Texas Instruments OPA2704UA

Overview

OPA2704UA from Texas Instruments is a dual-channel, rail-to-rail input/output CMOS operational amplifier optimized for non-inverting gains ≥5. It delivers 3MHz gain-bandwidth product, 3V/µs slew rate, 160µA quiescent current per amplifier, ±160µV input offset voltage, and operates from ±2V to ±6V dual supplies (or 4V–12V single supply). It is used in precision sensor signal conditioning within automotive security systems.

For engineers reviewing the OPA2704UA datasheet, OPA2704UA pinout, OPA2704UA application, or OPA2704UA equivalent, key selection criteria include guaranteed stability at G ≥ 5, rail-to-rail swing with ≤75mV output voltage drop into 20kΩ, low 1pA input bias current, and SOIC-8 packaging compatible with industrial temperature range (–40°C to +85°C).

Technical Context

The OPA2704UA employs complementary differential input pairs enabling rail-to-rail common-mode input range extending 300mV beyond supply rails, and a Class AB output stage achieving rail-to-rail output swing within 40mV of rails under light load. Its internal compensation is optimized for closed-loop gains of 5 or greater, distinguishing it from the unity-gain-stable OPA2703 series.

It features full-scale CMRR of 90dB at ±5V supplies, PSRR of 100dB, and open-loop gain >100dB into 20kΩ loads - all specified over –40°C to +85°C. Input voltage noise is 45nV/√Hz at 1kHz, and total harmonic distortion + noise is 0.025% at 1kHz with G = +5.

Key Specifications

Pinout & Package

OPA2704UA is housed in an 8-pin SOIC (SO-8) surface-mount package with standard JEDEC MS-012AC footprint, 1.27mm pitch, and 150°C/W junction-to-ambient thermal resistance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-rail-to-rail op-amp applications.

Compared with OPA2704EA, the OPA2704UA offers identical AC/DC performance in a larger, more manufacturable SOIC-8 package; compared with OPA2333AIDR, it trades ultra-low drift for 8.6× higher bandwidth and 4.7× lower quiescent current - making it optimal for cost-sensitive, medium-speed industrial signal paths.

Availability

OPA2704UA is available at Aetrix Electronics and suitable for automotive sensor interfaces, portable data acquisition front-ends, and dual-supply reference buffering requiring stable component supply across industrial temperature ranges.

Supply support for OPA2704UA 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 heritage in precision op-amps and signal chain solutions.

The OPA703/704 family - including OPA2704UA - was designed specifically for rail-to-rail, low-power, medium-bandwidth signal conditioning in automotive, industrial, and portable equipment where supply headroom is constrained.

FAQ

What is the minimum recommended gain for stable operation of the OPA2704UA?

The OPA2704UA is internally compensated for stable operation only at closed-loop gains of +5 or greater. Using it at unity gain or G = +2 risks phase margin degradation and potential oscillation, as confirmed by TI's SBOS180A datasheet Figure 6 and Applications Information section. Always verify stability with capacitive load testing when using OPA2704UA in G ≥ 5 configurations.

Does the OPA2704UA support single-supply operation?

Yes, the OPA2704UA supports single-supply operation from 4V to 12V, with rail-to-rail input and output swing enabling full dynamic range utilization. Its input common-mode range extends 300mV beyond the negative rail (e.g., down to –0.3V when V– = 0V), and output swings to within 40mV of either rail under light load - making it suitable for 3.3V or 5V microcontroller-based systems.

What is the maximum capacitive load the OPA2704UA can drive reliably?

The OPA2704UA can reliably drive up to 1000pF of pure capacitive load when configured at G ≥ 5, as documented in the "Capacitive Load and Stability" section of SBOS180A. At unity gain, stability degrades significantly above ~100pF; however, inserting a 10Ω–20Ω series resistor in the feedback path (Figure 5) restores robustness for larger loads while preserving DC accuracy.

How does the OPA2704UA's input stage handle overvoltage conditions?

The OPA2704UA input terminals are protected by ESD diodes clamped to the supply rails. Inputs exceeding V+ or falling below V– by more than ~300mV will conduct, but remain safe if current is limited to ≤10mA - typically achieved with a series input resistor. Unlike older architectures, the OPA2704UA exhibits no phase inversion when inputs exceed rails under current-limited conditions, as verified in Figure 4 of SBOS180A.

Is the OPA2704UA pin-compatible with the OPA2703UA?

Yes, the OPA2704UA and OPA2703UA share identical SOIC-8 pinouts and package footprints, enabling direct PCB replacement. However, they differ critically in internal compensation: OPA2703UA is unity-gain stable (1MHz GBW, 0.6V/µs), while OPA2704UA is optimized for G ≥ 5 (3MHz GBW, 3V/µs). Swapping them requires verifying gain configuration and stability margins in the target circuit.