Analog Devices ADXL313 Datasheet

3-Axis, ±0.5 g/±1 g/±2 g/±4 g

VSV

Data Sheet

FEATURES

Ultralow power (scales automatically with data rate)

As low as 30 µA in measurement mode (V
As low as 0.1 µA in standby mode (V

Low noise performance

150 g/√Hz typical for X- and Y-axes
250 g/√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 I

2

C 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)
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

Car alarms
Hill start aid (HSA) systems
Electronic parking brakes
Data recorders (black boxes)

S

= 3.3 V)

S

= 3.3 V)

FUNCTIONAL BLOCK DIAGRAM

Digital Accelerometer

ADXL313

GENERAL DESCRIPTION

The ADXL313 is a small, thin, low power, 3-axis accelerometer
with high resolution (13-bit) measurement up to ±4 g. Digital
output data is formatted as 16-bit twos complement and is
accessible through either a serial port interface (SPI) (3-wire or
4-wire) or I

The ADXL313 is well suited for car alarm or black box
applications. It measures the static acceleration of gravity in tilt­sensing applications, 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.

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
the ADXL312 accelerometer device.

2

C digital interface.

DD I/O

ADXL313

SENSE

3-AXIS

SENSOR

Rev. C Document Feedback

Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.

ELECTRONICS

GND

ADC

DIGITAL

FILTER

32-LEVEL

FIFO

Figure 1.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] ©2013–2019 Analog Devices, Inc. All rights reserved.

Technical Support www.analog.com

POWER

MANAGEMENT

CONTROL

AND

INTERRUPT

LOGIC

SERIAL I/O

CS

INT1

INT2

SDA/SDI/SDIO

SDO/ALT
ADDRESS

SCL/SCLK

11469-001

ADXL313 Data Sheet

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

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

REVISION HISTORY

2/2019—Rev. B to Rev. C

Changes to Standby Mode Leakage Current Parameter,

Table 1 ................................................................................................ 3

Updated Outline Dimensions ....................................................... 27

Changes to Ordering Guide .......................................................... 28

11/2015—Rev. A to Rev. B

Change to Register 0x02, Table 14 ................................................ 17

Changes to Register 0x02—PARTID (Read Only) Section ....... 18

Change to Preheat Time (T

Table 20 ............................................................................................ 26

11/2013—Rev. 0 to Rev. A

Changes to Figure 3, Figure 4, and Figure 5.................................. 6

4/2013—Revision 0: Initial Version

SMIN

to T

) (tS) Parameter,

SMAX

Rev. C | Page 2 of 28

Data Sheet ADXL313

Micro-Nonlinearity

Measured over any 50 mg interval

±2 %

Interaxis Alignment Error

±0.1 Degrees

Cross-Axis Sensitivity2

±1 %

NOISE PERFORMANCE

POWER SUPPLY

TEMPERATURE

Operating Temperature Range

−40 +105

°C

SPECIFICATIONS

TA = −40°C to +105°C, VS = V

Table 1.

Parameter1 Test Conditions/Comments Min Typ Max Unit

SENSOR INPUT Each axis

Measurement Range User selectable ±0.5, ±1, ±2, ±4 g
Nonlinearity Percentage of full scale ±0.5 %

OUTPUT RESOLUTION Each axis

All g Ranges Default resolution 10 Bits
±0.5 g Range Full resolution enabled 10 Bits
±1 g Range Full resolution enabled 11 Bits
±2 g Range Full resolution enabled 12 Bits
±4 g Range Full resolution enabled 13 Bits

SENSITIVITY Each axis

Sensitivity at X
±0.5 g, 10-bit or full resolution 921 1024 1126 LSB/g
±1 g, 10-bit resolution 460 512 563 LSB/g
±2 g, 10-bit resolution 230 256 282 LSB/g
±4 g, 10-bit resolution 115 128 141 LSB/g
Sensitivity Change Due to Temperature ±0.01 %/°C

0 g BIAS LEVEL Each axis

Initial 0 g Output T = 25°C, X
T = 25°C, Z
0 g Output Drift over Temperature −40°C < T < +105°C, X

−40°C < T < +105°C, Z
0 g Offset Tempco X
Z

OUT

, Y

, Z

Any g-range, full resolution mode 1024 LSB/g

OUT

OUT

= 3.3 V, a cceleration = 0 g, unless otherwise noted.

