Analog Devices Inc. ADA4084-1ARZ-R7

Overview

ADA4084-1ARZ-R7 from Analog Devices is a single-channel, rail-to-rail input/output precision operational amplifier optimized for low-noise, low-power, wide-supply applications. It delivers 15.9 MHz gain bandwidth, 4.6 V/µs slew rate, and 3.9 nV/√Hz voltage noise at 1 kHz, operating from ±1.5 V to ±15 V (or +3 V to +30 V). It is used in high-accuracy ADC input buffers and DAC output amplifiers where signal integrity and dc precision are critical.

For engineers reviewing the ADA4084-1ARZ-R7 datasheet, ADA4084-1ARZ-R7 pinout, ADA4084-1ARZ-R7 application, or ADA4084-1ARZ-R7 equivalent, this page provides verified specifications, SOIC-8 package details, real-world use cases in instrumentation and power control, and two validated alternative op amps with documented functional and parametric differences.

Technical Context

The ADA4084-1ARZ-R7 employs a folded-cascode architecture enabling rail-to-rail input common-mode range (−15 V to +15 V at ±15 V supply) and rail-to-rail output swing (within 10 mV of rails at light load). Its unity-gain stability and 86° phase margin support robust closed-loop performance in active filters and precision gain stages without external compensation.

It features low input bias current (250 nA typ), high CMRR (124 dB max at ±5 V), and exceptional long-term offset stability (3 µV typical drift over 10,000 hours), making it suitable for high-impedance sensor interfaces and battery-powered measurement systems requiring minimal calibration.

Key Specifications

Pinout & Package

The ADA4084-1ARZ-R7 is packaged in an 8-lead SOIC_N (R-8) with exposed pad not present; pin 1 is NC, pins 2–3–4–6–7–8 serve as −IN, +IN, V−, OUT, V+, and NC respectively. Thermal resistance θ_JA = 121°C/W on standard 4-layer PCB.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar precision operational amplifier applications.

Compared with AD8671ARZ and OP27GSZ-REEL7, the ADA4084-1ARZ-R7 uniquely balances rail-to-rail operation, 3.9 nV/√Hz noise, and sub-1 mA quiescent current across +3 V to +30 V - making it the only option among the three viable for both battery-powered portables and wide-input industrial supplies without performance trade-offs.

Availability

ADA4084-1ARZ-R7 is available at Aetrix Electronics and suitable for battery-powered instrumentation, high-side/low-side current sensing, and precision ADC/DAC interfacing requiring stable component supply across extended temperature and voltage ranges.

Supply support for ADA4084-1ARZ-R7 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA.

The ADA4084 family was designed specifically for precision, low-noise, wide-supply operational amplification in industrial, instrumentation, and medical applications demanding rail-to-rail performance and long-term stability.

FAQ

What supply voltage range does the ADA4084-1ARZ-R7 support?

The ADA4084-1ARZ-R7 operates from ±1.5 V to ±15 V (dual supply) or +3 V to +30 V (single supply), with full specification guaranteed across this range. At ±15 V, it delivers 4.6 V/µs slew rate and 15.9 MHz gain bandwidth while consuming only 0.625 mA per amplifier - enabling flexible use in both legacy ±15 V test gear and modern 3.3 V/5 V/24 V industrial systems without redesign.

Is the ADA4084-1ARZ-R7 unity-gain stable?

Yes, the ADA4084-1ARZ-R7 is explicitly unity-gain stable with 86° phase margin at AV = 1, as confirmed in its datasheet (Rev. I, Table 2–4, "Phase Margin"). This allows direct use in voltage followers, active filters, and precision buffers without external compensation components - simplifying layout and improving reliability in high-accuracy signal chains where phase margin directly impacts settling behavior and overshoot.

What is the input offset voltage specification for ADA4084-1ARZ-R7?

The ADA4084-1ARZ-R7 has a maximum input offset voltage of 100 µV in the SOIC package at 25°C (Table 2–4), with worst-case 200 µV across −40°C to +125°C. This low offset, combined with 0.5 µV/°C typical drift, ensures minimal gain error in precision gain stages - for example, introducing only 0.002% error in a 5 V full-scale 10× amplifier, critical for calibrated sensor interfaces and automated test equipment.

Does ADA4084-1ARZ-R7 support rail-to-rail input and output?

Yes, the ADA4084-1ARZ-R7 features true rail-to-rail input (common-mode range extends to both supply rails) and rail-to-rail output (swings within 10 mV of V+ and V− at light load). At ±15 V supply, input range is −15 V to +15 V and output delivers ±14.9 V into 10 kΩ - enabling full utilization of ADC/DAC dynamic range in single-supply systems and eliminating need for external level-shifting circuitry in multistage analog signal paths.

What package type is used for ADA4084-1ARZ-R7?

The ADA4084-1ARZ-R7 is supplied in an 8-lead SOIC_N (R-8) package, RoHS-compliant and tape-and-reel packaged as indicated by the "R7" suffix. Its thermal resistance is θ_JA = 121°C/W on a standard 4-layer JEDEC board, and pinout follows industry-standard SOIC orientation with NC pins at positions 1, 5, and 8 - simplifying footprint reuse in legacy designs migrating from similar op amps like OP27 or AD8671.