Analog Devices Semiconductor Electronic Components Datasheet



ADXL313 (Analog Devices)
Digital Accelerometer

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Data Sheet
3-Axis, ±0.5 g/±1 g/±2 g/±4 g
Digital Accelerometer
ADXL313
FEATURES
GENERAL DESCRIPTION
Ultralow power (scales automatically with data rate)
The ADXL313 is a small, thin, low power, 3-axis accelerometer
As low as 30 µA in measurement mode (VS = 3.3 V)
with high resolution (13-bit) measurement up to ±4 g. Digital
As low as 0.1 µA in standby mode (VS = 3.3 V)
output data is formatted as 16-bit twos complement and is
Low noise performance
accessible through either a serial port interface (SPI) (3-wire or
150 μg/√Hz typical for X- and Y-axes
4-wire) or I2C digital interface.
250 μg/√Hz typical for the Z-axis
Embedded, patent pending FIFO technology minimizes host
processor load
User-selectable resolution
Fixed 10-bit resolution for any g range
Fixed 1024 LSB/g sensitivity for any g range
Resolution scales from 10-bit at ±0.5 g to 13-bit at ±4 g
Built-in motion detection functions for activity/inactivity
monitoring
Supply and I/O voltage range: 2.0 V to 3.6 V
SPI (3-wire and 4-wire) and I2C digital interfaces
Flexible interrupt modes mappable to two interrupt pins
Measurement range selectable via serial command
Bandwidth selectable via serial command
Wide temperature range (−40°C to +105°C)
The ADXL313 is well suited for car alarm or black box applications.
It measures the static acceleration of gravity in tilt-sensing applica-
tions, as well as dynamic acceleration resulting from motion or
shock. Its high resolution (1024 LSB/g) and low noise (150 μg/√Hz)
enable resolution of inclination changes of as little as 0.1°. A built-
in FIFO facilitates using oversampling techniques to improve
resolution to as little as 0.025° of inclination.
Several built-in sensing functions are provided. Activity and
inactivity sensing detects the presence or absence of motion and
whether the acceleration on any axis exceeds a user-set level.
These functions can be mapped to interrupt output pins. An
integrated 32-level FIFO can be used to store data to minimize
host processor intervention, resulting in reduced system power
consumption.
10,000 g shock survival
Pb free/RoHS compliant
Small and thin: 5 mm × 5 mm × 1.45 mm LFCSP package
Qualified for automotive applications
APPLICATIONS
Low power modes enable intelligent motion-based power
management with threshold sensing and active acceleration
measurement at extremely low power dissipation.
The ADXL313 is supplied in a small, thin 5 mm × 5 mm ×
1.45 mm, 32-lead LFCSP package and is pin compatible with
Car alarms
the ADXL312 accelerometer device.
Hill start aid (HSA) systems
Electronic parking brakes
Data recorders (black boxes)
FUNCTIONAL BLOCK DIAGRAM
VS VDD I/O
ADXL313
POWER
MANAGEMENT
3-AXIS
SENSOR
SENSE
ELECTRONICS
ADC
DIGITAL
FILTER
CONTROL
AND
INTERRUPT
LOGIC
INT1
INT2
32-LEVEL
FIFO
SERIAL I/O
SDA/SDI/SDIO
SDO/ALT
ADDRESS
SCL/SCLK
GND
CS
Figure 1.
Rev. 0
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ADXL313
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications....................................................................................... 1
General Description ......................................................................... 1
Functional Block Diagram .............................................................. 1
Revision History ............................................................................... 2
Specifications..................................................................................... 3
Absolute Maximum Ratings............................................................ 4
Thermal Resistance ...................................................................... 4
ESD Caution.................................................................................. 4
Pin Configuration and Function Descriptions............................. 5
Typical Performance Characteristics ............................................. 6
Theory of Operation ........................................................................ 8
Power Sequencing ........................................................................ 8
Power Savings ............................................................................... 8
Serial Communications ................................................................. 10
SPI................................................................................................. 10
I2C ................................................................................................. 13
Interrupts..................................................................................... 15
REVISION HISTORY
4/13—Revision 0: Initial Version
Data Sheet
FIFO ............................................................................................. 15
Self Test ........................................................................................ 16
Register Map ................................................................................... 17
Register Definitions ................................................................... 18
Applications Information .............................................................. 22
Power Supply Decoupling ......................................................... 22
Mechanical Considerations for Mounting.............................. 22
Threshold .................................................................................... 22
Link Mode ................................................................................... 22
Sleep Mode vs. Low Power Mode............................................. 22
Using Self Test............................................................................. 23
3200 Hz and 1600 Hz ODR Data Formatting ........................ 24
Axes of Acceleration Sensitivity ............................................... 25
Solder Profile................................................................................... 26
Outline Dimensions ....................................................................... 27
Ordering Guide .......................................................................... 28
Automotive Products ................................................................. 28
Rev. 0 | Page 2 of 28


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Data Sheet
ADXL313
SPECIFICATIONS
TA = −40°C to +105°C, VS = VDD I/O = 3.3 V, acceleration = 0 g, unless otherwise noted.
Table 1.
Parameter 1
SENSOR INPUT
Measurement Range
Nonlinearity
Micro-Nonlinearity
Interaxis Alignment Error
Cross-Axis Sensitivity2
OUTPUT RESOLUTION
All g Ranges
±0.5 g Range
±1 g Range
±2 g Range
±4 g Range
SENSITIVITY
Sensitivity at XOUT, YOUT, ZOUT
Sensitivity Change Due to Temperature
0 g BIAS LEVEL
Initial 0 g Output
0 g Output Drift over Temperature
0 g Offset Tempco
NOISE PERFORMANCE
Noise Density
RMS Noise
OUTPUT DATA RATE/BANDWIDTH
Measurement Rate3
SELF TEST4
Output Change in X-Axis
Output Change in Y-Axis
Output Change in Z-Axis
POWER SUPPLY
Operating Voltage Range (VS)
Interface Voltage Range (VDD I/O)
Supply Current
Standby Mode Leakage Current
Turn-On (Wake-Up) Time5
TEMPERATURE
Operating Temperature Range
Test Conditions/Comments
Each axis
User selectable
Percentage of full scale
Measured over any 50 mg interval
Each axis
Default resolution
Full resolution enabled
Full resolution enabled
Full resolution enabled
Full resolution enabled
Each axis
Any g-range, full resolution mode
±0.5 g, 10-bit or full resolution
±1 g, 10-bit resolution
±2 g, 10-bit resolution
±4 g, 10-bit resolution
Each axis
T = 25°C, XOUT, YOUT
T = 25°C, ZOUT
−40°C < T < +105°C, XOUT, YOUT, referenced to initial 0 g output
−40°C < T < +105°C, ZOUT, referenced to initial 0 g output
XOUT, YOUT
ZOUT
X-, Y-axes
Z-axis
X-, Y-axes, 100 Hz output data rate (ODR)
Z-axis, 100 Hz ODR
User selectable
Data rate ≥ 100 Hz, 2.0 V ≤ VS ≤ 3.6 V
Data rate > 100 Hz
Data rate < 10 Hz
Min Typ
Max Unit
±0.5, ±1, ±2, ±4
±0.5
±2
±0.1
±1
g
%
%
Degrees
%
10 Bits
10 Bits
11 Bits
12 Bits
13 Bits
1024
921 1024
460 512
230 256
115 128
±0.01
1126
563
282
141
LSB/g
LSB/g
LSB/g
LSB/g
LSB/g
%/°C
−125
−200
±50
±75
±0.5
±0.75
+125
+200
mg
mg
mg
mg
mg/°C
mg/°C
150 µg/√Hz
250 µg/√Hz
1.5 mg rms
2.5 mg rms
6.25 3200 Hz
0.20
−2.36
0.30
2.36
−0.20
3.70
g
g
g
2.0
1.7
100 170
30 55
0.1
1.4
3.6 V
VS V
300 µA
110 µA
2 µA
ms
−40 +105 °C
1 All minimum and maximum specifications are guaranteed. Typical specifications are not guaranteed.
2 Cross-axis sensitivity is defined as coupling between any two axes.
3 Bandwidth is half the output data rate.
4 Self test change is defined as the output (g) when the SELF_TEST bit = 1 (in the DATA_FORMAT register, Address 0x31) minus the output (g) when the SELF_TEST bit =
0 (in the DATA_FORMAT register). Due to device filtering, the output reaches its final value after 4 × τ when enabling or disabling self test, where τ = 1/(data rate).
5 Turn-on and wake-up times are determined by the user-defined bandwidth. At a 100 Hz data rate, the turn-on and wake-up times are each approximately 11.1 ms. For
other data rates, the turn-on and wake-up times are each approximately τ + 1.1 in milliseconds, where τ = 1/(data rate).
Rev. 0 | Page 3 of 28


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ADXL313
ABSOLUTE MAXIMUM RATINGS
Table 2.
Parameter
Acceleration
Any Axis, Unpowered
Any Axis, Powered
VS
VDD I/O
All Other Pins
Output Short-Circuit Duration
(Any Pin to Ground)
Temperature Range
Powered
Storage
Rating
10,000 g
10,000 g
−0.3 V to +3.9 V
−0.3 V to +3.9 V
−0.3 V to VDD I/O + 0.3 V or 3.9 V,
whichever is less
Indefinite
−40°C to +125°C
−40°C to +125°C
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
Data Sheet
THERMAL RESISTANCE
θJA is specified for the worst-case conditions, that is, a device
soldered in a circuit board for surface-mount packages.
Table 3. Thermal Resistance
Package Type
32-Lead LFCSP Package
θJA
27.27
θJC
30
Unit
°C/W
ESD CAUTION
Rev. 0 | Page 4 of 28


