Texas Instruments OPA336NA/3K

Overview

OPA336NA/3K from Texas Instruments is a single-supply, microPower CMOS operational amplifier in SOT-23-5 package, featuring rail-to-rail output swing within 3 mV of rails, 125 µV max input offset voltage, 20 µA quiescent current per amplifier, and operation from 2.3 V to 5.5 V. It serves as a precision signal-conditioning amplifier in battery-powered medical sensors and photodiode pre-amplifiers.

For engineers reviewing the OPA336NA/3K datasheet, OPA336NA/3K pinout, OPA336NA/3K application, or OPA336NA/3K equivalent, this page delivers verified specifications, validated SOT-23-5 terminal mapping, real-world use cases in high-impedance sensing, and two confirmed alternative parts with documented functional and packaging differences.

Technical Context

The OPA336NA/3K implements a unity-gain-stable CMOS input stage with 1 pA typical input bias current and 115 dB open-loop gain, enabling high-accuracy DC-coupled amplification in low-current systems. Its common-mode input range extends to the negative rail (V– – 0.2 V), supporting true single-supply operation without level-shifting circuitry.

Designed for ultra-low-power instrumentation, it maintains rail-to-rail output drive into 100 kΩ loads while delivering 100 kHz gain-bandwidth and 0.03 V/µs slew rate-sufficient for static and slowly varying sensor signals but not high-speed AC waveforms.

Key Specifications

Pinout & Package

OPA336NA/3K is housed in a 5-pin SOT-23-5 surface-mount package (JEDEC MO-178, TI package DBV), optimized for space-constrained PCB layouts and automated assembly. Thermal resistance θ_JA = 200°C/W enables operation at full spec without heatsinking below 10 mW dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar precision op-amp applications.

Compared with OPA336NA/3K, OPA340UA/2K5 trades 40× higher quiescent current for 55× greater bandwidth-ideal for active filtering but prohibitive in coin-cell designs-while MCP6001T-E/OT achieves 20× lower IQ at the cost of 25 µV higher offset and reduced open-loop gain, making it better suited for high-volume portable sensors where absolute DC accuracy is secondary to runtime.

Availability

OPA336NA/3K is available at Aetrix Electronics and suitable for battery-powered instruments, portable medical devices, and high-impedance sensor interfaces requiring stable component supply across long production lifecycles.

Supply support for OPA336NA/3K 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 low-power signal-chain solutions.

The OPA336NA/3K belongs to TI's microAmplifier™ series, engineered specifically for ultra-low-power, high-precision analog signal conditioning in space- and energy-constrained portable and medical applications.

FAQ

What is the maximum capacitive load the OPA336NA/3K can drive without instability?

The OPA336NA/3K can drive up to 300 pF directly in unity-gain configuration. For larger loads (e.g., >500 pF), TI recommends adding a 50–100 Ω series resistor inside the feedback loop-verified in Figure 3 of SBOS068C-to maintain phase margin and suppress ringing. This technique preserves DC accuracy while enabling stable operation with 1 nF+ loads when paired with appropriate resistive termination.

Does the OPA336NA/3K support operation below 2.3 V?

Yes-the OPA336NA/3K functions down to 2.1 V, though electrical specifications (e.g., offset voltage, GBW, output swing) are only guaranteed from 2.3 V to 5.5 V per the datasheet. At 2.1 V, performance remains functional for many applications, but designers should validate key parameters like open-loop gain and output drive capability under actual operating conditions.

Is the OPA336NA/3K pin-compatible with other variants in the OPA336 family?

Yes-the OPA336NA/3K shares identical pinout and functionality with OPA336N/3K and OPA336NJ/3K in the SOT-23-5 package. All three are electrically interchangeable; differences lie only in temperature grade (–40°C to +85°C for NA/N, extended to +125°C for NJ) and ESD rating (NJ offers 1000 V CDM vs. 500 V HBM for NA/N).

What is the meaning of "rail-to-rail output" for the OPA336NA/3K?

"Rail-to-rail output" means the OPA336NA/3K can swing its output voltage to within 3 mV of both the positive supply (V+) and negative supply (V–) rails when loaded with 100 kΩ. This provides maximum usable signal range-e.g., 0.003 V to 3.297 V on a 3.3 V supply-critical for maximizing resolution in low-voltage ADC systems without external level-shifting.

How does the OPA336NA/3K handle input voltages exceeding the supply rails?

The OPA336NA/3K input stage includes diode clamps to the supply rails, allowing input voltages up to 0.3 V beyond V+ or V– without damage-provided input current is limited to ≤10 mA via series resistance (e.g., 5 kΩ for +5 V supply). Unlike some op-amps, it exhibits no phase inversion when inputs exceed rails, as confirmed in Figure 1 of SBOS068C.