Analog Devices Inc. AD8226ARZ

Overview

AD8226ARZ from Analog Devices is a low-cost, rail-to-rail output instrumentation amplifier requiring only one external resistor to set gain from 1 to 1000. It operates from single supplies (2.2 V to 36 V) or dual supplies (±1.35 V to ±18 V), supports input voltages below ground, and delivers 1.5 MHz bandwidth at G = 1 - ideal for precision bridge sensor conditioning in industrial process controls.

For engineers reviewing the AD8226ARZ datasheet, AD8226ARZ pinout, AD8226ARZ application, or AD8226ARZ equivalent, key selection criteria include its wide supply range, input overvoltage tolerance (±40 V beyond rails), −40°C to +125°C operation, 22 nV/√Hz input voltage noise, and SOIC-8 package compatibility with space-constrained multichannel systems.

Technical Context

The AD8226ARZ employs a three-op-amp architecture with pnp-input transistors enabling true input voltage operation below the negative supply rail. Its gain is set by a single external resistor (RG) between Pins 2 and 3 per G = 1 + 49.4 kΩ/RG, supporting precise scaling without trimming.

Input protection handles ±40 V beyond supply rails under all conditions; reference input (Pin 6) provides level-shifting capability with 100 kΩ input impedance and 0.01% gain error. CMRR exceeds 90 dB at DC–60 Hz (G = 1) and remains ≥100 dB up to 5 kHz for G ≥ 100.

Key Specifications

Pinout & Package

AD8226ARZ is housed in an 8-lead SOIC package (body width 3.9 mm, JEDEC MS-012), compatible with standard surface-mount assembly and reflow profiles. Thermal resistance θJA = 121°C/W on 4-layer JEDEC board.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD8227ARZ and INA126PA, the AD8226ARZ uniquely combines G = 1 capability, sub-rail input, and 350 µA quiescent current - making it optimal for universal sensor interface where gain flexibility, supply simplicity, and power efficiency are jointly critical.

Availability

AD8226ARZ is available at Aetrix Electronics and suitable for industrial process controls, bridge amplifiers, medical instrumentation, and portable data acquisition requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for AD8226ARZ 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 leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets since 1965.

The AD8226ARZ belongs to Analog Devices' precision instrumentation amplifier product line, engineered specifically for robust, low-cost signal conditioning of millivolt-level sensor outputs in harsh, space-constrained, and thermally demanding environments.

FAQ

What is the minimum supply voltage required for AD8226ARZ operation?

The AD8226ARZ operates down to 2.2 V on single supply or ±1.35 V on dual supply. At 2.2 V, it maintains full functionality including rail-to-rail output swing and specified gain accuracy. This enables direct integration with Li-ion or coin-cell powered portable devices without boost regulation.

Can AD8226ARZ amplify signals below ground in single-supply configuration?

Yes, the AD8226ARZ supports input voltages as low as −VS − 0.15 V at −40°C - meaning with −VS tied to GND, it accepts inputs down to −0.15 V. This allows direct amplification of near-ground bridge outputs without level-shifting circuitry, preserving signal integrity and reducing component count.

How is gain set on AD8226ARZ, and what resistor value gives G = 100?

Gain is set by a single external resistor (RG) between Pins 2 and 3 using G = 1 + 49.4 kΩ/RG. For G = 100, RG = 49.4 kΩ / 99 ≈ 499 Ω. Standard 1% metal-film resistors (e.g., 499 Ω) achieve <0.15% gain error, eliminating need for trimming or calibration in most applications.

Does AD8226ARZ require external capacitors for stability?

No, the AD8226ARZ is internally compensated and stable with capacitive loads up to 1000 pF. No external compensation components are needed - simplifying layout and reducing bill-of-materials. However, a 0.1 µF bypass capacitor at each supply pin is recommended for noise suppression.

What is the maximum input overvoltage the AD8226ARZ can withstand without damage?

The AD8226ARZ withstands input voltages up to +VS − 40 V and −VS + 40 V across −40°C to +125°C. For example, with ±5 V supplies, it survives ±35 V applied to either input - providing robust protection against field wiring errors, ESD events, or inductive kickback in industrial settings.