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INA118 Precision, Low-Power Instrumentation Amplifier Datasheet

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INA118 Precision, Low-Power Instrumentation Amplifier Datasheet Product Order Technical Tools & Support & Folder Now Documents Software Community INA118 SBOS027B –SEPTEMBER 2000–REVISED APRIL 2019 INA118 Precision, Low-Power Instrumentation Amplifier A newer version of this device is now available: INA818 1 Features 3 Description The INA118 is a low-power, general-purpose 1• A newer version of this device is now available: INA818 instrumentation amplifier offering excellent accuracy. The versatile, three op amp design and small size • Low offset voltage: 50 µV, maximum make this device an excellent choice for a wide range • Low drift: 0.5 µV/°C, maximum of applications. Current-feedback input circuitry • Low input bias current: 5 nA, maximum provides wide bandwidth, even at high gain (70 kHz at G = 100). • High CMR: 110 dB, minimum • Inputs protected to ±40 V A single external resistor sets any gain from 1 to 10000. Internal input protection can withstand up to • Wide supply range: ±1.35 to ±18 V ±40 V without damage. • Low quiescent current: 350 µA The INA118 is laser-trimmed for low offset voltage • Packages: 8-Pin plastic DIP, SO-8 (50 µV), drift (0.5 µV/°C), and high common-mode rejection (110 dB at G = 1000). The INA118 operates 2 Applications with power supplies as low as ±1.35 V, and quiescent • Bridge amplifiers current is only 350 µA, making this device an excellent choice for battery-operated systems. • Thermocouple amplifiers • RTD Sensor amplifiers The INA118 is available in 8-pin plastic DIP and SO-8 surface-mount packages, and specified for the –40°C • Medical instrumentation to +85°C temperature range. • Data acquisition The upgraded INA818 offers a lower input stage offset voltage (35 µV, maximum), lower input bias current (0.5 nA maximum) and lower noise (8 nV/√Hz) at the same quiescent current. See the Device Comparison Table for a selection of precision instrumentation amplifiers from Texas Instruments. Device Information(1) PART NUMBER PACKAGE BODY SIZE (NOM) SOIC (8) 3.91 mm × 4.90 mm INA118 PDIP (8) 6.35 mm × 9.81 mm (1) For all available packages, see the package option addendum at the end of the data sheet. Simplified Schematic V+ 7 – 2 Over-Voltage INA118 V IN Protection A1 50kΩ G = 1 + 60kΩ 60kΩ RG 1 25kΩ A 6 RG 3 VO 8 25kΩ 5 A2 Ref + 3 Over-Voltage 60kΩ 60kΩ VIN Protection 4 V– 1 An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications, intellectual property matters and other important disclaimers. PRODUCTION DATA. A newer version of this device is now available: INA818 INA118 SBOS027B –SEPTEMBER 2000–REVISED APRIL 2019 www.ti.com Table of Contents 1 Features .................................................................. 1 9 Application and Implementation ........................ 14 2 Applications ........................................................... 1 9.1 Application Information............................................ 14 3 Description ............................................................. 1 9.2 Typical Application ................................................. 14 4 Revision History..................................................... 2 10 Power Supply Recommendations ..................... 18 5 Device Comparison Table..................................... 3 10.1 Low-Voltage Operation ......................................... 18 6 Pin Configuration and Functions ......................... 4 10.2 Single-Supply Operation ....................................... 19 7 Specifications......................................................... 5 11 Layout................................................................... 20 7.1 Absolute Maximum Ratings ...................................... 5 11.1 Layout Guidelines ................................................. 20 7.2 ESD Ratings ............................................................ 5 11.2 Layout Example .................................................... 21 7.3 Recommended Operating Conditions....................... 5 12 Device and Documentation Support ................. 22 7.4 Thermal Information.................................................. 5 12.1 Device Support .................................................... 22 7.5 Electrical Characteristics........................................... 6 12.2 Documentation Support ........................................ 22 7.6 Typical Characteristics.............................................. 