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Data Sheet
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
ADXL313
GND 1
RESERVED 2
GND 3
GND 4
VS 5
CS 6
RESERVED 7
NC 8
ADXL313
TOP VIEW
(Not to Scale)
24 SDA/SDI/SDIO
23 SDO/ALT ADDRESS
22 RESERVED
21 INT2
20 INT1
19 NC
18 NC
17 NC
Table 4. Pin Function Descriptions
Pin No.
Mnemonic
1 GND
2 RESERVED
3 GND
4 GND
5 VS
6 CS
7 RESERVED
8 to 19
NC
20 INT1
21 INT2
22 RESERVED
23 SDO/ALT ADDRESS
24 SDA/SDI/SDIO
25 NC
26 SCL/SCLK
27 to 30
NC
31 VDD I/O
32 NC
EP
NOTES
1. NC = NO CONNECT. DO NOT CONNECT TO THIS PIN.
2. THE EXPOSED PAD MUST BE SOLDERED TO THE GROUND PLANE.
Figure 2. Pin Configuration
Description
This pin must be connected to ground.
Reserved. This pin must be connected to VS or left open.
This pin must be connected to ground.
This pin must be connected to ground.
Supply Voltage.
Chip Select.
Reserved. This pin must be left open.
No Connect. Do not connect to this pin.
Interrupt 1 Output.
Interrupt 2 Output.
Reserved. This pin must be connected to GND or left open.
Serial Data Output/Alternate I2C Address Select.
Serial Data (I2C)/Serial Data Input (SPI 4-Wire)/Serial Data Input/Output (SPI 3-Wire).
No Connect. Do not connect to this pin.
I2C Serial Communications Clock/SPI Serial Communications Clock.
No Connect. Do not connect to this pin.
Digital Interface Supply Voltage.
No Connect. Do not connect to this pin.
Exposed Pad. The exposed pad must be soldered to the ground plane.
Rev. 0 | Page 5 of 28


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ADXL313
TYPICAL PERFORMANCE CHARACTERISTICS
125
100
75
50
25
0
–25
–50
–75
–100
–125
–50 –30 –10 10 30 50 70 90 110
TEMPERATURE (°C)
Figure 3. X-Axis Acceleration vs. Temperature, Three Lots (N = 80)
125
100
75
50
25
0
–25
–50
–75
–100
–125
–50 –30 –10 10 30 50 70 90 110
TEMPERATURE (°C)
Figure 4. Y-Axis Acceleration vs. Temperature, Three Lots (N = 80)
200
150
100
50
0
–50
–100
–150
–200
–50 –30 –10 10 30 50 70 90 110
TEMPERATURE (°C)
Figure 5. Z-Axis Acceleration vs. Temperature, Three Lots (N = 80)
Data Sheet
40 1.0
30
20 0.5
10
00
–10
–20 –0.5
–30
–40 –1.0
–2000 –1500 –1000 –500 0 500 1000 1500 2000
INPUT ACCELERATION (mg)
Figure 6. X-Axis Nonlinearity, ±2 g Input Range
40 1.0
30
20 0.5
10
00
–10
–20 –0.5
–30
–40
–2000 –1500 –1000 –500 0 500 1000
INPUT ACCELERATION (mg)
1500
–1.0
2000
Figure 7. Y-Axis Nonlinearity, ±2 g Input Range
40 1.0
30
20 0.5
10
00
–10
–20 –0.5
–30
–40 –1.0
–2000 –1500 –1000 –500 0 500 1000 1500 2000
INPUT ACCELERATION (mg)
Figure 8. Z-Axis Nonlinearity, ±2 g Input Range
Rev. 0 | Page 6 of 28


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Data Sheet
5
4
3
2
1
0
–1
–2
–3
–4
–5
–1000 –750
–500 –250 0 250 500
INPUT ACCELERATION (mg)
750
Figure 9. X-Axis Microlinearity, 50 mg Step Size
1000
5
4
3
2
1
0
–1
–2
–3
–4
–5
–1000 –750
–500 –250 0 250 500
INPUT ACCELERATION (mg)
750
Figure 10. Y-Axis Microlinearity, 50 mg Step Size
1000
5
4
3
2
1
0
–1
–2
–3
–4
–5
–1000 –750
–500 –250 0 250 500
INPUT ACCELERATION (mg)
750 1000
Figure 11. Z-Axis Microlinearity, 50 mg Step Size
ADXL313
80
70
60
50
40
30
20
10
0
CURRENT (nA)
Figure 12. Standby Mode Current Consumption, VS = VDD I/O = 3.3 V, 25°C
35
30
25
20
15
10
5
0
CURRENT CONSUMPTION (µA)
Figure 13. Current Consumption, Measurement Mode, Data Rate = 100 Hz,
VS = VDD I/O = 3.3 V, 25°C
200
150
100
50
0
2.0 2.4 2.8 3.2 3.6
SUPPLY VOLTAGE (V)
Figure 14. Supply Current vs. Supply Voltage, VS at 25°C
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ADXL313
Data Sheet
THEORY OF OPERATION
The ADXL313 is a complete 3-axis acceleration measurement
system with a selectable measurement range of ±0.5 g, ±1 g,
±2 g, or ±4 g. It measures both dynamic acceleration resulting
from motion or shock and static acceleration, such as gravity,
which allows it to be used as a tilt sensor.
The sensor is a polysilicon surface-micromachined structure
built on top of a silicon wafer. Polysilicon springs suspend the
structure over the surface of the wafer and provide a resistance
against acceleration forces.
Deflection of the structure is measured using differential
capacitors that consist of independent fixed plates and plates
attached to the moving mass. Acceleration deflects the beam
and unbalances the differential capacitor, resulting in a sensor
output whose amplitude is proportional to acceleration. Phase-
sensitive demodulation is used to determine the magnitude and
polarity of the acceleration.
POWER SEQUENCING
Power can be applied to VS or VDD I/O in any sequence without
damaging the ADXL313. All possible power-on modes are
summarized in Table 5. The interface voltage level is set with
the interface supply voltage, VDD I/O, which must be present to
ensure that the ADXL313 does not create a conflict on the
communication bus. For single-supply operation, VDD I/O can be
the same as the main supply, VS. In a dual-supply application,
however, VDD I/O can differ from VS to accommodate the desired
interface voltage, as long as VS is greater than or equal to VDDI/O.
After VS is applied, the device enters standby mode, where power
consumption is minimized and the device waits for VDD I/O to be
applied and for the command to enter measurement mode to be
received. (This command can be initiated by setting the measure
bit in the POWER_CTL register (Address 0x2D).) In addition, any
register can be written to or read from to configure the part while
the device is in standby mode. It is recommended that the device
be configured in standby mode before measurement mode is
enabled. Clearing the measure bit returns the device to the standby
mode.
POWER SAVINGS
Power Modes
The ADXL313 automatically modulates its power consumption
in proportion to its output data rate, as outlined in Table 5. If
additional power savings are desired, a lower power mode is
available. In this mode, the internal sampling rate is reduced,
allowing for power savings in the 12.5 Hz to 400 Hz data rate
range at the expense of slightly greater noise. To enter low
power mode, set the LOW_POWER bit (Bit 4) in the BW_RATE
register (Address 0x2C). The current consumption in low power
mode is shown in Table 6 for cases where there is an advantage
to using low power mode. Use of low power mode for a data
rate not shown in Table 6 does not provide any advantage over
the same data rate in normal power mode. Therefore, it is
recommended that only data rates shown in Table 6 be used in
low power mode. The current consumption values shown in
Table 5 and Table 6 are for a VS of 3.3 V.
Table 5. Current Consumption vs. Data Rate
(TA = 25°C, VS = VDD I/O = 3.3 V)
Output Data
Rate (Hz)
Bandwidth (Hz)
Rate Code
3200
1600
1111
1600
800
1110
800 400
1101
400 200
1100
200 100
1011
100 50
1010
50 25
1001
25 12.5
1000
12.5 6.25
0111
6.25 3.125
0110
IDD (µA)
170
115
170
170
170
170
115
82
65
57
Table 6. Current Consumption vs. Data Rate, Low Power Mode
(TA = 25°C, VS = VDD I/O = 3.3 V)
Output Data
Rate (Hz)
Bandwidth (Hz)
Rate Code IDD (µA)
400 200
1100
115
200 100
1011
82
100 50
1010
65
50 25
1001
57
25 12.5
1000
50
12.5 6.25
0111
43
Table 7. Power Sequencing
Condition
VS VDD I/O
Power Off
Off Off
Bus Disabled
On Off
Bus Enabled
Standby or
Measurement
Off On
On On
Description
The device is completely off, but there is a potential for a communication bus conflict.
The device is on in standby mode, but communication is unavailable, and the device creates a conflict
on the communication bus. Minimize the duration of this state during power-up to prevent a conflict.
No functions are available, but the device does not create a conflict on the communication bus.
The device is in standby mode, awaiting a command to enter measurement mode, and all sensor
functions are off. After the device is instructed to enter measurement mode, all sensor functions are
available.
Rev. 0 | Page 8 of 28


