Texas Instruments OPA4340UA

Overview

OPA4340UA from Texas Instruments is a quad rail-to-rail input/output CMOS operational amplifier optimized for single-supply, low-voltage operation (2.7 V to 5.5 V). It delivers 5.5 MHz gain-bandwidth, 6 V/µs slew rate, and output swing within 1 mV of rails under 100-kΩ load - enabling high-fidelity signal conditioning in A/D converter driver, audio, and data acquisition circuits.

For engineers reviewing the OPA4340UA datasheet, OPA4340UA pinout, OPA4340UA application, or OPA4340UA equivalent, key selection criteria include rail-to-rail input common-mode range extending 500 mV beyond supply rails, 750 µA per-channel quiescent current, THD+N of 0.0007% at 1 kHz, and guaranteed operation from –40°C to 85°C in SOIC-14 packaging.

Technical Context

The OPA4340UA uses a complementary CMOS input stage (N- and P-channel parallel pairs) to achieve rail-to-rail input operation, with seamless transition across a ~400 mV region near (V+) – 1.3 V where both pairs conduct. Laser trimming minimizes offset mismatch between input stages, preserving CMRR and PSRR outside the transition zone.

Its class AB output stage employs common-source transistors to deliver rail-to-rail output swing - maintaining >106 dB open-loop gain while driving loads down to 2 kΩ. The device is unity-gain stable and supports capacitive loads up to 1000 pF in G = +1 configuration without external compensation.

Key Specifications

Pinout & Package

OPA4340UA is packaged in a 14-pin SOIC (body size 8.65 mm × 3.91 mm), rated for operation from –40°C to 85°C. Thermal resistance R_θJA is 83.8°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad rail-to-rail operational amplifier applications.

Compared with OPA4340U, the OPA4340UA offers identical core performance but improved charged-device model ESD tolerance; versus TLV2464AIDR, it delivers 4× lower input offset, 3× lower THD+N, and guaranteed rail-to-rail input operation - making it essential for precision, low-noise, and single-supply-critical designs.

Availability

OPA4340UA is available at Aetrix Electronics and suitable for data acquisition systems, portable audio interfaces, industrial sensor modules, and medical instrumentation requiring stable component supply and long-term manufacturability.

Supply support for OPA4340UA 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 op-amps and signal chain solutions.

The OPA340 family - including OPA4340UA - was designed specifically for single-supply, rail-to-rail signal conditioning in space-constrained, low-power applications such as portable instrumentation and battery-operated DAQ systems.

FAQ

What is the maximum operating supply voltage for OPA4340UA?

The OPA4340UA supports an absolute maximum supply voltage of 5.5 V across V+ and V− pins. Its recommended operating range is 2.7 V to 5.5 V, with full specification compliance at 2.7 V to 5 V. Operation below 2.7 V may reduce open-loop gain and increase input offset drift; always verify performance at target voltage using the Electrical Characteristics table in the SBOS073C datasheet for OPA4340UA.

Does OPA4340UA support true rail-to-rail input with signals below ground?

Yes - the OPA4340UA features a rail-to-rail input stage that accepts common-mode voltages from –0.3 V to (V+) + 0.3 V. This allows direct interfacing with signals extending 500 mV below ground (e.g., AC-coupled sensor outputs or bipolar DACs), provided input current is limited to ≤10 mA via series resistance. The complementary N/P-channel input architecture enables this extended range without phase reversal or latch-up.

Can OPA4340UA drive a 600 Ω load while maintaining rail-to-rail output swing?

At 600 Ω, the OPA4340UA output swing degrades to approximately 4.8 VPP on a 5 V supply (per Figure 15 in SBOS073C), due to increased output stage voltage drop. While it can source/sink ±50 mA short-circuit current, full rail-to-rail swing (<10 mV from rails) is only guaranteed for RL ≥10 kΩ. For 600 Ω loads, expect ~200 mV minimum headroom - confirm actual swing using the Output Voltage Swing vs Output Current curve for your specific supply and temperature.

Is OPA4340UA pin-compatible with other packages of the same part number?

No - OPA4340UA specifically denotes the 14-pin SOIC (D package) variant. The quad OPA4340 is also offered in 16-pin SSOP (DBQ), but pinout differs significantly (e.g., NC pins at positions 8/9 in SOIC vs 8/9 in SSOP). Always consult the Pin Functions table for OPA4340 in SBOS073C: SOIC-14 and SSOP-16 have distinct pin mappings and thermal characteristics (R_θJA = 83.8°C/W vs 115.8°C/W), so they are not interchangeable without layout revision.

What is the typical input bias current of OPA4340UA, and how does it affect high-impedance sensor interfaces?

The OPA4340UA exhibits a typical input bias current of ±0.2 pA at 25°C, with a maximum of ±10 pA over temperature. At 25°C, this introduces <2 µV error across a 10 MΩ source impedance - negligible for most precision applications. However, at –40°C or +85°C, bias current rises to ±60 pA, producing up to 600 µV error. For ultra-high-Z sources (>100 MΩ), consider guarding or active guarding techniques, or select a FET-input op-amp with sub-100 fA bias current.