Analog Devices ADXL202 10 b Datasheet

Low Cost ⴞ2 g/ⴞ10 g Dual Axis

iMEMS

®

Accelerometers

a

FEATURES
2-Axis Acceleration Sensor on a Single IC Chip
Measures Static Acceleration as Well as Dynamic

Acceleration
Duty Cycle Output with User Adjustable Period
Low Power <0.6 mA
Faster Response than Electrolytic, Mercury or Thermal

Tilt Sensors
Bandwidth Adjustment with a Single Capacitor Per Axis
5 m

g

Resolution at 60 Hz Bandwidth
+3 V to +5.25 V Single Supply Operation
1000

g

Shock Survival

APPLICATIONS
2-Axis Tilt Sensing
Computer Peripherals
Inertial Navigation
Seismic Monitoring
Vehicle Security Systems
Battery Powered Motion Sensing

with Digital Output

ADXL202/ADXL210

GENERAL DESCRIPTION

The ADXL202/ADXL210 are low cost, low power, complete
2-axis accelerometers with a measurement range of either

±2 g/±10 g. The ADXL202/ADXL210 can measure both dy-

namic acceleration (e.g., vibration) and static acceleration (e.g.,
gravity).

The outputs are digital signals whose duty cycles (ratio of pulse­width to period) are proportional to the acceleration in each of
the 2 sensitive axes. These outputs may be measured directly
with a microprocessor counter, requiring no A/D converter or
glue logic. The output period is adjustable from 0.5 ms to 10 ms
via a single resistor (R
voltage output proportional to acceleration is available from the
X

FILT

and Y

pins, or may be reconstructed by filtering the

FILT

duty cycle outputs.

The bandwidth of the ADXL202/ADXL210 may be set from

0.01 Hz to 5 kHz via capacitors C

floor is 500 µg/√Hz allowing signals below 5 mg to be resolved

for bandwidths below 60 Hz.

The ADXL202/ADXL210 is available in a hermetic 14-lead

Surface Mount CERPAK, specified over the 0°C to +70°C
commercial or –40°C to +85°C industrial temperature range.

). If a voltage output is desired, a

SET

and CY. The typical noise

X

C

DC

i

MEM

S

is a registered trademark of Analog Devices, Inc.

+3.0V TO +5.25V

V

DD

X SENSOR

OSCILLATOR

Y SENSOR

FUNCTIONAL BLOCK DIAGRAM

C

COM

V

DEMOD

DEMOD

X

X

FILT

FILT

Y

FILT

FILT

C

Y

DD

R
32kV

R
32kV

SELF TEST

ADXL202/
ADXL210

DUTY

CYCLE

MODULATOR

(DCM)

T2

R

SET

T1

A(g) = (T1/T2 – 0.5)/12.5%
0

g

= 50% DUTY CYCLE

T2 = R

/125MV

SET

T2

X OUT

Y OUT

C
O
U

mP

N
T
E
R

REV. B

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
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.

AIN2 =

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] World Wide Web Site: http://www.analog.com
Fax: [phone] © Analog Devices, Inc., 1999

ADXL202/ADXL210–SPECIFICATIONS

(TA = T
R

to T

MIN

= 125 k⍀, Acceleration = 0 g, unless otherwise noted)

SET

, TA = +25ⴗC for J Grade only, VDD = +5 V,

MAX

ADXL202/JQC/AQC ADXL210/JQC/AQC

Parameter Conditions Min Typ Max Min Typ Max Units

SENSOR INPUT Each Axis

Measurement Range
Nonlinearity Best Fit Straight Line 0.2 0.2 % of FS
Alignment Error

