AD8429 In-Amp

Norwood, MA (06/22/2011) - Analog Devices, Inc. (ADI) today introduced an ultra-low noise, low-power low-distortion instrumentation amplifier (in amp) for the precision measurement of extremely small signals present in noisy industrial operating environments. Tracing its lineage back to ADI's market-leading AD620 low-drift, low-power in amp, the new high-bandwidth AD8429 in amp is one of the fastest in amps on the market with a current feedback architecture that offers 15 MHz (G=1) bandwidth and a 22-V/μs slew rate, which is 30 percent higher than competing in amps. With a low distortion of -130-dB, the AD8429 is robust enough for applications that demand reduced size, power and distortion levels, such as healthcare instrumentation, precision data acquisition equipment and industrial vibration analysis.

With 1-nV/√Hz input noise and 45-nV/√Hz output noise, the AD8429 operates across the extended industrial temperature range of -40˚C to 125˚C. Input bias current of 300-nA is orders of magnitude lower than the 12,000-nA bias current of other in amps, while the 150-μV input offset voltage of the AD8429 is two to three times lower.

The AD8429 has a 90-dB CMRR (common-mode rejection ratio) when operating in dc mode and an 80-dB CMRR in ac mode, which prevents unwanted signals from corrupting smaller signal acquisition. The CMRR increases with the gain to provide high signal rejection when it is needed most, and ADI’s high-performance pin configuration allows the AD8429 to reliably maintain high CMRR at frequencies well beyond those of typical instrumentation amplifiers. This high-level of precision performance is available in a 4-mm x 5-mm, JEDEC compliant, plastic SOIC_N (small outline package, narrow body) package.

The AD8429 provides analog design engineers with a versatile, flexible in amp featuring a ±4-V to ±18-V dual power supply. Gain is set from 1 to 10,000 with a single resistor, and 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.

AD8429 Ultra Low Noise, Low Distortion Instrumentation Amplifier Key Features:

  • Low noise
    • 1-nV/√Hz input noise
    • 45-nV/√Hz output noise
  • High accuracy dc performance
    • 90-dB CMRR minimum (G = 1)
    • 150-μV maximum input offset voltage
    • 0.02 percent maximum gain accuracy (G = 1)
  • Excellent ac specifications
    • 80-dB CMRR to 5 kHz (G = 1)
    • 15-MHz bandwidth (G = 1)
    • 22-V/μs slew rate

Availability and Pricing

Product Availability Temperature Range Price Each Per 1,000 Packaging
AD8429 Full volume production now -40˚C to 125˚C $3.50 8-lead SOIC

About Analog Devices

Innovation, performance, and excellence are the cultural pillars on which Analog Devices has built one of the longest standing, highest growth companies within the technology sector. Acknowledged industry-wide as the world leader in data conversion and signal conditioning technology, Analog Devices serves over 100,000 customers, representing virtually all types of electronic equipment. Analog Devices is headquartered in Norwood, Massachusetts, with design and manufacturing facilities throughout the world. Analog Devices is included in the S&P 500 Index.

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Editor's Contact Information:

Bob Olson

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