Texas Instruments OPA4171AIPW

Overview

OPA4171AIPW from Texas Instruments is a quad-channel, rail-to-rail output, general-purpose operational amplifier optimized for single-supply operation from 2.7V to 36V (±1.35V to ±18V), featuring 3MHz gain bandwidth, 14nV/√Hz input voltage noise at 1kHz, ±0.3µV/°C typical offset drift, and 475µA per amplifier quiescent current. It serves precision signal conditioning in industrial sensor interfaces and battery-powered instrumentation.

For engineers reviewing the OPA4171AIPW datasheet, OPA4171AIPW pinout, OPA4171AIPW application, or OPA4171AIPW equivalent, key selection criteria include its rail-to-rail output swing (within 30mV of rails at 5V), full common-mode input range extending 100mV beyond V– and within 2V of V+, phase-reversal immunity, and stable operation with up to 300pF capacitive loads.

Technical Context

The OPA4171AIPW implements a PCH/NCH complementary input stage with internal phase-reversal protection, enabling robust operation when inputs exceed the linear common-mode range without output polarity inversion. Its open-loop gain exceeds 110dB over –40°C to +125°C, and CMRR reaches 120dB at ±18V supply.

It supports true single-supply operation with input voltage range from (V–) – 0.1V to (V+) – 2V under normal conditions, and full rail-to-rail input capability up to (V+) + 0.1V (with reduced performance within 2V of V+). The device is specified across the full industrial temperature range and drives capacitive loads up to 300pF without external compensation.

Key Specifications

Pinout & Package

TSSOP-14 package (5.0mm × 6.4mm), thermally enhanced for quad op-amp density in compact industrial PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with OPA4182AIPW, OPA4171AIPW trades ultra-low drift for higher bandwidth and lower power; compared with LM324APW, it delivers superior noise, CMRR, and fault tolerance at modest cost premium-making it optimal for next-generation industrial sensor nodes.

Availability

OPA4171AIPW is available at Aetrix Electronics and suitable for transducer amplification, bridge sensing, temperature measurement, and battery-powered instrumentation requiring stable component supply across extended temperature and voltage ranges.

Supply support for OPA4171AIPW 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 delivering analog and embedded processing solutions for industrial, automotive, and personal electronics markets.

The OPAx171 family was designed for general-purpose precision amplification in harsh environments-emphasizing wide supply range, phase-reversal immunity, and thermal stability from –40°C to +125°C.

FAQ

What is the maximum capacitive load the OPA4171AIPW can drive without oscillation?

The OPA4171AIPW is stable driving capacitive loads up to 300pF into a 10kΩ load, as verified in TI's SBOS516H datasheet Section 5.9 and Figure 5-23. This eliminates the need for series isolation resistors in many capacitive-sensor applications. For loads exceeding 300pF, a small series resistor (e.g., 50Ω) at the output restores phase margin. The OPA4171AIPW's internal compensation is optimized for this behavior across its full 2.7V–36V supply range.

Does the OPA4171AIPW support true rail-to-rail input operation?

The OPA4171AIPW supports rail-to-rail input operation with limitations: its normal common-mode range extends from (V–) – 0.1V to (V+) – 2V. It can accept inputs up to (V+) + 0.1V, but performance degrades-offset voltage increases to 7mV, CMRR drops to 65dB, and GBW falls to 0.7MHz-per Table 6-1 in the datasheet. For full-spec operation, keep inputs within the (V–) – 0.1V to (V+) – 2V window.

What is the typical input bias current of the OPA4171AIPW, and how does it vary with temperature?

The OPA4171AIPW has a typical input bias current of ±8pA at 25°C, with a maximum of ±15pA over temperature. At –40°C to +125°C, bias current remains below ±3.5nA, as confirmed in Section 5.7 Electrical Characteristics. This ultra-low IB enables high-impedance sensor interfacing (e.g., pH electrodes, photodiodes) without significant error, and its minimal temperature coefficient preserves accuracy across industrial operating ranges.

Can the OPA4171AIPW be used in single-supply 3.3V systems?

Yes, the OPA4171AIPW is fully specified down to 2.7V supply, making it compatible with 3.3V single-supply systems. At 3.3V, it maintains rail-to-rail output swing (within 30mV of rails), 3MHz GBP, and 14nV/√Hz noise. Input common-mode range spans –0.1V to 1.3V, allowing direct interface with 0–3.3V sensor outputs. Its 475µA per amplifier quiescent current also ensures low power consumption in battery-backed 3.3V applications.

How does the OPA4171AIPW handle input overvoltage conditions that cause phase reversal in other op-amps?

The OPA4171AIPW incorporates internal phase-reversal protection circuitry that prevents output polarity inversion when inputs exceed the linear common-mode range. Instead of reversing, the output saturates cleanly into the appropriate rail-as demonstrated in Figure 6-1 (No Phase Reversal) of the SBOS516H datasheet. This behavior eliminates latch-up risk and system instability in fault conditions such as sensor disconnect or ESD transients, distinguishing it from standard op-amps like LM324.