High Accuracy INSTRUMENTATION AMPLIFIER

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1 INA High Accuracy INSTRUMENTATION AMPLIFIER FEATURES LOW DRIFT:.µV/ C max LOW OFFSET VOLTAGE: µv max LOW NONLINEARITY:.% LOW NOISE: nv/ Hz HIGH CMR: db AT Hz HIGH INPUT IMPEDANCE: Ω -PIN PLASTIC, CERAMIC DIP, SOL-, AND TO- PACKAGES APPLICATIONS STRAIN GAGES THERMOCOUPLES RTDs REMOTE TRANSDUCERS LOW-LEVEL SIGNALS MEDICAL INSTRUMENTATION DESCRIPTION The INA is a high accuracy instrumentation amplifier designed for low-level signal amplification and general purpose data acquisition. Three precision op amps and laser-trimmed metal film resistors are integrated on a single monolithic integrated circuit. The INA is packaged in TO- metal, -pin plastic and ceramic DIP, and SOL- surface-mount packages. Commercial, industrial and military temperature range models are available. Adj. TO- PACKAGE Adj. A DIP PACKAGE kω A kω INA Gain Sense Gain Set kω A kω INA kω kω A Gain Set Gain Sense kω kω A A A A International Airport Industrial Park Mailing Address: PO Box, Tucson, AZ Street Address: S. Tucson Blvd., Tucson, AZ Tel: () - Twx: -- Internet: FAXLine: () - (US/Canada Only) Cable: BBRCORP Telex: - FAX: () - Immediate Product Info: () - SBOS Burr-Brown Corporation PDS-K Printed in U.S.A. July,

2 SPECIFICATIONS ELECTRICAL At + C with ±VDC power supply and in circuit of Figure, unless otherwise noted. INAAM, AG INASM, SG INACM, CG INAHP, KU PARAMETER MIN TYP MAX MIN TYP MAX MIN TYP MAX MIN TYP MAX UNITS GAIN Range of Gain * * * * * * V/V Gain Equation G = + (k/ ) * * * V/V Error from Equation, DC () ±(. +.G ±(. +.G * * * * ±(. + ±(. + %./G)./G).G).G)./G./G Gain Temp. Coefficient () G = * * * * * * ppm/ C G = * * * * * ppm/ C G = * * * * * ppm/ C G = * * * * * ppm/ C Nonlinearity, DC () ±(. + G) ±(. + x G) ±(. ±(. ±(. ±(. * * % of p-p FS + G) + G) + G) + G) RATED OUTPUT Voltage ± ±. * * * * * * V Current ± ± * * * * * * ma Impedance. * * * Ω Capacitive Load * * * pf INPUT OFFSET VOLTAGE Initial at + C ±( + /G) ±( + /G) ±+ ±( ±(+ ±( + ±( + ±( + µv /G) +/G) /G) /G) /G) /G) vs Temperature ±( + /G) ±(. ±(. + ±( + /G) µv/ C + /G) /G) vs Supply ±( + /G) * * * µv/v vs Time ±( + /G) * * * µv/mo INPUT BIAS CURRENT Initial Bias Current (each input) ± ± ± * ± ± * * na vs Temperature ±. * * * na/ C vs Supply ±. * * * na/v Initial Current ± ± ± * ± ± * * na vs Temperature ±. * * * na/ C INPUT IMPEDANCE Differential * * * Ω pf -mode * * * Ω pf INPUT VOLTAGE RANGE Range, Linear Response ± ± * * * * * * V CMR with kω Source Imbalance DC to Hz, G = * * * * db DC to Hz, G = * * * * db DC to Hz, G = to * * * * db INPUT NOISE Input Voltage Noise f B =.Hz to Hz. * * * µv, p-p Density, G = f O = Hz * * * nv/ Hz f O = Hz * * * nv/ Hz f O = khz * * * nv/ Hz Input Current Noise f B =.Hz to Hz * * * pa, p-p Density f O = Hz. * * * pa/ Hz f O = Hz. * * * pa/ Hz f O = khz. * * * pa/ Hz DYNAMIC RESPONSE Small Signal, ±db Flatness G = * * * khz G = * * * khz G = * * * khz G =. * * * khz Small Signal, ±% Flatness G = * * * khz G = * * * khz G = * * * khz G = * * * Hz Full Power, G = to. * * * khz Slew Rate, G = to.. * * * * * * V/µs Settling Time (.%) G = * * * * * * µs G = * * * * * * µs G = * * * * * * µs Settling Time (.%) G = * * * * * * µs G = * * * * * * µs G = * * * * * * µs POWEUPPLY Rated Voltage ± * * * V Voltage Range ± ± * * * * * * V Current, Quiescent () ±. ±. * * * * * * ma TEMPERATURE RANGE () Specification + + * * + C Operation + * * * * + C Storage + * * * * + C * Specifications same as for INAAM, AG. NOTES: () Typically the tolerance of will be the major source of gain error. () Nonlinearity is the maximum peak deviation from the best straight-line as a percentage of peak-to-peak full scale output. () Not including the TCR of. () Adjustable to zero at any one gain. () θ JC output stage = C/W, θ JC quiescent circuitry = C/W, θ CA = C/W. INA

