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 LT1102 High Speed, Precision, JFET Input Instrumentation Amplifier (Fixed Gain = 10 or 100)
FEATURES

DESCRIPTIO
Slew Rate: 30V/s Gain-Bandwidth Product: 35MHz Settling Time (0.01%): 3s Overdrive Recovery: 0.4s Gain Error: 0.05% Max Gain Drift: 5ppm/C Gain Nonlinearity: 16ppm Max Offset Voltage (Input + Output): 600V Max - Drift with Temperature: 2V/C Input Bias Current: 40pA Max Input Offset Current: 40pA Max - Drift with Temperature (to 70C): 0.5pA/C
The LT (R)1102 is the first fast FET input instrumentation amplifier offered in the low cost, space saving 8-pin packages. Fixed gains of 10 and 100 are provided with excellent gain accuracy (0.01%) and non-linearity (3ppm). No external gain setting resistor is required. Slew rate, settling time, gain-bandwidth product, overdrive recovery time are all improved compared to competitive high speed instrumentation amplifiers. Industry best speed performance is combined with impressive precision specifications: less than 10pA input bias and offset currents, 180V offset voltage. Unlike other FET input instrumentation amplifiers, on the LT1102 there is no output offset voltage contribution to total error, and input bias currents do not double with every 10C rise in temperature. Indeed, at 70C ambient temperature the input bias current is only 40pA.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
APPLICATIO S

Fast Settling Analog Signal Processing Multiplexed Input Data Acquisition Systems High Source Impedance Signal Amplification from High Resistance Bridges, Capacitance Sensors, Photodetector Sensors Bridge Amplifier with < 1Hz Lowpass Filtering
TYPICAL APPLICATIO
Wideband Instrumentation Amplifier with 150mA Output Current
V+ = 15V 6 5 R 7 LT1102 3 4 8
LT1010
OUT
-
1
2
V
- = - 15V
OUTPUT = 10V INTO 75 TO 330kHz (R = 50) 10V INTO 200 TO 330kHz (R = 200) DRIVES 2.2nF CAP LOAD GAIN = 10, DEGRADED 0.01% DUE TO LT1010
LT1102 * TA01
5V/DIV
+
BIAS
G = 10
U
Slew Rate FPO
0.5s/DIV
FPOLT1102 * TA02
U
U
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1
LT1102
ABSOLUTE
AXI U
RATI GS
Supply Voltage ...................................................... 20V Differential Input Voltage ....................................... 40V Input Voltage ......................................................... 20V
Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: http://www.linear.com/leadfree/
PACKAGE/ORDER I FOR ATIO
TOP VIEW OUTPUT 8
ORDER PART NUMBER
GROUND (REF) 1 REF 2 G = 10 OUT G = 10 90R 7 R
+ -
6 +IN
9R -IN 3
+ -
9 = 1.8k 5 V+ V- 4 N8 PACKAGE 8-LEAD PDIP
TJMAX = 100C, JA = 130C/W
4 V - (CASE)
H PACKAGE 8-LEAD TO-5 METAL CAN
J8 PACKAGE 8-LEAD CERDIP
OBSOLETE PACKAGE
Consider the N8 Package for Alternate Source
OBSOLETE PACKAGE
Consider the N8 Package for Alternate Source
Consult LTC Marketing for parts specified with wider operating temperature ranges.
2
+ -
+ -
90R R
9R
LT1102AMH LT1102MH LT1102ACH LT1102CH
U
U
W
WW
U
W
(Note 1)
Output Short-Circuit Duration .......................... Indefinite Operating Temperature Range LT1102I .............................................. -40C to 85C LT1102AC/LT1102C ................................ 0C to 70C LT1102AM/LT1102M (OBSOLETE).....-55C to 125C Storage Temperature Range ................. -65C to 150C Lead Temperature (Soldering, 10 sec).................. 300C
TOP VIEW GROUND (REF) 1 90R REF 2 G = 10 9R LT1102 8 OUTPUT 90R 7 R R 9R OUT G = 10
ORDER PART NUMBER LT1102IN8 LT1102ACN8 LT1102CN8
-IN 3
6 +IN
5 V+
LT1102MJ8 LT1102CJ8
LT1102 * POI01
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LT1102
ELECTRICAL CHARACTERISTICS
SYMBOL GE GNL PARAMETER Gain Error Gain Nonlinearity CONDITIONS
VS = 15V, VCM = 0V, TA = 25C, Gain = 10 or 100, unless otherwise noted.
