SILICON DESIGNS, INC
!
SENSOR:
Capacitive Micromachined
Nitrogen Damped
Hermetically Sealed
!
Digital Pulse Density Output
!
Fully Calibrated
!
Responds to DC & AC Acceleration
!
-55 to +125
E
C Operation
!
+5 VDC, 2 mA Power (typical)
!
Non-Standard g Ranges Available
!
Integrated Sensor & Amplifier
!
LCC or J-Lead Surface
Mount Package
!
Serialized for Traceability
!
TTL/CMOS Compatible
!
No External Reference Voltage
!
Easy Interface to Microprocessors
!
Good EMI Resistance
!
RoHS Compliant
Model 1010
DIGITAL ACCELEROMETER
ORDERING INFORMATION
Full Scale
Acceleration
±2 g
±5 g
±10 g
±25 g
±50 g
±100 g
±200 g
Hermetic Packages
20 pin LCC
20 pin JLCC
1010L-002
1010J-002
1010L-005
1010J-005
1010L-010
1010J-010
1010L-025
1010J-025
1010L-050
1010J-050
1010L-100
1010J-100
1010L-200
1010J-200
DESCRIPTION
The Model 1010 is a low-cost, integrated accelerometer for use in zero to medium frequency instrumentation
applications. Each miniature, hermetically sealed package combines a micro-machined capacitive sense element
and a custom integrated circuit that includes a sense amplifier and sigma-delta A/D converter. It is relatively
insensitive to temperature changes and gradients. Each device is marked with a serial number on its bottom surface
for traceability. An optional calibration test sheet (1010-TST) is also available which lists the measured bias, scale
factor, linearity, operating current and frequency response.
OPERATION
The Model 1010 produces a digital pulse train in which the density of pulses (number of pulses per second) is
proportional to applied acceleration. It requires a single +5 volt power supply and a TTL/CMOS level clock of 100kHz-
1MHz. The output is ratiometric to the clock frequency and independent of the power supply voltage. Two forms of
digital signals are provided for direct interfacing to a microprocessor or counter. The sensitive axis is perpendicular
to the bottom of the package, with positive acceleration defined as a force pushing on the bottom of the package.
External digital line drivers can be used to drive long cables or when used in an electrically noisy environment.
APPLICATIONS
COMMERCIAL
!
Automotive
Air Bags
Active Suspension
Adaptive Brakes
Security Systems
!
Shipping Recorders
!
Appliances
INDUSTRIAL
!
Vibration Monitoring
!
Vibration Analysis
!
Machine Control
!
Modal Analysis
!
Robotics
!
Crash Testing
!
Instrumentation
Silicon Designs, Inc.
!
1445 NW Mall Street, Issaquah, WA 98027-5344
!
Phone: 425-391-8329
!
Fax: 425-391-0446
web site:
www.silicondesigns.com
[page 1]
Mar 07
Model
1010
Digital Accelerometer
SIGNAL DESCRIPTIONS
V
DD
and GND (power):
Pin 14 (V
DD
) & pin 19 (GND). Additionally tie pins 3 & 11 to V
DD
& pins 2, 5, 6 & 18 to GND.
CLK (input):
Pin 8. Reference clock input. This hysteresis threshold input must be driven by a 50% duty cycle square wave
signal. Factory Calibration is performed at 250 kHz which is the recommended clock frequency for best results. Operation
at frequencies as low as 100 kHz or as high as 1 MHz are possible, however a slight bias shift may result.
CNT (output):
Pin 10. Count output. A return-to-zero type digital
pulse stream whose pulse width is equal to the input CLK logic
high time. The CNT pulse rate increases with positive
acceleration.
The device experiences positive (+1g)
acceleration with its lid facing up in the earth’s gravitational
field.
___
signal is meant to drive an up-counter directly.
This
DIR and DIR (output):
Pins 12 & 16 respectively. Direction output. This output is updated at the fall of each clock cycle. It is
high during clock cycles when a high going CNT pulse is present and low during cycles when no CNT pulse is present. A
non-return-to-zero signal meant to control the count direction (i.e. up or down) of a counter. DIR can be low pass filtered
___
to produce an analog measure of the acceleration. DIR is the complement of DIR and is provided for use in driving
differential transmission lines.
