FEATURES DESCRIPTIO TYPICAL APPLICATIO. LT1002 Dual, Matched Precision Operational Amplifier APPLICATIO S. Guaranteed low offset voltage

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1 FEATURES Guaranteed low offset voltage LT2A µv max LT2 µv max Guaranteed offset voltage match LT2A µv max LT2 8µV max Guaranteed low drift LT2A.9µV/ C max LT2.µV/ C max Guaranteed CMRR LT2A db min LT2 db min Guaranteed channel separation LT2A 2dB min LT2 db min Guaranteed matching characteristics Low noise.5µv P-P APPLICATIO S U Thermocouple Amplifiers Strain Gauge Amplifiers Low level signal processing Medical instrumentation Precision dual limit threshold detection Instrumentation amplifiers, LTC and LT are registered trademarks of Linear Technology Corporation DESCRIPTIO U LT2 Dual, Matched Precision Operational Amplifier The LT 2 dual, matched precision operational amplifiers combine excellent individual amplifier performance with tight matching and temperature tracking between amplifiers. In the design, processing, and testing of the device, particular attention has been paid to the optimization of the entire distribution of several key parameters and their matching. Consequently, the specifications of even the low cost commercial grade (LT2C) have been spectacularly improved compared to presently available devices. Essentially, the input offset voltage of all units is less than 8µV, and matching between amplifiers is consistently beter than µv (see distribution plot below). Input bias and offset currents, channel separation, common mode and power suply rejections of the LT2C are all specified at levels which were previsouly attainable only on very expensive, selected grades of other dual devices. Power dissipation is nearly halved compared to the most popular precision duals, without adversely affecting noise or speed performance. A by-product of lower dissipation is decreased warm-up drift. For even better performance in a single precision op amp, refer to the LT data sheet. A bridge signal conditioning application is shown below. This circuit illustrates the requirement for both excellent matching and individual amplifier specifications. TYPICAL APPLICATIO 8.2k 2k* LM29.99k* U Strain Gauge Signal Conditioner with Bridge Excitation LT2 5Ω BRIDGE LT2 2k IN8 IN8 2k Ω 5W 2N229 2N297 Ω 5W REFERENCE OUT TO MONITORING A/D CONVERTER k* k ZERO 2 LT *RNC FILM RESISTORS µf k* GAIN TRIM V TO V OUT.k* 2 TA NUMBER OF UNITS Distribution of Offset Voltage Match UNITS TESTED INPUT OFFSET VOLTAGE MATCH (µv) 2 TA2 2fb

2 LT2 ABSOLUTE MAXIMUM RATINGS W W W (Note ) Supply Voltage (Note 7)... ±22V Differential Input Voltage... ±V Input Voltage Equal to Supply Voltage Output Short Circuit Duration... Indefinite Operating Temperature Range LT2AM/LT2M (OBSOLETE).. 55 C to 25 C LT2AC/LT2C... C to 7 C Storage Temperature Range All Grades... 5 C to 5 C Lead Temperature (Soldering, sec.)... C U PACKAGE/ORDER INFORMATION NULL (A) NULL (A) 2 IN (A) IN (A) V (B) 5 OUT (B) V (B) 7 TOP VIEW A N PACKAGE PIN PLASTIC T JMAX = 25 C, θ JA = C/W V (A) OUT (A) 2 V (A) IN (B) IN (B) 9 NULL (B) 8 NULL (B) NOTE: Device may be operated even if insertion is reversed; this is due to inherent symmetry of pin locations of amplifiers A and B. (Note 7) B U W U ORDER PART NO. LT2ACN LT2CN OFFSET VOLTAGE MAX at 25 C µv µv J PACKAGE PIN HERMETIC T JMAX = 25 C, θ JA = C/W LT2AMJ LT2MJ LT2ACJ LT2CJ OBSOLETE PACKAGE Consider the N Package for Alternate Source µv µv µv µv Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS, I DIVIDUAL A PLIFIERS U W,, unless otherwise noted LT2AM/LT2AC LT2M/LT2C SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS V OS Input Offset Voltage (Note 2) 2 25 µv V OS Long Term Input Offset Voltage Time Stability (Notes and ) µv/month I OS Input Offset Current na I B Input Bias Current ±. ±. ±.7 ±.5 na e n Input Noise Voltage.Hz to Hz (Note ) µv p-p e n Input Noise Voltage Density f O = Hz (Note ) f O = Hz (Note ) nv Hz A VOL Large Signal Voltage Gain R L 2kΩ, V O = ±2V R L kω, V O = ±V V/mV CMRR Common Mode Rejection Ratio V CM = ±V 2 2 db PSRR Power Supply Rejection Ratio V S = ±V to ±8V db R in Input Resistance Differential Mode (Note 5) 2 8 MΩ Input Voltage Range ± ± ± ± V V OUT Maximum Output Voltage Swing R L 2kΩ ± ± ± ± V R L kω ±2 ±.5 ±2 ±.5 SR Slew Rate R L 2kΩ (Note 5) V/µs GBW Gain Bandwidth Product (Note 5) MHz P d Power Dissipation No load mw per amplifier No load, V S = ±V fb

