AD9631AR-REEL

Overview

The AD9631AR-REEL is a wide bandwidth, voltage feedback operational amplifier from Analog Devices. It features a small signal bandwidth of 320 MHz and a large signal bandwidth of 175 MHz at a gain of +1. The device offers a slew rate of 1300 V/µs and settles to 0.01% in 16 ns for a 2 V step. It operates on ±3 V to ±5 V supplies with a quiescent current of 17 mA. Key performance metrics include −113 dBc SFDR at 1 MHz and 7.0 nV/√Hz spectral noise density.

Feature Summary

• Unity gain stable voltage feedback architecture providing predictable design characteristics compared to current feedback alternatives.
• Exceptional pulse response and fast settling time suitable for high-speed transient applications.
• Ultralow harmonic distortion and low noise density optimized for precision signal processing.
• High slew rate enabling wide dynamic range operation without significant speed degradation.

Applications

• ADC input driver
• Differential amplifiers
• IF/RF amplifiers
• Pulse amplifiers
• Professional video

Procurement Notes

Verify the specific ordering suffix matches the required package type, as the REEL designation indicates tape and reel packaging. Confirm that the component grade meets the industrial temperature range requirements of −40°C to +85°C. Ensure power supply bypassing components are selected according to datasheet recommendations to maintain stability and minimize distortion during operation.

Selection Notes

Select this component when unity gain stability is required alongside wide bandwidth and low distortion. It serves as a direct performance upgrade over previous generations like the AD9621. Consider the voltage feedback topology for designs requiring active filters or transimpedance configurations where current feedback amplifiers are unsuitable. Evaluate feedback resistor values carefully to optimize bandwidth and phase margin.

Part Context

The AD9631 is part of a family of ultralow distortion, wide bandwidth voltage feedback op amps manufactured by Analog Devices. It is designed to replace older current feedback amplifiers while offering the predictability of classical op amp structures. The device is available in PDIP and SOIC packages, catering to both through-hole and surface-mount assembly needs in high-frequency electronic systems.

Replacement Considerations

The AD9631 is an improved performance alternative to the AD9621. Designers transitioning from current feedback architectures may find the voltage feedback structure more predictable. Verify that circuit layouts accommodate the specific feedback resistor requirements for optimal stability and bandwidth.

FAQ

Is the AD9631 stable at unity gain?

Yes, the AD9631 is specifically designed to be unity gain stable.

What is the typical spectral noise density of the AD9631?

The typical spectral noise density is 7.0 nV/√Hz.

How does the AD9631 compare to current feedback amplifiers?

It offers similar speed and bandwidth but provides the predictability and stability of a voltage feedback architecture, making it suitable for applications like active filters.