MIN LT1102AM/AC TYP MAX 0.010 3 8 7 180 3 3 0.050 14 20 16 600 40 40 MIN LT1102M/I/C TYP MAX 0.012 4 8 7 200 4 4 1012 1011 1012 2.8 30 4 10.5 82 86 5.0 13.0 12.0 100 1.7 10 18 37 20 2 11.5 97 101 3.4 13.5 13.0 220 3.5 17 30 400 4.0 6.5 13 18 1.8 3.0 7 9 4.0 6.5 13 18 5.6 5 0.070 18 25 30 900 60 60 UNITS % ppm ppm ppm V pA pA

VO = 10V, RL = 50k or 2k G = 100, RL = 50k G = 100, RL = 2k G = 10, RL = 50k or 2k
VOS IOS IB
Input Offset Voltage Input Offset Current Input Bias Current Input Resistance Common Mode Differential Mode VCM = - 11V to 8V VCM = 8V to 11V 0.1Hz to 10Hz fO = 10Hz fO = 1000Hz (Note 2) fO = 1000Hz, 10Hz (Note 3) 10.5 1k Source Imbalance, VCM = 10.5V VS = 9V to 18V 84 88
1012 1011 1012 2.8 37 19 1.5 11.5 98 102 3.3
en
Input Noise Voltage Input Noise Voltage Density Input Noise Current Density lnput Voltage Range
VP-P nV/Hz nV/Hz fA/Hz V dB dB mA V V kHz MHz V/s V/s ns s s s s
CMRR PSRR IS VO BW SR
Common Mode Rejection Ratio Power Supply Rejection Ratio Supply Current Maximum Output Voltage Swing Bandwidth Slew Rate Overdrive Recovery Settling Time
RL = 50k RL = 2k G = 100 (Note 4) G = 10 (Note 4) G = 100, VIN = 0.13V, VO = 5V G = 10, VIN = 1V, VO = 5V 50% Overdrive (Note 5) VO = 20V Step (Note 4) G = 10 to 0.05% G = 10 to 0.01% G = 100 to 0.05% G = 100 to 0.01%
13.0 12.0 120 2.0 12 21
13.5 13.0 220 3.5 17 30 400 1.8 3.0 7 9
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3
LT1102
ELECTRICAL CHARACTERISTICS
SYMBOL GE TCGE GNL PARAMETER Gain Error Gain Error Drift (Note 6) Gain Nonlinearity CONDITIONS G = 100, VO = 10V, RL = 50k or 2k G = 10, VO = 10V, RL = 50k or 2k G = 100, RL = 50k or 2k G = 10, RL = 50k or 2k G = 100, RL = 50k G = 100, RL = 2k G = 10, RL = 50k or 2k (Note 6)
-40C TA 85C for I grades, unless otherwise noted.
VS = 15V, VCM = 0V, Gain = 10 or 100, -55C TA 125C for AM/M grades,
LT1102AM TYP MAX 0.10 0.05 9 5 20 28 9 300 2 0.3 2 0.25 0.12 20 10 70 85 20 1400 8 4 10 80 84 LT1102M/I TYP MAX 0.10 0.06 10 6 24 32 9 400 3 0.4 2.5 96 99 2.5 12.5 12.0 13.2 12.6 0.30 0.15 25 14 90 110 24 2000 12 6 15
MIN
MIN
UNITS % % ppm/C ppm/C ppm ppm ppm V V/C nA nA dB dB mA V V
VOS VOS/T lOS IB CMRR PSRR IS VO
Input Offset Voltage Input Offset Voltage Drift Input Offset Current Input Bias Current Common Mode Rejection Ratio Power Supply Rejection Ratio Supply Current Maximal Output Voltage Swing VCM = 10.3V VS = 10V to 17V TA = 125C RL = 50k RL = 2k 12.5 12.0 82 88
97 100 2.5 13.2 12.6
VS = 15V, VCM = 0V, Gain = 10 or 100, 0C TA 70C, unless otherwise noted.