3 ELECTRICAL CHARACTERISTICS, I DIVIDUAL A PLIFIERS U W LT2 The denotes the specifications which apply over the temperature range 55 C T A 25 C,,unless otherwise noted. LT2AM LT2M SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS V OS Input Offset Voltage (Note 2) µv V OS Average Input Offset Voltage Drift µv/ C Temp I OS Input Offset Current na I B Input Bias Current ±. ±. ±.5 ±9. na A VOL Large Signal Voltage Gain R L 2kΩ, V O = ±V V/mV CMRR Common Mode Rejection Ratio V CM = ±V 22 2 db PSRR Power Supply Rejection Ratio V S = ±V to ±8V db Input Voltage Range ± ± ± ± V V OUT Output Voltage Swing R L 2kΩ ±2.5 ±.5 ±2. ±.5 V P d Power Dissipation No load 55 9 mw per amplifier The denotes the specifications which apply over the temperature range C T A 7 C,, unless otherwise noted. LT2AC LT2C SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS V OS Input Offset Voltage (Note 2) 2 µv V OS Average Input Offset Voltage Drift µv/ C Temp I OS Input Offset Current na I B Input Bias Current ±.7 ±.5 ±. ±. na A VOL Large Signal Voltage Gain R L 2kΩ, V O = ±V V/mV CMRR Common Mode Rejection Ratio V CM = ±V db PSRR Power Supply Rejection Ratio V S = ±V to ±8V db Input Voltage Range ± ± ± ± V V OUT Output Voltage Swing R L 2kΩ ±2.5 ±.8 ±2.5 ±.8 V P d Power Dissipation No Load mw per amplifier U W ATCHI G CHARACTERISTICS,, unless otherwise noted. LT2AM/AC LT2M/C SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS I B Input Offset Voltage Match µv Average Non-Inverting Bias Current ±. ±.5 ±.7 ±.8 na I OS Non-Inverting Offset Current na I OS Inverting Offset Current na CMRR Common Mode Rejection Ratio Match V CM = ±V db PSRR Power Supply Rejection Ratio Match V S = ±V to ±8V db Channel Seperation f Hz (Note 5) 2 8 db 2fb

