Analog Devices Inc. ADA4940 Fully Differential ADC Drivers

Analog Devices Inc. ADA4940 Fully Differential ADC Drivers are low noise, low distortion differential amplifiers with very low power consumption. They are an ideal choice for driving low power, high resolution, high performance SAR and sigma-delta (Σ-Δ) analog-to-digital converters (ADCs) with resolutions up to 18 bits from dc to 1MHz on only 1.25mA of quiescent current.

With the ADA4940-1/ADA4940-2, differential gain configurations are easily realized with a simple external feedback network of four resistors determining the closed-loop gain of the amplifier. The ADA4940-1/ADA4940-2 are fabricated using Analog Devices Inc., complementary bipolar process, enabling them to achieve very low levels of distortion with an input voltage noise of only 3.9nV/√Hz. The low dc offset and excellent dynamic performance of the ADA4940-1/ADA4940-2 make them well suited for a variety of data acquisition and signal processing applications.

Analog Devices offers the ADA4940-1AR-EBZ 8-Lead SOIC and ADA4940-1ACP-EBZ 8-Lead SOIC evaluation boards to help designers test the features of the ADA4940 Fully Differential ADC Drivers. These are bare boards with no components soldered to the them. The bare board enables designers to customize the circuit and quickly prototype a variety of differential amplifier circuits.


  • 260MHz Small signal bandwidth
  • Extremely low harmonic distortion
  • -122dB THD at 50kHz
  • -96dB THD at 1MHz
  • 3.9nV/√Hz Low input voltage noise
  • 6.25mW (5V supply) Very low power consumption
  • 0.35mV maximum offset voltage
  • Externally adjustable gain
  • Differential-to-differential or single-to-differential operation
  • Balanced outputs
  • 34ns Settling time to 0.1%
  • Output voltage swing from -VS + 0.1V to +VS -0.1V
  • Adjustable output common-mode voltage
  • Flexible power supplies: 3V to 7V


  • Low power ADC drivers
  • Single-ended-to-differential converters
  • Differential buffers
  • Line drivers
  • Medical imaging
  • Industrial process control
  • Portable electronics

Functional Block Diagrams

Analog Devices Inc. ADA4940 Fully Differential ADC Drivers
Published: 2013-04-23 | Updated: 2022-03-11