SYMBOL GE TCGE GNL PARAMETER Gain Error Gain Error Drift (Note 6) Gain Nonlinearity CONDITIONS G = 100, VO = 10V, RL = 50k or 2k G = 10, VO = 10V, RL = 50k or 2k G = 100, RL = 50k or 2k G = 10, RL = 50k or 2k G = 100, RL= 50k G = 100, RL= 2k G = 10, RL= 50k or 2k (Note 6) (Note 6) (Note 6) VCM = 10.3V VS = 10V to 17V TA = 70C RL = 50k RL = 2k 12.8 12.0 83 87 MIN LT1102AC TYP MAX 0.04 0.03 8 5 8 11 8 230 2 10 0.5 40 1 98 101 2.8 13.4 12.8 12.8 12.0 0.11 0.09 18 10 30 36 18 1000 8 150 3 300 4 81 85 MIN LT1102C TYP MAX 0.05 0.04 9 6 9 12 8 280 3 15 0.5 50 1 97 100 2.9 13.4 12.8 0.14 0.12 22 14 40 48 22 1400 12 220 4 400 6 UNITS % % ppm/C ppm/C ppm ppm ppm V V/C pA pA/C pA pA/C dB dB mA V V
VOS VOS/T IOS IOS/T IB IB/T CMRR PSRR IS VO
Input Offset Voltage Input Offset Voltage Drift Input Offset Current Input Offset Current Drift Input Bias Current lnput Bias Current Drift Common Mode Rejection Ratio Power Supply Rejection Ratio Supply Current Maximum Output Voltage Swing
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4
LT1102
ELECTRICAL CHARACTERISTICS
Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: This parameter is tested on a sample basis only. Note 3: Current noise is calculated from the formula: in = (2qIB)1/2 where q = 1.6 * 10-19 coulomb. The noise of source resistors up to 1G swamps the contribution of current noise. Note 4: This parameter is not tested. It is guaranteed by design and by inference from the slew rate measurement. Note 5: Overdrive recovery is defined as the time delay from the removal of an input overdrive to the output's return from saturation to linear operation. 50% overdrive equals VIN = 2V (G = 10) or VIN = 200mV (G = 100). Note 6: This parameter is not tested. It is guaranteed by design and by inference from other tests.
TYPICAL PERFOR A CE CHARACTERISTICS
Small Signal Response, G = 10 (Input = 50mV Pulse) Small Signal Response, G = 100 (Input = 5mV Pulse) Slew Rate, G = 100 (Input = 130mV Pulse)
100mV/DIV
100mV/DIV
2S/DIV
FPOLT1102 * TPC01
2S/DIV
FPOLT1102 * TPC02
5V/DIV
Settling Time, G = 10 (Input From - 10V to 10V)
5mV/DIV AT SUM NODE
1S/DIV
FPOLT1102 * TPC04
5mV/DIV AT SUM NODE
Settling Time, G = 100 (Input From - 10V to 10V)
5mV/DIV AT SUM NODE
5mV/DIV AT SUM NODE
UW
FPOLT1102 * TPC06
2S/DIV
FPOLT1102 * TPC03
Settling Time, G = 10 (Input From 10V to -10V)
1S/DIV
FPOLT1102 * TPC05
Settling Time, G = 100 (Input From 10V to -10V)
2S/DIV
FPOLT1102 * TPC07
2S/DIV
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5
LT1102 TYPICAL PERFOR A CE CHARACTERISTICS
Capacitive Load Handling
120 100
OVERSHOOT (%)
VS = 15V TA = 25C
OUTPUT IMPEDANCE ()
G = 10 G = 100
GAIN ERROR (%)
80 60 40 20 0 0.1
1 10 100 CAPACITIVE LOAD (nF)
Undistorted Output vs Frequency