4 LT2 U W ATCHI G CHARACTERISTICS The denotes the specifications which apply over the temperature range 55 C T A 25 C,, unless otherwise noted. LT2AM LT2M SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS I B Input Offset Voltage Match 5 2 µv Input Offset Voltage Tracking....5 µv/ C Average Non-Inverting Bias Current ±.5 ±. ±.8 ±. na I OS Non-Inverting Offset Current na I OS Inverting Offset Current na CMRR Common Mode Rejection Ratio Match V CM = ±V db PSRR Power Supply Rejection Ratio Match V S = ±V to ±8V db The denotes the specifications which apply over the temperature range C T A 7 C,, unless otherwise noted. LT2AC LT2C SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS I B Input Offset Voltage Match µv Input Offset Voltage Tracking....5 µv/ C Average Non-Inverting Bias Current ±. ±.5 ±.2 ±7. na I OS Non-Inverting Offset Current na I OS Inverting Offset Current na CMRR Common Mode Rejection Ratio Match V CM = ±V db PSRR Power Supply Rejection Ratio Match V S = ±V to ±8V db For MIL-STD components, please refer to LTC 88C data sheet for test listing and parameters. Note : Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: Offset voltage measured with high speed test equipment, approximately second after power is applied. Note : This parameter is tested on a sample basis only. Note : Long Term Input Offset Voltage Stability refers to the averaged trend line of V OS versus Time over extended periods after the first days of operation. Excluding the initial hour of operation, changes in V OS during the first operating days are typically 2.5µV. Note 5: Parameter is guaranteed by design. Note : Hz noise voltage density is sample tested on every lot. Devices tested at Hz are available on request. Note 7: The V supply terminals are completely independent and may be powered by separate supplies if desired (this approach, however, would sacrifice the advantages of the power supply rejection ratio matching). The V supply terminals are both connected to the common substrate and must be tied to the same voltage. Both V pins should be used. 2fb

5 TYPICAL PERFORMANCE CHARACTERISTICS NUMBER OF UNITS 8 2 U W Distribution of Offset Voltage of Individual Amplifiers 57 UNITS TESTED NUMBER OF UNITS Distribution of Offset Voltage Drift with Temperature (Individual Amplifiers) 2 UNITS TESTED NUMBER OF UNITS LT2 Distribution of Offset Voltage Match Drift with Temperature UNITS TESTED INDIVIDUAL AMPLIFIER OFFSET VOLTAGE (µv) INPUT OFFSET VOLTAGE (µv) Offset Voltage Drift with Temperature of Six Representative Units LT2AM LT2M LT2AM LT2M LT2AM LT2M 2 G TEMPERATURE ( C) 2 G OFFSET VOLTAGE MATCH (µv) INPUT OFFSET VOLTAGE DRIFT WITH TEMPERATURE (µv/ C) G2 Offset Voltage Tracking with Temperature of Six Representative Units LT2AM LT2M LT2M LT2M LT2AM LT2AM TEMPERATURE ( C) 2 G CHANGE IN OFFSET VOLTAGE (MICROVOLTS) OFFSET VOLTAGE MATCH DRIFT WITH TEMPERATURE (µv/ C) 5 2 Warm-Up Drift N PLASTIC PACKGE 2 G J HERMETIC DIP PACKGE 2 5 TIME AFTER POWER ON BOTH AMPLIFIERS (MINUTES) 2 G OFFSET VOLTAGE CHANGE (µv) 5 5 Long Term Stability of Four Representative Units NOISE VOLTAGE nv/div.hz to Hz Noise VOLTAGE NOISE nv/ Hz Noise Spectrum V S = ± TO ±8V /f CORNER Hz VOLTAGE /f CORNER 7Hz. CURRENT NOISE pa/ Hz CURRENT 2 5 TIME (MONTHS) 2 8 TIME (SECONDS). FREQUENCY (Hz) G7 G8 2 G9 2fb 5

