Texas Instruments OPA2171AIDCUT

Overview

OPA2171AIDCUT from Texas Instruments is a dual-channel, rail-to-rail output, general-purpose operational amplifier in a 5-pin SOT-553 package. It operates from 2.7V to 36V single supply (±1.35V to ±18V), delivers 3MHz gain bandwidth, 14nV/√Hz input voltage noise, ±0.3µV/°C typical offset drift, and 475µA per amplifier quiescent current. It is used in precision transducer amplification, bridge sensing, and battery-powered instrumentation.

For engineers reviewing the OPA2171AIDCUT datasheet, OPA2171AIDCUT pinout, OPA2171AIDCUT application, or OPA2171AIDCUT equivalent, key selection criteria include its rail-to-rail output swing, 100mV-below-negative-rail input capability, phase-reversal immunity, low 8pA input bias current, and stable operation with up to 300pF capacitive loads - all critical for high-accuracy signal conditioning in industrial and portable systems.

Technical Context

The OPA2171AIDCUT implements a proprietary CMOS input stage with RFI filtering and internal phase-reversal protection, enabling reliable operation when inputs exceed the common-mode range without output inversion. Its architecture supports full rail-to-rail output swing while maintaining 120dB typical CMRR and 130dB open-loop gain across –40°C to +125°C.

It features a wide common-mode input range extending 100mV below V– and within 2V of V+, with specified performance maintained over 2.7V–36V supply and ±0.3µV/°C drift - making it suitable for unregulated or widely varying supply rails in embedded sensor front-ends and power module monitoring circuits.

Key Specifications

Pinout & Package

SOT-553 (DRL) package: 1.6mm × 1.6mm footprint, 0.5mm pitch, ultra-miniature 5-pin surface-mount package optimized for space-constrained PCBs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with OPA2171AIDCUT, OPA2172AIDCUT trades quiescent current and supply flexibility for speed, while LMV722MMX/NOPB sacrifices bandwidth and noise performance to achieve one-quarter the power consumption - making OPA2171AIDCUT the balanced choice for precision, low-noise, wide-supply industrial signal chains.

Availability

OPA2171AIDCUT is available at Aetrix Electronics and suitable for transducer amplification, bridge sensor conditioning, and battery-powered instrumentation requiring stable component supply across extended temperature ranges and diverse voltage rails.

Supply support for OPA2171AIDCUT 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

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of expertise in precision amplifiers and industrial-grade IC design.

The OPAx171 family was engineered for general-purpose, high-accuracy signal conditioning in harsh environments - targeting applications demanding low drift, wide supply range, and robust EMI immunity without sacrificing size or power efficiency.

FAQ

What is the maximum capacitive load the OPA2171AIDCUT can drive without instability?

The OPA2171AIDCUT is characterized for stable operation with capacitive loads up to 300pF, as confirmed in TI's SBOS516H datasheet Section 5.9 and Figure 5-23. This specification applies under standard test conditions (VS = ±18V, RL = 10kΩ). For loads exceeding 300pF, a series isolation resistor (e.g., 50Ω) between OUT and the load is recommended to maintain phase margin. The OPA2171AIDCUT does not require external compensation networks for typical ADC input or cable-drive scenarios.

Does the OPA2171AIDCUT support true rail-to-rail input operation?

The OPA2171AIDCUT supports rail-to-rail *output*, but its input common-mode range extends only to V– – 0.1V and V+ – 2V for full-specified performance. It can accept inputs up to V+ + 0.1V (beyond the positive rail), but with degraded parameters (e.g., increased offset, reduced CMRR) as detailed in Table 6-1 of the SBOS516H datasheet. Therefore, OPA2171AIDCUT is not a true rail-to-rail input amplifier - it is optimized for high-precision applications where input signals remain within the guaranteed linear range.

What is the typical input bias current of the OPA2171AIDCUT, and how does it affect high-impedance sensor interfaces?

The OPA2171AIDCUT has a typical input bias current of ±8pA, with a maximum of ±15pA at 25°C and ±3.5nA over –40°C to +125°C. At 8pA, it introduces <0.8mV error across a 100MΩ source impedance - making it suitable for pH electrodes, piezoelectric sensors, and photodiode transimpedance stages where leakage-induced offset must be minimized. Its CMOS input structure ensures this low bias current remains stable across temperature and supply voltage.

Can the OPA2171AIDCUT operate from a single 3.3V supply?

Yes, the OPA2171AIDCUT is fully specified and functional from a single 3.3V supply (2.7V minimum), as stated in Section 5.3 "Recommended Operating Conditions" of the SBOS516H datasheet. At 3.3V, it maintains rail-to-rail output swing (within ~30mV of each rail), 3MHz gain bandwidth, and 14nV/√Hz noise density. Its input common-mode range spans from –0.1V to 1.3V, allowing direct interfacing with 0–3.3V sensor outputs or reference buffers without level-shifting circuitry.

How does the phase-reversal protection in the OPA2171AIDCUT improve system reliability?

The OPA2171AIDCUT incorporates internal circuitry that prevents output phase reversal when input signals exceed the common-mode voltage range - a failure mode common in many op-amps that causes catastrophic control loop errors. Instead of inverting, the output saturates predictably toward the appropriate supply rail. This behavior, verified in Figure 5-25 and Section 6.3.3 of SBOS516H, enhances safety in applications like motor current sensing or overvoltage-protected sensor inputs where transient excursions are possible.