DV (input):
Pin 4. Deflection Voltage. Normally left open. A test input that applies an electrostatic force to the sense element,
simulating a positive acceleration. The nominal voltage at this pin is
aV
DD
. DV voltages higher than required to bring the
output to positive full scale may cause device damage.
VR (input):
Pin 3. Voltage Reference. Tie directly to
V
DD
(+5V). A 0.1µF bypass capacitor is recommended at this pin.
CLK/2 (output):
Pin 15. Clock divided by 2. A buffered clock output whose frequency equals CLK divided by 2.
PERFORMANCE - by Model:
V
DD
=V
R
=5.0 VDC, F
CLK
=250kHz, T
C
=25EC.
MODEL NUMBER
Input Range
Frequency Response
(Nominal, 3 dB)
Sensitivity
(F
CLK
=250kHz)
Max. Mechanical Shock
(0.1 ms)
1010x-002 1010x-005 1010x-010 1010x-025 1010x-050 1010x-100 1010x-200
±2
±5
±10
±25
±50
±100
±200
0 - 400
0 - 600 0 - 1000 0 - 1400 0 - 1600 0 - 1800 0 - 2000
62.5
25.0
12.5
5.00
2.50
1.25
0.625
2000
5000
UNITS
g
Hz
kHz/g
g
PERFORMANCE - all Models:
Unless otherwise specified V
DD
=V
R
=5.0 VDC, F
CLK
=250kHz, T
C
=25EC.
PARAMETER
Cross Axis Sensitivity
Bias Calibration Error
1
MIN
-002
-005 thru -200
-002
-005 thru -200
Bias Temperature Shift
(T
C
= -55 to +125EC)
1
Scale Factor Calibration Error
1, 2
Scale Factor Temperature Shift
(T
C
= -55 to +125EC)
1
Non-Linearity
-002 thru -100
1, 2
(-90 to +90% of Full Scale)
-200
Power Supply Rejection Ratio (V
DD
=V
R
)
Operating Voltage (V
DD
vs
GND)
Operating Current (I
DD
+I
VR
)
1
Clock Input Voltage Range (with
respect to GND)
Mass: ‘L’ package
(add 0.06 grams for ‘J’ package)
Note 1: Tighter tolerances available on special order.
TYP
2
2
1
150
100
1
+300
0.5
0.7
MAX
3
4
2
400
300
2
1.0
1.5
5.5
3
V
DD
+0.5
UNITS
%
% of F
CLK
(span)
(ppm
of F
CLK
)/EC
%
ppm/EC
% of span
dB
Volts
mA
40
4.5
-0.5
5.0
2
Volts
0.62
grams
Note 2: 100g and greater versions are tested from -65 to +65g.
SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE
Silicon Designs, Inc.
!
1445 NW Mall Street, Issaquah, WA 98027-5344
!
Phone: 425-391-8329
!
Fax: 425-391-0446
web site:
www.silicondesigns.com
[page 2]
Mar 07
Model
1010
Digital Accelerometer
ABSOLUTE MAXIMUM RATINGS
*
Case Operating Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to +125EC
Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to +125EC
Acceleration Over-range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2000g for 0.1 ms
Voltage on V
DD
to GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to 6.5V
Voltage on Any Pin (except DV) to GND
4
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to V
DD
+0.5V
Voltage on DV to GND
5
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±15V
Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 mW
Note 4: Voltages on pins other than DV, GND or V
DD
may exceed 0.5 volt above or below the supply voltages provided the current is limited to 1 mA.
Note 5: The application of DV voltages higher than required to bring the output to positive full scale may cause device damage.
* NOTICE:
Stresses greater than those listed above may cause permanent damage to the device. These are stress ratings only.
Functional operation of the device at or above these conditions is not implied. Exposure to absolute maximum rating conditions
for extended periods may affect device reliability.
D.C. CHARACTERISTICS:
V
DD
=V
R
=5.0 VDC, T
C
= -55 to +125EC.