3 PIN CONFIGURATIONS Top View Gain Set TO- M Package In DIP G and P Package Adjust Adjust Gain Set +In VCC SOIC U Package Gain Sense Gain Set Adj. Adj. Gain Sense Gain Set A A Gain Sense Gain Sense Gain Set Gain Set Adj. A Adj. A NC NC ORDERING INFORMATION PRODUCT PACKAGE TEMPERATURE RANGE INAAM -Pin Metal TO- C to + C INACM -Pin Metal TO- C to + C INAAG -Pin Ceramic DIP C to + C INACG -Pin Ceramic DIP C to + C INAHP -Pin Plastic DIP C to + C INAKU SOL- Surface-Mount C to + C INASG -Pin Ceramic DIP C to + C INASM -Pin Metal TO- C to + C ABSOLUTE MAXIMUM RATINGS Supply Voltage... ±V Power Dissipation... mw Input Voltage Range... ±V CC Short Circuit (to ground)... Continuous Operating Temperature M, G Package... C to + C P, U Package... C to + C Storage Temperature M, G Package... C to + C P, U Package... C to + C Lead Temperature (soldering, s) M, G, P Package... + C Lead Temperature (wave soldering, s) U Package... + C PACKAGE INFORMATION PACKAGE DRAWING PRODUCT PACKAGE NUMBER () INAAM -Pin Metal TO- INACM -Pin Metal TO- INAAG -Pin Ceramic DIP INACG -Pin Ceramic DIP INAHP -Pin Plastic DIP INAKU SOL- Surface-Mount INASG -Pin Ceramic DIP INASM -Pin Metal TO- NOTE: () For detailed drawing and dimension table, please see end of data sheet, or Appendix D of Burr-Brown IC Data Book. ELECTROSTATIC DISCHARGE SENSITIVITY This integrated circuit can be damaged by ESD. Burr-Brown recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications. The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes no responsibility for the use of this information, and all use of such information shall be entirely at the user s own risk. Prices and specifications are subject to change without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant any BURR-BROWN product for use in life support devices and/or systems. INA

4 TYPICAL PERFORMANCE CURVES At + C, V CC = ±V unless otherwise noted.. GAIN NONLINEARITY vs GAIN GAIN vs FREQUENCY Gain Nonlinearity (% p-p, FS).. Max Typ Gain (db) G = G = G = G = % Error. Gain (V/V) k k k M Frequency (Hz) CMR (db) G =, G = G = Balanced Source CMR vs FREQUENCY Change in Input Voltage (µv) WARM-UP DRIFT vs TIME k k Frequency (Hz) Time (Minutes) ± QUIESCENT CURRENT vs SUPPLY STEP RESPONSE Quiescent Current (ma) ± ± ± (V) + + G = G = ± ± ± ± ± Supply Voltage (V) Time (µs) INA

