ANALOG DEVICES ADXRS649 Service Manual

Fast Starting, ±20,000°/sec

F

V

FEATURES

High vibration rejection over wide frequency
Ultrafast startup: 3 ms
Measurement range extendable to ±50,000°/sec
10,000 g powered shock survivability
Ratiometric to referenced supply
5 V single-supply operation
Z-axis (yaw rate) response

−40°C to +105°C operation
Self-test on digital command
Ultrasmall and light (<0.15 cc, <0.5 gram)
Temperature sensor output
RoHS compliant

APPLICATIONS

Sports equipment
Industrial applications
Platform stabilization
High speed tachometry

Vibration Rejecting Rate Gyro

ADXRS649

GENERAL DESCRIPTION

The ADXRS649 is a complete angular rate sensor (gyroscope)
that uses the Analog Devices, Inc., patented high volume BiMOS
surface-micromachining process to make a complete gyro on
one chip. An advanced, differential, quad sensor design rejects
the influence of linear acceleration, enabling the ADXRS649
to offer rate sensing in harsh environments where shock and
vibration are present.

The output signal, RATEOUT (B1, A2), is a voltage proportional
to the angular rate about the axis normal to the top surface of
the package. The output is ratiometric with respect to a provided
reference supply. An external capacitor is used to set the band­width. The measurement range is extendable to ±50,000°/sec
by adding an external resistor.

Low power consumption (3.5 mA) enables very low power
consumption, and ultrafast startup (3 ms) allows for quick
power cycling of the gyro. At 10 samples per second, a pair of
CR2032 coin cells can power the ADXRS649 for three months.

A temperature output is provided for compensation techniques.
Two digital self-test inputs electromechanically excite the sensor
to test proper operation of both the sensor and the signal condi­tioning circuits. The ADXRS649 is available in a 7 mm × 7 mm ×
3 mm CBGA chip scale package.

FUNCTIONAL BLOCK DIAGRAM

5V

AV

CC

100nF

AGND

5V

V

DD

100n

Rev. A

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rights of third parties that may result from its use. Specifications subject to change without notice. No
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Trademarks and registered trademarks are the property of their respective owners.

PGND

DRIVE

CP1

AMP

ST2 ST1

SELF-TEST

MECHANICAL

SENSOR

CHARGE PUMP

AND VOLTAG E

REGULATO R

CP2 CP3

22nF

CP4 CP5

22nF

5

(ADC REF)

TEMP

V

RATIO

25kΩ

25k

Ω

AT 25° C

AC

AMP

SUMJ RATEOUT

2.2nF
C

OUT

VGA

R

OUT

180kΩ ±1%

100nF

ADXRS649

DEMOD

09573-001

Figure 1.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] ©2010–2011 Analog Devices, Inc. All rights reserved.

ADXRS649

TABLE OF CONTENTS

Features .............................................................................................. 1

Applications ....................................................................................... 1

General Description ......................................................................... 1

Functional Block Diagram .............................................................. 1

Revision History ............................................................................... 2

Specifications ..................................................................................... 3

Absolute Maximum Ratings ............................................................ 4

Rate Sensitive Axis ....................................................................... 4

ESD Caution .................................................................................. 4

Pin Configuration and Function Descriptions ............................. 5

REVISION HISTORY

3/11—Rev. 0 to Rev. A

Changes to Ordering Guide ............................................................ 1

12/10—Revision 0: Initial Version

Typical Performance Characteristics ..............................................6

Theory of Operation .........................................................................9

Setting the Bandwidth ..................................................................9

Temperature Output and Calibration ...................................... 10

Modifying the Measurement Range ........................................ 10

Null Bias Adjustment ................................................................. 10

Self-Test Function ...................................................................... 10

Continuous Self-Test .................................................................. 10

Outline Dimensions ....................................................................... 11

Ordering Guide .......................................................................... 11

Rev. A | Page 2 of 12

ADXRS649

SPECIFICATIONS

All minimum and maximum specifications are guaranteed. Typical specifications are not guaranteed.

T

= −40°C to +105°C, VS = AVCC = VDD = V

A

unless otherwise noted.

Table 1.

