Analog Devices Inc. OP297FSZ-REEL7

Overview

OP297FSZ-REEL7 from Analog Devices is a dual precision operational amplifier optimized for low-bias-current, high-accuracy signal conditioning in instrumentation and sensor interfaces. It delivers 50 μV max input offset voltage, 0.6 μV/°C max drift, 100 pA max input bias current at 25°C, 2000 V/mV min open-loop gain, and operates from ±2 V to ±20 V supplies - enabling stable microvolt-level amplification in strain gage bridges and thermocouple front-ends.

For engineers reviewing the OP297FSZ-REEL7 datasheet, OP297FSZ-REEL7 pinout, OP297FSZ-REEL7 application, or OP297FSZ-REEL7 equivalent, key selection criteria include guaranteed picoamp bias current over temperature, CMRR ≥120 dB, PSRR ≥120 dB, rail-to-rail input common-mode range (±13 V), and SOIC_N package compatibility with space-constrained PCB layouts.

Technical Context

The OP297FSZ-REEL7 employs a super-beta bipolar input stage with bias current cancellation, maintaining ≤450 pA input bias current across −40°C to +85°C - unlike FET-input op amps whose bias current doubles per 10°C rise. Its open-loop gain exceeds 2000 V/mV with <0.1 μV p-p 0.1 Hz–10 Hz noise, supporting high closed-loop accuracy in integrators and log amplifiers.

Designed for DC-critical applications, it achieves 120 dB minimum common-mode and power supply rejection, enabling stable operation in battery-powered systems where supply ripple and ground shifts would otherwise corrupt low-level signals. Input resistance is 500 GΩ common-mode and 30 MΩ differential, minimizing loading on high-impedance sources like photodiodes and piezoelectric sensors.

Key Specifications

Pinout & Package

OP297FSZ-REEL7 is housed in an 8-lead SOIC_N (R-8) package per JEDEC MS-012-AA, with 1.27 mm lead pitch, 5.00 mm × 4.00 mm body, and RoHS-compliant matte tin lead finish. The package supports automated pick-and-place and reflow soldering per IPC/JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with OP297FSZ-REEL7, OP2177ARZ-REEL7 trades bias current for lower offset and higher speed, while LTC1052CS8#TRPBF eliminates drift via auto-zeroing but adds switching artifacts - making OP297FSZ-REEL7 optimal for high-impedance, wide-temperature, low-noise DC amplification where simplicity and proven reliability are prioritized.

Availability

OP297FSZ-REEL7 is available at Aetrix Electronics and suitable for strain gage amplifiers, thermocouple signal conditioners, and photocurrent monitors requiring stable component supply across industrial, test & measurement, and medical device programs.

Supply support for OP297FSZ-REEL7 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 precision instrumentation, industrial automation, and communications markets since 1965.

The OP297 belongs to Analog Devices' precision op amp product line, engineered specifically for DC-critical applications demanding ultra-low bias current, low drift, and high open-loop gain - including sensor front-ends, integrators, and logarithmic converters.

FAQ

What is the maximum input bias current specification for OP297FSZ-REEL7 over temperature?

The OP297FSZ-REEL7 has a maximum input bias current of 450 pA across the full operating temperature range of −40°C to +85°C, as specified in Table 2 of the Rev. G datasheet. This is guaranteed for the S-Suffix (SOIC_N) grade and reflects its super-beta input stage with active bias cancellation - distinguishing it from conventional FET-input op amps that degrade significantly above 25°C.

Does OP297FSZ-REEL7 support single-supply operation?

Yes, OP297FSZ-REEL7 supports true single-supply operation down to +4 V total supply (e.g., V+ = +4 V, V− = 0 V), though its specified input common-mode and output swing ranges are optimized for split supplies. When used single-ended, the input common-mode range extends to within 1 V of either rail, and output swings to within 1 V of the rails with 10 kΩ load - enabling rail-to-rail input/output functionality in many configurations.

What is the recommended PCB layout practice to preserve OP297FSZ-REEL7's low-bias-current performance?

To preserve the OP297FSZ-REEL7's picoamp-level input bias current, Analog Devices recommends guard rings around both input traces, routed at the same potential as the input nodes (e.g., connected to the inverting input in noninverting configurations). Board surfaces must be cleaned thoroughly and conformally coated to prevent surface leakage, and high-impedance traces should avoid proximity to noisy signals or power planes - as even 100 pA leakage between adjacent traces can dominate input error.

How does OP297FSZ-REEL7 compare to the single-channel OP97 in terms of key parameters?

The OP297FSZ-REEL7 shares identical electrical specifications with the OP97 (single-channel version) - including 50 μV max offset, 100 pA max bias current at 25°C, and 2000 V/mV min open-loop gain - but integrates two independent amplifiers in one SOIC_N package. This provides board-space savings and matched thermal tracking for dual-path applications like instrumentation amplifiers or differential receivers, without compromising DC precision.

Is OP297FSZ-REEL7 suitable for use in logarithmic amplifier circuits?

Yes, OP297FSZ-REEL7 is explicitly recommended for logarithmic amplifiers due to its extremely low and stable input bias current (≤450 pA over temperature), which minimizes diode junction error and ensures accurate exponential transfer functions. Its low 0.6 μV/°C offset drift and high CMRR also reduce temperature-induced nonlinearity - making it ideal for precision log amps in optical power measurement and dynamic range compression circuits.