SYMBOL
V
T-
V
T+
V
H
V
OL
V
OH
I
I
C
IO
I
DD
+I
VR
PARAMETER
Negative Going Threshold Voltage
(CLK)
Positive Going Threshold Voltage
(CLK)
Hysteresis Voltage
(CLK)
Output Low Voltage
(CNT, DIR, CLK/2)
Output High Voltage
(CNT, DIR, CLK/2)
Input Leakage Current
(CLK)
Pin Capacitance
Operating Current
MIN
0.9
0.5
V
DD
- 0.4
10
10
3
TYP
1.7
3.0
1.3
MAX
3.7
0.4
UNITS
V
V
V
V
V
µA
pF
mA
TEST CONDITIONS
2
I
OL
= 2.0 mA
I
OH
= 2.0 mA
V
I
= 0 to V
DD
1 MHz, T
A
= 25EC
F
CLK
= 250kHz
A.C. CHARACTERISTICS:
V
DD
=V
R
=5.0 VDC, T
C
= -55 to +125EC, Load Capacitance=50pF.
PARAMETER
CLK input frequency
CLK input rise/fall time
CLK duty cycle
CLK fall to DIR fall
CLK fall to DIR rise
CLK rise to valid CNT out
CLK fall to CNT fall
CLK fall to CLK/2 rise/fall
MIN
100
45
40
40
40
40
40
TYP
250
50
85
90
90
85
90
MAX
1000
50
55
195
205
230
205
210
UNITS
kHz
ns
%
ns
ns
ns
ns
ns
+5V
11
8
14
VDD
3
VR
0.1 uF
16
DIR
12
DIR
CNT
CLK/2
10
15
COMPLEMENT OF DIR
TO PULSE COUNTER
CLOCK ÷ 2
100 kHz to 1 MHz
TEST INPUT
CLK
1010x-xxx
4
DV
GND
5
19
2
6
18
RECOMMENDED CONNECTIONS
SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE
PINOUT
(LCC & JLCC)
Silicon Designs, Inc.
!
1445 NW Mall Street, Issaquah, WA 98027-5344
!
Phone: 425-391-8329
!
Fax: 425-391-0446
web site:
www.silicondesigns.com
[page 3]
Mar 07
Model
1010
Digital Accelerometer
USING THE COUNT
(CNT)
OUTPUT:
Pulses from the
CNT
output are meant to be accumulated in a hardware counter. Each
pulse accumulation or sample, reflects the average acceleration (change in velocity) over that interval. The sample period or
“gate time” over which these pulses are accumulated determines both the bandwidth and quantization of the measurement.
Quantization (g' s)
=
g
SPAN
•
f
SR
f
CLK
f
CNT
g
FORCE
1
g
FORCE
=
f
CLK
+
2
g
SPAN
f
CNT
1
=
g
SPAN
−
f
CLK
2
Where:
g
SPAN
=
2 * (
full scale acceleration in g' s
)
f
SR
=
CNT
sample rate in Hertz
f
CLK
=
accelerometer clock rate in Hertz
f
CNT
=
CNT
pulse rate in pulses / sec
g
FORCE
=
acceleration in gravity units
1 g
=
9.8085 m / s2 or 32.180 ft / s2
The first equation above shows that as the
sample rate is reduced (i.e. a longer
sample period), the quantization becomes
finer but bandwidth is reduced.
Conversely, as the sample rate is
increased, quantization becomes coarser
but the bandwidth of the measurement is
increased. The second and third equations
show how the
CNT
pulse frequency
equates to the applied g-force. When
using a frequency counter to monitor the
CNT
output pulse rate, a counter with a DC
coupled input must be used. The
CNT
output is a return-to-zero signal whose duty
cycle varies from zero to fifty percent, from
minus full scale to positive full scale
acceleration. A frequency counter with an
AC coupled input will provide an erroneous
reading as the duty cycle varies
appreciably from fifty percent. The figure to
the left illustrates how the
CNT
and
DIR
outputs vary as the accelerometer is
subjected to accelerations from minus full
scale (-FS) to plus full scale (+FS).
DEFLECTION VOLTAGE
(DV)
TEST INPUT:
This test input applies an electrostatic
force to the sense element, simulating a positive acceleration. It has a nominal input
impedance of 32 k and a nominal open circuit voltage of
aV
DD
. For best accuracy during
normal operation, this input should be left unconnected or connected to a voltage source
equal to
a
of the
V
DD
supply. The change in output pulse rate (∆f) is proportional to the
square of the difference between the voltage applied to the
DV
input (V
DV
) and
aV
DD
. Only
positive shifts in the output pulse rate may be generated by applying voltage to the
DV
input. When voltage is applied to the
DV
input, it should be applied gradually. The
application of
DV
voltages greater than required to bring the output to positive full scale
may cause device damage. The proportionality constant (k) varies for each device and is
not characterized.