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Data Sheet
Autosleep Mode
Additional power savings can be obtained by having the
ADXL313 automatically switch to sleep mode during periods of
inactivity. To enable this feature, set the THRESH_INACT
register (Address 0x25) to an acceleration threshold value.
Levels of acceleration below this threshold are regarded as no
activity. Set TIME_INACT (Address 0x26) to an appropriate
inactivity time period. Then set the AUTO_SLEEP bit and the
link bit in the POWER_CTL register (Address 0x2D). If the
device does not detect a level of acceleration in excess of
THRESH_INACT for TIME_INACT seconds, the device is
transitioned to sleep mode automatically. Current consumption
at less than 10 Hz data rates used in this mode is typically 55 µA
for a VS of 3.3 V.
ADXL313
Standby Mode
For even lower power operation, standby mode can be used.
In standby mode, current consumption is reduced to 0.1 µA
(typical). In this mode, no measurements are made. Standby
mode is entered by clearing the measure bit (Bit 3) in the
POWER_CTL register (Address 0x2D). Placing the device into
standby mode preserves the contents of the FIFO.
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ADXL313
SERIAL COMMUNICATIONS
I2C and SPI digital communications are available. In both cases,
the ADXL313 operates as a slave. I2C mode is enabled if the CS pin
is tied high to VDD I/O. The CS pin must always be tied high to
VDD I/O or be driven by an external controller because there is no
default mode if the CS pin is left unconnected. Therefore, not
taking these precautions may result in an inability to communicate
with the part. In SPI mode, the CS pin is controlled by the bus
master. In both SPI and I2C modes of operation, ignore data
transmitted from the ADXL313 to the master device during
writes to the ADXL313.
SPI
For SPI communication, either 3- or 4-wire configuration is
possible, as shown in the connection diagrams in Figure 15 and
Figure 16. Clearing the SPI bit in the DATA_FORMAT register
(Address 0x31) selects 4-wire mode, whereas setting the SPI bit
selects 3-wire mode. The maximum SPI clock speed is 5 MHz
with 100 pF maximum loading, and the timing scheme follows
clock polarity (CPOL) = 1 and clock phase (CPHA) = 1. If power
is applied to the ADXL313 before the clock polarity and phase
of the host processor are configured, the CS pin must be brought
high before changing the clock polarity and phase. When using
the 3-wire SPI configuration, it is recommended that the SDO
pin be either pulled up to VDD I/O or pulled down to GND via a
10 kΩ resistor.
ADXL313
CS
SDIO
SDO
SCLK
PROCESSOR
D OUT
D IN/OUT
D OUT
Figure 15. 3-Wire SPI Connection Diagram
ADXL313
CS
SDI
SDIO
SCLK
PROCESSOR
D OUT
D OUT
D IN
D OUT
Figure 16. 4-Wire SPI Connection Diagram
Data Sheet
CS is the serial port enable line and is controlled by the SPI master.
This line must go low at the start of a transmission and high at
the end of a transmission, as shown in Figure 17 to Figure 19.
SCLK is the serial port clock and is supplied by the SPI master.
SCLK idles high during a period of no transmission. SDI and
SDO are the serial data input and output, respectively. Data is
updated on the falling edge of SCLK and sampled on the rising
edge of SCLK.
To read or write multiple bytes in a single transmission, the
multiple-byte bit, located after the R/W bit in the first byte transfer
(MB in Figure 17 to Figure 19), must be set. After the register
addressing and the first byte of data, each subsequent set of
clock pulses (eight clock pulses) causes the ADXL313 to point
to the next register for a read or write. This shifting continues
until the clock pulses cease and CS is deasserted. To perform reads
or writes on different, nonsequential registers, CS must be
deasserted between transmissions, and the new register must be
addressed separately.
The timing diagram for 3-wire SPI reads or writes is shown in
Figure 17. The 4-wire equivalents for SPI reads and writes are
shown in Figure 18 and Figure 19, respectively. For correct
operation of the part, the logic thresholds and timing parameters
in Table 8 and Table 9 must be met at all times.
Use of the 3200 Hz and 1600 Hz output data rates is recommended
only with SPI communication rates greater than or equal to 2
MHz. The 800 Hz output data rate is recommended only for
communication speeds greater than or equal to 400 kHz, and
the remaining data rates scale proportionally. For example, the
minimum recommended communication speed for a 200 Hz
output data rate is 100 kHz. Operation at an output data rate
below the recommended minimum may result in undesirable
effects on the acceleration data, including missing samples or
additional noise.
Rev. 0 | Page 10 of 28


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Data Sheet
ADXL313
Table 8. SPI Digital Input/Output
Parameter
Digital Input
Low Level Input Voltage (VIL)
High Level Input Voltage (VIH)
Low Level Input Current (IIL)
High Level Input Current (IIH)
Digital Output
Low Level Output Voltage (VOL)
High Level Output Voltage (VOH)
Low Level Output Current (IOL)
High Level Output Current (IOH)
Pin Capacitance
Test Conditions/Comments
VIN = VDD I/O
VIN = 0 V
IOL = 10 mA
IOH = −4 mA
VOL = VOL, max
VOH = VOH, min
fIN = 1 MHz, VIN = 2.5 V
Limit1
Min Max
0.7 × VDD I/O
−0.1
0.3 × VDD I/O
0.1
0.8 × VDD I/O
10
0.2 × VDD I/O
−4
8
Unit
V
V
µA
µA
V
V
mA
mA
pF
1 Limits based on characterization results; not production tested.
Table 9. SPI Timing (TA = 25°C, VS = VDD I/O = 3.3 V)1
Limit2, 3
Parameter Min
Max Unit Description
fSCLK 5 MHz SPI clock frequency.
tSCLK
200
ns 1/(SPI clock frequency) mark-space ratio for the SCLK input is 40/60 to 60/40.
tDELAY
5
ns CS falling edge to SCLK falling edge.
tQUIET
5
ns SCLK rising edge to CS rising edge.
tDIS 10 ns CS rising edge to SDO disabled.
tCS,DIS
150
ns CS deassertion between SPI communications.
tS 0.3 × tSCLK
ns SCLK low pulse width (space).
tM 0.3 × tSCLK
ns SCLK high pulse width (mark).
tSETUP
5
ns SDI valid before SCLK rising edge.
tHOLD
5
ns SDI valid after SCLK rising edge.
tSDO 40 ns SCLK falling edge to SDO/SDIO output transition.
tR4 20 ns SDO/SDIO output high to output low transition.
tF4 20 ns SDO/SDIO output low to output high transition.
1 The CS, SCLK, SDI, and SDO pins are not internally pulled up or down; they must be driven for proper operation.
2 Limits based on characterization results, characterized with fSCLK = 5 MHz and bus load capacitance of 100 pF; not production tested.
3 The timing values are measured corresponding to the input thresholds (VIL and VIH) given in Table 8.
4 Output rise and fall times measured with capacitive load of 150 pF.
Rev. 0 | Page 11 of 28


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ADXL313
Data Sheet
CS
tDELAY
tSCLK
tM tS
SCLK
SDIO
tSETUP
R/W
tHOLD
MB
A5
tR, tF
A0
tSDO
D7
SDO
NOTES
1. tSDO IS ONLY PRESENT DURING READS.
ADDRESS BITS
DATA BITS
Figure 17. SPI 3-Wire Read/Write
tQUIET
D0
tCS,DIS
CS
SCLK
SDI
SDO
CS
SCLK
SDI
SDO
tDELAY
tSETUP
R
X
tSCLK
tM tS
tHOLD
MB
tSDO
X
A5 A0
ADDRESS BITS
X
X
tR, tF
Figure 18. SPI 4-Wire Read
X
D7
DATA BITS
tDELAY
tSETUP
W
X
tSCLK
tM tS
tHOLD
MB
tSDO
X
A5 A0
ADDRESS BITS
XX
tR, tF
Figure 19. SPI 4-Wire Write
D7
DATA BITS
X
tQUIET
tCS,DIS
X
tDIS
D0
tQUIET
tCS,DIS
D0
tDIS
X
Rev. 0 | Page 12 of 28


