ultra low-power high performance 3-axis “femto” accelerometer
LGA-14
(2.0x2.0x1mm)
Features
■ Wide supply voltage, 1.71 V to 3.6 V
■ Independent IOs supply (1.8 V) and supply
voltage compatible
■ Ultra low-power mode consumption down to 2
µA
■ ±2g/±4g/±8g/±16g dynamically selectable full
scale
2
■ I
C/SPI digital output interface
■ 8-bit data output
■ 2 independent programmable interrupt
generators for free-fall and motion detection
■ 6D/4D orientation detection
■ “Sleep to wake” and “Return to sleep” function
■ Free-fall detection
■ Motion detection
■ Embedded temperature sensor
■ Embedded FIFO
■ ECOPACK
Applications
®
RoHS and “Green” compliant
LIS2DM
MEMS digital output motion sensor:
The LIS2DM has dynamically user selectable full
scales of ±2g/±4g/±8g/±16g and it is capable of
measuring accelerations with output data rates
from 1 Hz to 5.3 kHz.
The self-test capability allows the user to check
the functioning of the sensor in the final
application.
The device may be configured to generate
interrupt signals by two independent inertial
wake-up/free-fall events as well as by the position
of the device itself.
The LIS2DM is available in a small thin plastic
land grid array package (LGA) and is guaranteed
to operate over an extended temperature range
from -40 °C to +85 °C.
■ Motion activated functions
■ Display orientation
■ Shake control
■ Pedometer
■ Gaming and virtual reality input devices
■ Impact recognition and logging
Description
Table 1.Device summary
Order
codes
LIS2DM-40 to +85LGA-14Tray
LIS2DMTR-40 to +85LGA-14
Temperature
range [° C]
PackagePackaging
Tape and
reel
The LIS2DM is an ultra low-power high
performance 3-axis linear accelerometer
belonging to the “femto” family, with digital I
C serial data (SDA)
SPI serial data input (SDI)
3-wire interface serial data output (SDO)
SPI serial data output (SDO)
I2C less significant bit of the device address (SA0)
SPI enable
2
I
C/SPI mode selection (1: SPI idle mode / I2C communication
enabled; 0: SPI communication mode / I
2
C disabled)
12-14ResConnect to GND
Doc ID 022536 Rev 19/47
Mechanical and electrical specificationsLIS2DM
2 Mechanical and electrical specifications
2.1 Mechanical characteristics
@ Vdd = 2.5 V, T = 25 °C unless otherwise noted
Table 3.Mechanical characteristics
SymbolParameterTest conditionsMin.Typ.
FS bit set to 00±2.0
FS bit set to 01±4.0
FSMeasurement range
SoSensitivity
TCSo
Ty O ff
TCOff
Vst
To p
1. Typical specifications are not guaranteed.
2. Verified by wafer level test and measurement of initial offset and sensitivity.
3. Typical zero-g level offset value after MSL3 preconditioning.
4. Offset can be eliminated by enabling the built-in high pass filter.
5. The sign of “Self-test output change” is defined by CTRL_REG4 ST bit, for all axes.
“Self-test output change” is defined as the absolute value of:
6.
OUTPUT[LSb]
7. After enabling self-test, the correct data is obtained after two samples.
Sensitivity change vs.
temperature
Ty p i c a l ze ro -
g level
offset accuracy
Zero-
g level change
vs. temperature
Self-test
output change
Operating
temperature range
(Self test enabled)
(2)
FS bit set to 10±8.0
FS bit set to 11±16.0
FS bit set to 00;
Low power mode
FS bit set to 01;
Low power mode
FS bit set to 10;
Low power mode
FS bit set to 11;
Low power mode
FS bit set to 000.01%/°C
(3),(4)
FS bit set to 00±100mg
Max. delta from 25 °C±1m
FS bit set to 00 X axis; 690LSb
(5),(6),(7)
FS bit set to 00 Y axis; 690LSb
FS bit set to 00 Z axis;690LSb
- OUTPUT[LSb]
(Self test disabled)
. 1LSb=16mg at 8-bit representation, ±2 g full-scale.
(a)
.
(1)
16
32
64
192
-40+85°C
Max.Unit
g
mg/digit
g/°C
a. The product is factory calibrated at 2.5 V. The operational power supply range is from 1.71V to 3.6 V.
