Texas Instruments OPA336U

Overview

OPA336U from Texas Instruments is a single-supply, microPower CMOS operational amplifier designed for battery-powered instrumentation and portable devices. It features rail-to-rail output swing within 3mV of the rails, 20µA quiescent current per amplifier, 125µV max input offset voltage, and operates from 2.3V to 5.5V supply. Its role is precision signal conditioning in low-power, high-impedance sensor interfaces such as photodiode pre-amplifiers.

For engineers reviewing the OPA336U datasheet, OPA336U pinout, OPA336U application, or OPA336U equivalent, key selection criteria include ultra-low IQ (20µA), rail-to-rail output capability under 100kΩ load, 1pA input bias current, 115dB open-loop gain, and SO-8 package compatibility with legacy PCB layouts requiring stable, low-drift amplification at sub-1V headroom.

Technical Context

The OPA336U implements a CMOS input stage with input common-mode range extending to the negative rail (V–) –0.2V, enabling true single-supply operation. Its unity-gain-stable architecture delivers 100kHz gain-bandwidth and 0.03V/µs slew rate, optimized for DC-coupled, low-frequency precision applications rather than high-speed signal paths.

It integrates ESD protection rated at 500V HBM and features internal reverse-battery protection. The device maintains specified performance across –40°C to +85°C, with extended operation from –55°C to +125°C, and exhibits <±1.5µV/°C offset drift over temperature.

Key Specifications

Pinout & Package

OPA336U is packaged in an industry-standard SOIC-8 surface-mount package (Package Drawing D), with 1.27mm lead pitch and JEDEC MS-012AC compliance. Thermal resistance θ_JA is 150°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with OPA336U, OPA340UA offers 55× more bandwidth at 25× higher quiescent current, while MCP6001T-I/OT reduces IQ by 20× but sacrifices 12× offset voltage accuracy - making OPA336U the optimal balance for portable precision analog systems needing sub-130µV offset and <25µA consumption.

Availability

OPA336U is available at Aetrix Electronics and suitable for battery-powered instruments, portable medical devices, and high-impedance sensor interfaces requiring stable component supply across industrial and healthcare OEM programs.

Supply support for OPA336U 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-amp design and manufacturing reliability.

The OPA336U belongs to TI's microAmplifier™ series, engineered specifically for ultra-low-power, single-supply precision signal conditioning in portable and battery-operated instrumentation.

FAQ

What is the minimum operating supply voltage for the OPA336U?

The OPA336U operates down to 2.1V, though it is fully specified from 2.3V to 5.5V. At 2.1V, key parameters including output swing, offset voltage, and gain remain functional but may fall outside guaranteed limits. For production designs requiring guaranteed performance, use ≥2.3V supply per the datasheet's specified range. The OPA336U maintains rail-to-rail output capability even at this low voltage, supporting energy-harvesting and ultra-low-power applications.

Does the OPA336U support rail-to-rail input common-mode range?

No - the OPA336U supports rail-to-rail *output*, but its input common-mode range extends from (V–) –0.2V to (V+) –1V. This means the non-inverting input can accept signals down to 0.2V below ground (enabling true single-supply operation), but cannot reach within 1V of the positive rail. For example, with V+ = 5V and V– = 0V, valid input voltages span –0.2V to +4.0V. Exceeding this range risks increased bias current or phase inversion, though absolute maximum ratings allow transient excursions to ±0.3V beyond rails.

Can the OPA336U drive capacitive loads, and what is the recommended approach?

Yes - the OPA336U can drive capacitive loads up to ~300pF in unity-gain configuration without external compensation. For larger loads (e.g., >500pF), TI recommends inserting a 50Ω–100Ω resistor inside the feedback loop (between output and inverting input) to improve phase margin and suppress ringing. This technique preserves DC accuracy while enhancing stability. With RL = 25kΩ, the OPA336U remains stable driving >1000pF when configured with appropriate gain and feedback network design.

Is the OPA336U pin-compatible with other members of the OPA336 family?

No - the OPA336U (SO-8) is not pin-compatible with the SOT-23-5 variant (OPA336N/NA/NJ), which has only five pins and different pin assignments. While both share identical electrical specifications, the SO-8 version includes two NC pins and uses a different physical layout. Designers migrating from SOT-23-5 must revise PCB layout and cannot perform drop-in replacement. However, the SO-8 footprint matches industry-standard op-amp footprints, easing integration into existing SOIC-based designs.

What is the thermal performance of the OPA336U in SO-8 package?

The OPA336U in SO-8 package has a junction-to-ambient thermal resistance (θ_JA) of 150°C/W under standard JEDEC test conditions (2squares, 1oz copper). This allows safe operation up to +85°C ambient at full 20µA quiescent current, with junction temperature remaining well below the 150°C absolute maximum. For extended-temperature applications (–55°C to +125°C), derating is not required at typical operating currents, as self-heating remains negligible (<0.003°C rise). PCB layout with thermal vias to inner ground planes further improves thermal performance in compact enclosures.