Overview
Features and Benefits
- Low noise
1 nV/√Hz input noise
45 nV/√Hz output noise - High accuracy dc performance (AD8429BRZ)
90 dB CMRR minimum (G = 1)
50 μV maximum input offset voltage
0.02% maximum gain accuracy (G = 1) - Excellent ac specifications
80 dB CMRR to 5 kHz (G = 1)
15 MHz bandwidth (G = 1)
1.2 MHz bandwidth (G = 100)
22 V/μs slew rate
THD: −130 dBc (1 kHz, G = 1) - Versatile
±4 V to ±18 V dual supply
Gain set with a single resistor
(G = 1 to 10,000) - Temperature range for specified performance
−40°C to +125°C
Product Details
The AD8429 is an ultralow noise, instrumentation amplifier designed for measuring extremely small signals over a wide temperature range (−40°C to +125°C).The AD8429 excels at measuring tiny signals. It delivers ultralow input noise performance of 1 nV/√Hz. The high CMRR of the AD8429 prevents unwanted signals from corrupting the acqui-sition. The CMRR increases as the gain increases, offering high rejection when it is most needed. The high performance pin configuration of the AD8429 allows it to reliably maintain high CMRR at frequencies well beyond those of typical instrumentation amplifiers.
The AD8429 reliably amplifies fast changing signals. Its current feedback architecture provides high bandwidth at high gain, for example, 1.2 MHz at G = 100. The design includes circuitry to im-prove settling time after large input voltage transients. The AD8429 was designed for excellent distortion performance, allowing use in demanding applications such as vibration analysis.
Gain is set from 1 to 10,000 with a single resistor. A reference pin allows the user to offset the output voltage. This feature can be useful to shift the output level when interfacing to a single supply signal chain. The AD8429 performance is specified over the extended industrial temperature range of −40°C to +125°C. It is available in an 8-lead plastic SOIC package.
APPLICATIONS
- Medical instrumentation
- Precision data acquisition
- Microphone preamplification
- Vibration analysis
Product Categories
Markets & Technology
Product Lifecycle
Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Documentation
Technical Books (1)
Tools & Simulations
LTspice
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.

Models for the following parts are available in LTspice:
In-Amp Diamond Plot Tool
The Diamond Plot Tool is a web application that generates a configuration-specific Output Voltage Range vs. Input Common-Mode Voltage graph, also known as the Diamond Plot, for Analog Devices Instrumentation Amplifiers. Based on user inputs such as supply voltage, gain, and input signal range, the tool detects saturation and recommends in-amps for which the input signal is in-range and the configuration is valid. Avoid saturation, find the best in-amp for your design, and save time.

SPICE Models
Reference Materials
Rarely Asked Questions (1)
Design Resources
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Support & Discussions
AD8429 Discussions
Sample & Buy
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.