Analog Devices Inc. AD620BRZ-R7

Overview

AD620BRZ-R7 from Analog Devices is a low-cost, precision instrumentation amplifier with gain programmable from 1 to 10,000 via a single external resistor (RG), 50 μV max input offset voltage, 9 nV/√Hz input voltage noise at 1 kHz, and 1.3 mA max supply current. It operates from ±2.3 V to ±18 V supplies and is widely used in ECG front-ends, weigh scale signal conditioning, and bridge transducer interfaces.

For engineers reviewing the AD620BRZ-R7 datasheet, AD620BRZ-R7 pinout, AD620BRZ-R7 application, or AD620BRZ-R7 equivalent, this page delivers verified specifications, SOIC-8 package details, real-world use cases in medical and industrial sensing, and two validated alternative parts for design flexibility.

Technical Context

The AD620BRZ-R7 implements a monolithic, three-op-amp-based instrumentation amplifier architecture with Superβ bipolar input transistors enabling 1.0 nA max input bias current and 10 GΩ||2 pF input impedance. Its gain-setting network uses laser-trimmed internal 24.7 kΩ resistors, yielding accurate gain per G = 1 + 49.4 kΩ/RG.

It features a fully differential input stage followed by a unity-gain subtractor output stage referenced to the REF pin, delivering excellent common-mode rejection (100 dB min at G = 10) and high PSR (120 dB at G = 100). Settling time is 15 μs to 0.01% for gains ≤100, supporting multiplexed data acquisition systems.

Key Specifications

Pinout & Package

AD620BRZ-R7 is housed in an 8-lead SOIC (Small Outline Integrated Circuit) package, 3.9 mm × 4.9 mm footprint, 1.27 mm pitch, RoHS-compliant, and rated for −40°C to +85°C operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD8221ARMZ-R7 and AD8226ARMZ-R7, the AD620BRZ-R7 strikes a unique balance: it delivers B-grade precision (50 μV offset, 100 dB CMRR) at the lowest unit cost and 1.3 mA power - making it the go-to choice for volume production of portable medical and industrial instrumentation where performance and cost must coexist.

Availability

AD620BRZ-R7 is available at Aetrix Electronics and suitable for ECG monitor development, weigh scale manufacturing, and industrial transducer interface design requiring stable component supply and long-term production continuity.

Supply support for AD620BRZ-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 Wilmington, MA, with design centers worldwide.

The AD620BRZ-R7 belongs to Analog Devices' precision instrumentation amplifier product line, engineered specifically for low-noise, low-drift signal conditioning in medical diagnostics, industrial measurement, and sensor interface applications demanding accuracy, reliability, and ease of use.

FAQ

What is the maximum gain achievable with AD620BRZ-R7, and how is it set?

The AD620BRZ-R7 supports a gain range of 1 to 10,000, set by a single external resistor (RG) connected between Pins 1 and 8. The relationship is G = 1 + 49.4 kΩ/RG. For G = 10,000, RG = 4.94 Ω (1% tolerance recommended); for G = 1, Pins 1 and 8 remain unconnected. The AD620BRZ-R7's internal laser-trimmed resistors ensure <0.3% gain error at G = 100.

Can AD620BRZ-R7 operate from a single 5 V supply?

Yes, the AD620BRZ-R7 operates from single supplies as low as +4.6 V (±2.3 V equivalent) up to +36 V. In single-supply mode, the REF pin must be biased to mid-rail (e.g., 2.5 V) to center the output swing; the input common-mode range extends to −VS + 1.9 V to +VS − 1.4 V, allowing direct interface with 5 V bridge sensors when REF = 2.5 V. The AD620BRZ-R7 draws only 1.3 mA in this configuration.

What is the purpose of the REF pin on AD620BRZ-R7, and how should it be used?

The REF pin on AD620BRZ-R7 sets the DC level of the OUTPUT voltage. When grounded, OUTPUT swings symmetrically around 0 V; when tied to an external reference (e.g., ADC's VREF), it enables ratiometric measurements that reject supply variations. Driving REF with a low-impedance source (<20 kΩ) is mandatory - the AD620BRZ-R7's internal 20 kΩ resistor to REF limits sourcing capability, so buffer amplifiers are recommended for active biasing.

How does AD620BRZ-R7 compare to discrete 3-op-amp instrumentation amplifier designs?

The AD620BRZ-R7 replaces discrete three-op-amp IA designs with superior performance: 10× lower supply current (1.3 mA vs. 15 mA), 40% smaller PCB area (SOIC-8 vs. 3 × SOIC-8), and 50% lower total error (14,663 ppm vs. 28,134 ppm in a typical bridge application). Its monolithic construction ensures matched components, eliminating manual trimming and improving temperature tracking - all while maintaining identical functional behavior to legacy discrete topologies.

Is AD620BRZ-R7 suitable for driving ADC inputs directly, and what load conditions apply?

Yes, the AD620BRZ-R7 can drive SAR and delta-sigma ADC inputs directly. Its OUTPUT pin delivers ±13.6 V swing into 10 kΩ (at ±15 V supplies) and maintains 15 μs settling to 0.01% for 10 V steps - compatible with 16-bit ADCs sampling at ≤100 kSPS. For capacitive loads >100 pF, a series 10 Ω resistor is recommended to prevent peaking; the AD620BRZ-R7's output stage is not optimized for driving transmission lines or heavy capacitive loads without isolation.