AD8421-EP Datasheet

• Specified from −55°C to 125°C 
  • 0.9 μV/°C maximum input offset voltage drift
  • 5 ppm/°C maximum gain drift (G = 1) 
• Low power
  • 2.3 mA maximum supply current
• Low noise
  • 3.2 nV/√Hz maximum input voltage noise at 1 kHz
  • 200 fA/√Hz current noise at 1 kHz
• Excellent ac specifications 
  • 2 MHz bandwidth (G = 100)
  • 0.6 µs settling time to 0.001% (G = 10)
  • 80 dB CMRR to 20 kHz (G = 1)
• High precision dc performance
  • 84 dB CMRR minimum (G = 1)
  • 2 nA maximum input bias current
• Inputs protected to 40 V from opposite supply
• Gain set with a single resistor (G = 1 to 10,000)

ENHANCED PRODUCT FEATURES

• Supports defense and aerospace applications (AQEC standard)
• Military temperature range (−55°C to +125°C)
• Controlled manufacturing baseline
• One assembly/test site
• One fabrication site
• Enhanced product change notification
• Qualification data available on request

The AD8421-EP is a low cost, low power, extremely low noise,ultralow bias current, high speed instrumentation amplifier that is ideally suited for a broad spectrum of signal conditioning and data acquisition applications. This product features extremely high CMRR, allowing it to extract low level signals in the presence of high frequency common-mode noise over a wide temperature range.

The 10 MHz bandwidth, 35 V/μs slew rate, and 0.6 μs settling time to 0.001% (G = 10) allow the AD8421-EP to amplify high speed signals and excel in applications that require high channel count, multiplexed systems. Even at higher gains, the current feedback architecture maintains high performance; for example,at G = 100, the bandwidth is 2 MHz and the settling time is 0.8 μs. The AD8421-EP has excellent distortion performance,making it suitable for use in demanding applications such as vibration analysis.

The AD8421-EP delivers 3 nV/√Hz input voltage noise and 200 fA/√Hz current noise with only 2 mA quiescent current,making it an ideal choice for measuring low level signals. For applications with high source impedance, the AD8421-EP employs innovative process technology and design techniques to provide noise performance that is limited only by the sensor.

The AD8421-EP uses unique protection methods to ensure robust inputs while still maintaining very low noise. This protection allows input voltages up to 40 V from the opposite supply rail without damage to the part.

A single resistor sets the gain from 1 to 10,000. The referencepin can be used to apply a precise offset to the output voltage.

The AD8421-EP is specified over the military temperature range of −55°C to +125°C. It is available in an 8-lead MSOP package.

Additional application and technical information can be found in the AD8421 data sheet.