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Data Sheet
ADXL313
I2C
With CS tied high to VDD I/O, the ADXL313 is in I2C mode,
requiring a simple 2-wire connection, as shown in Figure 20.
The ADXL313 conforms to the UM10204 I2C-Bus Specification
and User Manual, Rev. 03—19 June 2007, available from NXP
Semiconductor. It supports standard (100 kHz) and fast (400 kHz)
data transfer modes if the bus parameters given in Table 10 and
Table 11 are met. Single- or multiple-byte reads/writes are
supported, as shown in Figure 21. With the ALT ADDRESS pin
high, the 7-bit I2C address for the device is 0x1D, followed by the
R/W bit. This translates to 0x3A for a write and 0x3B for a read. An
alternate I2C address of 0x53 (followed by the R/W bit) can be
chosen by grounding the ALT ADDRESS pin (Pin 23). This
translates to 0xA6 for a write and 0xA7 for a read.
VDD I/O
ADXL313
CS
SDA
ALT ADDRESS
SCL
RP
RP PROCESSOR
D IN/OUT
D OUT
Figure 20. I2C Connection Diagram (Address 0x53)
If other devices are connected to the same I2C bus, the nominal
operating voltage level of these other devices cannot exceed VDDI/O
by more than 0.3 V. External pull-up resistors, RP, are necessary
for proper I2C operation. To ensure proper operation, refer to
the UM10204 I2C-Bus Specification and User Manual, Rev. 03—
19 June 2007, when selecting pull-up resistor values.
Table 10. I2C Digital Input/Output
Parameter
Digital Input
Low Level Input Voltage (VIL)
High Level Input Voltage (VIH)
Low Level Input Current (IIL)
High Level Input Current (IIH)
Digital Output
Low Level Output Voltage (VOL)
Low Level Output Current (IOL)
Pin Capacitance
Test Conditions/Comments
VIN = VDD I/O
VIN = 0 V
VDD I/O < 2 V, IOL = 3 mA
VDD I/O ≥ 2 V, IOL = 3 mA
VOL = VOL, max
fIN = 1 MHz, VIN = 2.5 V
Min
0.7 × VDD I/O
−0.1
3
Limit1
Max
0.3 × VDD I/O
0.1
0.2 × VDD I/O
400
8
Unit
V
V
µA
µA
V
mV
mA
pF
1 Limits based on characterization results; not production tested.
SINGLE-BYTE WRITE
MASTER START SLAVE ADDRESS + WRITE
SLAVE
ACK
REGISTER ADDRESS
ACK
DATA
STOP
ACK
MULTIPLE-BYTE WRITE
MASTER START SLAVE ADDRESS + WRITE
SLAVE
ACK
REGISTER ADDRESS
ACK
DATA
ACK
DATA
SINGLE-BYTE READ
MASTER START SLAVE ADDRESS + WRITE
SLAVE
ACK
REGISTER ADDRESS
START1
ACK
SLAVE ADDRESS + READ
ACK
MULTIPLE-BYTE READ
MASTER START SLAVE ADDRESS + WRITE
SLAVE
ACK
REGISTER ADDRESS
START1
ACK
SLAVE ADDRESS + READ
ACK
NOTES
1. THIS START IS EITHER A RESTART OR A STOP FOLLOWED BY A START.
2. THE SHADED AREAS REPRESENT WHEN THE DEVICE IS LISTENING.
Figure 21. I2C Device Addressing
STOP
ACK
DATA
NACK STOP
DATA
ACK
DATA
NACK STOP
Rev. 0 | Page 13 of 28


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ADXL313
Data Sheet
Table 11. I2C Timing (TA = 25°C, VS = VDD I/O = 3.3 V)
Limit1, 2
Parameter
Min Max Unit
fSCL 400 kHz
t1 2.5
t2 0.6
t3 1.3
t4 0.6
µs
µs
µs
µs
t5 100
ns
t63, 4, 5, 6
0 0.9 µs
t7 0.6
µs
t8 0.6
µs
t9 1.3
µs
t10 300 ns
0 ns
t11 250 ns
300 ns
20 + 0.1 Cb7
ns
Cb 400 pF
Description
SCL clock frequency
SCL cycle time
SCL high time
SCL low time
Start/repeated start condition hold time
Data setup time
Data hold time
Setup time for repeated start
Stop condition setup time
Bus-free time between a stop condition and a start condition
Rise time of both SCL and SDA when receiving
Rise time of both SCL and SDA when receiving or transmitting
Fall time of SDA when receiving
Fall time of both SCL and SDA when transmitting
Fall time of both SCL and SDA when transmitting or receiving
Capacitive load for each bus line
1 Limits based on characterization results, with fSCL = 400 kHz and a 3 mA sink current; not production tested.
2 All values referred to the VIH and the VIL levels given in Table 10.
3 t6 is the data hold time that is measured from the falling edge of SCL. It applies to data in transmission and acknowledge.
4 A transmitting device must internally provide an output hold time of at least 300 ns for the SDA signal (with respect to VIH, min of the SCL signal) to bridge the undefined
region of the falling edge of SCL.
5 The maximum t6 value must be met only if the device does not stretch the low period (t3) of the SCL signal.
6 The maximum value for t6 is a function of the clock low time (t3), the clock rise time (t10), and the minimum data setup time (t5(min)). This value is calculated as
t6(max) = t3 − t10 − t5(min).
7 Cb is the total capacitance of one bus line in picofarads.
SDA
t9 t3 t10
t11
t4
SCL
t4
START
CONDITION
t6 t2 t5
t7
REPEATED
START
CONDITION
Figure 22. I2C Timing Diagram
t1
t8
STOP
CONDITION
Rev. 0 | Page 14 of 28


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Data Sheet
ADXL313
INTERRUPTS
The ADXL313 provides two output pins for driving interrupts:
INT1 and INT2. Both interrupt pins are push-pull, low impedance
pins with output specifications shown in Table 12. The default
configuration of the interrupt pins is active high. This can be
changed to active low by setting the INT_INVERT bit in the
DATA_FORMAT register (Address 0x31). All functions can be
used simultaneously, with the only limiting feature being that
some functions may need to share interrupt pins.
Interrupts are enabled by setting the appropriate bit in the
INT_ENABLE register (Address 0x2E) and are mapped to either
the INT1 or INT2 pin based on the contents of the INT_MAP
register (Address 0x2F). When initially configuring the interrupt
pins, it is recommended that the functions and interrupt mapping
be completed before enabling the interrupts. When changing the
configuration of an interrupt, it is recommended that the interrupt
be disabled first, by clearing the bit corresponding to that function
in the INT_ENABLE register, and then the function be reconfig-
ured before enabling the interrupt again. Configuration of the
functions while the interrupts are disabled helps to prevent the
accidental generation of an interrupt.
The interrupt functions are latched and cleared either by reading
the data registers (Address 0x32 to Address 0x37) until the inter-
rupt condition is no longer valid for the data-related interrupts
or by reading the INT_SOURCE register (Address 0x30) for the
remaining interrupts. The following sections describe the
interrupts that can be set in the INT_ENABLE register and
monitored in the INT_SOURCE register.
DATA_READY
The DATA_READY bit is set when new data is available and is
cleared when no new data is available.
Table 12. Interrupt Pin Digital Output
Parameter
Digital Output
Low Level Output Voltage (VOL)
High Level Output Voltage (VOH)
Low Level Output Current (IOL)
High Level Output Current (IOH)
Pin Capacitance
Rise/Fall Time
Rise Time (tR)2
Fall Time (tF)3
Test Conditions/Comments
IOL = 300 µA
IOH = −150 µA
VOL = VOL, max
VOH = VOH, min
fIN = 1 MHz, VIN = 2.5 V
CLOAD = 150 pF
CLOAD = 150 pF
1 Limits based on characterization results, not production tested.
2 Rise time is measured as the transition time from VOL, max to VOH, min of the INTx pin.
3 Fall time is measured as the transition time from VOH, min to VOL, max of the INTx pin.
Activity
The activity bit is set when acceleration greater than the value
stored in the THRESH_ACT register (Address 0x24) is sensed.
Inactivity
The inactivity bit is set when acceleration of less than the value
stored in the THRESH_INACT register (Address 0x25) is sensed
for more time than is specified in the TIME_INACT register
(Address 0x26). The maximum value for TIME_INACT is 255 sec.
Watermark
The watermark bit is set when the number of samples in
the FIFO equals the value stored in the samples bits in the
FIFO_CTL register (Address 0x38). The watermark bit is
cleared automatically when the FIFO is read, and the content
returns to a value below the value stored in the samples bits.
Overrun
The overrun bit is set when new data replaces unread data. The
precise operation of the overrun function depends on the FIFO
mode. In bypass mode, the overrun bit is set when new data
replaces unread data in the DATA_Xx, DATA_Yx, and DATA_Zx
registers (Address 0x32 to Address 0x37). In all other modes, the
overrun bit is set when the FIFO is filled. The overrun bit is
automatically cleared when the contents of FIFO are read.
FIFO
The ADXL313 contains patent pending technology for an
embedded memory management system with a 32-level FIFO
that can be used to minimize host processor burden. This buffer
has four modes: bypass, FIFO, stream, and trigger (see Table 17).
Each mode is selected by the settings of the FIFO_MODE bits
in the FIFO_CTL register (Address 0x38).
Bypass Mode
In bypass mode, the FIFO is not operational and, therefore,
remains empty.
Min
0.8 × VDD I/O
300
Limit1
Max
0.2 × VDD I/O
−150
8
210
150
Unit
V
V
µA
µA
pF
ns
ns
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ADXL313
FIFO Mode
In FIFO mode, data from measurements of the x-, y-, and z-axes
are stored in the FIFO. When the number of samples in the FIFO
equals the level specified in the samples bits of the FIFO_CTL
register (Address 0x38), the watermark interrupt is set. The
FIFO continues accumulating samples until it is full (32 samples
from measurements of the x-, y-, and z-axes) and then stops
collecting data. After the FIFO stops collecting data, the device
continues to operate; therefore, features such as activity detection
can be used after the FIFO is full. The watermark interrupt contin-
ues to occur until the number of samples in the FIFO is less
than the value stored in the samples bits of the FIFO_CTL
register.
Stream Mode
In stream mode, data from measurements of the x-, y-, and z-
axes is stored in FIFO. When the number of samples in the FIFO
equals the level specified in the samples bits of the FIFO_CTL
register (Address 0x38), the watermark interrupt is set. FIFO
continues accumulating samples and holds the latest 32 samples
from measurements of the x-, y-, and z-axes, discarding older
data as new data arrives. The watermark interrupt continues
occurring until the number of samples in FIFO is less than the
value stored in the samples bits of the FIFO_CTL register.
Trigger Mode
In trigger mode, the FIFO accumulates samples, holding the
latest 32 samples from measurements of the x-, y-, and z-axes.
After a trigger event occurs and an interrupt is sent to the INT1
or INT2 pin (determined by the trigger bit in the FIFO_CTL
register), FIFO keeps the last n samples (where n is the value
specified by the samples bits in the FIFO_CTL register) and
then operates in FIFO mode, collecting new samples only when
the FIFO is not full. A delay of at least 5 μs must be present between
the trigger event occurring and the start of reading data from
the FIFO to allow the FIFO to discard and retain the necessary
samples. Additional trigger events cannot be recognized until
the trigger mode is reset. To reset the trigger mode, set the device
to bypass mode and then set the device back to trigger mode. Note
that the FIFO data must be read first because placing the device
into bypass mode clears FIFO.
Retrieving Data from FIFO
The FIFO data is read through the DATA_Xx, DATA_Yx, and
DATA_Zx registers (Address 0x32 to Address 0x37). When the
FIFO is in FIFO, stream, or trigger mode, reads to the DATA_Xx,
DATA_xY, and DATA_Zx registers read data stored in the
FIFO. Each time data is read from the FIFO, the oldest x-, y-,
and z-axes data is placed into the DATA_Xx, DATA_Yx, and
DATA_Zx registers.
Data Sheet
If a single-byte read operation is performed, the remaining
bytes of data for the current FIFO sample are lost. Therefore, all
axes of interest must be read in a burst (or multiple-byte) read
operation. To ensure that the FIFO has completely popped (that
is, that new data has completely moved into the DATA_Xx,
DATA_Yx, and DATA_Zx registers), there must be at least 5 μs
between the end of reading the data registers and the start of a
new read of the FIFO or a read of the FIFO_STATUS register
(Address 0x39). The end of reading a data register is signified by
the transition from Register 0x37 to Register 0x38 or by the CS pin
going high.
For SPI operation at 1.6 MHz or less, the register addressing
portion of the transmission is a sufficient delay to ensure that
the FIFO has completely popped. For SPI operation greater than
1.6 MHz, it is necessary to deassert the CS pin to ensure a total
delay of 5 μs; otherwise, the delay is not sufficient. The total delay
necessary for 5 MHz operation is at most 3.4 μs. This is not a
concern when using I2C mode because the communication rate is
low enough to ensure a sufficient delay between FIFO reads.
SELF TEST
The ADXL313 incorporates a self test feature that effectively
tests its mechanical and electronic systems simultaneously.
When the self test function is enabled (via the SELF_TEST bit
in the DATA_FORMAT register, Address 0x31), an electrostatic
force is exerted on the mechanical sensor. This electrostatic force
moves the mechanical sensing element in the same manner as
acceleration, and it is additive to the acceleration experienced
by the device. This added electrostatic force results in an output
change in the x-, y-, and z-axes. Because the electrostatic force
is proportional to VS2, the output change varies with VS. The self
test feature of the ADXL313 also exhibits a bimodal behavior.
However, the limits shown in Table 1 and Table 13 are valid for
all potential self test values across the entire allowable voltage
range. Use of the self test feature at data rates of less than 100 Hz or
at 1600 Hz may yield values outside these limits. Therefore, the
part must be in normal power operation (LOW_POWER bit = 0
in the BW_RATE register, Address 0x2C) and be placed into a
data rate of 100 Hz through 800 Hz or 3200 Hz for the self test
function to operate correctly.
Table 13. Self Test Output (TA = 25°C, 2.0 V ≤ VS ≤ 3.6 V)
Axis Min (g)
Max (g)
X 0.20
2.36
Y −2.36
+0.20
Z 0.30
3.70
Rev. 0 | Page 16 of 28


