Analog Devices Inc. AD622ARZ-RL

Overview

AD622ARZ-RL from Analog Devices is a low-cost, monolithic instrumentation amplifier in 8-lead SOIC_N package, delivering gain of 1 (no external resistor) or 2–1000 (with single RG resistor), 125 µV max input offset voltage, 800 kHz bandwidth at G=10, and ±2.6 V to ±15 V dual supply operation - used for precision transducer signal conditioning in industrial sensor interfaces.

For engineers reviewing the AD622ARZ-RL datasheet, AD622ARZ-RL pinout, AD622ARZ-RL application, or AD622ARZ-RL equivalent, key selection considerations include gain-setting resistor dependency, RTI noise performance (0.6 µV p-p, 0.1–10 Hz, G=10), CMRR up to 118 dB at G=100, and SOIC_N thermal resistance (θJA = 155°C/W).

Technical Context

The AD622ARZ-RL implements a modified three-op-amp architecture with laser-trimmed internal 25.25 kΩ gain resistors, enabling accurate gain programming via external RG. Its bipolar input stage (Q1/Q2 differential pair) provides 5 nA max input bias current and supports rail-to-rail common-mode input range within supply limits.

Gain error is minimized by absolute-value trimming (0.15% max at G=1); output offset (1500 µV max) is divided by gain when referred-to-input; reference pin allows precise output DC offset injection (±2 V range relative to supplies), critical for single-supply or isolated load interfacing.

Key Specifications

Pinout & Package

AD622ARZ-RL uses an 8-lead SOIC_N (R-8) package, 5.00 mm × 4.00 mm × 1.25 mm body, with standard JEDEC MS-012-AA footprint and 1.27 mm lead pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD8221ARMZ and AD8226ARMZ, AD622ARZ-RL delivers the best balance of cost, noise, and CMRR for industrial transducer interfaces - offering 12 nV/√Hz noise and 118 dB CMRR at less than half the price of AD8221ARMZ while outperforming AD8226ARMZ in precision-critical applications.

Availability

AD622ARZ-RL is available at Aetrix Electronics and suitable for industrial process controls, transducer interface modules, and low-cost data acquisition systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for AD622ARZ-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 AD622ARZ-RL belongs to Analog Devices' precision instrumentation amplifier product line, engineered specifically for cost-sensitive industrial and sensor signal conditioning applications requiring robustness, ease of use, and guaranteed specifications over −40°C to +85°C.

FAQ

What is the maximum gain achievable with AD622ARZ-RL and how is it set?

The AD622ARZ-RL supports gains from 1 to 1000. Gain of 1 requires no external components - simply leave pins 1 and 8 (RG) unconnected. For gains >1, connect a single external resistor RG between pins 1 and 8, calculated as RG = 50.5 kΩ/(G − 1). At G=1000, RG = 51.1 Ω (1% tolerance recommended). The AD622ARZ-RL datasheet Table 6 lists standard 1% resistor values for common gains.

Does AD622ARZ-RL require external protection diodes for overvoltage inputs?

No - the AD622ARZ-RL features built-in input protection that safely withstands ±60 mA input current continuously at room temperature, even with power off. For sustained overvoltage beyond supply rails (>±18 V), a series current-limiting resistor (e.g., 1 kΩ) is recommended per input to restrict current to ≤6 mA. External diodes like BAV199 are optional and only needed for extreme ESD or lightning surge scenarios not covered by the internal protection.

Can AD622ARZ-RL operate from a single supply?

The AD622ARZ-RL is specified for dual-supply operation (±2.6 V to ±15 V) and does not support true single-supply operation. However, it can be biased for pseudo-single-supply use by setting REF to mid-supply (e.g., +7.5 V on +VS = +15 V, –VS = 0 V) and ensuring input common-mode voltage stays within −VS + 1.9 V to +VS − 1.2 V. Output swing will be limited to ~1.2 V above –VS and ~1.4 V below +VS. For native single-supply designs, consider AD8226 or AD8420 instead.

What is the purpose of the REF pin on AD622ARZ-RL and how should it be used?

On the AD622ARZ-RL, the REF pin (pin 5) defines the output's zero-volt reference level. It accepts voltages from −VS + 1.6 V to +VS − 1.6 V and directly offsets the output: VOUT = G × (V+IN − V−IN) + VREF. This enables level-shifting to match downstream ADC input ranges or isolate ground domains. For best CMRR, keep REF trace short and low-impedance; avoid series resistance >10 Ω. When unused, tie REF to ground or mid-supply - never leave floating.

How does AD622ARZ-RL compare to discrete two-op-amp instrumentation amplifier designs?

The AD622ARZ-RL replaces discrete two-op-amp in-amps by integrating laser-trimmed resistors, eliminating manual resistor matching and reducing board area by >40%. In a typical 4–20 mA loop receiver (Figure 17), AD622ARZ-RL achieves 3763 ppm total error vs. 5775 ppm for a discrete LT1013-based design - primarily due to superior CMRR (118 dB vs. 50 ppm mismatch), lower drift (3450 ppm vs. 4089 ppm), and reduced noise contribution. No external trimming or calibration is required.