6 LT2 TYPICAL PERFORMANCE CHARACTERISTICS U W INPUT BIAS AND OFFSET CURRENTS (na) Matching and Individual Amplifier Bias and Offset Currents vs Temperature MATCHING: NON INVERTING BIAS CURRENT MATCHING: NON-INV. OFFSET CURRENT INDIVIDUAL AMP BIAS CURRENT INVERING & INDIVIDUAL AMP OFFSET CURRENT TEMPERATURE ( C) G INPUT BIAS CURRENT (na) Input Bias Current Over the Common Mode Range V CM DEVICE WITH POSITIVE INPUT CURRENT DEVICE WITH NEGATIVE INPUT CURRENT COMMON-MODE INPUT RESISTANCE = 28V = 28GΩ.nA COMMON-MODE INPUT VOLTAGE I b 2 G INVERTING OR NON-INVERTING INPUT BIAS CURRENT (ma) 2. Input Bias Current vs. Differential Input Voltage I B na... ±DIFFERENTIAL INPUT (VOLTS) 2 G2 Open Loop Voltage Gain vs Temperature Open Loop Voltage Gain Frequency Response 2 Gain, Phase Shift vs. Frequency 8 OPEN LOOP VOLTAGE GAIN (V/V) 2k k 8k k k 2k 5, V O = ±2V V S = ±V, V O = ±V TEMPERATURE ( C) OPEN LOOP VOLTAGE GAIN (db) V S = ±V k k k M FREQUENCY (Hz) M VOLTAGE GAIN (db) 2 PHASE 25 C 8 25 C PHASE MARGIN GAIN 25 C = GAIN 25 C & 55 C PHASE MARGIN 55 C = 8 25 C = FREQUENCY (MHz) PHASE SHIFT (DEGREES) 2 G 2 G 2 G5 OPEN LOOP GAIN MISMATCH (PERCENT) Open Loop Gain Mismatch vs Frequency PERCENT GAIN MISMATCH = OUTPUT A OUTPUT B / 2(OUTPUT A OUTPUT B) OUTPUT IMPEDANCE (Ω).. Closed Loop Output Impedance A V = A V = I O = ±ma POWER SUPPLY REJECTION (db) Power Supply Rejection and PSRR Match vs Frequency NEGATIVE SUPPLY ±2V pp MATCH (NEGATIVE SUPPLY) POSITIVE SUPPLY MATCH (POSITIVE SUPPLY) k k k FREQUENCY (Hz). k k k FREQUENCY (Hz). k k k FREQUENCY (Hz) 2 G 2 G7 2 G8 2fb

7 LT2 TYPICAL PERFORMANCE CHARACTERISTICS U W CHANNEL SEPARATION (db) Channel Separation vs Frequency R S =Ω R S =k k k k FREQUENCY (Hz) R S =Ω 2 G9 M COMMON MODE REJECTION (db) Common Mode Rejection and CMRR Match vs Frequency CMRR MATCH ( CMRR) k k k M FREQUENCY (Hz) < 2 G2 COMMON MODE LIMIT (VOLTS) REFERRED TO POWER SUPPLY V Common Mode Limit vs Temperature V =.2 to V V = 2 to 8V V = 2 to 8V.8.. V =.2 to V V TEMPERATURE ( C) 2 G2 SUPPLY CURRENT (ma) Supply Current vs. Supply Voltage For Each Amplifier 55 C 25 C 25 C ± ± ±9 ±2 ±5 ±8 ±2 SUPPLY VOLTAGE (V) Large Signal Transient Response 2 G2 OUTPUT VOLTAGE, PEAK-TO-PEAK (VOLTS) Maximum Undistorted Output vs. Frequency FREQUENCY (khz) 2 G22 2 G2 Small Signal Transient Response PERCENT OVERSHOOT 8 Voltage Follower Overshoot vs Capacitive Load V IN = mv R L > 5k Small Signal Transient Response 2 A V =, C L = 5pF 2 G25,, CAPACITIVE LOAD (PICOFARADS) A V =, C L = pf 2 G27 2 G2 2fb 7