5 TYPICAL PERFORMANCE CURVES (CONT) At + C, V CC = ±V unless otherwise noted. SETTLING TIME vs GAIN OUTPUT NOISE vs GAIN Settling Time (µs) R L = kω C L = pf.%.% % Noise Voltage (mv, rms) = = MΩ = kω = Gain (V/V) Gain (V/V) INPUT NOISE VOLTAGE vs FREQUENCY ( GAIN ) Input Noise Voltage (nv/ Hz) Frequency (Hz) APPLICATION INFORMATION Figure shows the basic connections required for operation of the INA. (Pin numbers shown are for the TO- metal package.) Applications with noisy or high impedance power supplies may require decoupling capacitors close to the device pins as shown. The output is referred to the output terminal which is normally grounded. This must be a low-impedance connection to assure good common-mode rejection. A resistance greater than.ω in series with the pin will cause common-mode rejection to fall below db. SETTING THE GAIN Gain of the INA is set by connecting a single external resistor, : G = + kω () The kω term in equation () comes from the sum of the two internal feedback resistors. These are on-chip metal film resistors which are laser trimmed to accurate absolute values. The accuracy and temperature coefficient of these resistors are included in the gain accuracy and drift specifications of the INA. The stability and temperature drift of the external gain setting resistor,, also affects gain. s contribution to gain accuracy and drift can be directly inferred from the gain equation (). Low resistor values required for high gain can make wiring resistance important. Sockets add to the wiring resistance which will contribute additional gain error (possibly an unstable gain error) in gains of approximately or greater. The gain sense connections on the DIP and SOL- packages (see Figure ) reduce the gain error produced by wiring or socket resistance. INA

6 OFFSET TRIMMING The INA is laser trimmed for low offset voltage and drift. Most applications require no external offset adjustment. Figure shows connection of an optional potentiometer connected to the Adjust pins for trimming the input offset voltage. (Pin numbers shown are for the DIP package.) Use this adjustment to null the offset voltage in high gain (G ) with both inputs connected to ground. Do not use this adjustment to null offset produced by the source or other system offset since this will increase the offset voltage drift by.µv/ C per µv of adjusted offset. of the output amplifier usually dominates when the INA is used in unity gain (G = ). The output offset voltage can be adjusted with the optional trim circuit connected to the pin as shown in Figure. The voltage applied to terminal is summed with the output. Low impedance must be maintained at this node to assure good common-mode rejection. The op amp connected as a buffer provides low impedance. THERMAL EFFECTS ON OFFSET VOLTAGE To achieve lowest offset voltage and drift, prevent air currents from circulating near the INA. Rapid changes in temperature will produce a thermocouple effect on the package leads that will degrade offset voltage and drift. A shield or cover that prevents air currents from flowing near the INA will assure best performance. No Connection TO- PACKAGE E INA G = + kω A kω kω A V O = G (E E ) E A Tantalum + µf +V V Tantalum + µf FIGURE. Basic Connections. +V Input Adjustment Do not use to null source or system offset (see text). kω A DIP PACKAGE E INA A kω G = + kω E kω A +V V A A Pinout shown is for DIP packages. +V V V O = G (E E ) +V COM kω MΩ OPA kω V COM Adjustment Approximately ±mv Range FIGURE. Optional Trimming of Input and Voltage. INA

7 IMPORTANT NOTICE Texas Instruments and its subsidiaries (TI) reserve the right to make changes to their products or to discontinue any product or service without notice, and advise customers to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale supplied at the time of order acknowledgment, including those pertaining to warranty, patent infringement, and limitation of liability. TI warrants performance of its semiconductor products to the specifications applicable at the time of sale in accordance with TI s standard warranty. Testing and other quality control techniques are utilized to the extent TI deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily performed, except those mandated by government requirements. Customers are responsible for their applications using TI components. In order to minimize risks associated with the customer s applications, adequate design and operating safeguards must be provided by the customer to minimize inherent or procedural hazards. TI assumes no liability for applications assistance or customer product design. TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other intellectual property right of TI covering or relating to any combination, machine, or process in which such semiconductor products or services might be or are used. TI s publication of information regarding any third party s products or services does not constitute TI s approval, warranty or endorsement thereof. Copyright, Texas Instruments Incorporated

Precision G = 100 INSTRUMENTATION AMPLIFIER

Precision G = 100 INSTRUMENTATION AMPLIFIER Precision G = INSTRUMENTATION AMPLIFIER FEATURES LOW OFFSET VOLTAGE: 5µV max LOW DRIFT:.5µV/ C max LOW INPUT BIAS CURRENT: na max HIGH COMMON-MODE REJECTION: db min INPUT OVERVOLTAGE PROTECTION: ±V WIDE