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Data Sheet
ADXL313
REGISTER MAP
Table 14. Register Map
Reg
0x00
0x01
0x02
0x03
0x04
0x05 to
0x17
0x18
0x19 to
0x1D
0x1E
0x1F
0x20
0x21 to
0x23
0x24
0x25
0x26
0x27
Name
DEVID_0
DEVID_1
PARTID
REVID
XID
Reserved
SOFT_RESET
Reserved
OFSX
OFSY
OFSZ
Reserved
THRESH_ACT
THRESH_INACT
TIME_INACT
ACT_INACT_CTL
0x28 to
0x2B
0x2C
0x2D
Reserved
BW_RATE
POWER_CTL
0x2E INT_ENABLE
0x2F INT_MAP
0x30
INT_SOURCE
0x31
DATA_FORMAT
0x32
0x33
0x34
0x35
0x36
0x37
0x38
0x39
DATA_X0
DATA_X1
DATA_Y0
DATA_Y1
DATA_Z0
DATA_Z1
FIFO_CTL
FIFO_STATUS
Type
R
R
R
R
R
RSVD
R/W
RSVD
R/W
R/W
R/W
RSVD
R/W
R/W
R/W
R/W
RSVD
R/W
R/W
R/W
R/W
R
R/W
R
R
R
R
R
R
R/W
R
D7 D6
ACT_
AC/DC
ACT_X
0
0
DATA_
READY
DATA_
READY
DATA_
READY
SELF_
TEST
0
I2C_
DISABLE
0
0
0
SPI
FIFO_MODE[1:0]
FIFO_TRIG 0
D5
ACT_Y
0
Link
0
0
0
INT_
INVERT
Trigger
D4 D3 D2 D1
DEVID_0[7:0]
DEVID_1[7:0]
PARTID[7:0]
REVID[7:0]
XID[7:0]
Reserved
D0
SOFT_RESET[7:0]
Reserved
OFSX[7:0]
OFSY[7:0]
OFSZ[7:0]
Reserved
THRESH_ACT[7:0]
THRESH_INACT[7:0]
TIME_INACT[7:0]
ACT_Z
INACT_
AC/DC
Reserved
INACT_X INACT_Y
INACT_Z
LOW_POWER
AUTO_SLEEP Measure
Rate[3:0]
Sleep
Wake-up[1:0]
Activity
Inactivity 0
Watermark Overrun
Activity
Inactivity 0
Watermark Overrun
Activity
Inactivity 0
Watermark Overrun
0
FULL_RES Justify
Range[1:0]
DATA_X0[7:0]
DATA_X1[7:0]
DATA_Y0[7:0]
DATA_Y1[7:0]
DATA_Z0[7:0]
DATA_Z1[7:0]
Samples[4:0]
Entries
Reset
Value
0xAD
0x1D
0xDC
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x0A
0x00
0x00
0x00
0x02
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
Rev. 0 | Page 17 of 28


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ADXL313
Data Sheet
REGISTER DEFINITIONS
Register 0x00—DEVID_0 (Read Only)
D7 D6 D5 D4 D3 D2 D1 D0
10101101
The DEVID_0 register holds a fixed device ID identifying
Analog Devices, Inc., as the device manufacturer. The default
value of this register is 0xAD.
Register 0x01—DEVID_1 (Read Only)
D7 D6 D5 D4 D3 D2 D1 D0
00011101
The DEVID_1 register holds a fixed device ID that further
enhances traceability of the ADXL313. The default value of this
register is 0x1D.
Register 0x02—PARTID (Read Only)
D7 D6 D5 D4 D3 D2 D1 D0
11001011
The PARTID register identifies the device as an ADXL313. The
default hexadecimal value stored in this register, 0xDC, is meant
to be interpreted as an octal value that corresponds to 313. If
the user does not read back 0xDC from this register, assume
that the device under test is not an ADXL313 device.
Register 0x03—REVID (Read Only)
D7 D6 D5 D4 D3 D2 D1 D0
REVID[7:0]
The number contained in the REVID register represents the
silicon revision of the ADXL313. This number is incremented
for any major silicon revision.
Register 0x04—XID (Read Only)
D7 D6 D5 D4 D3 D2 D1 D0
XID[7:0]
The XID register stores a semi-unique serial number that is
generated from the device trim and calibration process.
Register 0x18—SOFT_RESET (Read/Write)
D7 D6 D5 D4 D3 D2 D1
SOFT_RESET[7:0]
D0
Writing a value of 0x52 to Register 0x18 triggers the soft reset
function of the ADXL313. The soft reset returns the ADXL313
to the beginning of its power-on initialization routine, clearing
the configuration settings that were written to the memory
map, which allows easy reconfiguration of the ADXL313 device.
Register 0x1E—OFSX (Read/Write),
Register 0x1F—OFSY (Read/Write),
Register 0x20—OFSZ (Read/Write)
D7 D6 D5 D4 D3 D2 D1 D0
OFSX[7:0]
OFSY[7:0]
OFSZ[7:0]
The OFSX, OFSY, and OFSZ registers are each eight bits and
offer user-set offset adjustments in twos complement format
with a scale factor of 3.9 mg/LSB (that is, 0x7F = 0.5 g). The
value stored in the offset registers is automatically added to the
acceleration data, and the resulting value is stored in the output
data registers.
Register 0x24—THRESH_ACT (Read/Write)
D7 D6 D5 D4 D3 D2 D1
D0
THRESH_ACT[7:0]
The THRESH_ACT register is eight bits and holds the threshold
value for detecting activity. The data format is unsigned;
therefore, the magnitude of the activity event is compared with
the value in the THRESH_ACT register. The scale factor is
15.625 mg/LSB. A value of 0 may result in undesirable behavior
if the activity interrupt is enabled.
Register 0x25—THRESH_INACT (Read/Write)
D7 D6 D5 D4 D3 D2 D1
THRESH_INACT[7:0]
D0
The THRESH_INACT register is eight bits and holds the threshold
value for detecting inactivity. The data format is unsigned;
therefore, the magnitude of the inactivity event is compared
with the value in the THRESH_INACT register. The scale factor is
15.625 mg/LSB. A value of 0 may result in undesirable behavior
if the inactivity interrupt is enabled.
Register 0x26—TIME_INACT (Read/Write)
D7 D6 D5 D4 D3 D2
TIME_INACT[7:0]
D1
D0
The TIME_INACT register is eight bits and contains an unsigned
time value. Acceleration must be less than the value in the
THRESH_INACT register for the amount of time represented by
TIME_INACT for inactivity to be declared. The scale factor is
1 sec/LSB. Unlike the other interrupt functions, which use
unfiltered data (see the Threshold section), the inactivity
function uses filtered output data. At least one output sample
must be generated for the inactivity interrupt to be triggered.
This results in the function appearing unresponsive if the
TIME_INACT register is set to a value less than the time
constant of the output data rate. A value of 0 results in an
interrupt when the output data is less than the value in the
THRESH_INACT register.
Register 0x27—ACT_INACT_CTL (Read/Write)
D7 D6 D5 D4
ACT_AC/DC ACT_X
ACT_Y
ACT_Z
D3 D2 D1 D0
INACT_AC/DC INACT_X
INACT_Y
INACT_Z
ACT_AC/DC and INACT_AC/DC Bits
A setting of 0 selects dc-coupled operation, and a setting of 1
enables ac-coupled operation. In dc-coupled operation, the
current acceleration magnitude is compared directly with
THRESH_ACT and THRESH_INACT to determine whether
activity or inactivity is detected.
Rev. 0 | Page 18 of 28