10/47Doc ID 022536 Rev 1
LIS2DMMechanical and electrical specifications
2.2 Temperature sensor characteristics
@ Vdd =2.5 V, T=25 °C unless otherwise noted
Table 4.Temperature sensor characteristics
SymbolParameterTest conditionMin.Typ.
(b)
.
(1)
Max.Unit
TSDr
TODRTemperature refresh rateODR
Temperature sensor output
change vs. temperature
1digit/°C
(3)
Top Operating temperature range-40+85°C
1. Typical specifications are not guaranteed.
2. 8-bit resolution.
3. Refer to Table 27.
2.3 Electrical characteristics
@ Vdd =2.5 V, T=25 °C unless otherwise noted
Table 5.Electrical characteristics
SymbolParameterTest conditionsMin.Typ.
VddSupply voltage1.712.53.6V
Vdd_IOI/O pins supply voltage
Idd
IddPdn
Current consumption in Normal
mode
Current consumption in power
down mode
VIHDigital high level input voltage0.8*Vdd_IOV
(2)
50 Hz ODR6µA
(c)
.
(1)
Max.Unit
1.71Vdd+0.1V
0.5µA
(2)
Hz
VILDigital low level input voltage0.2*Vdd_IOV
VOHHigh level output voltage0.9*Vdd_IOV
VOLLow level output voltage0.1*Vdd_IOV
TopOperating temperature range-40+85
1. Typical specification are not guaranteed.
2. It is possible to remove Vdd maintaining Vdd_IO without blocking the communication busses, in this condition the
measurement chain is powered off.
b. The product is factory calibrated at 2.5 V. Temperature sensor operation is guaranteed in the range 2 V - 3.6 V.
c. The product is factory calibrated at 2.5 V. The operational power supply range is from 1.71 V to 3.6 V.
Doc ID 022536 Rev 111/47
°C
Mechanical and electrical specificationsLIS2DM
SPC
CS
SDI
SDO
t
su(CS)
t
v(SO)
t
h(SO)
t
h(SI)
t
su(SI)
t
h(CS)
t
dis(SO)
t
c(SPC)
MSB IN
MSB OUT
LSB OUT
LSB IN
(3)
(3)
(3)
(3)
(3)
(3)
(3)
(3)
2.4 Communication interface characteristics
2.4.1 SPI - serial peripheral interface
Subject to general operating conditions for Vdd and Top.
Table 6.SPI slave timing values
(1)
Val u e
SymbolParameter
Min.Max.
tc(SPC)SPI clock cycle100ns
fc(SPC)SPI clock frequency10MHz
tsu(CS)CS setup time5
th(CS)CS hold time10
tsu(SI)SDI input setup time5
th(SI)SDI input hold time15
tv(SO)SDO valid output time50
th(SO)SDO output hold time5
tdis(SO)SDO output disable time50
Unit
ns
1. Values are guaranteed at 10 MHz clock frequency for SPI with both 4 and 3 wires, based on characterization results, not
tested in production.
(d)
Figure 3.SPI slave timing diagram
3.When no communication is ongoing, data on SDO is driven by internal pull-up resistors.
12/47Doc ID 022536 Rev 1
d. Measurement points are done at 0.2·Vdd_IO and 0.8·Vdd_IO, for both input and output ports.
LIS2DMMechanical and electrical specifications
SPC
CS
SDI
SDO
t
su(CS)
t
v(SO)
t
h(SO)
t
h(SI)
t
su(SI)
t
h(CS)
t
dis(SO)
t
c(SPC)
MSB IN
MSB OUT
LSB OUT
LSB IN
(3)
(3)
(3)
(3)
(3)
(3)
(3)
(3)
2.4.2 I2C - Inter IC control interface
Subject to general operating conditions for Vdd and top.
Table 7.I2C slave timing values
SymbolParameter
I2C standard mode
(1)
I2C fast mode
Min.Max.Min.Max.
