silicon designs, inc

silicon designs, inc
SILICON DESIGNS, INC
Model 1210
ANALOG ACCELEROMETER
! SENSOR:
Capacitive Micromachined
Nitrogen Damped
Hermetically Sealed
! ±4V Differential Output or
0.5V to 4.5V Single Ended Output
! Fully Calibrated
! Responds to DC & AC Acceleration
! -55 to +125 EC Operation
! +5 VDC, 7 mA Power (typical)
! Non-Standard g Ranges Available
! Integrated Sensor & Amplifier
! LCC or J-Lead Surface
Mount Package
! Serialized for Traceability
! RoHS Compliant
DESCRIPTION
ORDERING INFORMATION
Full Scale
Acceleration
±5 g
±10 g
±25 g
±50 g
±100 g
±200 g
±400 g
Hermetic Packages
20 pin LCC
20 pin JLCC
1210L-005
1210J-005
1210L-010
1210J-010
1210L-025
1210J-025
1210L-050
1210J-050
1210L-100
1210J-100
1210L-200
1210J-200
1210L-400
1210J-400
The Model 1210 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 differential output stage. 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 (1210-TST) is also available which lists the measured bias, scale factor,
linearity, operating current and frequency response.
OPERATION
The Model 1210 produces two analog output voltages which vary with acceleration as shown in the figure below. The
outputs can be used either in differential or single ended mode referenced to +2.5 volts. Two reference voltages, +5.0
and +2.5 volts (nominal), are required; the output scale factor is ratiometric to the +5 volt reference voltage, and both
outputs at zero acceleration are equal to the +2.5 volt reference. 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.
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
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 1]
Apr 07
Model 1210 Analog Accelerometer
SIGNAL DESCRIPTIONS
VDD and GND (power): Pins (8,9,11,14) and (2,5,6,18,19) respectively. Power (+5 Volts DC) and ground.
AOP and AON (output): Pins 12 and 16 respectively. Analog output voltages proportional to acceleration. The AOP voltage
increases (AON decreases) with positive acceleration; at zero acceleration both outputs are nominally equal to the +2.5 volt
reference. The device experiences positive (+1g) acceleration with its lid facing up in the earth’s gravitational field. Either
output can be used individually or the two outputs can be used differentially but differential mode is recommended for both
lowest noise and highest accuracy operation. Voltages can be measured ratiometrically to VR for good accuracy without
requiring a precision reference voltage. (See plot.)
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 ½ VDD. 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 VDD for ratiometric measurements or to a +5V reference for better absolute
accuracy. A 0.1µF bypass capacitor is recommended at this pin.
2.5 Volt (input): Pin 17. Voltage Reference. Tie to a resistive voltage divider from +5 volts or to a +2.5 volt reference voltage.
PERFORMANCE - by Model: VDD=VR=5.0 VDC, TC=25EC.
MODEL NUMBER
1210x-005 1210x-010 1210x-025 1210x-050 1210x-100 1210x-200 1210x-400
UNITS
Input Range
±5
±10
±25
±50
±100
±200
±400
g
Frequency Response (Nominal, 3 dB) 0 - 400
0 - 600 0 - 1000 0 - 1500 0 - 2000 0 - 2500 0 - 3500
Hz
Sensitivity (Differential) 1
800
400
160
80
40
20
10
mV/g
Output Noise (Differential RMS, typical)
32
63
158
316
632
1265
2530
µg/(root Hz)
Max. Mechanical Shock (0.1 ms)
2000
5000
g
Note 1: Single ended sensitivity is half of values shown.
PERFORMANCE - all Models: Unless otherwise specified VDD=VR=5.0 VDC, TC=25EC, Differential Mode.
PARAMETER
MIN
TYP
MAX
UNITS
3
4
2
300
200
%
-005
-010 thru -400
-005
-010 thru -400
2
2
1
100
50
1
2
Scale Factor Temperature Shift (TC= -55 to +125EC) 2
-005 thru -025
-050, -100
Non-Linearity
(-90 to +90% of Full Scale) 2, 3
-200
-400
Power Supply Rejection Ratio
Output Impedance
Operating Voltage
+300
0.5
0.5
0.7
1.0
25
90
5.0
Cross Axis Sensitivity
Bias Calibration Error
2
Bias Temperature Shift
(TC= -55 to +125EC)
2
Scale Factor Calibration Error 2, 3
Operating Current (IDD+IVR)
2
Mass: ‘L’ package (add 0.06 grams for ‘J’ package)
Note 2: Tighter tolerances available on special order.