30
RMS VOLTAGE NOISE DENSITY (nVHz)
INPUT BIAS CURRENT, TA = 125C (nA)
PEAK-TO-PEAK OUTPUT SWING (V)
VS = 15V TA = 25C
20
G = 100 RL = 2k OR 50k
10
G = 10 RL = 2k
G = 10 RL = 50k
0 10k
100k 1M FREQUENCY (Hz)
Warm-Up Drift
50 CHANGE IN OFFSET VOLTAGE (V) VS = 15V TA = 25C
COMMON MODE RANGE (V)
40
12 11 10 -11 -12 -13 -14
SUPPLY CURRENT (mA)
30
N PACKAGE
20 H AND J PACKAGE 10
0
0
1 3 4 2 TIME AFTER POWER ON (MINUTES)
LT1102 * TPC14
6
UW
LT1102 * TPC08
LT1102 * TPC11
Output Impedance vs Frequency
100 VS = 15V TA = 25C
0.5
Gain vs Frequency
0 -0.5 G = 100 VS = 15V TA = 25C 40
G = 100
10 G = 10
-1.0 -1.5 0 G = 10 -0.5 -1.0
30
GAIN (dB)
1
20
10 100k 1M FREQUENCY (Hz) 10M
LT1102 * TPC10
0.1
1000
1k
10k 100k FREQUENCY (Hz)
1M
LT1102 * TPC09
-1.5 10k
Voltage Noise vs Frequency
100 70 50 40 30 20 1/f CORNER = 28Hz VS = 15V TA = 25C 2.6 2.4 2.2 2.0 1.8 1.6 1.4 1.2 1.0
Input Bias Current Over the Common Mode Range
VS = 15V 160 140 120 TA = 125C 100 80 60 TA = 70C TA = 25C 40 20 0 -20 -5 -10 0 5 10 COMMON MODE VOLTAGE (V) 15
INPUT BIAS CURRENT, TA = 25C TO 70C (pA)
10
10M
3
10
30
100
300
1k
3k
10k
0.8 -15
FREQUENCY (Hz)
LT1102 * TPC12
LT1102 * TPC13
Common Mode Range vs Temperature
15 14 13
Supply Current vs Temperature
6
VS = 15V G = 10
G = 100
4
VS = 15V VS = 10V
2
G = 10 OR 100
5
-15 -50
50 0 TEMPERATURE (C)
100
LT1102 * TPC15
0 -50 -25
50 25 75 0 TEMPERATURE (C)
100
125
LT1102 * TPC16
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LT1102 TYPICAL PERFOR A CE CHARACTERISTICS
Short-Circuit Current vs Time
50 40
SHORT-CIRCUIT CURRENT (mA)
30 20 10 0 -10 -20 - 30 -40 -50
VS = 15V
TA = 125C TA = 125C TA = 25C TA = -55C
PERCENT OF UNITS
2 0 1 3 TIME FROM OUTPUT SHORT TO GROUND (MINUTES)
LT1102 * TPC17
Gain Error vs Temperature
0.10 VS = 15V RL 2k G = 100
GAIN NONLINEARITY (ppm)
0.08
GAIN ERROR (%)
0.06
0.04 G = 10 0.02
0 -50 -25
50 25 0 75 TEMPERATURE (C)
UW
Distribution of Offset Voltage
35 30 25 20 15 10 5 0 -0.8 -0.4 0.4 0.8 0 INPUT OFFSET VOLTAGE (mV)
LT1102 * TPC18
TA = -55C TA = 25C
VS = 15V TA = 25C
950 UNITS TESTED IN ALL PACKAGES
Gain Nonlinearity Over Temperature
40
32 G = 100 RL = 50k G = 10 RL = 2k OR 50k G = 100 RL = 2k
24
16
8
100
125
-50 -25
50 25 0 75 TEMPERATURE (C)
100
125
LT1102 * TPC19
LT1102 * TPC20
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7
LT1102
APPLICATIO S I FOR ATIO
