ADA4940-1ARZ-R7

Overview

The ADA4940-1ARZ-R7 is a fully differential amplifier from Analog Devices, designed as an ultralow power and low distortion ADC driver. It features a small signal bandwidth of 260 MHz and a slew rate of 95 V/µs. The device operates on flexible power supplies ranging from 3 V to 7 V (LFCSP) or 3 V to 6 V (SOIC), consuming only 1.25 mA of quiescent current per amplifier when enabled. It provides balanced outputs with an adjustable output common-mode voltage and includes a disable pin for power reduction.

Feature Summary

• Ultralow power consumption with 1.25 mA quiescent current
• Extremely low harmonic distortion performance
• Low input voltage noise density
• Adjustable output common-mode voltage

Applications

• Low power PulSAR/SAR ADC drivers
• Single-ended-to-differential conversion
• Differential buffers
• Line drivers
• Medical imaging systems

Procurement Notes

Verify the specific package type against the ordering suffix, as the ARZ designation indicates an SOIC package variant. Confirm that the required supply voltage range aligns with the SOIC operational limits of 3 V to 6 V. Ensure the disable pin functionality meets system power management requirements. Check for moisture sensitivity handling if the LFCSP alternative was originally considered.

Selection Notes

Select this component when driving high-resolution SAR or Sigma-Delta ADCs requiring minimal power consumption. The SOIC package offers a larger footprint compared to the LFCSP option, which may simplify PCB layout for certain designs. Consider the 260 MHz bandwidth for applications requiring wide dynamic range. Verify that the 0.35 mV maximum offset voltage meets the precision requirements of the target data acquisition chain.

Part Context

The ADA4940-1ARZ-R7 belongs to the ADA4940 family of fully differential amplifiers manufactured using a SiGe complementary bipolar process. This technology enables low distortion and noise characteristics suitable for precision signal processing. The part is specified for operation over a temperature range of -40°C to +125°C, ensuring reliability in industrial and portable electronic environments.

Replacement Considerations

The ADA4940-1ACPZ-R7 serves as a direct functional replacement but utilizes a 16-lead LFCSP package instead of the SOIC form factor. Designers must account for differences in thermal resistance and physical footprint when substituting. Other family members like the ADA4940-2 offer dual-channel configurations.