linearity
error in [g] at input
acceleration acc
-FS
+FS
acc
CMA3000 output
readings
Sensor’s ideal
output
Input acceleration [g] (centrifugal
acceleration in parallel to
CMA3000 measuring axis)
Possible offset error is not
included into linearity error
Figure 21. CMA3000’s linearity error at input acceleration acc.
Linearity error is calculated by
Equation 6
LinErZ −axis @ acc =
Output Z −axis @ acc − Output@ acc
Sens ⋅ FS
⋅100% ,
where LinErZ-axis@acc is sensor’s Z-axis linearity error [%FS] on input acceleration acc, OutputZ-axis@acc
is sensor’s measured Z-axis output [counts] on input acceleration acc, Output@acc is sensor’s
nominal output [counts] on input acceleration acc, Sens is sensor’s nominal sensitivity [counts/g] and
FS is sensor’s full scale measuring range [g] (for example for CMA3000-D01 with ±2g setting →
FS = 2 g).
Sensor’s ideal output Output@acc (in Equation 6) is calculated by fitting a straight line to measured
accelerations from –FS to FS.
8.4
Noise
Output noise nX, nY and nZ in X,Y and Z directions is the measured standard deviation of the output
values when the sensor is in 0 g position at room temperature. Average noise/axis is calculated by
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Equation 7
n=
(
)
1 2
n X + nY2 + nZ2 ,
3
where n is sensor’s noise [g] per axis, nX is sensor’s X-axis noise [g], nY is sensor’s Y-axis noise [g]
and nZ is sensor’s Z-axis noise [g].
CMA3000 demo-kit design can be used as a reference design for noise measurements, refer to
“CMA3000 DEMO KIT User Manual 8288400”.
8.5
Bandwidth
Signal bandwidth is measured in a shaker by sweeping the piston movement frequency with
constant amplitude (Figure 22).
Z
Y
X
Shaker
movement
in parallel
to Z-axis
Earth’s
gravitation
Pin #1
Figure 22. CMA3000 movement in Z-axis bandwidth measurement.
8.6
Cross-axis sensitivity
Cross-axis sensitivity is sum of the alignment and the inherent sensitivity errors. Cross-axis
sensitivity of one axis is a geometric sum of the sensitivities in two perpendicular directions.
Cross-axis sensitivity [%] of X-axis is given by
Equation 8
S XY + S XZ
⋅ 100%,
Cross X = ±
SX
2
2
where SXY is X-axis sensitivity to Y-axis acceleration [Count/g], SXZ is X-axis sensitivity to Z-axis
acceleration [Count/g] and SX is sensitivity of X-axis [Count/g].
Cross-axis sensitivity [%] of Y-axis is given by
Equation 9
S + SYZ
CrossY = ± YX
⋅100%,
SY
2
2
where SYX is Y-axis sensitivity to X-axis acceleration [Count/g], SYZ is Y-axis sensitivity to Z-axis
acceleration [Count/g] and SY is sensitivity of Y-axis [Count/g].
Cross-axis sensitivity [%] of Z-axis is given by
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Equation 10
S + S ZY
⋅ 100%,
Cross Z = ± ZX
SZ
2
2
where SZX is Z-axis sensitivity to X-axis acceleration [Count/g], SZY is Z-axis sensitivity to Y-axis
acceleration [Count/g] and SZ is sensitivity of Z-axis [Count/g].
Cross-axis sensitivity of CMA3000 family is measured in centrifuge over specified measurement
range during qualification. Correct mounting position of component is important during the
measurement of cross-axis sensitivity.
8.7
Turn-on time
Turn-on time is the time when the last of one X, Y, Z axis output readings stabilizes into its final
value after XRESET is pulled high. The final value limits in turn-on time measurements is defined to
be ±1 % of the sensor’s full scale measuring range (for example for CMA3000-D01 ±2g →
FS = 2 g). Turn-on time definition for Z-axis is presented in Figure 23 below.
Acceleration
Supply voltage reaches the
minimum required level
→ CMA3000 starts
CMA3000 output
inside ±1% FS
limits
CMA3000
Z-axis output
Time scale
Turn on time
Figure 23. Turn-on time definition for one axis.
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9
Known issues
9.1
Acceleration data reading via I2C bus
CMA3000-D01 has a design issue (to be corrected) related to acceleration data reading via I2C
bus: acceleration data reading during the INT-pin assertion (i.e. internal output register update)
causes the data corruption. The following sections discuss how to overcome this.
9.1.1
Interrupt based acceleration reading
Interrupt (INT-pin) based acceleration data reading can be used only in measurement mode. After
interrupt signal activation the acceleration data has to be read before next interrupt activation. The
allowed reading time depends on selected measurement mode. Detailed timing values are
presented in Table 12 and Figure 24 below.
