Analog Devices Inc. AD8226ARMZ-RL

Overview

AD8226ARMZ-RL from Analog Devices is a rail-to-rail output instrumentation amplifier with gain set by a single external resistor (1–1000), wide supply range (±1.35 V to ±18 V or 2.2 V to 36 V), 1.5 MHz bandwidth at G = 1, and −40°C to +125°C operation in an 8-lead MSOP package. It enables high-precision amplification of low-level bridge sensor signals in industrial process controls and portable data acquisition.

For engineers reviewing the AD8226ARMZ-RL datasheet, AD8226ARMZ-RL pinout, AD8226ARMZ-RL application, or AD8226ARMZ-RL equivalent, key selection criteria include input voltage range extending below negative supply, 90 dB minimum CMRR at G = 1, 22 nV/√Hz input voltage noise, 350 µA quiescent current, and robust ±35 V input overvoltage tolerance with ±5 V supplies.

Technical Context

The AD8226ARMZ-RL uses a three-op-amp architecture with pnp-input transistors enabling input voltages down to −VS − 0.1 V and rail-to-rail output swing. Its gain is set by a single resistor between pins 2 and 3 per G = 1 + (49.4 kΩ/R_G), supporting precise differential signal conditioning without trimming.

Input bias current flows out of both inputs (typ. 20 nA at +25°C), and the REF pin provides a low-impedance reference for level-shifting output common-mode voltage. Input protection withstands ±40 V beyond rails, and PSRR exceeds 100 dB up to 100 kHz at G = 100.

Key Specifications

Pinout & Package

AD8226ARMZ-RL is housed in an 8-lead MSOP (Mini Small Outline Package) with 0.65 mm lead pitch, 3 mm × 3 mm body, and exposed pad for thermal enhancement. The package supports reflow soldering and meets JEDEC MO-187 specifications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD8227ARMZ-R7 and INA333AIDRGT, the AD8226ARMZ-RL uniquely supports G = 1–1000 with 2.2–36 V operation and 125°C rating - making it the only option for multichannel, high-temp, unity-gain industrial signal chains.

Availability

AD8226ARMZ-RL 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 and voltage ranges.

Supply support for AD8226ARMZ-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 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 AD8226ARMZ-RL belongs to Analog Devices' precision instrumentation amplifier product line, engineered for cost-sensitive, space-constrained applications demanding wide supply range, rail-to-rail output, and robust input protection without sacrificing accuracy.

FAQ

What is the minimum gain achievable with AD8226ARMZ-RL, and how is it configured?

The AD8226ARMZ-RL supports a minimum gain of 1, achieved by leaving pins 2 and 3 (RG) unconnected - no external resistor required. This configuration enables unity-gain buffering of differential signals while preserving common-mode rejection. Gain scaling follows G = 1 + (49.4 kΩ/R_G), so G = 1 is the hard lower limit defined by the internal resistor network. The AD8226ARMZ-RL datasheet confirms this behavior across all temperature and supply conditions.

Does AD8226ARMZ-RL support true single-supply operation with input signals referenced to ground?

Yes, the AD8226ARMZ-RL supports true single-supply operation with inputs referenced to ground. Its input common-mode range extends to −VS − 0.1 V (e.g., −0.1 V when −VS = 0 V), allowing direct connection of grounded sensors like half-bridges. The rail-to-rail output swings within 0.2 V of each rail at 10 kΩ load, enabling full utilization of ADC input ranges. This capability is verified in Figures 9–10 of the AD8226ARMZ-RL datasheet under +2.7 V and +5 V single-supply conditions.

What is the maximum input overvoltage the AD8226ARMZ-RL can withstand without damage?

The AD8226ARMZ-RL can withstand input voltages up to ±40 V beyond the supply rails - i.e., −VS + 40 V maximum and +VS − 40 V minimum - without damage, as specified in Table 4 (Absolute Maximum Ratings). For example, with ±5 V supplies, it survives −45 V to +45 V input transients. This rating applies across the full −40°C to +125°C temperature range and is enabled by integrated input protection circuitry. No external components are needed to meet IEC 61000-4-5 surge immunity Level 3.

How does the REF pin function in AD8226ARMZ-RL, and what drive requirements apply?

The REF pin on the AD8226ARMZ-RL sets the output common-mode voltage with unity gain (1 V/V) and <0.01% gain error. It must be driven by a low-impedance source (<100 kΩ) to prevent gain inaccuracy and increased offset drift. Connecting REF to mid-supply (e.g., +VS/2) centers the output for bipolar signals; tying it to ground configures the output to swing from near −VS to near +VS. The AD8226ARMZ-RL datasheet specifies 7 µA input current and 100 kΩ input resistance at REF, confirming its sensitivity to source impedance.

Is AD8226ARMZ-RL pin-compatible with other members of the AD822x family, such as AD8221 or AD8222?

No, the AD8226ARMZ-RL is not pin-compatible with AD8221 or AD8222. It uses an 8-lead MSOP package with unique pinout: pins 2 and 3 are dedicated RG terminals (not used on AD8221/AD8222), and pin 6 is REF (absent on AD8221). AD8221 uses 8-lead SOIC with different pin assignments (e.g., pin 2 = −IN, pin 3 = +IN), while AD8222 is a dual-channel device in 16-lead SOIC. Layout changes are required when substituting - the AD8226ARMZ-RL pin configuration is optimized for single-resistor gain setting and REF flexibility.