In the two op amp instrumentation amplifier configuration, the first amplifier is basically in unity gain, and the second amplifier provides all the voltage gain. In the LT1102, the second amplifier is decompensated for gain of 10 stability, therefore high slew rate and bandwidth are achieved. Common mode rejection versus frequency is also optimized in the G = 10 mode, because the bandwidths of the two op amps are similar. When G = 100, this statement is no longer true; however, by connecting an 18pF capacitor between pins 1 and 2, a common mode AC gain is created to cancel the inherent roll-off. From 200Hz to 30kHz, CMRR versus frequency is improved by an order of magnitude. Input Protection Instrumentation amplifiers are often used in harsh environments where overload conditions can occur. The LT1102 employs FET input transistors, consequently the differential input voltage can be 30V (with 15V supplies, 36V with 18V supplies). Some competitive instrumentation amplifiers have NPN inputs which are protected by back-to-back diodes. When the differential input Voltage exceeds 13V on these competitive devices, input current increases to milliampere level; more than 10V differential voltage can cause permanent damage. When the LT1102 inputs are pulled below the negative supply or above the positive supply, the inputs will clamp a diode voltage below or above the supplies. No damage will occur if the input current is limited to 20mA.
COMMON MODE REJECTION RATIO (dB)
8
U
Common Mode Rejection Ratio vs Frequency
120 100 80 60 40 20 0
W
UU
G = 10
G = 100 18pF PIN 1 TO PIN 2 G = 100
VS = 15V TA = 25C
1 10 100 1k 10k FREQUENCY (Hz) 100k 1M
LT1102 * AI01
Gains Between 10 and 100 Gains between 10 and 100 can be achieved by connecting two equal resistors (= RX) between pins 1 and 2 and pins 7 and 8. Gain = 10 + RX R + RX/90
The nominal value of R is 1.84k. The usefulness of this method is limited by the fact that R is not controlled to better than 10% absolute accuracy in production. However, on any specific unit, 90R can be measured between Pins 1 and 2.
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LT1102
APPLICATIO S I FOR ATIO
Differential Output
6
Gain = 20, 110, or 200 Instrumentation Amplifiers Single Ended Output
+
LT1102 8 6
+
IN
3
-
1
-
6
+
LT1102 8 3
3
-
1 GAIN = 200, AS SHOWN GAIN = 20, SHORT PIN 1 TO PIN 2, PIN 7 TO PIN 8 ON BOTH DEVICES GAIN = 110, SHORT PIN 1 TO PIN 2, PIN 7 TO PIN 8 ON ONE DEVICE, NOT ON THE OTHER INPUT REFERRED NOISE IS REDUCED BY 2 (G = 200 OR 20)
LT1102 * AI02
Multiplexed Input Data Acquisition
509 OR EQUIVALENT S1A 4 CHANNELS OF DIFFERENTIAL INPUT S4A S1B S4B DECODER AO A1 EN
LT1102 * AI03
800kHz SIGNALS CAN BE MULTIPLEXED WITH LT1102 IN G = 10
Voltage Programmable Current Source is Simple and Precise
VIN 0 10V
+
LT1006
-
0.05F
10k
+
LT1102 A = 100 R 10*
IK
IK =
-
LOAD
LT1102 * AI04
U
+
LT1102 3 8 OUT
W
UU
-
+
OUT
+
IN
1
-
-
6
+
LT1102 8
-
1
DA
+
LT1102 OUTPUT
DB
-
Dynamic Response of the Current Source
A = 5V/DIV
B = 5mA/DIV
VIN R * 100
HORIZ. = 20s/DIV
FPOLT1102 * AI05
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9