8 LT2 TYPICAL PERFORMANCE CHARACTERISTICS U W Output Swing vs. Load Resistance 5 Output Short Circuit Current vs Time OUTPUT SWING (VOLTS) 2 8 NEGATIVE SWING POSITIVE SWING k k LOAD RESISTANCE (Ω) SHORT CIRCUIT CURRENT (ma) SINKING SOURCING C 25 C 25 C 25 C 25 C 55 C 2 TIME FROM OUTPUT SHORT (MINUTES) 2 G28 2 G29 APPLICATIONS INFORMATION U W U U The LT2 dual amplifier may be inserted directly into OP-, OP27, OP227 sockets with or without removal of external nulling potentiometers. Offset Voltage Adjustment The input offset voltage of the LT2, and its drift with temperature, are permanently trimmed at wafer testing to a low level. However, if further adjustment of V OS is necessary, nulling with a k or 2k potentiometer will not degrade drift with temperature. Trimming to a value other than zero creates a drift of (V OS / )µv/ C, e.g. if V OS is adjusted to µv, the change in drift will be µv/ C. The adjustment range with a k or 2k pot is approximately ±2.5mV. If less adjustment range is needed, the sensitivity and resolution of the nulling can be improved by using a smaller pot in conjunction with fixed resistors. The example has an approximate null range of ±µv. nately, the guaranteed offset voltage match of the LT2 is very low, in most applications offset adjustment will be unnecessary. () INPUT () Standard Adjustment k or 2k (8) 2 (9) LT2 2 (5) (7) () OUTPUT 2 TA Improved Sensitivity Adjustment 7.5k k In matching applications, both amplifiers can be trimmed to zero, or the offset of one amplifier can be trimmed to match the offset of the other. Offset adjustment, however, slightly degrades the gain, common-mode and powersupply rejection match between the two op amps. Fortu- 7.5k (8) 2 (9) () (7) INPUT LT2 () () 2 (5) OUTPUT 2 TA 8 2fb

9 LT2 APPLICATIONS INFORMATION Test Circuit for Offset Voltage and its Drift with Temperature U W U U.µF.Hz to Hz Noise Test Circuit 5k* k VOLTAGE GAIN = 5, Ω* 5k* () () LT2 (7) 2 (5) V O = V OS () V O * RESISTORS MUST HAVE LOW THERMOELECTRIC POTENTIAL. 2 TA5 Ω A LT2 DEVICE UNDER TEST 2k.7µF PEAK TO PEAK NOISE MEASURED IN SEC INTERVAL B LT2 2.k k.µf.k 2.2µF 22µF SCOPE R IN = MΩ k 2 TA This circuit is also used as burn-in configuration for the LT2, with supply voltages increased to ±2V. Unless proper care is exercised, thermocouple effects, caused by temperature gradients across dissimilar metals at the contacts to the input terminals, can exceed the inherent drift of the amplifier. Air currents should be minimized, package leads should be short, the two input leads should be as close together as possible and maintained at the same temperature. Channel Separation This parameter is defined as the ratio of the change in input offset voltage of one amplifier to the change in output voltage of the other amplifier causing the offset change. At low frequencies the LT2 s channel separation is an almost unmeasurable 8dB. As frequency increases, pin to pin capacitance of the package, between the output of one amplifier and the inputs of the other, becomes dominant. Since these pins are non-adjacent, the capacitance is only.2pf. To maintain the LT2 s excellent channel separation at higher frequencies, the socket and PC board capacitances should be minimized. The device under test should be warmed up for three minutes and shielded from air currents. Turn the device 8 to measure the noise of side B. Power supplies The LT2 is specified over a wide range of power supply voltages from ±V to ±8V. Operation with lower supplies is possible, down to ±.2V (two Ni-Cad batteries). However, with ±.2V supplies, the device is stable only in closed loop gains of 2 or higher (or inverting gain of one or higher). The V supply terminals are completely independent and may be powered by separate supplies if desired (this approach, however, would sacrifice the advantages of the power supply rejection ratio matching). The V supply terminals are both connected to the common substrate and must be tied to the same voltage. Both V pins should be used. 2fb 9