Parameter Test Conditions/Comments Min Typ Max Unit

SENSITIVITY1 Clockwise rotation is positive output

Measurement Range2 Full-scale range over specifications range ±20,000 °/sec
Initial and over Temperature

−40°C to +105°C 0.08 0.1 0.12 mV/°/sec
Temperature Drift3 ±2 %
Nonlinearity Best fit straight line 0.1 % of FS

NULL BIAS1

Null Bias −40°C to +105°C 2.4 2.5 2.6 V
Calibrated Null Bias4 −40°C to +105°C ±5 °/sec
Linear Acceleration Effect Any axis 0.1 °/sec/g
Vibration Rectification 40 g rms, 50 Hz to 27 kHz 0.0006 °/sec/g2

NOISE PERFORMANCE

Rate Noise Density TA = 25°C 0.25 °/sec/√Hz
T

A

Resolution Floor TA = 25°C, 1 minute to 1 hour in-run 200 °/hr

FREQUENCY RESPONSE

Bandwidth

5

±3 dB user adjustable up to specification 2000 Hz

Sensor Resonant Frequency 16 18 20 kHz

SELF-TEST1

ST1 RATEOUT Response

ST1 pin from Logic 0 to Logic 1 −1300 °/sec
ST2 RATEOUT Response ST2 pin from Logic 0 to Logic 1 1300 °/sec
ST1 to ST2 Mismatch6
Logic 1 Input Voltage 3.3 V
Logic 0 Input Voltage 1.7 V
Input Impedance To common 40 50 100 kΩ

TEMPERATURE SENSOR1

V

at 25°C Load = 10 MΩ 2.3 2.4 2.5 V

OUT

Scale Factor7 T
Load to V

S

A

25 kΩ
Load to Common 25 kΩ

TURN-ON TIME4 Power on to ±90% of final output, CP5 = 2.2 nF 3 ms
OUTPUT DRIVE CAPABILITY

Current Drive For rated specifications 200 μA
Capacitive Load Drive 1000 pF

POWER SUPPLY

Operating Voltage (VS) 4.75 5.00 5.25 V
Quiescent Supply Current 3.5 mA

TEMPERATURE RANGE

Specified Performance −40 +105 °C

1

Parameter is linearly ratiometric with V

2

Measurement range is the maximum range possible, including output swing range, initial offset, sensitivity, offset drift, and sensitivity drift at 5 V supplies.

3

From +25°C to −40°C or +25°C to +105°C.

4

Based on characterization.

5

Adjusted by external capacitor, C

6

Self-test mismatch is described as (ST2 + ST1)/((ST2 − ST1)/2).

7

Scale factor for a change in temperature from 25°C to 26°C. V

.

RATIO

. Reducing bandwidth below 0.01 Hz does not result in further noise improvement.

OUT

= 5 V, angular rate = 0°/sec, bandwidth = 80 Hz (C

RATIO

= 0.01 μF), I

OUT

= 100 μA, ±1 g,

OUT

= 105°C 0.4 °/sec/√Hz

= 25°C, V

= 5 V 9 mV/°C

RATIO

is ratiometric to V

TEMP

. See the section for more information. Temperature Output and Calibration

RATIO

±2

%

Rev. A | Page 3 of 12

ADXRS649

ABSOLUTE MAXIMUM RATINGS

Table 2.

Parameter Rating

Acceleration (Any Axis, 0.5 ms)

Unpowered 10,000 g
Powered 10,000 g

VDD, AV

CC

V

AVCC

RATIO

−0.3 V to +6.0 V

ST1, ST2 AVCC
Output Short-Circuit Duration

Indefinite

(Any Pin to Common)
Operating Temperature Range −55°C to +125°C
Storage Temperature Range −65°C to +150°C

Stresses above those listed under the 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.

Drops onto hard surfaces can cause shocks of greater than
10,000 g and can exceed the absolute maximum rating of the
device. Care should be exercised in handling to avoid damage.

RATE SENSITIVE AXIS

The ADXRS649 is a z-axis rate-sensing device (also called a yaw
rate-sensing device). It produces a positive going output voltage
for clockwise rotation about the axis normal to the package top,
that is, clockwise when looking down at the package lid.

RATE

AXIS

LONGIT UDINAL

AXIS

ABCD G

A1

LATERAL AXIS

Figure 2. RATEOUT Signal Increases with Clockwise Rotation

EF

+

1

A

VCC=5V

7

V

GND

RATIO

RATEOUT

/2

4.75V

RATE IN

0.25V

09573-002

ESD CAUTION

Rev. A | Page 4 of 12