Analog Devices Inc. AD622ARZ

Overview

AD622ARZ 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), ±2.6 V to ±15 V supply operation, 125 µV max input offset voltage, and 800 kHz bandwidth at G = 10 - used for precision transducer signal conditioning in industrial sensor interfaces.

For engineers reviewing the AD622ARZ datasheet, AD622ARZ pinout, AD622ARZ application, or AD622ARZ equivalent, key selection considerations include gain-setting resistor dependency, RTI noise performance (0.6 µV p-p, 0.1 Hz–10 Hz, G = 10), common-mode rejection (86 dB min at G = 10), and SOIC_N thermal resistance (θJA = 155°C/W).

Technical Context

The AD622ARZ 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 low input bias current (5 nA max) and stable transconductance scaling with gain.

Gain is set by RG between Pins 1 and 8 per G = 1 + (50.5 kΩ/RG); reference terminal (Pin 5) allows output offset injection within ±(VS – 1.6 V). Internal trimming ensures <0.5% gain error at G = 1000 and <10 ppm nonlinearity (RL = 10 kΩ).

Key Specifications

Pinout & Package

AD622ARZ is housed in an 8-lead SOIC_N (R-8) package, 5.00 mm × 4.00 mm × 1.50 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, the AD622ARZ delivers the best balance of cost, noise (12 nV/√Hz), and ease of use (unity-gain no-resistor operation) for industrial transducer interfaces - while AD8221ARMZ targets premium medical accuracy and AD8226ARMZ serves ultra-low-power edge nodes.

Availability

AD622ARZ 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 (–40°C to +85°C).

Supply support for AD622ARZ 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 is a global semiconductor leader specializing in high-performance analog, mixed-signal, and digital signal processing technologies for precision measurement and control.

The AD622ARZ belongs to Analog Devices' instrumentation amplifier product line, engineered specifically for cost-sensitive industrial sensing applications requiring robust common-mode rejection, low offset, and simple gain configuration.

FAQ

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

The AD622ARZ supports gains from 1 to 1000. Gain of 1 requires no external resistor (RG pins left open). For gains 2–1000, a single external resistor RG is connected between Pins 1 and 8, calculated using G = 1 + (50.5 kΩ/RG). The AD622ARZ datasheet Table 6 lists standard 1% resistor values - e.g., 511 Ω yields G ≈ 100. Gain accuracy degrades above G = 1000 due to internal limitations.

Does the AD622ARZ require external components for basic operation at gain = 1?

No, the AD622ARZ operates at unity gain with no external components beyond standard power supply decoupling capacitors (e.g., 0.1 µF ceramic near +VS and –VS pins). Pins 1 and 8 (RG) remain unconnected, Pin 5 (REF) is tied to ground or desired output offset voltage, and inputs are applied to Pins 2 (–IN) and 3 (+IN). This minimal BOM reduces cost and board area versus discrete op-amp alternatives.

What is the input voltage range specification for the AD622ARZ at ±15 V supplies?

At ±15 V supplies, the AD622ARZ input voltage range is –VS + 1.9 V to +VS – 1.4 V, i.e., –13.1 V to +13.6 V for differential input signals (one input grounded). Over temperature (–40°C to +85°C), this tightens to –12.9 V to +13.5 V. Exceeding these limits risks clipping or increased distortion; input protection resistors are recommended for signals beyond rails.

How does the REF pin function in the AD622ARZ and what voltage range is allowed?

The REF pin (Pin 5) of the AD622ARZ defines the output's zero-reference level. It accepts voltages from (–VS + 1.6 V) to (+VS – 1.6 V) - e.g., –13.4 V to +13.4 V at ±15 V supplies. Driving REF with a precision voltage (e.g., DAC output or bandgap reference) injects a controlled offset into the output without affecting gain or CMRR. Parasitic resistance on REF must be minimized (<10 Ω) to preserve CMRR performance.

What thermal considerations apply to the AD622ARZ in SOIC_N package?

The AD622ARZ in SOIC_N (R-8) package has a junction-to-ambient thermal resistance (θJA) of 155°C/W. At maximum 1.5 mA quiescent current and ±15 V supplies (45 mW dissipation), self-heating reaches ~7°C above ambient - negligible for most applications. For high-temperature environments (>70°C ambient), ensure adequate PCB copper pour under the package and avoid stacking heat-generating components nearby to maintain specified offset drift (1.0 µV/°C) and gain stability.