1
∆
f
≈
k
V
DV
−
V
DD
3
2
ESD and LATCH-UP CONSIDERATIONS:
The model 1010 accelerometer is a CMOS device subject to damage from large
electrostatic discharges. Diode protection is provided on the inputs and outputs but care should be exercised during handling
to assure that the device is placed only on a grounded conductive surface. Individuals and tools should be grounded before
coming in contact with the device. Do not insert the model 1010 into (or remove it from) a powered socket.
SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE
Silicon Designs, Inc.
!
1445 NW Mall Street, Issaquah, WA 98027-5344
!
Phone: 425-391-8329
!
Fax: 425-391-0446
web site:
www.silicondesigns.com
[page 4]
Mar 07
Model
1010
Digital Accelerometer
BIAS STABILITY CONSIDERATIONS
Bias temperature hysteresis can be minimized by temperature cycling your model 1010 accelerometer after it has
been soldered to your circuit board. If possible, the assembled device should be exposed to ten cycles from -40 to
+85EC minimum (-55 to +125EC recommended). The orientation to the Earth's gravitational field during temperature
cycling should preferably be in the same orientation as it will be in the final application. The accelerometer does not
need to have power applied during this temperature cycling.
PACKAGE DIMENSIONS
"L" SUFFIX PACKAGE
(20 PIN LEADLESS CERAMIC CHIP CARRIER)
*T
*M
C
F
K
DIM
A
B
C
D
E
F
G
H
J
K
L
*M
N
P
R
*T
*U
A
E
Positive
Acceleration
TERMINAL 20
TERMINAL 1
A
D
G
"J" SUFFIX PACKAGE
(20 PIN LEADED CHIP CARRIER)
R
N
INCHES
MIN
MAX
0.342 0.358
0.346 0.378
0.055 TYP
0.095 0.115
0.085 TYP
0.050 BSC
0.025 TYP
0.050 TYP
0.004 x 45°
0.010 R TYP
0.016 TYP
0.048 TYP
0.050 0.070
0.017 TYP
0.023 R TYP
0.085 TYP
0.175 TYP
MILLIMETERS
MIN
MAX
8.69
9.09
8.79
9.60
1.40 TYP
2.41
2.92
2.16 TYP
1.27 BSC
0.64 TYP
1.27 TYP
0.10 x 45°
0.25 R TYP
0.41 TYP
1.23 TYP
1.27
1.78
0.43 TYP
0.58 R TYP
2.16 TYP
4.45 TYP
*U
L
J
P
B
H
NOTES: 1. * DIMENSIONS 'M', 'T' & 'U' LOCATE ACCELERATION SENSING ELEMENT'S CENTER OF MASS .
2. LID IS ELECTRICALLY TIED TO TERMINAL 19 (GND).
3. CONTROLLING DIMENSION: INCH.
4. TERMINALS ARE PLATED WITH 60 MICRO-INCHES MIN GOLD OVER 80 MICRO-INCHES MIN NICKEL.
(THIS PLATING SPECIFICATION DOES NOT APPLY TO THE METALLIZED PIN-1 IDENTIFIER MARK ON
THE BOTTOM OF THE J-LEAD VERSION OF THE PACKAGE).
5. PACKAGE: 90% MINIMUM ALUMINA (BLACK), LID: SOLDER SEALED KOVAR.
SOLDERING RECOMMENDATIONS:
RoHS Compliance:
The model 1010 does not contain elemental lead and is RoHS compliant.
WARNING:
If no-lead solder is to be used to attach the device, we do not recommend the use of reflow soldering
methods such as vapor phase, solder wave or hot plate. These methods impart too much heat for too long of a
period of time and may cause excessive bias shifts. For no-lead soldering, we only recommend the manual "Solder
Iron Attach" method (listed on the next page of this data sheet). We also do not recommend the use of ultrasonic
bath cleaners because these models contain internal gold wires that are thermo sonically bonded.
SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE
Silicon Designs, Inc.
!
1445 NW Mall Street, Issaquah, WA 98027-5344
!
Phone: 425-391-8329
!
Fax: 425-391-0446
web site:
www.silicondesigns.com
[page 5]
Mar 07