10 LT2 APPLICATIONS INFORMATION U W U U Advantages of Matched Dual Op Amps In many applications the performance of a system depends on the matching between two operational amplifiers rather than the individual characteristics of the two op amps. Two or three op amp instrumentation amplifiers, tracking voltage references and low drift active filters are some of the circuits requiring matching between two op amps. The well-known triple op amp configuration illustrates these concepts. Output offset is a function of the difference between the offsets of the two halves of the LT2. This error cancellation principle holds for a considerable number of input referred parameters in addition to offset voltage and its drift with temperature. Input bias current will be the average of the two non-inverting input currents (I B ). The difference between these two currents (I OS ) is the offset current of the instrumentation amplifier. The difference between the inverting input currents (I OS ) will cause errors flowing through R, R2, and R. Commonmode and power supply rejections will be dependent only on the match between the two amplifiers (assuming perfect resistor matching). INPUT INPUT A LT2 B LT2 Three Op Amp Instrumentation Amplifier R k R 2.k R8 2Ω R2 k R Ω R5 Ω R k C pf R7 9.7k R9 2Ω R k LT7 GAIN = Trim R8 for gain Trim R9 for DC common mode rejection Trim R for AC common mode rejection OUTPUT 2 TA7 The concepts of common mode and power supply rejection ratio match ( CMRR and PSRR) are best demonstrated with a numerical example: Assume CMRR A =.µv/v or 2dB, and CMRR B =.75µV/V or 22.5dB, then CMRR =.25µV/V or 2dB; if CMRR B =.75µV/V which is still 22.5dB, then CMRR =.75µV/V or 5dB. Typical performance of the instrumentation amplifier: Input offset voltage = 25µV Input bias current =.7nA Input resistance = 2 GΩ Input offset current =.na Input noise =.5µV p-p Power bandwidth (V = ±V) = 8kHz Clearly, the LT2, by specifying and guaranteeing all of these matching parameters, can significantly improve the performance of matching dependent circuits. 2fb

11 LT2 APPLICATIONS INFORMATION U W U U Precision ±V Reference k 5%.k k OUT.V LM29A. k. 7 LT2 2 LT2.k 5 OUT 2.V 8.2k k 2 TA8 The LT2 contributes less than 5% of the total drift with temperature, noise and long term drift of the reference. The accuracy of the V output is limited by the matching of the two k resistors. Dual Limit Microvolt Comparator k 9.2Ω k 5% FLV7 UPPER LIMIT LT2 2 5k 2k 5% / CA8 / CA8 INPUT k 9.2Ω LOWER LIMIT 7 LT k / CA8 / CA8 2 TA9 When the upper or lower limit is exceeded the LED lights up. Positive feedback to one of the nulling terminals creates 5 to 2µV of hysteresis on both amplifiers. This feedback changes the offset voltage of the LT2 by less than 5µV. Therefore, the basic accuracy of the comparator is limited only by the low offset voltage of the LT2. 2fb

12 LT2 APPLICATIONS INFORMATION U W U U Two Op Amp Instrumentation Amplifier R5 2.2k R k* R2 k R k INPUTS R k LT2 OUTPUT LT2 2 TA * TRIM FOR COMMON-MODE REJECTION TRIM FOR GAIN R R2 R R2 R GAIN = R R R R5 2 ( ) Precision Amplifier Drives 5Ω Load to ±V.R f.r S k R S Ω B LT2 R f k.2r L Ω R S Ω INPUT A LT2 R L 5Ω OUTPUT 2 TA This application utilizes the guaranteed ma load driving capability of the LT2. The offset voltage of amplifier A is the offset of the configuration. Amplifier B provides the additional ma load current. When load resistor R L is 2 removed, amplifier A sinks this current without affecting accuracy. In the gain of configuration shown, approximately.% gain accuracy can be realized. 2fb