Table 12. CMA3000-D01 maximum reading periods in interrupt based acceleration data reading.
Output data rate
CMA3000-D01, MODE bits x10
ODR: 400Hz
CMA3000-D01, MODE bits x01
ODR: 100Hz
CMA3000-D01, MODE bits 011
ODR: 40Hz
Maximum reading
period, Tr
2.25 ms
9.0 ms
22.5 ms
ODR = Output Data Rate
Interrupt activation
Acceleration reading ends
Interrupt activation
INT-pin
Reading period, Tr
Interrupt initialized
Figure 24. Interrupt based CMA3000 acceleration data read timing.
If the above presented data read timing constraints are not met, the acceleration output data
should be ignored. Valid data samples can be read after the next interrupt signal.
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9.1.2
Acceleration reading without interrupts
Acceleration data reading without interrupts can be used in all operation modes. Acceleration data
is read out faster than CMA3000 can updates the acceleration output registers. When two identical
XYZ acceleration values are received, the data is considered valid. The maximum data reading
periods in different operation modes are presented below in Table 13.
Table 13. CMA3000-D01 maximum reading periods when interrupts are not detected.
Output data rate
CMA3000-D01, MODE bits x10
ODR: 400Hz
CMA3000-D01, MODE bits x01
ODR: 100Hz
CMA3000-D01, MODE bits 011
ODR: 40Hz
CMA3000-D01, MODE bits 100
ODR: 10Hz
Maximum reading period
for 3 samples, Tr
2.4 ms
9.9 ms
24.0 ms
90.0 ms
ODR = Output Data Rate
Internal acceleration
register update
Acceleration reading
→ corrupted
These two acceleration readings result identical
acceleration values → This result is accepted
Acceleration reading
Acceleration reading
Internal acceleration
register update
Acceleration reading
→ corrupted
Acceleration data reading period for 3 samples, Tr
Figure 25. Interrupt based CMA3000 acceleration data read timing.
9.2
Leakage current when VDD - DVIO > 0.3 V
Due to design issue a switch will leak some current, if the VDD will be approx 300 mV higher than
DVIO. Typical leakage currents are according to the Table 14 below.
Table 14 CMA3000-D0X typical DVIO leakage current when VDD-DVIO>0.3V.
VDD/DVIO [V]
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Leakage current [µA]
2.5 / 1.7
25
3.6 / 1.7
100
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10 Order Information
Order code
Description
CMA3000-D01-1
CMA3000-D01-10
CMA3000-D01-30
CMA3000-D01 PWB
CMA3000-D01DEMO
3-Axis accelerometer with SPI&I2C interface, +/- 2/8g, 100 pcs
3-Axis accelerometer with SPI&I2C interface, +/- 2/8g, 1000 pcs
3-Axis accelerometer with SPI&I2C interface, +/- 2/8g, 3000 pcs
PWB assy 3-Axis accelerometer with SPI&I2C interface, +/- 2/8g
CMA3000-D01 DEMOKIT
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Packing
T&R
T&R
T&R
Bulk
Bulk
Quantity
100
1000
3000
1
1
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CMA3000-D0X Series
11 Document Change Control
Version
Date
Change Description
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10
06-Sep-07
11-Jan-08
14-Feb-08
18-Apr-08
01-Jul-08
29-Aug-08
10-Dec-08
29-Dec-08
28-Jan-09
02-Mar-09
Initial draft.
Major update.
Minor updates, corrections
Minor updates, section 'Known issues' added
Figure 1,&12 updated, table 9 updated
0.11
08-Jun-09
0.12
12-Jun-09
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Sensitivities from 1/60 and 1/15 counts/g updated to 1/56 and 1/14 counts/g
Figure 12 updated. Tables 4, 5, 7, 9, 10 updated. Sections 9.2 and 9.3 added.
Launch version. Table 6 updated.
Table 5, 7 & 10 updated.
2
Typo corrections, 3.3 register initial values updated, 4.2 I C address updated, 8.4 demo kit
document number updated, preliminary tag removed, MSL level 3 -> 2, 7.2 removed reference to
1uF capacitor
2
Figure 4 updated, 4.2.2 I C address byte description updated
Mounting recommendations (section 7.4) added.
Device bandwidth updated to ODR/5
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12 Contact Information
Finland
(head office)
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Finland
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Bureau Toranomon 401
105-0001
Japan
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Fax +81 3 6277 6619
E-mail: [email protected]
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201203 Shanghai
P.R. China
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Fax +86 21 513 20 416
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USA
VTI Technologies, Inc.
One Park Lane Blvd.
Suite 804 - East Tower
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USA
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Fax +1 313 425 0860
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