Alignment Error X Sensor to Y Sensor ±0.01 ±0.01 Degrees

Transverse Sensitivity

1

2

3

±1.5 ±2 ±8 ±10 g

±1 ±1 Degrees
±2 ±2%

SENSITIVITY Each Axis

Duty Cycle per g T1/T2 @ +25°C 10 12.5 15 3.2 4.0 4.8 %/g

Sensitivity, Analog Output At Pins X
Temperature Drift

4

∆ from +25°C ±0.5 ±0.5 % Rdg

FILT

, Y

FILT

312 100 mV/g

ZERO g BIAS LEVEL Each Axis

0 g Duty Cycle T1/T2 25 50 75 42 50 58 %

Initial Offset ±2 ±2 g

0 g Duty Cycle vs. Supply 1.0 4.0 1.0 4.0 %/V
0 g Offset vs. Temperature

NOISE PERFORMANCE

Noise Density

5

4

∆ from +25°C 2.0 2.0 mg/°C

@ +25°C 500 1000 500 1000 µg/√Hz

FREQUENCY RESPONSE

3 dB Bandwidth Duty Cycle Output 500 500 Hz
3 dB Bandwidth At Pins X

FILT

, Y

FILT

55kHz

Sensor Resonant Frequency 10 14 kHz

FILTER

R

Tolerance 32 kΩ Nominal ±15 ±15 %

FILT

Minimum Capacitance At X

FILT

, Y

FILT

1000 1000 pF

SELF TEST

Duty Cycle Change Self-Test “0” to “1” 10 10 %

DUTY CYCLE OUTPUT STAGE

F

SET

F

Tolerance R

SET

= 125 kΩ 0.7 1.3 0.7 1.3 kHz

SET

Output High Voltage I = 25 µAV

125 MΩ/R

– 200 mV VS – 200 mV mV

S

SET

125 MΩ/R

SET

Output Low Voltage I = 25 µA 200 200 mV
T2 Drift vs. Temperature 35 35 ppm/°C

Rise/Fall Time 200 200 ns

POWER SUPPLY

Operating Voltage Range 3.0 5.25 2.7 5.25 V
Specified Performance 4.75 5.25 4.75 5.25 V
Quiescent Supply Current 0.6 1.0 0.6 1.0 mA
Turn-On Time

6

To 99% 160 C

+ 0.3 160 C

FILT

+ 0.3 ms

FILT

TEMPERATURE RANGE

Operating Range JQC 0 +70 0 +70 °C
Specified Performance AQC –40 +85 –40 +85 °C

NOTES

1

For all combinations of offset and sensitivity variation.

2

Alignment error is specified as the angle between the true and indicated axis of sensitivity.

3

Transverse sensitivity is the algebraic sum of the alignment and the inherent sensitivity errors.

4

Specification refers to the maximum change in parameter from its initial at +25 °C to its worst case value at T

5

Noise density (µg/√Hz) is the average noise at any frequency in the bandwidth of the part.

6

C

in µF. Addition of filter capacitor will increase turn on time. Please see the Application section on power cycling.

FILT

All min and max specifications are guaranteed. Typical specifications are not tested or guaranteed.
Specifications subject to change without notice.

MIN

to T

MAX

.

–2–

REV. B

ADXL202/ADXL210

14
13
12
11
10

9
8

1
2
3
4

7

6

5

TOP VIEW

(Not to Scale)

A

Y

A

X

NC = NO CONNECT

NC

Y

FILT

X

FILT

V

DD

V

DD

V

TP

ST

COM

NC

Y

OUT

X

OUT

T2

NC

COM

ADXL202/

ADXL210

TYPICAL OUTPUT AT PIN:
9 = 50% DUTY CYCLE
10 = 62.5% DUTY CYCLE
11 = 2.5V
12 = 2.188V

TYPICAL OUTPUT AT PIN:
9 = 62.5% DUTY CYCLE
10 = 50% DUTY CYCLE
11 = 2.188V
12 = 2.5V

TYPICAL OUTPUT AT PIN:
9 = 37.5% DUTY CYCLE
10 = 50% DUTY CYCLE
11 = 2.812V
12 = 2.5V

TYPICAL OUTPUT AT PIN:
9 = 50% DUTY CYCLE
10 = 37.5% DUTY CYCLE
11 = 2.5V
12 = 2.812V

EARTH'S SURFACE

1

g

WARNING!

ESD SENSITIVE DEVICE

ABSOLUTE MAXIMUM RATINGS*

Acceleration (Any Axis, Unpowered for 0.5 ms) . . . . . . 1000 g

Acceleration (Any Axis, Powered for 0.5 ms) . . . . . . . . . 500 g

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +7.0 V

+V

S

Output Short Circuit Duration

(Any Pin to Common) . . . . . . . . . . . . . . . . . . . . . . Indefinite

Operating Temperature . . . . . . . . . . . . . . . . . –55°C to +125°C

Storage Temperature . . . . . . . . . . . . . . . . . . . –65°C to +150°C

*Stresses above those listed under Absolute Maximum Ratings may cause perma-

nent damage to the device. This is a stress rating only; the functional operation of
the device at these or any other conditions above those indicated in the operational
sections of this specification is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect device reliability.