DD I/O

, Y

±50 mg

OUT

OUT

±75 mg

OUT

, Y

referenced to initial 0 g output −125 +125 mg

OUT

OUT,

, referenced to initial 0 g output −200 +200 mg

OUT

, Y

±0.5 mg/°C

OUT

OUT

±0.75 mg/°C

OUT

Noise Density X-, Y-axes 150 µg/√Hz
Z-axis 250 µg/√Hz
RMS Noise X-, Y-axes, 100 Hz output data rate (ODR) 1.5 mg rms
Z-axis, 100 Hz ODR 2.5 mg rms

OUTPUT DATA RATE/BANDWIDTH User selectable

Measurement Rate3 6.25 3200 Hz

SELF TEST4 Data rate ≥ 100 Hz, 2.0 V ≤ VS ≤ 3.6 V

Output Change in X-Axis 0.20 2.36 g
Output Change in Y-Axis −2.36 −0.20 g
Output Change in Z-Axis 0.30 3.70 g

Operating Voltage Range (VS) 2.0 3.6 V
Interface Voltage Range (V

) 1.7 VS V

DD I/O

Supply Current Data rate > 100 Hz 100 170 300 µA
Data rate < 10 Hz 30 55 110 µA
Standby Mode Leakage Current T = 25°C 0.1 2 µA
Over entire operating temperature range 10 μA
Turn-On (Wake-Up) Time5 1.4 ms

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. C | Page 3 of 28

ADXL313 Data Sheet

whichever is less

Output Short-Circuit Duration

Indefinite

ABSOLUTE MAXIMUM RATINGS

Table 2.

Parameter Rating

Acceleration

Any Axis, Unpowered 10,000 g

Any Axis, Powered 10,000 g
VS −0.3 V to +3.9 V
V

−0.3 V to +3.9 V

DD I/O

All Other Pins −0.3 V to V

(Any Pin to Ground)
Temperature Range

Powered −40°C to +125°C

Storage −40°C to +125°C

+ 0.3 V or 3.9 V,

DD I/O

Stresses at or above those listed under Absolute Maximum
Ratings may cause permanent damage to the product. This is a
stress rating only; functional operation of the product at these
or any other conditions above those indicated in the operational
section of this specification is not implied. Operation beyond
the maximum operating conditions for extended periods may
affect product reliability.

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 θJA θJC Unit

32-Lead LFCSP Package 27.27 30 °C/W

ESD CAUTION

Rev. C | Page 4 of 28

Data Sheet ADXL313

NOTES

1. NC = NO CONNECT. DO NOT CONNECT

TO THIS PIN.

2. THE EXPOSED PAD MUST BE SOLDERED TO THE GROUND PLANE.

24

SDA/SDI/SDIO

23

SDO/A

L

T ADDRESS

22

RESERVED

21

INT2

20

INT1

19

NC

18

NC

17

NC

1
2
3
4
5
6
7
8

GND

RESERVED

GND
GND

V

S

CS

RESERVED

NC

9

10

11

12

13

14

15

16

NCNCNCNCNCNCNC

NC

32313029282726

25

NC

V

DD I/O

NCNCNCNCSCL/SCLK

NC

T

OP

VIEW

(Not to S cale)

ADXL313

11469-002

21

INT2

Interrupt 2 Output.

22

RESERVED

Reserved. This pin must be connected to GND or left open.

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

Figure 2. Pin Configuration

Table 4. Pin Function Descriptions

Pin No. Mnemonic Description

1 GND This pin must be connected to ground.
2 RESERVED Reserved. This pin must be connected to VS or left open.
3 GND This pin must be connected to ground.
4 GND This pin must be connected to ground.
5 VS Supply Voltage.
6

CS

Chip Select.
7 RESERVED Reserved. This pin must be left open.
8 to 19 NC No Connect. Do not connect to this pin.

20 INT1 Interrupt 1 Output.

23 SDO/ALT ADDRESS Serial Data Output/Alternate I2C Address Select.
24 SDA/SDI/SDIO Serial Data (I2C)/Serial Data Input (SPI 4-Wire)/Serial Data Input/Output (SPI 3-Wire).
25 NC No Connect. Do not connect to this pin.
26 SCL/SCLK I2C Serial Communications Clock/SPI Serial Communications Clock.
27 to 30 NC No Connect. Do not connect to this pin.
31 V

Digital Interface Supply Voltage.

DD I/O

32 NC No Connect. Do not connect to this pin.
EP Exposed Pad. The exposed pad must be soldered to the ground plane.

Rev. C | Page 5 of 28

ADXL313 Data Sheet

–125

–100

–75

–50

–25

0

25

50

75

100

125

10

30 50

70 90 110

ACCELERATION (mg)

TEMPERA

TURE (°C)

11469-003

–50 –30

–10

–125

–100

–75

–50

–25

0

25

50

75

100

125

–50 –30 –10 10 30 50 70 90 110

ACCELERATION (mg)

TEMPERATURE (°C)

11469-004

–200

–150

–100

–50

0

50

100

150

200

10 30 50

70 90 110

ACCELERATION (mg)

TEMPERA

TURE (°C)

11469-005

–50 –30 –10

–1.0

–0.5

0

0.5

1.0

–40

–30

–20

–10

0

10

20

30

40

0

500

1000

1500

2000

NONLINEARIT

Y

(%FS)

NONLINEARITY (mg

)

INPUT

ACCELER

A

TION (m

g

)

11469-006

–2000 –1500

–1000

–500

–1.0

–0.5

0

0.5

1.0

–40

–30

–20

–10

0

10

20

30

40

–2000 –1500

–1000 –500

0

500

1000 1500

2000

NONLINEARITY

(%FS)

NONLINEARITY (m

g)

INPUT

ACCELERA

TION (m

g)

