AD8428 Low Noise, Low Gain Drift, G = 2000 Instrumentation Amplifier

The AD8428 is an ultra-low noise instrumentation amplifier designed for accurately measuring tiny, high-speed signals. It delivers industry-leading gain-accuracy, noise and bandwidth.

All gain setting resistors for the AD8428 are internal to the part and precisely matched. Care is taken in both interconnects and symmetry. This results in excellent gain drift and quick settling to the final gain value after the part is powered on.

The high CMRR of the AD8428 prevents unwanted signals from corrupting the acquisition. The part’s pin-out is designed to avoid parasitic capacitance mismatches that can degrade CMRR at high frequencies.

The AD8428 is one of the fastest instrumentation amplifiers available. The circuit architecture is designed for high bandwidth at high gain: it uses current feedback topology for the initial pre-amp gain stage of 200, followed by a difference amplifier stage of 10. This results in a 3.5 MHz bandwidth at a gain of 2000, for an equivalent gain-bandwidth product of 7 GHz.

The AD8428 pinout allows access to internal nodes between the first and second stage. This feature can be useful to modify DC and AC parameters between the two amplification stages.

The AD8428 performance is specified over the industrial temperature range of −40°C to +85°C. It is available in an 8-lead plastic SOIC package.

Applications
  • Sensor interface
  • Medical instrumentation
  • Patient monitoring
Features and Benefits
  • Fixed gain of 2000
  • Access to internal nodes provides flexibility
  • Low noise: 1.5 nV/√Hz input voltage noise
  • High accuracy dc performance
    Gain drift: 10 ppm/°C
    Offset drift: 1 μV/°C
    Gain accuracy: 0.2%
    CMRR: 130 dB min
  • Excellent ac specifications
    Bandwidth: 3.5 MHz
    Slew rate: 40 V/μs
  • Power supply range:
    ±4 V to ±18 V
  • 8-pin SOIC package
  • ESD protection >5000 V (HBM)
  • Temperature range for specified performance:
    −40°C to +85°C
  • Operational up to 125°C
  • Amplifiers
    Aerospace and Defense
    • Solutions
    SPICE Models
    Data Sheets
    Documentnote
    AD8428: Low Noise, Low Gain Drift, G = 2000 Instrumentation Amplifier Datasheet (Rev. A)PDF 372 kB
    Technical Books
    Documentnote
    Order Information
    Part NumberPackagePacking QtyTemp RangePrice 100-499Price 1000+RoHS
    AD8420ARMZ Production8 ld MSOPOTH 50-40 to 85C1.110.89Y
    AD8420ARMZ-R7 Production8 ld MSOPREEL 1000-40 to 85C1.110.89Y
    AD8420ARMZ-RL Production8 ld MSOPREEL 3000-40 to 85C1.110.89Y
    Evaluation Boards
    Part NumberDescriptionPriceRoHS
    EVAL-INAMP-ICF-RMZEvaluation Board for AD8420 and 823734.58Y
    AD8428:低噪声、低增益漂移、G = 2000仪表放大器 (Rev. A) ad8428
    AD8428: Low Noise, Low Gain Drift, G = 2000 Instrumentation Amplifier Datasheet (Rev. A) ad8428
    AD8428 SPICE Macro-Model ad8428