Texas Instruments OPA336UJ

Overview

OPA336UJ from Texas Instruments is a single-supply, microPower CMOS operational amplifier optimized for battery-powered instrumentation. It delivers rail-to-rail output swing within 3 mV of the rails, 125 µV max input offset voltage, and ultra-low 20 µA quiescent current per amplifier-enabling precision signal conditioning in portable medical devices and photodiode pre-amplifiers.

For engineers reviewing the OPA336UJ datasheet, OPA336UJ pinout, OPA336UJ application, or OPA336UJ equivalent, key selection criteria include its 2.3 V to 5.5 V supply range, 1 pA input bias current, –40°C to +85°C temperature specification, SO-8 package compatibility, and verified rail-to-rail output performance under 100 kΩ load.

Technical Context

The OPA336UJ employs a CMOS input stage enabling 1 pA typical input bias current and 10¹³ Ω || 4 pF common-mode input impedance. Its unity-gain-stable architecture supports stable operation with capacitive loads up to 300 pF in unity-gain configuration, and up to 1000 pF when combined with a 100 Ω series feedback resistor.

It features an extended common-mode input range from (V–) –0.2 V to (V+) –1 V, allowing direct interface with sensors operating near ground in single-supply systems. The device maintains 115 dB open-loop gain and 90 dB CMRR over the full specified temperature range, ensuring consistent DC accuracy in low-drift integrators and high-impedance transducer interfaces.

Key Specifications

Pinout & Package

OPA336UJ is supplied in an SO-8 surface-mount package (package drawing D), measuring 4.9 mm × 3.9 mm × 1.75 mm, with standard JEDEC-compliant lead pitch (1.27 mm) and RoHS-compliant CU-NiPdAu finish (Level-2-260°C MSL rating).

Key Features

Applications

Equivalent & Alternatives

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

Compared with OPA336UJ, OPA340UA trades 11× higher power for 80× more bandwidth-ideal for signal chain stages needing AC response-but OPA336UJ remains superior for DC-precision, ultra-low-power, and ESD-robust (CDM-1000V) applications in portable diagnostics.

Availability

OPA336UJ is available at Aetrix Electronics and suitable for battery-powered instruments, photodiode pre-amplifiers, precision integrators, medical instruments, and portable test equipment requiring stable component supply across long production lifecycles.

Supply support for OPA336UJ 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, embedded processing, and connectivity solutions for industrial, automotive, and personal electronics markets.

The OPA336UJ belongs to TI's microAmplifier™ series, designed specifically for ultra-low-power, high-precision analog signal conditioning in portable and battery-operated instrumentation.

FAQ

What is the maximum capacitive load the OPA336UJ can drive without external compensation?

The OPA336UJ can drive up to 300 pF in unity-gain configuration without external compensation. This value is confirmed in the Applications Information section of the SBOS068C datasheet. For larger capacitive loads-such as those found in LCD bias networks or long cable interfaces-a 50 Ω to 100 Ω series resistor inside the feedback loop is recommended. The OPA336UJ's stability margin degrades predictably beyond this limit, and Figure 5 in the datasheet defines safe operating regions based on resistive load placement.

Does the OPA336UJ support true rail-to-rail input operation?

No, the OPA336UJ does not support rail-to-rail input. Its common-mode input voltage range extends from (V–) –0.2 V to (V+) –1 V, meaning the positive input cannot reach within 1 V of V+. However, inputs may exceed the supply rails by up to 0.3 V without damage or phase inversion, as shown in Figure 1 of the datasheet. This limited overvoltage tolerance supports robust interfacing with sensors whose outputs transiently overshoot the supply, but it is not a full rail-to-rail input stage.

What is the ESD rating for the OPA336UJ, and how does it differ from other OPA336 variants?

The OPA336UJ is rated for 1000 V Charged Device Model (CDM) ESD per the Absolute Maximum Ratings table. This is explicitly stated for "OPA336 NJ and UJ only" and distinguishes it from earlier OPA336N/U variants, which were tested only under HBM (500 V) and MM (100 V). The enhanced CDM rating reflects tighter process control and makes the OPA336UJ more suitable for automated SMT assembly lines where CDM events pose higher risk than HBM.

Can the OPA336UJ operate from a 2.1 V supply in production systems?

Yes, the OPA336UJ functions down to 2.1 V, as confirmed in the Applications Information section ("OPA336 series op amps can operate from a +2.1V to +5.5V single supply"). However, only the 2.3 V to 5.5 V range is fully specified across temperature and parametric limits. At 2.1 V, parameters such as GBW, slew rate, and output swing remain functional but are not guaranteed-making it viable for end-of-battery-life operation in consumer devices, though not for production-critical DC accuracy.

Is the SO-8 package of the OPA336UJ pin-compatible with dual or quad variants like OPA2336U or OPA4336EA?

No, the OPA336UJ (single-channel) SO-8 pinout is not pin-compatible with OPA2336U (dual) or OPA4336EA (quad). As shown in the package drawings, OPA336UJ uses pins 1, 4, and 5 as NC, while OPA2336U assigns those pins to second amplifier terminals. Substituting packages without schematic and layout revision will result in incorrect connections and functional failure. Pin compatibility exists only within the same channel count (e.g., OPA336UJ ↔ OPA336UA), not across family members.