Drops onto hard surfaces can cause shocks of greater than 1000 g
and exceed the absolute maximum rating of the device. Care
should be exercised in handling to avoid damage.

PIN FUNCTION DESCRIPTIONS

Pin Name Description

1 NC No Connect
2V

TP

Test Point, Do Not Connect
3 ST Self Test
4 COM Common
5 T2 Connect R

to Set T2 Period

SET

6 NC No Connect
7 COM Common
8 NC No Connect
9Y
10 X
11 Y
12 X
13 V
14 V

OUT

OUT

FILT

FILT

DD

DD

Y Axis Duty Cycle Output

X Axis Duty Cycle Output

Connect Capacitor for Y Filter

Connect Capacitor for X Filter

+3 V to +5.25 V, Connect to 14

+3 V to +5.25 V, Connect to 13

PIN CONFIGURATION

Figure 1 shows the response of the ADXL202 to the Earth’s
gravitational field. The output values shown are nominal. They
are presented to show the user what type of response to expect
from each of the output pins due to changes in orientation with
respect to the Earth. The ADXL210 reacts similarly with out­put changes appropriate to its scale.

PACKAGE CHARACTERISTICS

Package ␪

14-Lead CERPAK 110°C/W 30°C/W 5 Grams

CAUTION

ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection.
Although the ADXL202/ADXL210 features proprietary ESD protection circuitry, permanent
damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper
ESD precautions are recommended to avoid performance degradation or loss of functionality.

JA

␪

JC

Device Weight

Figure 1. ADXL202/ADXL210 Nominal Response Due to
Gravity

ORDERING GUIDE

g Temperature Package Package

Model Range Range Description Option

ADXL202JQC ±20°C to +70°C 14-Lead CERPAK QC-14
ADXL202AQC ±2 –40°C to +85°C 14-Lead CERPAK QC-14
ADXL210JQC ±10 0°C to +70°C 14-Lead CERPAK QC-14
ADXL210AQC ±10 –40°C to +85°C 14-Lead CERPAK QC-14

–3–REV. B

ADXL202/ADXL210

TEMPERATURE – 8C

4%

3%

–4%

–40

8525

0%

–1%

–2%

–3%

2%

1%

CHANGE IN SENSITIVITY

g

/DUTY CYCLE OUTPUT

20

6

0

–0.87g

PERCENTAGE OF SAMPLES

–0.64g –0.41g –0.17g 0.06g 0.29g 0.52g 0.75g

18

8

4

2

14

10

16

12

TYPICAL CHARACTERISTICS

1.06

1.04

1.02

1.00

0.98

0.96

PERIOD NORMALIZED TO 1 AT 25 8C

0.94
–45 90–30

–150 1530456075

TEMPERATURE – 8C

(@ +25ⴗC R

= 125 k⍀, VDD = +5 V, unless otherwise noted)

SET

Figure 2. Normalized DCM Period (T2) vs. Temperature

0.8

0.6

g

0.4

0.2

Figure 5. Typical X Axis Sensitivity Drift Due to
Temperature

3

C

= 0.01mF

2

FILT

0

OFFSET SHIFT IN

–0.2

g

–0.4

ZERO

–0.6

–0.8

–40 90–30

Figure 3. Typical Zero g Offset vs. Temperature

0.7

0.6

0.5

0.4

0.3

0.2

SUPPLY CURRENT – mA

0.1

0

–40 100–20

Figure 4. Typical Supply Current vs. Temperature

–20–100 1020304050 607080

TEMPERATURE – 8C

VS = 5 VDC

VS = 3.5 VDC

020406080

TEMPERATURE – 8C

–4–

VOLTS

1

0

0 0.4 0.8 1.2 1.4

FREQUENCY – ms

Figure 6. Typical Turn-On Time

Figure 7. Typical Zero g Distribution at +25°C

REV. B