LT1102
TYPICAL APPLICATIO S
Basic Connections
V+ 5 6 INPUT 3 NC
Settling Time Test Circuit
15V 6 R1 5.1k HP5082-2810 100
+ -
4 -15V
LT1102 3 1
20VP-P FLAT-TOP INPUT
R1 = 910, G = 10 R1 = 10k, G = 100
LT1102 * TA04
10
U
+
LT1102
7 8 1 4 OUT
-
2 NC
V- REF GAIN = 100 V+ 5
6 INPUT 3
+
LT1102
7 8 OUT
-
2 1
4 V- REF
GAIN = 10
LT1102 * TA03
Offset Nulling
15V 2k 6
8 200
5
+ -
4
5 LT1102 8 OUT 10k R2
3
1
1.8k
5.0k FET PROBE
2k
- 15V R2 = 3.3, G = 10 R2 = 30, G = 100 NULL RANGE = 1mV GAIN DEGRADATION 0.018%
LT1102 * TA05
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LT1102
PACKAGE DESCRIPTIO
.045 - .068 (1.143 - 1.650) FULL LEAD OPTION .300 BSC (7.62 BSC)
.008 - .018 (0.203 - 0.457)
NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS
Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
U
H Package 8-Lead TO-5 Metal Can (.230 Inch PCD)
(Reference LTC DWG # 05-08-1321)
.335 - .370 (8.509 - 9.398) DIA .305 - .335 (7.747 - 8.509) .040 (1.016) MAX .050 (1.270) MAX GAUGE PLANE .165 - .185 (4.191 - 4.699) REFERENCE PLANE .500 - .750 (12.700 - 19.050) SEATING PLANE .010 - .045* (0.254 - 1.143) .016 - .021** (0.406 - 0.533) .027 - .045 (0.686 - 1.143) 45TYP .028 - .034 (0.711 - 0.864) PIN 1 .230 (5.842) TYP .110 - .160 (2.794 - 4.064) INSULATING STANDOFF *LEAD DIAMETER IS UNCONTROLLED BETWEEN THE REFERENCE PLANE AND THE SEATING PLANE .016 - .024 **FOR SOLDER DIP LEAD FINISH, LEAD DIAMETER IS (0.406 - 0.610) H8 (TO-5) 0.230 PCD 0801
J8 Package 8-Lead CERDIP (Narrow .300 Inch, Hermetic)
(Reference LTC DWG # 05-08-1110)
CORNER LEADS OPTION (4 PLCS) .405 (10.287) MAX 8 7 6 5
.005 (0.127) MIN
.023 - .045 (0.584 - 1.143) HALF LEAD OPTION
.025 (0.635) RAD TYP 1 2 3
.220 - .310 (5.588 - 7.874)
4
.200 (5.080) MAX .015 - .060 (0.381 - 1.524)
0 - 15
.045 - .065 (1.143 - 1.651) .014 - .026 (0.360 - 0.660) .100 (2.54) BSC
.125 3.175 MIN
J8 0801
OBSOLETE PACKAGES
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11
LT1102
PACKAGE DESCRIPTIO U
N8 Package 8-Lead PDIP (Narrow .300 Inch)
(Reference LTC DWG # 05-08-1510)
.400* (10.160) MAX 8 7 6 5 .255 .015* (6.477 0.381) 1 .300 - .325 (7.620 - 8.255) 2 3 4 .130 .005 (3.302 0.127) .045 - .065 (1.143 - 1.651) .065 (1.651) TYP .120 (3.048) .020 MIN (0.508) MIN .018 .003 (0.457 0.076)
N8 1002
.008 - .015 (0.203 - 0.381) +.035 .325 -.015 8.255 +0.889 -0.381
(
)
.100 (2.54) BSC
INCHES MILLIMETERS *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm)
NOTE: 1. DIMENSIONS ARE
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12
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 FAX: (408) 434-0507
LT 0507 REV B * PRINTED IN USA
www.linear.com
(c) LINEAR TECHNOLOGY CORPORATION 1991


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