4.75
7
0.62
% of span
(ppm of span)/EC
%
ppm/EC
1.00
1.25
1.50
2.00
5.25
10
% of span
dB
Ohms
Volts
mA
grams
Note 3: 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]
Apr 07
Model 1210 Analog 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 VDD to GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to 6.5V
Voltage on Any Pin (except DV) to GND 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.5V to VDD+0.5V
Voltage on DV to GND 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±15V
Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 mW
Note 4: Voltages on pins other than DV, GND or VDD 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.
PINOUT
RECOMMENDED CONNECTIONS
(LCC & JLCC PACKAGES)
The 2.5V reference input (pin 17) may be driven from either a precision voltage source or by the capacitively
bypassed resistive divider shown above.
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 kΩ and a nominal open circuit voltage of
½ VDD. For best accuracy during normal operation, this input should be left unconnected or connected to a voltage
source equal to ½ of the VDD supply. The change in differential output voltage (AOP - AON) is proportional to the
square of the difference between the voltage applied to the DV input (VDV) and ½ VDD. Only positive shifts in the
output voltage 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.
∆ ( AOP − AON ) ≈ k (VDV − 21 VDD )
2
ESD and LATCH-UP CONSIDERATIONS: The model 1210 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 1210 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 3]
Apr 07
Model 1210 Analog Accelerometer
BIAS STABILITY CONSIDERATIONS
Bias temperature hysteresis can be minimized by temperature cycling your model 1210 accelerometer after it has
been soldered to your circuit board. If possible, the assembled device should be exposed to ten cycles from -40 to
+85 EC minimum (-55 to +125 EC 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
C
K
F
*U
L
*M
A
E
TERMINAL 20
TERMINAL 1
H
J
Positive
Acceleration
A
G
D
"J" SUFFIX PACKAGE (20 PIN LEADED CHIP CARRIER)
P
B
R
N
DIM
A
B
C
D
E
F
G
H
J
K
L
*M
N
P
R
*T
*U
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
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 1210 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 4]
Apr 07
Model 1210 Analog Accelerometer
SOLDERING RECOMMENDATIONS (continued):
Reflow of Sn62 or Sn63 type solder using a hotplate is the preferred method for assembling the model 1210 surface mount
accelerometer to your Printed circuit board. Hand soldering using a fine tipped soldering iron is possible but difficult without
a steady hand and some form of visual magnification due to the small size of the connections. When using the hand solder
iron method, it’s best to purchase the J-Leaded version (1210J) for easier visual inspection of the finished solder joints.
Pre-Tinning of Accelerometer Leads is Recommended: To prevent gold migration embrittlement of the solder joints,
it is best to pre-tin the accelerometer leads. We recommend tinning one lead at a time, to prevent excessive heating of
the accelerometer, using a fine-tipped solder iron and solder wire. The solder bath method of pre-tinning is not
recommended due to the high degree of heat the interior of the device gets subjected to which may cause permanent shifts
in the bias and/or scale factor.
Hotplate Attach Method using Solder Paste or Solder Wire: Apply solder to the circuit board’s pads using Sn62 or Sn63
solder paste or pre-tin the pads using solder and a fine tipped soldering iron. If pre-tinning with an iron, apply flux to the
tinned pads prior to placing the components. Place the accelerometer in its proper position onto the pasted or tinned pads
then place the entire assembly onto a hotplate that has been pre-heated to 250EC. Leave on hotplate only long enough
for the solder to flow on all pads (DO NOT OVERHEAT!)
Solder Iron Attach Method using Solder Paste: Apply solder paste to the circuit board’s pads where the accelerometer
will be attached. Place the accelerometer in its proper position onto the pasted pads. Press gently on the top of the
accelerometer with an appropriate tool to keep it from moving and heat one of the corner pads, then an opposite corner
pad with the soldering iron. Make sure the accelerometer is positioned so all 20 of its connections are centered on the
board’s pads. Once the two opposite corner pads are soldered, the part is secure to the board and you can work your way
around soldering the remaining 18 connections. Allow the accelerometer to cool in between soldering each pin to prevent
overheating.
