High Common Mode Voltage Difference Amplifier


Product details


Number of channels (#) 1 Vs (Min) (V) 4 Vs (Max) (V) 36 CMRR (Min) (dB) 90 Common mode input low (Min) (V) -275 Common mode input high (Max) (V) 275 Input offset (+/-) (Max) (uV) 1100 Iq (Typ) (mA) 0.81 Small signal bandwidth (Typ) (MHz) 0.5 Slew rate (Typ) (V/us) 5 Gain (Min) (V/V) 1 Gain (Max) (V/V) 1 Gain error (+/-) (Max) (%) 0.02 Rating Catalog Operating temperature range (C) -40 to 125 Gain drift (Max) (ppm/C) 10 open-in-new Find other Difference amplifiers

Package | Pins | Size

SOIC (D) 8 19 mm² 4.9 x 3.9 open-in-new Find other Difference amplifiers


  • Common-Mode Voltage Range: ±275 V
  • Minimum CMRR: 90 dB from –40°C to +125°C
  • DC Specifications:
    • Maximum Offset Voltage: 1100 µV
    • Maximum Offset Voltage Drift: 15 µV/°C
    • Maximum Gain Error: 0.02%
    • Maximum Gain Error Drift: 10 ppm/°C
    • Maximum Gain Nonlinearity: 0.001% FSR
  • AC Performance:
    • Bandwidth: 500 kHz
    • Typical Slew Rate: 5 V/µs
  • Wide Supply Range: ±2.0 V to ±18 V
    • Maximum Quiescent Current: 900 µA
    • Output Swing on ±15-V Supplies: ±13.5 V
  • Input Protection:
    • Common-Mode: ±500 V
    • Differential: ±500 V
open-in-new Find other Difference amplifiers


The INA149 is a precision unity-gain difference amplifier with a very high input common-mode voltage range. It is a single, monolithic device that consists of a precision op amp and an integrated thin-film resistor network. The INA149 can accurately measure small differential voltages in the presence of common-mode signals up to ±275 V. The INA149 inputs are protected from momentary common-mode or differential overloads of up to 500 V.

In many applications, where galvanic isolation in not required, the INA149 can replace isolation amplifiers. This ability can eliminate costly isolated input side power supplies and the associated ripple, noise, and quiescent current. The excellent 0.0005% nonlinearity and 500-kHz bandwidth of the INA149 are superior to those of conventional isolation amplifiers.

The INA149 is pin-compatible with the INA117 and INA148 type high common-mode voltage amplifiers and offers improved performance over both devices. The INA149 is available in the SOIC-8 package with operation specified over the extended industrial temperature range of –40°C to +125°C.

open-in-new Find other Difference amplifiers

Technical documentation

star = Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 12
Type Title Date
* Data sheet High Common Mode Voltage Difference Amplifier datasheet (Rev. B) Jul. 30, 2012
E-book Tips and tricks for designing with voltage references (Rev. A) May 07, 2021
Application note How to Select Precision Amplifiers for Semiconductor Testers (Rev. A) Dec. 03, 2020
E-book Simplifying Current Sensing (Rev. A) Jan. 09, 2020
Application note High common-mode differential input voltage to ±10-V ADC input circuit Dec. 20, 2018
E-book The Signal e-book: A compendium of blog posts on op amp design topics Mar. 28, 2017
Selection guide TI Components for Aerospace and Defense Guide (Rev. E) Mar. 22, 2017
Technical article Understanding voltage references: level shift of precision voltage references May 15, 2015
More literature A High-Voltage Bidirectional Current Source Dec. 19, 2013
Technical article What you need to know about CMRR- The instrumentation amplifier (part 2) Oct. 29, 2013
Technical article Difference Amplifiers—the need for well-matched resistors Apr. 25, 2012
User guide INA149EVM User's Guide Nov. 15, 2011

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Hardware development

document-generic User guide

The ADS8686S evaluation module (EVM) performance demonstration kit (PDK) is a platform for evaluating the ADS8686S dual simultaneous-sampling analog-to-digital converter (ADC) with an integrated analog front end (AFE).

ADS8686SEVM-PDK includes the ADS8686SEVM board and a precision host interface (PHI (...)

  • Includes hardware and software required for diagnostic testing, as well as accurate performance of ADS8686S ADC
  • PHI controller provides a convenient communication interface to ADS8686SEVM over USB 2.0 (or higher) for power delivery, as well as digital input/output
  • Easy-to-use evaluation software for (...)
document-generic User guide

Speed up your op amp prototyping and testing with the DIP-Adapter-EVM, which provides a fast, easy and inexpensive way to interface with small, surface-mount ICs. You can connect any supported op amp using the included Samtec terminal strips or wire them directly to existing circuits.

The (...)

  • Simplifies prototyping of SMT IC’s
  • Supports 6 common package types
  • Low Cost
document-generic User guide

The INA149EVM is a platform for basic functional evaluation of the INA149 High Common-Mode Difference Amplifier

  • Easy access to pertinent nodes with test points and terminal blocks
  • Convenient input and output filtering
  • Versatile pad for evaluation in current–sensing applications
  • Reverse supply and overvoltage protection
  • Advanced evaluation with prototype areas and SMA/SMB connector footprints
  • Footprints for (...)

Design tools & simulation

SBOM667.TSC (164 KB) - TINA-TI Reference Design
SBOM668.ZIP (9 KB) - TINA-TI Spice Model
SBOMBK9.TSC (38 KB) - TINA-TI Spice Model
PSpice® for TI design and simulation tool
PSPICE-FOR-TI — PSpice® for TI is a design and simulation environment that helps evaluate functionality of analog circuits. This full-featured, design and simulation suite uses an analog analysis engine from Cadence®. Available at no cost, PSpice for TI includes one of the largest model libraries in the (...)
  • Leverages Cadence PSpice Technology
  • Preinstalled library with a suite of digital models to enable worst-case timing analysis
  • Dynamic updates ensure you have access to most current device models
  • Optimized for simulation speed without loss of accuracy
  • Supports simultaneous analysis of multiple products
  • (...)
SPICE-based analog simulation program
TINA-TI TINA-TI provides all the conventional DC, transient and frequency domain analysis of SPICE and much more. TINA has extensive post-processing capability that allows you to format results the way you want them. Virtual instruments allow you to select input waveforms and probe circuit nodes voltages (...)
document-generic User guide

Reference designs

Shunt Based Ground Fault Protection for Inverters Powered from 100/110Vac Supply Reference Design
TIDA-00439 This is a reference design for detecting ground fault in inverter-based drives. Inverter current is measured on both DC-positive and DC-negative bus using shunt resistors. INA149 current sense amplifier having a common-mode voltage range of +275 V is used to measure current on DC-positive bus (...)
document-generic Schematic
8-ch Isolated High Voltage Analog Input Module with ISOW7841 Reference Design
TIDA-01333 — The TIDA-01333 isolated high voltage analog input module reference design has eight channels supporting both, voltage and current measurement. In addition, 4 channels support common-mode voltages up to ±160V. Isolation of +5V line and the Serial Peripheral Interface  (SPI) communication (...)
document-generic Schematic
8-ch Isolated High Voltage Analog Input Module Reference Design
TIDA-00764 — This reference design is a high-voltage analog input module with eight channels. Each channel can be used for both voltage and current measurement. The design uses 16-bit analog-to-digital converter (ADC) ADS8681 that can handle input voltage of up to ±12.288 V. This make any (...)
document-generic Schematic

CAD/CAE symbols

Package Pins Download
SOIC (D) 8 View options

Ordering & quality

Information included:
  • RoHS
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring

Support & training

TI E2E™ forums with technical support from TI engineers

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​​​​​​​