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Data Sheet
ADXL313
In ac-coupled operation for activity detection, the acceleration
value at the start of activity detection is taken as a reference
value. New samples of acceleration are then compared to this
reference value and, if the magnitude of the difference exceeds
the THRESH_ACT value, the device triggers an activity interrupt.
Similarly, in ac-coupled operation for inactivity detection, a
reference value is used for comparison and is updated whenever
the device exceeds the inactivity threshold. After the reference
value is selected, the device compares the magnitude of the
difference between the reference value and the current acceleration
with THRESH_INACT. If the difference is less than the value in
THRESH_INACT for the time in TIME_INACT, the device is
considered inactive and the inactivity interrupt is triggered.
ACT_x and INACT_x Bits
A setting of 1 enables x-, y-, or z-axis participation in detecting
activity or inactivity. A setting of 0 excludes the selected axis
from participation. If all axes are excluded, the function is
disabled. For activity detection, all participating axes are
logically OR’ed, causing the activity function to trigger when
any of the participating axes exceeds the threshold. For inactiv-
ity detection, all participating axes are logically AND’ed, causing
the inactivity function to trigger only if all participating axes are
below the threshold for the specified period of time.
Register 0x2C—BW_RATE (Read/Write)
D7 D6 D5 D4
D3 D2 D1
0 0 0 LOW_POWER
Rate
D0
LOW_POWER Bit
A setting of 0 in the LOW_POWER bit selects normal operation,
and a setting of 1 selects reduced power operation, which has
somewhat higher noise (see the Power Modes section for details).
Rate Bits
These bits select the device bandwidth and output data rate (see
Table 5 and Table 6 for details). The default value is 0x0A, which
translates to a 100 Hz output data rate. Select an output data
rate that is appropriate for the communication protocol and
frequency selected. Selecting too high of an output data rate
with a low communication speed results in samples being
discarded.
Register 0x2D—POWER_CTL (Read/Write)
D7 D6 D5 D4
0
I2C_DISABLE Link
AUTO_SLEEP
D3 D2 D1 D0
Measure
Sleep
Wake-up
I2C_Disable Bit
The ADXL313 is capable of communicating via SPI or I2C
transmission protocols. Typically, these protocols do not
overlap; however, situations may arise where SPI transactions
can imitate an I2C start command. This causes the ADXL313 to
respond unexpectedly, causing a communications issue with
other devices on the network. To ensure that the ADXL313 does
not interpret SPI commands as an I2C start condition, assert the
I2C_Disable bit.
Link Bit
A setting of 1 in the link bit with both the activity and inactivity
functions enabled delays the start of the activity function until
inactivity is detected. After activity is detected, inactivity detection
begins, preventing the detection of activity. This bit serially links
the activity and inactivity functions. When this bit is set to 0,
the inactivity and activity functions are concurrent. Additional
information can be found in the Link Mode section.
When clearing the link bit, it is recommended that the part be
placed into standby mode and then set back to measurement
mode with a subsequent write. This is done to ensure that the
device is properly biased if sleep mode is manually disabled;
otherwise, the first few samples of data after the link bit is cleared
may have additional noise, especially if the device was asleep
when the bit was cleared.
AUTO_SLEEP Bit
If the link bit is set, a setting of 1 in the AUTO_SLEEP bit sets
the ADXL313 to switch to sleep mode when inactivity is detected
(that is, when acceleration is below the THRESH_INACT value for
at least the time indicated by TIME_INACT). A setting of 0
disables automatic switching to sleep mode. See the description of
the sleep bit in the Sleep Bit section for more information.
When clearing the AUTO_SLEEP bit, it is recommended that the
part be placed into standby mode and then set back to measure-
ment mode with a subsequent write. This is done to ensure that
the device is properly biased if sleep mode is manually disabled;
otherwise, the first few samples of data after the AUTO_SLEEP
bit is cleared may have additional noise, especially if the device
was asleep when the bit was cleared.
Measure Bit
A setting of 0 in the measure bit places the part into standby mode,
and a setting of 1 places the part into measurement mode. The
ADXL313 powers up in standby mode with minimum power
consumption.
Sleep Bit
A setting of 0 in the sleep bit puts the part into the normal mode
of operation, and a setting of 1 places the part into sleep mode.
Sleep mode suppresses DATA_READY (see Register 0x2E,
Register 0x2F, and Register 0x30), stops transmission of data to the
FIFO, and switches the sampling rate to one specified by the
wake-up bits. In sleep mode, only the activity function can be used.
When clearing the sleep bit, it is recommended that the part be
placed into standby mode and then set back to measurement
mode with a subsequent write. This is done to ensure that the
device is properly biased if sleep mode is manually disabled;
otherwise, the first few samples of data after the sleep bit is
cleared may have additional noise, especially if the device was
asleep when the bit was cleared.
Rev. 0 | Page 19 of 28


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ADXL313
Wake-Up Bits
These bits control the frequency of readings in sleep mode as
described in Table 15.
Table 15. Frequency of Readings in Sleep Mode
Setting
D1 D0 Frequency (Hz)
008
014
102
111
Register 0x2E—INT_ENABLE (Read/Write)
D7 D6 D5
DATA_READY 0
0
D3 D2 D1
Inactivity
0
Watermark
D4
Activity
D0
Overrun
Setting bits in this register to a value of 1 enables their respective
functions to generate interrupts, whereas a value of 0 prevents
the functions from generating interrupts. The DATA_READY,
watermark, and overrun bits enable only the interrupt output;
the functions are always enabled. It is recommended that interrupts
be configured before enabling their outputs.
Register 0x2F—INT_MAP (Read/Write)
D7 D6 D5
DATA_READY 0
0
D3 D2 D1
Inactivity
0
Watermark
D4
Activity
D0
Overrun
Any bits set to 0 in this register send their respective interrupts to
the INT1 pin, whereas bits set to 1 send their respective interrupts
to the INT2 pin. All selected interrupts for a given pin are OR’ed.
Register 0x30—INT_SOURCE (Read Only)
D7 D6 D5
DATA_READY 0
0
D3 D2 D1
Inactivity
0
Watermark
D4
Activity
D0
Overrun
Bits set to 1 in this register indicate that their respective functions
have triggered an event, whereas a value of 0 indicates that the
corresponding event has not occurred. The DATA_READY,
watermark, and overrun bits are always set if the corresponding
events occur, regardless of the INT_ENABLE register settings,
and are cleared by reading data from the DATA_Xx, DATA_Yx,
and DATA_Zx registers. The DATA_READY and watermark
bits may require multiple reads, as indicated in the FIFO mode
descriptions in the FIFO section. Other bits, and the corresponding
interrupts, are cleared by reading the INT_SOURCE register.
Data Sheet
Register 0x31—DATA_FORMAT (Read/Write)
D7 D6 D5
D4 D3
D2
SELF_TEST SPI INT_INVERT 0 FULL_RES Justify
D1 D0
Range
The DATA_FORMAT register controls the presentation of data
to Register 0x32 through Register 0x37. All data, except that for
the ±4 g range, must be clipped to avoid rollover.
SELF_TEST Bit
A setting of 1 in the SELF_TEST bit applies a self test force to
the sensor, causing a shift in the output data. A value of 0 disables
the self test force.
SPI Bit
A value of 1 in the SPI bit sets the device to 3-wire SPI mode,
and a value of 0 sets the device to 4-wire SPI mode.
INT_INVERT Bit
A value of 0 in the INT_INVERT bit sets the interrupts to active
high, and a value of 1 sets the interrupts to active low.
FULL_RES Bit
When this bit is set to a value of 1, the device is in full resolution
mode, where the output resolution increases with the g range
set by the range bits to maintain 1024 LSB/g sensitivity. When
the FULL_RES bit is set to 0, the device is in 10-bit mode, and
the range bits determine the maximum g range and scale factor.
Justify Bit
A setting of 1 in the justify bit selects left (MSB) justified mode,
and a setting of 0 selects right justified (LSB) mode with sign
extension.
Range Bits
These bits set the g range as described in Table 16.
Table 16. g Range Setting
Setting
D1 D0
Range (g)
00
±0.5
01
±1
10
±2
11
±4
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Data Sheet
Register 0x32 and Register 0x33—DATA_X0, DATA_X1
(Read Only),
Register 0x34 and Register 0x35—DATA_Y0, DATA_Y1
(Read Only),
Register 0x36 and Register 0x37—DATA_Z0, DATA_Z1
(Read Only)
D7 D6 D5 D4 D3 D2 D1 D0
DATA_X0[7:0]
DATA_X1[7:0]
DATA_Y0[7:0]
DATA_Y1[7:0]
DATA_Z0[7:0]
DATA_Z1[7:0]
These six bytes (Register 0x32 to Register 0x37) are eight bits
each and hold the output data for each axis. Register 0x32 and
Register 0x33 hold the output data for the x-axis, Register 0x34 and
Register 0x35 hold the output data for the y-axis, and Register 0x36
and Register 0x37 hold the output data for the z-axis.
The output data is twos complement, with DATA_x0 as the least
significant byte and DATA_x1 as the most significant byte, where x
represent X, Y, or Z. The DATA_FORMAT register (Address 0x31)
controls the format of the data. It is recommended that a multiple-
byte read of all registers be performed to prevent a change in
data between reads of sequential registers.
Register 0x38—FIFO_CTL (Read/Write)
D7 D6 D5
D4 D3 D2 D1
FIFO_MODE
Trigger
Samples
D0
FIFO_MODE Bits
These bits set the FIFO mode, as described in Table 17.
Table 17. FIFO Modes
Setting
D7 D6 Mode Function
0 0 Bypass FIFO is bypassed.
0 1 FIFO
FIFO collects up to 32 values and then
stops collecting data, collecting new data
only when FIFO is not full.
1 0 Stream FIFO holds the last 32 data values. When
FIFO is full, the oldest data is overwritten
with newer data.
1 1 Trigger When triggered by the trigger bit, FIFO
holds the last data samples before the
trigger event and then continues to collect
data until full. New data is collected only
when FIFO is not full.
ADXL313
Trigger Bit
A value of 0 in the trigger bit links the trigger event to INT1,
and a value of 1 links the trigger event to INT2.
Samples Bits
The function of these bits depends on the FIFO mode selected
(see Table 18). Entering a value of 0 in the samples bits immedi-
ately sets the watermark status bit in the INT_SOURCE register,
regardless of which FIFO mode is selected. Undesirable opera-
tion may occur if a value of 0 is used for the samples bits when
trigger mode is used.
Table 18. Samples Bits Functions
FIFO Mode Samples Bits Function
Bypass
None.
FIFO Specifies how many FIFO entries are needed to
trigger a watermark interrupt.
Stream
Specifies how many FIFO entries are needed to
trigger a watermark interrupt.
Trigger
Specifies how many FIFO samples are retained in
the FIFO buffer before a trigger event.
0x39—FIFO_STATUS (Read Only)
D7 D6 D5 D4 D3 D2 D1 D0
FIFO_TRIG
0
Entries
FIFO_TRIG Bit
A 1 in the FIFO_TRIG bit corresponds to a trigger event occurring,
and a 0 means that a FIFO trigger event has not occurred.
Entries Bits
These bits report how many data values are stored in the FIFO.
Access to collect the data from the FIFO is provided through
the DATA_Xx, DATA_Yx, and DATA_Zx registers. FIFO reads
must be done in burst or multiple-byte mode because each FIFO
level is cleared after any read (single- or multiple-byte) of the
FIFO. The FIFO stores a maximum of 32 entries, which equates
to a maximum of 33 entries available at any given time because
an additional entry is available at the output filter of the device.
Rev. 0 | Page 21 of 28