8 12.3 Community Resources.......................................... 22 8 Detailed Description ............................................ 12 12.4 Trademarks ........................................................... 22 8.1 Overview ................................................................. 12 12.5 Electrostatic Discharge Caution............................ 22 8.2 Functional Block Diagram ....................................... 12 12.6 Glossary ................................................................ 22 8.3 Feature Description................................................. 13 13 Mechanical, Packaging, and Orderable 8.4 Device Functional Modes........................................ 13 Information ........................................................... 22 4 Revision History NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Changes from Revision A (January 2016) to Revision B Page • Added information about the newer, upgraded INA818 ........................................................................................................ 1 • Added Device Comparison Table........................................................................................................................................... 3 Changes from Original (September 2000) to Revision A Page • Added ESD Ratings table, Feature Description section, Device Functional Modes section, Application and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information section. .............................................................. 1 2 Submit Documentation Feedback Copyright © 2000–2019, Texas Instruments Incorporated Product Folder Links: INA118 A newer version of this device is now available: INA818 INA118 www.ti.com SBOS027B –SEPTEMBER 2000–REVISED APRIL 2019 5 Device Comparison Table DEVICE DESCRIPTION GAIN EQUATION RG PINS AT PIN 35-µV Offset, 0.4 µV/°C V Drift, 8-nV/√Hz Noise, Low-Power, INA818 OS G = 1 + 50 kΩ / RG 1, 8 Precision Instrumentation Amplifier 35-µV Offset, 0.4 µV/°C V Drift, 8-nV/√Hz Noise, Low-Power, INA819 OS G = 1 + 50 kΩ / RG 2, 3 Precision Instrumentation Amplifier 35-µV Offset, 0.4 µV/°C V Drift, 7-nV/√Hz Noise, High- INA821 OS G = 1 + 49.4 kΩ / RG 2, 3 Bandwidth, Precision Instrumentation Amplifier 50-µV Offset, 0.5 µV/°C V Drift, 7-nV/√Hz Noise, Low-Power, INA828 OS G = 1 + 50 kΩ / RG 1, 8 Precision Instrumentation Amplifier 25-µV V , 0.1 µV/°C V Drift, 1.8-V to 5-V, RRO, 50-µA I , INA333 OS OS Q G = 1 + 100 kΩ / RG 1, 8 chopper-stabilized INA 20-mV to ±10-V Programmable Gain IA With 3-V or 5-V PGA280 Digital programmable N/A Differential Output; Analog Supply up to ±18 V G = 0.2 V Differential Amplifier for ±10-V to 3-V and 5-V INA159 G = 0.2 V/V N/A Conversion PGA112 Precision Programmable Gain Op Amp With SPI Digital programmable N/A Copyright © 2000–2019, Texas Instruments Incorporated Submit Documentation Feedback 3 Product Folder Links: INA118 A newer version of this device is now available: INA818 INA118 SBOS027B –SEPTEMBER 2000–REVISED APRIL 2019 www.ti.com 6 Pin Configuration and Functions P and D Packages 8-Pin PDIP and SOIC Top View RG 1 8 RG – V IN 2 7 V+ + V IN 3 6 VO V– 4 5 Ref Pin Functions PIN I/O DESCRIPTION NO. NAME 1 RG — Gain setting pin. For gains greater than 1, place a gain resistor between pin 1 and pin 8. – 2 V IN I Negative input + 3 V IN I Positive input 4 V– — Negative supply 5 Ref I Reference input. This pin must be driven by low impedance or connected to ground. 6 VO O Output 7 V+ — Positive supply 8 RG — Gain setting pin. For gains greater than 1, place a gain resistor between pin 1 and pin 8. 4 Submit Documentation Feedback Copyright © 2000–2019, Texas Instruments Incorporated Product Folder Links: INA118 A newer version of this device is now available: INA818 INA118 www.ti.com SBOS027B –SEPTEMBER 2000–REVISED APRIL 2019 7 Specifications 7.1 Absolute Maximum Ratings over operating free-air temperature range (unless otherwise noted)(1) MIN MAX UNIT Supply voltage ±18 V Analog input voltage ±40 V Output short-circuit (to ground) Continuous Operating temperature –40 125 °C Junction temperature 150 °C Lead temperature (soldering, 10 s) 300 °C Tstg Storage temperature –40 125 °C (1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. 7.2 ESD Ratings VALUE UNIT Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1) ±1000 V(ESD) Electrostatic discharge Charged-device model (CDM), per JEDEC specification JESD22- V ±500 C101(2) (1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process. (2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process. 7.3 Recommended Operating
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