(1)
Unit
f
(SCL)
t
w(SCLL)
t
w(SCLH)
t
su(SDA)
t
h(SDA)
t
r(SDA) tr(SCL)
t
f(SDA) tf(SCL)
t
h(ST)
t
su(SR)
t
su(SP)
t
w(SP:SR)
SCL clock frequency01000400kHz
SCL clock low time4.71.3
SCL clock high time4.00.6
SDA setup time250100ns
SDA data hold time03.450.010.9µs
SDA and SCL rise time1000
SDA and SCL fall time300
START condition hold time40.6
Repeated START condition
setup time
4.70.6
STOP condition setup time40.6
Bus free time between STOP
and START condition
4.71.3
1. Data based on standard I2C protocol requirement, not tested in production.
2. Cb = total capacitance of one bus line, in pF.
Figure 4.I
2
C Slave timing diagram
(e)
20 + 0.1C
20 + 0.1C
µs
(2)
b
(2)
b
300
ns
300
µs
e. Measurement points are done at 0.2·Vdd_IO and 0.8·Vdd_IO, for both ports.
Doc ID 022536 Rev 113/47
Mechanical and electrical specificationsLIS2DM
This is a mechanical shock sensitive device, improper handling can cause permanent
damage to the part.
This is an ESD sensitive device, improper handling can cause permanent damage to
the part.
2.5 Absolute maximum ratings
Stresses above those listed as “absolute maximum ratings” may cause permanent damage
to the device. This is a stress rating only and functional operation of the device under these
conditions is not implied. Exposure to maximum rating conditions for extended periods may
affect device reliability.
Table 8.Absolute maximum ratings
SymbolRatingsMaximum valueUnit
VddSupply voltage-0.3 to 4.8V
Vdd_IOI/O pins supply voltage-0.3 to 4.8V
Vin
A
POW
A
UNP
T
T
STG
ESDElectrostatic discharge protection 2 (HBM)kV
Input voltage on any control pin
(CS, SCL/SPC, SDA/SDI/SDO, SDO/SA0)
Acceleration (any axis, powered, Vdd = 2.5 V)
Acceleration (any axis, unpowered)
Operating temperature range-40 to +85°C
OP
Storage temperature range-40 to +125°C
-0.3 to Vdd_IO +0.3V
3000 g for 0.5 ms
10000 g for 0.1 ms
3000 g for 0.5 ms
10000 g for 0.1 ms
Note:Supply voltage on any pin should never exceed 4.8 V
14/47Doc ID 022536 Rev 1
LIS2DMMechanical and electrical specifications
2.6 Terminology and functionality
Terminology
2.6.1 Sensitivity
Sensitivity describes the gain of the sensor and can be determined e.g. by applying 1 g
acceleration to it. As the sensor can measure DC accelerations this can be done easily by
pointing the axis of interest towards the center of the earth, noting the output value, rotating
the sensor by 180 degrees (pointing to the sky) and noting the output value again. By doing
so, ±1 g acceleration is applied to the sensor. Subtracting the larger output value from the
smaller one, and dividing the result by 2, leads to the actual sensitivity of the sensor. This
value changes very little over temperature and also time. The sensitivity tolerance describes
the range of Sensitivities of a large population of sensors.
2.6.2 Zero-g level
Zero-g level offset (TyOff) describes the deviation of an actual output signal from the ideal
output signal if no acceleration is present. A sensor in steady-state on a horizontal surface
measures 0 g in the X axis and 0 g in the Y axis whereas the Z axis measures 1 g. The
output is ideally in the middle of the dynamic range of the sensor (content of OUT registers
00h, data expressed as 2’s complement number). A deviation from the ideal value in this
case is called Zero-g offset. Offset is to some extent a result of stress to the MEMS sensor
and therefore the offset can slightly change after mounting the sensor onto a printed circuit
board or exposing it to extensive mechanical stress. Offset changes little over temperature,
see Table 3: Mechanical characteristics. The Zero-g level tolerance (TyOff) describes the
standard deviation of the range of Zero-g levels of a population of sensors.
Functionality
2.6.3 Normal mode
The LIS2DM provides a single operating mode called normal mode.
Ta bl e 9 summarizes operating mode performances.
Table 9.Normal mode features
Operating mode
Normal modeODR/2116
BW
[Hz]
Turn-on time
[ms]
So @ ±2g
[mg/digit]
Doc ID 022536 Rev 115/47
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