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ADXL313
APPLICATIONS INFORMATION
POWER SUPPLY DECOUPLING
A 1 μF tantalum capacitor (CS) at VS and a 0.1 μF ceramic capacitor
(CI/O) at VDD I/O placed close to the ADXL313 supply pins is
recommended to adequately decouple the accelerometer from
noise on the power supply. If additional decoupling is necessary,
a resistor or ferrite bead, no larger than 100 Ω, in series with VS
may be helpful. Additionally, increasing the bypass capacitance
on VS to a 10 μF tantalum capacitor in parallel with a 0.1 μF
ceramic capacitor may also improve noise.
Take care to ensure that the connection from the ADXL313
ground to the power supply ground has low impedance because
noise transmitted through ground has an effect similar to noise
transmitted through VS. It is recommended that VS and VDD I/O
be separate supplies to minimize digital clocking noise on the
VS supply. If this is not possible, additional filtering of the
supplies as previously mentioned may be necessary.
VS VDD I/O
CS CI/O
INTERRUPT
CONTROL
VS VDD I/O
ADXL313
SDA/SDI/SDIO
INT1 SDO/ALT ADDRESS
INT2
SCL/SCLK
GND
CS
3-WIRE OR
4-WIRE SPI
OR I2C
INTERFACE
Figure 23. Application Diagram
MECHANICAL CONSIDERATIONS FOR MOUNTING
Mount the ADXL313 on the PCB in a location close to a hard
mounting point of the PCB to the case. Mounting the ADXL313
at an unsupported PCB location, as shown in Figure 24, may
result in large, apparent measurement errors due to undamped
PCB vibration. Placing the accelerometer near a hard mounting
point ensures that any PCB vibration at the accelerometer is above
the accelerometer’s mechanical sensor resonant frequency and,
therefore, effectively invisible to the accelerometer. Multiple
mounting points close to the sensor and/or a thicker PCB also
help to reduce the effect of system resonance on the performance
of the sensor.
ACCELEROMETERS
PCB
MOUNTING POINTS
Figure 24. Incorrectly Placed Accelerometers
Data Sheet
THRESHOLD
The lower output data rates are achieved by decimating a
common sampling frequency inside the device. The activity
detection function is performed using undecimated data.
Because the bandwidth of the output data varies with the data
rate and is lower than the bandwidth of the undecimated data,
the high frequency and high g data that are used to determine
activity may not be present if the output of the accelerometer is
examined. This may result in functions triggering when accelera-
tion data does not appear to meet the conditions set by the user
for the corresponding function.
LINK MODE
The function of the link bit in the POWER_CTL register
(Address 0x2D) is to reduce the number of activity interrupts
that the processor must service by setting the device to look
for activity only after inactivity. For proper operation of this
feature, the processor must still respond to the activity and
inactivity interrupts by reading the INT_SOURCE register
(Address 0x30) and, therefore, clearing the interrupts. If an activity
interrupt is not cleared, the part cannot go into autosleep mode.
SLEEP MODE vs. LOW POWER MODE
In applications where a low data rate and low power consumption
are desired (at the expense of noise performance), it is recom-
mended that low power mode be used. The use of low power
mode preserves the functionality of the DATA_READY
interrupt and the FIFO for postprocessing of the acceleration
data. Sleep mode, while offering a low data rate and low power
consumption, is not intended for data acquisition.
However, when sleep mode is used in conjunction with the
autosleep mode and the link mode, the part can automatically
switch to a low power, low sampling rate mode when inactivity
is detected. To prevent the generation of redundant inactivity
interrupts, the inactivity interrupt is automatically disabled and
activity is enabled. When the ADXL313 is in sleep mode, the host
processor can also be placed into sleep mode or low power
mode to save significant system power. When activity is
detected, the accelerometer automatically switches back to the
original data rate of the application and provides an activity
interrupt that can be used to wake up the host processor.
Similar to when inactivity occurs, detection of activity events is
disabled and inactivity is enabled.
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Data Sheet
USING SELF TEST
The self test change is defined as the difference between the
acceleration output of an axis with self test enabled and the
acceleration output of the same axis with self test disabled (see
Endnote 4 of Table 1). This definition assumes that the sensor
does not move between these two measurements because, if the
sensor moves, a nonself test related shift corrupts the test.
Proper configuration of the ADXL313 is also necessary for an
accurate self test measurement. Set the part with a data rate
greater than or equal to 100 Hz. This is done by ensuring that a
value greater than or equal to 0x0A is written into the rate bits
(Bit D3 through Bit D0) in the BW_RATE register (Address 0x2C).
The part must also be placed into normal power operation by
ensuring that the LOW_POWER bit in the BW_RATE register
is cleared (LOW_POWER bit = 0) for accurate self test measure-
ments. It is recommended that the part be set to full resolution,
±4 g mode to ensure that there is sufficient dynamic range for
the entire self test shift. This is done by setting Bit D3 of the
DATA_FORMAT register (Address 0x31) and writing a value of
0x03 to the range bits (Bit D1 and Bit D0) of the DATA_FORMAT
register. This results in a high dynamic range for measurement
and 1024 LSB/g sensitivity.
After the part is configured for accurate self test measurement,
several samples of x-, y-, and z-axis acceleration data should be
retrieved from the sensor and averaged together. The number of
samples averaged is a choice of the system designer, but a recom-
mended starting point is 0.1 sec worth of data, which corresponds
to 10 samples at 100 Hz data rate. Store and label the averaged
values appropriately as the self test disabled data, that is, XST_OFF,
YST_OFF, and ZST_OFF.
ADXL313
Next, enable self test by setting Bit D7 of the DATA_FORMAT
register (Address 0x31). The output needs some time (about
four samples) to settle after enabling self test. After allowing the
output to settle, take several samples of the x-, y-, and z-axis
acceleration data, and average them. It is recommended that the
same number of samples be taken for this average as was previously
taken. Store and label these averaged values appropriately as the
value with self test enabled, that is, XST_ON, YST_ON, and ZST_ON.
Self test can then be disabled by clearing Bit D7 of the DATA_
FORMAT register (Address 0x31).
With the stored values for self test enabled and disabled, the self
test change is as follows:
XST = XST_ON XST_OFF
YST = YST_ON YST_OFF
ZST = ZST_ON ZST_OFF
Because the measured output for each axis is expressed in LSBs,
XST, YST, and ZST are also expressed in LSBs. These values can be
converted to acceleration (g) by multiplying each value by the
sensitivity, 1024 LSB/g, when configured for full resolution
mode. When operating in 10-bit mode, the self test delta in
LSBs varies according to the selected g range, even though the
self test force, in g, remains unchanged. Using a range below
±4 g may result in insufficient dynamic range and should be
considered when selecting the range of operation for measuring
self test.
If the self test change is within the valid range, the test is considered
successful. Generally, a part is considered to pass if the minimum
magnitude of change is achieved. However, a part that changes
by more than the maximum magnitude is not necessarily a failure.
Rev. 0 | Page 23 of 28


