Analog Devices Inc. ADA4666-2ARMZ-RL

Overview

ADA4666-2ARMZ-RL from Analog Devices is a dual CMOS rail-to-rail input/output operational amplifier optimized for low-power, wide-supply-voltage operation (3 V to 18 V), delivering 4 MHz gain bandwidth, 725 µA supply current per amplifier, and 2.2 mV max input offset voltage over full common-mode range. It serves precision signal conditioning in battery-powered instrumentation and high-impedance sensor interfaces.

For engineers reviewing the ADA4666-2ARMZ-RL datasheet, ADA4666-2ARMZ-RL pinout, ADA4666-2ARMZ-RL application, or ADA4666-2ARMZ-RL equivalent, key selection criteria include rail-to-rail I/O swing at 3–18 V supplies, sub-1 mA quiescent current, 15 pA max input bias current, and guaranteed −40°C to +125°C operation in MSOP and LFCSP packages.

Technical Context

The ADA4666-2ARMZ-RL employs a CMOS input stage enabling ultra-low input bias current (≤15 pA) and high input impedance (>10 GΩ), paired with a rail-to-rail output stage capable of sourcing/sinking ±40 mA continuously. Its unity-gain stable architecture supports closed-loop bandwidths up to 2.1 MHz at AV = 1 and delivers 60° phase margin with 10 pF capacitive load.

It features matched dual-channel topology with 80 dB typical channel separation at 10 kHz, EMI rejection ratio up to 60 dB at 2.4 GHz, and robust rail-to-rail input common-mode range (0 V to V_S) across all supply voltages - critical for single-supply current shunt monitor topologies and active filter designs requiring full dynamic range utilization.

Key Specifications

Pinout & Package

ADA4666-2ARMZ-RL is available in an 8-lead MSOP package (3 mm × 3 mm, 0.8 mm height) with exposed pad option. Pin assignments are identical for both MSOP and LFCSP variants per Analog Devices' pin configuration diagrams.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual precision op amp applications.

Compared with AD8657ARZ and ADA4096-2ARZ, ADA4666-2ARMZ-RL uniquely balances 4 MHz bandwidth, 725 µA supply current, and 3–18 V operation across −40°C to +125°C - making it the only dual op amp in this group supporting 12 V industrial signal chains with <2.2 mV offset and rail-to-rail swing.

Availability

ADA4666-2ARMZ-RL is available at Aetrix Electronics and suitable for current shunt monitors, active filters, portable medical equipment, buffer/level shifting, high-impedance sensor interfaces, and battery-powered instrumentation requiring stable component supply and long-term industrial-grade availability.

Supply support for ADA4666-2ARMZ-RL 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 ADA4666-2ARMZ-RL belongs to Analog Devices' precision low-power op amp product line, engineered for applications demanding rail-to-rail operation, wide supply range, and guaranteed performance across extended temperature extremes.

FAQ

What is the maximum supply voltage rating for the ADA4666-2ARMZ-RL?

The ADA4666-2ARMZ-RL has an absolute maximum supply voltage rating of 20.5 V, as specified in its Absolute Maximum Ratings table. Operation beyond this voltage risks permanent damage. The device is fully characterized from 3 V to 18 V, with electrical specifications guaranteed at 3.0 V, 10 V, and 18 V nominal supplies - making ADA4666-2ARMZ-RL suitable for 12 V and 15 V industrial rails while maintaining rail-to-rail functionality.

Does the ADA4666-2ARMZ-RL support true rail-to-rail input and output operation?

Yes, the ADA4666-2ARMZ-RL supports true rail-to-rail input (common-mode range from V− to V+) and rail-to-rail output (swing within 25 mV of V− and 17.95 V of V+ at 10 kΩ load, 18 V supply). This capability is verified across all supply voltages (3 V, 10 V, 18 V) and temperature ranges (−40°C to +125°C), enabling direct interfacing with ADCs and DACs without external level-shifting circuitry in ADA4666-2ARMZ-RL-based designs.

What is the input bias current specification for the ADA4666-2ARMZ-RL at 125°C?

At +125°C, the ADA4666-2ARMZ-RL specifies a maximum input bias current of 900 pA for 18 V operation and 750 pA for 10 V operation, as documented in Tables 2 and 3 of the datasheet. These values reflect worst-case conditions across process and temperature; typical performance remains below 100 pA. This elevated bias at high temperature is inherent to CMOS input stages but remains sufficiently low to avoid significant error in most high-Z sensor applications when using ADA4666-2ARMZ-RL.

Can the ADA4666-2ARMZ-RL drive capacitive loads without instability?

The ADA4666-2ARMZ-RL is unity-gain stable and maintains 60° phase margin with 10 pF capacitive load, as confirmed in Figure 35 (open-loop gain/phase vs. frequency) and Figure 46 (small-signal overshoot vs. load capacitance). For loads exceeding 10 pF, external isolation resistors (e.g., 10–100 Ω in series with the output) are recommended to preserve stability. This behavior is consistent across all supply voltages and makes ADA4666-2ARMZ-RL suitable for driving ADC input capacitors and long PCB traces.

Is the ADA4666-2ARMZ-RL pin-compatible with other dual op amps in the same package?

The ADA4666-2ARMZ-RL uses a standard 8-lead MSOP pinout (OUT A, −IN A, +IN A, V−, +IN B, −IN B, OUT B, V+) that matches industry conventions for dual op amps - however, no datasheet or Analog Devices documentation states pin compatibility with alternate part numbers. Substituting ADA4666-2ARMZ-RL requires verification of electrical parameters (e.g., supply range, offset, bandwidth) and thermal design, as pinout similarity does not guarantee functional equivalence. Always validate ADA4666-2ARMZ-RL in target circuitry before replacement.