Analog Devices Inc. AD627ARZ-R7

Overview

AD627ARZ-R7 from Analog Devices is a micropower, rail-to-rail output instrumentation amplifier optimized for low-power precision signal conditioning in single- and dual-supply systems. It delivers 85 μA max supply current, ±18 V / +36 V wide supply range, and 80 kHz bandwidth at G = +5 - enabling use in battery-powered ECG front-ends and 4 mA–20 mA loop receivers where power, accuracy, and dynamic range are critical.

For engineers reviewing the AD627ARZ-R7 datasheet, AD627ARZ-R7 pinout, AD627ARZ-R7 application, or AD627ARZ-R7 equivalent, key selection criteria include its resistor-programmable gain (5–1000), rail-to-rail output swing on 2.2 V single supply, 125 μV max input offset (AD627B grade), 77–83 dB CMRR at 50/60 Hz, and SOIC_N-8 package compatibility with legacy instrumentation layouts.

Technical Context

The AD627ARZ-R7 implements a modified current-feedback architecture with interstage feedforward compensation to maintain high CMRR (>83 dB) up to 200 Hz - essential for rejecting line-frequency interference in medical and industrial transducer interfaces. Its two-op-amp topology integrates laser-trimmed thin-film resistors (R1–R4) to achieve 0.03% typical gain accuracy at G = +5 and <10 ppm/°C gain drift.

Gain is set by a single external resistor across pins 1 and 8 per Gain = 5 + (200 kΩ/R_G); no internal gain-setting network is required. The REF pin provides precise output level-shifting capability, supporting bipolar signal amplification and ground-isolated load interfacing without additional op amps.

Key Specifications

Pinout & Package

AD627ARZ-R7 is housed in an 8-lead SOIC_N (R-8) package with standard industry pinout and 1.27 mm pitch. This RoHS-compliant surface-mount package measures 4.9 mm × 3.9 mm × 1.75 mm and supports reflow soldering per JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD8221ARMZ and INA333AIDR, AD627ARZ-R7 uniquely balances micropower (85 μA), wide supply range (±18 V / +36 V), and rail-to-rail output - making it the only option qualified for long-life, dual-rail industrial sensors and battery-operated medical wearables without performance trade-offs.

Availability

AD627ARZ-R7 is available at Aetrix Electronics and suitable for ECG front-end amplifiers, 4 mA–20 mA loop receivers, thermocouple signal conditioners, and portable pH meter designs requiring stable component supply across multi-year production cycles.

Supply support for AD627ARZ-R7 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 AD627 belongs to Analog Devices' precision instrumentation amplifier product line, engineered specifically for low-power, high-accuracy sensor signal conditioning in medical, industrial, and test equipment where micropower operation and rail-to-rail output are non-negotiable.

FAQ

What is the maximum gain achievable with AD627ARZ-R7?

The AD627ARZ-R7 supports a gain range of 5 to 1000, set by an external resistor between pins 1 and 8 using Gain = 5 + (200 kΩ/R_G). At G = 1000, R_G = 205 Ω (1% tolerance). Bandwidth reduces to 0.4 kHz at this gain, and output swing remains rail-to-rail under 100 kΩ load. The AD627ARZ-R7 datasheet specifies 0.50% max gain error at G = 1000 for the AD627A grade.

Does AD627ARZ-R7 support true single-supply operation down to 2.2 V?

Yes, AD627ARZ-R7 operates from +2.2 V to +36 V single supply, with rail-to-rail output swing and valid input common-mode range from (−V_S) − 0.1 V to (+V_S) − 1 V - meaning it accepts inputs within 100 mV of ground and delivers outputs within 25 mV of V_CC at light loads. This enables direct interfacing to 3 V microcontrollers and ADCs without level-shifting circuitry.

How does the REF pin function in AD627ARZ-R7?

The REF pin defines the output's zero-reference voltage: V_OUT = (V_+IN − V_−IN) × Gain + V_REF. Driving REF with a low-impedance source (e.g., DAC output or resistive divider) shifts the entire output range without affecting gain or CMRR. For optimal performance, REF must be driven from ≤125 kΩ source impedance, as specified in the AD627ARZ-R7 datasheet.

What is the input bias current specification for AD627ARZ-R7?

AD627ARZ-R7 has a maximum input bias current of 10 nA at 25°C (dual supply) and 15 nA over temperature - critical for interfacing with high-impedance sources like pH electrodes or piezoelectric sensors. Its FET-input-like behavior stems from the internal current-feedback topology, and bias current remains stable across common-mode voltage (−V_S − 0.1 V to +V_S − 1 V).

Is AD627ARZ-R7 pin-compatible with other Analog Devices instrumentation amplifiers?

No, AD627ARZ-R7 uses an 8-lead SOIC_N package with a unique pinout (RG on pins 1 & 8, REF on pin 5) that differs from AD620, AD8221, or INA128. While all are instrumentation amplifiers, direct pin replacement is not possible. Layout redesign is required when substituting AD627ARZ-R7 into existing footprints - confirmed by Analog Devices' Pin Configurations section (Rev. E, Page 8).