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ADXL313
3200 HZ AND 1600 HZ ODR DATA FORMATTING
The following section applies for 3200 Hz and 1600 Hz output
data rates only. This section can be ignored for all other data rates.
For 3200 Hz and 1600 Hz output data rates, when the ADXL313
is configured for either a ±0.5 g output range or the full resolution
mode is enabled, the LSB of the output data-word is always 0.
If the acceleration data-word is right justified, this corresponds
to Bit D0 of the DATA_x0 register, as shown in Figure 25 and
Table 19.
When data is left justified and the part is operating in ±0.5 g
mode, the LSB of the output data-word is Bit D6 of the DATAx0
register. In full resolution operation, the location of the LSB
changes according to the selected output range. Table 19 and
Figure 26 demonstrate how the position of the LSB changes
when full resolution mode is enabled.
Data Sheet
Table 19. Conditions for Which the LSB Is Set to 0 (3200 Hz
and 1600 Hz Output Data Rates Only)
Justify
(0x31[2])
FULL_RES
(0x31[3])
Range
(g)
LSB Bit Position
0
0 or 1
±0.5 D0
01
±1 D0
01
±2 D0
01
±4 D0
1
0 or 1
±0.5 D6
11
±1 D5
11
±2 D4
11
±4 D3
The use of 3200 Hz and 1600 Hz output data rates for fixed 10-bit
operation in the ±1 g, ±2 g, and ±4 g output ranges provides an
LSB that is valid and that changes according to the applied accel-
eration. Therefore, in these modes of operation, Bit D0 is not
always 0 when output data is right justified, and Bit D6 is not
always 0 when output data is left justified.
DATA_x1 REGISTER
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
DATA_x0 REGISTER
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 0
FOR THE RIGHT JUSTIFIED DATA:
WHEN OPERATING THE ADXL313 WITH AN OUTPUT RATE OF EITHER 3200Hz OR 1600Hz, THE D0 BIT OF
THE DATA_x0 REGISTER IS ALWAYS 0 UNDER EITHER OF THE FOLLOWING CONDITIONS:
1) FULL RESOLUTION MODE IS ENABLED (ANY g RANGE), OR
2) DEVICE RANGE IS SET TO ±0.5g
Figure 25. Right Justified Data Formatting: 3200 Hz and 1600 Hz Output Data Rate
DATA_x1 REGISTER
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
DATA_x0 REGISTER
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
FULL RESOLUTION AND 10-BIT MODE: LSB FOR ±0.5 RANGE = 0
FULL RESOLUTION MODE; LSB FOR ±1g RANGE = 0
FULL RESOLUTION MODE; LSB FOR ±2g RANGE = 0
FULL RESOLUTION MODE; LSB FOR ±4g RANGE = 0
FOR THE LEFT JUSTIFIED DATA:
WHEN OPERATING THE ADXL313 WITH AN OUTPUT RATE OF EITHER 3200Hz OR 1600Hz, THE LSB OF THE
ACCELERATION DATA-WORD IS ALWAYS 0 UNDER THE FOLLOWING CONDITIONS:
1) FULL RESOLUTION MODE IS ENABLED (ANY g RANGE), OR
2) DEVICE RANGE IS SET TO ±0.5g.
FULL RESOLUTION MODE CAUSES THE LOCATION OF THE LSB TO CHANGE ACCORDING TO
THE SELECTED g RANGE. ALTHOUGH ITS LOCATION MAY CHANGE, ITS VALUE WILL REMAIN 0.
Figure 26. Left Justified Data Formatting: 3200 Hz and 1600 Hz Output Data Rate
Rev. 0 | Page 24 of 28


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Data Sheet
AXES OF ACCELERATION SENSITIVITY
AZ
AY
ADXL313
AX
Figure 27. Axes of Acceleration Sensitivity (Corresponding Output Increases When Accelerated Along the Sensitive Axis)
XOUT = +1g
YOUT = 0g
ZOUT = 0g
XOUT = 0g
YOUT = –1g
ZOUT = 0g
TOP
XOUT = 0g
YOUT = +1g
ZOUT = 0g
GRAVITY
XOUT = –1g
YOUT = 0g
ZOUT = 0g
XOUT = 0g
YOUT = 0g
ZOUT = +1g
Figure 28. Output Response vs. Orientation to Gravity
XOUT = 0g
YOUT = 0g
ZOUT = –1g
Rev. 0 | Page 25 of 28


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ADXL313
SOLDER PROFILE
SUPPLIER TP TC
SUPPLIER tP
TC
TC – 5°C
USER TP TC
USER tP
Data Sheet
TP
TL
TSMAX
TSMAX
MAXIMUM RAMP-UP RATE = 3°C/sec
MAXIMUM RAMP-DOWN RATE = 6°C/sec
PREHEAT AREA
tS
tP
tL
TC – 5°C
25
Table 20. Recommended Soldering Profile1, 2
TIME 25°C TO PEAK
TIME
Figure 29. Recommended Soldering Profile
Profile Feature
Average Ramp Rate (TL to TP)
Preheat
Minimum Temperature (TSMIN)
Maximum Temperature (TSMAX)
Time (TSMIN to TSMAX) (tS)
TSMAX to TL
Ramp-Up Rate
Time Maintained Above Liquidous (tL)
Liquidous Temperature (TL)
Time (tL)
Peak Temperature (TP)
Time Within 5°C of Actual Peak Temperature (tP)
Ramp-Down Rate
Time 25°C to Peak Temperature
Sn63/Pb37
3°C/sec maximum
100°C
150°C
60 sec to 120 sec
3°C/sec
183°C
60 sec to 150 sec
240°C + 0°C/−5°C
10 sec to 30 sec
6°C/sec maximum
6 min maximum
Condition
Pb-Free
3°C/sec maximum
150°C
200°C
60 sec to 180 sec
3°C/sec
217°C
60 sec to 150 sec
260°C + 0°C/−5°C
20 sec to 40 sec
6°C/sec maximum
8 min maximum
1 Based on JEDEC standard J-STD-020D.1.
2 For best results, make sure that the soldering profile is in accordance with the recommendations of the manufacturer of the solder paste used.
Rev. 0 | Page 26 of 28


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Data Sheet
OUTLINE DIMENSIONS
PIN 1
INDICATOR
1.55
1.45
1.35
SEATING
PLANE
5.10
5.00 SQ
4.90
TOP VIEW
0.50
BSC
0.30
0.25
0.18
25
24
32
1
EXPOSED
PAD
PIN 1
INDICATOR
3.70
3.60 SQ
3.50
17 8
0.45
0.40
16 9
BOTTOM VIEW
0.20 MIN
0.35
0.05 MAX
0.02 NOM
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
SECTION OF THIS DATA SHEET.
COPLANARITY
0.05
0.20 REF
COMPLIANT TO JEDEC STANDARDS MO-254-LJJD.
Figure 30. 32-Lead Lead Frame Chip Scale Package [LFCSP_LQ]
5 mm × 5 mm Body, Thick Quad
(CP-32-17)
Dimensions shown in millimeters
0.57mm
5.34mm
0.30mm
3.60mm
ADXL313
0.30mm
0.50mm
0.30mm
Figure 31. Sample Solder Pad Layout (Land Pattern)
Rev. 0 | Page 27 of 28


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ADXL313
Data Sheet
ORDERING GUIDE
Model1, 2
Measurement
Range
ADXL313WACPZ-RL ±0.5 g/±1 g/±2 g/±4 g
Specified
Voltage (V)
3.3
ADXL313WACPZ-RL7 ±0.5 g/±1 g/±2 g/±4 g 3.3
EVAL-ADXL313-Z
EVAL-ADXL313-Z-S
EVAL-ADXL313-Z-M
1 Z = RoHS Compliant Part.
2 W = Qualified for Automotive Applications.
Temperature
Range
−40°C to +105°C
−40°C to +105°C
Package Description
32-Lead Lead Frame Chip Scale Package
[LFCSP_LQ]
32-Lead Lead Frame Chip Scale Package
[LFCSP_LQ]
Evaluation Board
Evaluation Board
Evaluation Board
Package
Option
CP-32-17
CP-32-17
AUTOMOTIVE PRODUCTS
The ADXL313W models are available with controlled manufacturing to support the quality and reliability requirements of automotive
applications. Note that these automotive models may have specifications that differ from the commercial models; therefore, designers
should review the Specifications section of this data sheet carefully. Only the automotive grade products shown are available for use in
automotive applications. Contact your local Analog Devices account representative for specific product ordering information and to
obtain the specific Automotive Reliability reports for these models.
I2C refers to a communications protocol originally developed by Philips Semiconductors (now NXP Semiconductors).
©2013 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D11469-0-4/13(0)
Rev. 0 | Page 28 of 28




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