13 LT2 APPLICATIONS INFORMATION U W U U Dead Zone Generator INPUT k** k Q 2N9 k 2 2 k** k* LMA pf LMA IN9 5pF 8 Q Q2.7k.7k k*.7k.k Q5 k Q V SET DEAD ZONE CONTROL INPUT to 5V LT2 2k 5pF IN9 * FILM ** RATIO MATCH.5% Q2,,, 5 CA 9 TRANSISTOR ARRAY BIPOLAR SYMMETRY IS EXCELLENT BECAUSE ONE DEVICE, Q2, SETS BOTH LIMITS k** k k V SET Q 2N9 7pF k** LT2 V OUT V SET V IN V OUT 2 TA2 Precision Absolute Value Circuit k. k. k. INPUT to V k. LT2 k. IN8 IN8 LT2 OUTPUT to V 2 TA 2fb

14 LT2 APPLICATIONS INFORMATION U W U U Ω k* (SELECT) 22k* LT2 2k IN9 Ω 5W 2N229 Dual Precision Power Supply () to V in µv Steps (2) to V in mv Steps OUTPUT -V 25mA 8.2k VN- TRIAD TY-9 LM99 KVD = ESI#DP * = JULIE RSCH. LABS #R- 8pF 2 25k LTA KVD KELVIN-VARLEY DIVIDER ESI#DP k D CLK 7C7 VN- Q Q.µF DIODES = SEMTECH # FF-5 2.2µF 2N5 2k IN9 9k* OUTPUT 2 V-V, 25mA k* (SELECT) TRIMV Ω LT2 k k 22µF 5Ω.8k CLAMP SET 5k IN9 2N297 2 TA 2fb

15 SCHE ATIC DIAGRA W W LT2 V k k NULL k NULL k Q27 Q28 Q29 Q2.5k Q25 Q Q2 25k Q5 Q Q Q Q7 Q Q Q8 55pF k 2pF Q Q 5 QA QB Q2B Q2A pf k Q2 2 OUT IN Q2 2 IN 5 Q T Q5 2k Q 2k Q22 Q Q2 Q2 LT2 Q9 8Ω Q2 Q7 Q8 Q V Q9 8k SS PACKAGE DESCRIPTION U J Package -Lead CERDIP (Narrow. Inch, Hermetic) (Reference LTC DWG # 5-8-). BSC (.72 BSC).2 (5.8) MAX.5 (.27) MIN.785 (9.99) MAX (.2.57) 5.5. (.8.52).25 (.5) RAD TYP ( ).5.5 (..5) NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS..2 (..). (2.5) BSC.25 (.75) MIN J 298 OBSOLETE PACKAGE 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. 2fb 5

16 LT2 PACKAGE DESCRIPTION U N Package -Lead PDIP (Narrow. Inch) (Reference LTC DWG # 5-8-5).77* (9.558) MAX ±.5* (.77 ±.8) ( ). ±.5 (.2 ±.27).5.5 (..5).9.5 (.229.8) ( ).2 (.58) MIN.25 (.75) MIN.5 (.25) MIN *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED. INCH (.25mm). (2.5) BSC.5 (.5) TYP.8 ±. (.57 ±.7) N 98 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT Single LT2 µv V OS, µv/ C Precision Op Amp LT88/LT885 Dual/Quad Precision Op Amp with Rail-to-Rail Output 5µV Max V OS, pa Max I B Linear Technology Corporation McCarthy Blvd., Milpitas, CA (8) 2-9 FAX: (8) fb LT/CPI.5K REV B PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 985

FEATURES DESCRIPTION APPLICATIONS Strain Gauge Signal Conditioner with Bridge Excitation Distribution of Offset Voltage Match

FEATURES DESCRIPTION APPLICATIONS Strain Gauge Signal Conditioner with Bridge Excitation Distribution of Offset Voltage Match LT2 Dual, Matched Precision Operational Amplifier FEATURES Guaranteed low offset voltage LT2A µv max LT2 µv max Guaranteed offset voltage match LT2A µv max LT2 8µV max Guaranteed low drift LT2A.9µV/ C