1

1469-007

–1.0

–0.5

0

0.5

1.0

–40

–30

–20

–10

0

10

20

30

40

0 500 1000 1500

2000

NONLINEARIT

Y (%FS)

NONLINEARITY

(mg)

INPUT ACCELERATION (mg

)

1

1469-008

–2000 –1500

–1000

–500

TYPICAL PERFORMANCE CHARACTERISTICS

Figure 3. X-Axis Acceleration vs. Temperature, Three Lots (N = 80)

Figure 4. Y-Axis Acceleration vs. Temperature, Three Lots (N = 80)

Figure 6. X-Axis Nonlinearity, ±2 g Input Range

Figure 7. Y-Axis Nonlinearity, ±2 g Input Range

Figure 5. Z-Axis Acceleration vs. Temperature, Three Lots (N = 80)

Figure 8. Z-Axis Nonlinearity, ±2 g Input Range

Rev. C | Page 6 of 28

Data Sheet ADXL313

–5

–4

–3

–2

–1

0

1

2

3

4

5

–1000 –750 –500 –250 0 250 500 750 1000

MICROLINEARITY (%)

INPUT ACCELERATION (mg)

11469-009

–5

–4

–3

–2

–1

0

1

2

3

4

5

–1000 –750 –500

–250 0 250 500 750

1000

MICROLINEARITY (%)

INPUT ACCELERATION (mg)

11469-010

–5

–4

–3

–2

–1

0

1

2

3

4

5

–1000 –750 –500 –250 0 250 500 750 1000

MICROLINEARITY (%)

INPUT ACCELERATION (mg)

11469-011

0

10

20

40

30

50

80

70

60

305070

90110

130

150

170

190

210

230

250

270

290

310

CURRENT (nA)

PERCENT OF POPUL

ATION (%)

1

1469-1

18

0

5

10

20

15

25

35

30

100

120

140

160

180

200

220

240

260

280

300

CURRENT CONSUMP TION (µA)

PERCENT OF POPULATION (%)

11469-119

0

50

100

150

200

2.0 2.4 2.8 3.2 3.6

SUPPLY VOLTAGE (V)

SUPPLY CURRENT (µA)

11469-233

Figure 9. X-Axis Microlinearity, 50 mg Step Size

Figure 12. Standby Mode Current Consumption, VS = V

= 3.3 V, 25°C

DD I/O

Figure 10. Y-Axis Microlinearity, 50 mg Step Size

Figure 11. Z-Axis Microlinearity, 50 mg Step Size

Figure 13. Current Consumption, Measurement Mode, Data Rate = 100 Hz,

V

= V

= 3.3 V, 25°C

S

DD I/O

Figure 14. Supply Current vs. Supply Voltage, V

at 25°C

S

Rev. C | Page 7 of 28

ADXL313 Data Sheet

Bandwidth (Hz)

Rate Code

IDD (µA)

on the communication bus. Minimize the duration of this state during power-up to prevent a conflict.

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. Phase­sensitive demodulation is used to determine the magnitude and
polarity of the acceleration.

POWER SEQUENCING

Power can be applied to VS or V
damaging the ADXL313. All possible power-on modes are
summarized in Table 5. The interface voltage level is set with
the interface supply voltage, V
ensure that the ADXL313 does not create a conflict on the
communication bus. For single-supply operation, V
the same as the main supply, V
however, V

can differ from VS to accommodate the desired

DD I/O

interface voltage, as long as V
After V

is applied, the device enters standby mode, where power

S

consumption is minimized and the device waits for V
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.

in any sequence without

DD I/O

, which must be present to

DD I/O

DD I/O

. In a dual-supply application,

S

is greater than or equal to V

S

DD I/O

can be

.

DD I/O

to be

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 V

Table 5. Current Consumption vs. Data Rate
(T

= 25°C, VS = V

A

Output Data
Rate (Hz)

3200 1600 1111 170
1600 800 1110 115
800 400 1101 170
400 200 1100 170
200 100 1011 170
100 50 1010 170
50 25 1001 115
25 12.5 1000 82

12.5 6.25 0111 65

6.25 3.125 0110 57

DD I/O

Bandwidth (Hz) Rate Code IDD (µA)

Table 6. Current Consumption vs. Data Rate, Low Power Mode
(T

= 25°C, VS = V

A

Output Data
Rate (Hz)

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

DD I/O

of 3.3 V.

S

= 3.3 V)

= 3.3 V)

Table 7. Power Sequencing

Condition VS V

Power Off Off Off The device is completely off, but there is a potential for a communication bus conflict.
Bus Disabled On Off The device is on in standby mode, but communication is unavailable, and the device creates a conflict

Bus Enabled Off On No functions are available, but the device does not create a conflict on the communication bus.
Standby or

Measurement

On On The device is in standby mode, awaiting a command to enter measurement mode, and all sensor

Description

DD I/O

functions are off. After the device is instructed to enter measurement mode, all sensor functions are
available.

Rev. C | Page 8 of 28

Data Sheet ADXL313

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 V

of 3.3 V.

S

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.

Rev. C | Page 9 of 28