Solder Iron Attach Method using Solder Wire: Solder pre-tin two opposite corner pads on the circuit board where the
accelerometer will be attached. Place the accelerometer in its proper position onto the board. Press gently on the top of
the accelerometer and heat one of the corner pads that was tinned and the part will drop down through the solder and seat
on the board. Do the same at the opposite corner pad that was tinned. Make sure the accelerometer is positioned so all
20 of its connections are centered on the board’s pads. Once the two opposite corner pads are soldered, the part is secure
to the board and you can work your way around soldering the remaining 18 connections. Allow the accelerometer to cool
in between soldering each pin to prevent overheating.
LCC & JLCC Solder Contact Plating Information: The plating composition and thickness for the solder pads and
castellations on the “L” suffix (LCC) package are 60 to 225 micro-inches thick of gold (Au) over 80 to 350 micro-inches thick
of nickel (Ni) over a minimum of 5 micro-inches thick of moly-manganese or tungsten refractory material. The leads for
the “J” suffix (JLCC) package are made of an Iron-Nickel sealing alloy and have the same gold over nickel plating
thicknesses as for the LCC pads.
Recommended Solder Pad Pattern: The recommended solder pad size and shape for both the LCC and J-LCC
packages is shown in the diagram and table below. These dimensions are recommendations only and may or may not
be optimum for your particular soldering process.
DIM
A
B
C
D
E
F
G
inch
.230
.430
.100
.033
.050
.013
.120
mm
5.84
10.92
2.54
0.84
1.27
0.33
3.05
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]
Apr 07
Model 1210 Analog Accelerometer
APPLICATION NOTE
ADDING A SINGLE ENDED OUTPUT TO THE MODEL 1210
DIFFERENTIAL OUTPUT ACCELEROMETER
R1 = R2 = 5.00K ±0.5% for precision 2.50V ref.
C1 = C2 (See below for value calculation)
R3, R4, R5 & R6 = 20kΩ to 50kΩ
R3 = R5 to within 0.1% for common mode rejection
R4 = R6 to within 0.1% for common mode rejection
R4 / R3 ratio accurate to within 0.1% for gain control
R6 / R5 ratio accurate to within 0.1% for gain control
To achieve the highest resolution and lowest noise performance from your model 1221 accelerometer module,
it should be connected to your voltage measurement instrument in a differential configuration using both the AOP and AON
output signals. If your measurement instrument lacks differential input capability or you desire to use a differential input
capable instrument in single ended mode, then the circuit above can be used to preserve the low noise performance of
the model 1221 while using a single ended type connection.
This circuit converts the ± 4 Volt differential output of the model 1210 accelerometer, centered at +2.5 Volts, to
a single ended output centered about ground (0.0 Volts). It provides the advantage of low common mode noise by
preventing the ground current of the model 1210 from causing an error in the voltage reading.
The op-amp should be located as close as possible to your voltage monitoring equipment so that the majority of
the signal path is differential. Any noise present along the differential path will affect both wires to the same degree and
the op-amp will reject this noise because it is a common mode signal. The op-amp type is not critical; a µA741 or ¼ of a
LM124 can be used. Both plus and minus supplies are needed for the op-amp to accommodate the positive and negative
swings of the single ended output signal.
For this design, always set R4 = R6, R3 = R5 and C3 = C4. The gain of the circuit is then determined by the ratio
R4/R3 . When R4 = R3 = R6 = R5, the gain equals 1 and the output swing will be ± 4 Volts single ended with respect to
ground. To obtain a ± 5 Volt single ended output, set R4/R3 = R6/R5 = 5/4 = 1.25. The single ended output of the op-amp
will be centered at ground if R4 and C3 are tied to ground; using some other fixed voltage for this reference will shift the
output. The value of the optional capacitors C3 and C4 (C3 = C4) can be selected to roll off the frequency response to the
frequency range of interest. The cutoff frequency f0 (-3 dB frequency) for this single order low pass filter is given by:
f0 =
1
2π R4 C3
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 6]
Apr 07
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement