The AD629 is a difference amplifier with a very high input, common-mode voltage range. It is a precision device that allows the user to accurately measure differential signals in the presence of high common-mode voltages up to ±270 V.
The AD629 can replace costly isolation amplifiers in applications that do not require galvanic isolation. The device operates over a ±270 V common-mode voltage range and has inputs that are protected from common-mode or differential mode transients up to ±500 V.
The AD629 has low offset, low offset drift, low gain error drift, low common-mode rejection drift, and excellent CMRR over a wide frequency range.
The AD629 is available in low cost, 8-lead PDIP and 8-lead SOIC packages. For all packages (including die) and grades, performance is guaranteed over the industrial temperature range of −40°C to +85°C.
|Title||Content Type||File Type|
|AD629: High Common-Mode Voltage, Difference Amplifier Data Sheet (Rev C, 04/2011) (pdf, 534 kB)||Data Sheets|
|AN-244: A User's Guide to I.C. Instrumentation Amplifiers (pdf, 522 kB)||Application Notes|
AN-245: Instrumentation Amplifiers Solve Unusual Design Problems
(pdf, 543 kB)
Traditionally Considered Only for Transducer-Conditioning Applications, Instrumentation Amplifiers Bring Unique Performance Benefits to a Range of Other Applications as Well.
|AN-671: Reducing RFI Rectification Errors in In-Amp Circuits (pdf, 208 kB)||Application Notes|
AN-589: Ways to Optimize the Performance of a Difference Amplifier
(pdf, 115 kB)
This Application Note presents several ways to build and optimize the performance of a discrete difference amplifier. It also recommends amplifiers that will make the overall solution cost/performance competitive with monolithic instrument amplifiers.
|CN-0240: Bidirectional Isolated High-Side Current Sense with 270 V Common-Mode Rejection (pdf, 336 kB)||Circuit Note|
|CN-0100: Measuring −48 V High-Side Current Using the AD629 Difference Amplifier, AD8603 Op Amp, AD780 Reference, and AD7453 12-Bit ADC Single-Supply Components (pdf, 108 kB)||Circuit Note|
|A Designer's Guide to Instrumentation Amplifiers (3rd Edition)||Design Handbooks||HTML|
Finding the Needle in a Haystack: Measuring small differential voltages in the presence of large common-mode voltages
(Analog Dialogue, Vol. 34, No. 1, January-February, 2000)
(doc, 75 kB)
A wide variety of electronic applications, especially those involving very small input signals, require signal paths with very low offset voltage and offset voltage drift over time and temperature.
High-performance Adder Uses Instrumentation Amplifiers
Make an adder circuit using instrumentation amplifiers to increase input impedance.
High-Voltage Monitor Features High Accuracy
... Article is on page 3 of PDF.
(Electronic Design, Ideas for Design, 8/19/2002)
Input Filter Prevents Instrumentation-amp RF-Rectification Errors
by Charles Kitchin, Lew Counts, and Moshe Gerstenhaber, Analog Devices, Inc. (EDN, 11/13/2003)
|The AD8221 - Setting a New Industry Standard for Instrumentation Amplifiers (pdf, 582 kB)||Technical Articles|
|Applying Instrumentation Amplifiers Effectively: The Importance of an Input Ground Return (pdf, 508 kB)||Technical Documentation|
|Leading Inside Advertorials: Applying Instrumentation Amplifiers EffectivelyThe Importance of an Input Ground Return (pdf, 121 kB)||Overview|
|RAQs index||Rarely Asked Questions||HTML|
|Glossary of EE Terms||Glossary||HTML|
|Title||Content Type||File Type|
|AD629 SPICE Macro-Models||SPICE Models||HTML|
Symbols and Footprints— Analog Devices offers Symbols & Footprints which are compatible with a large set of today’s CAD systems for broader and easier support.
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.