Texas Instruments OPA313IDCKT

Overview

OPA313IDCKT from Texas Instruments is a single-channel, rail-to-rail input/output CMOS operational amplifier optimized for micro-power, low-noise, precision signal conditioning in battery-powered systems. It delivers 1-MHz gain bandwidth, 50 µA quiescent current per channel, 25 nV/√Hz input voltage noise at 1 kHz, 0.5 mV typical offset voltage, and operates from 1.8 V to 5.5 V - enabling use in portable medical sensors and loop-powered industrial transmitters.

For engineers reviewing the OPA313IDCKT datasheet, OPA313IDCKT pinout, OPA313IDCKT application, or OPA313IDCKT equivalent, this page provides verified electrical specifications, SC70-5 package details, real-world sensor interface use cases, and validated alternative parts for design flexibility under low-voltage, low-power constraints.

Technical Context

The OPA313IDCKT employs a complementary differential input stage (N- and P-channel pairs) enabling true rail-to-rail common-mode input range extending 200 mV beyond both supply rails - critical for single-supply operation down to +1.8 V. Its class AB output stage drives loads ≤10 kΩ while maintaining rail-to-rail swing.

Internal RF/EMI filtering (–3 dB at ~35 MHz) suppresses high-frequency interference rectification at inputs, and unity-gain stability supports direct connection to ADC drivers without external compensation. No phase reversal occurs under overdrive, and ESD protection meets 4-kV HBM.

Key Specifications

Pinout & Package

OPA313IDCKT is housed in a 5-pin SC70 package (DCK), measuring 2.0 mm × 1.25 mm × 0.9 mm, with exposed thermal pad connected to V– for enhanced thermal performance in space-constrained PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with OPA313IDCKT, OPA316IDCKT offers higher bandwidth at increased quiescent current, while MCP6001UT-E/OT provides lower cost but sacrifices EMI robustness and DC accuracy - making OPA313IDCKT optimal for precision, low-power, noise-immune applications.

Availability

OPA313IDCKT is available at Aetrix Electronics and suitable for battery-powered instruments, sensor signal conditioning, and wireless sensors requiring stable component supply with guaranteed long-term manufacturability.

Supply support for OPA313IDCKT 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 OPA313IDCKT belongs to TI's Precision Value Line op amp series - engineered specifically for cost-sensitive, low-power applications demanding rail-to-rail operation, low noise, and extended temperature reliability without sacrificing DC accuracy.

FAQ

What is the maximum capacitive load the OPA313IDCKT can drive while remaining stable?

The OPA313IDCKT is unity-gain stable with capacitive loads up to 150 pF, as confirmed in the datasheet's Phase Margin vs Capacitive Load plot (Figure 21). Driving larger loads requires isolation resistance or external compensation. This capability simplifies direct connection to ADC input capacitors and long PCB traces without added components - a key advantage in compact sensor modules where board space is constrained. The OPA313IDCKT maintains ≥65° phase margin under these conditions.

Does the OPA313IDCKT support true rail-to-rail input at 1.8-V supply?

Yes, the OPA313IDCKT supports rail-to-rail input at 1.8 V: its common-mode input range extends from (V–) – 0.2 V to (V+) + 0.2 V, meaning it accepts signals from –0.2 V to +2.0 V when powered from 1.8 V. This is explicitly verified in the Electrical Characteristics table for +1.8 V operation. The OPA313IDCKT achieves this via complementary N- and P-channel input stages, enabling accurate sensing of signals near ground or near the positive rail - critical for single-supply battery monitoring and low-voltage sensor interfaces.

What is the thermal performance of the OPA313IDCKT in the SC70-5 (DCK) package?

The OPA313IDCKT in SC70-5 (DCK) package has a junction-to-ambient thermal resistance (θJA) of 281.4°C/W and junction-to-board (θJB) of 59.6°C/W, per TI's thermal metrics report. To achieve reliable operation at full 125°C ambient, PCB layout must include a soldered thermal pad connected to a solid ground plane. Without thermal pad connection, power dissipation is limited to ~15 mW before exceeding 150°C junction temperature. The OPA313IDCKT's low 50 µA IQ inherently limits self-heating, making it well-suited for thermally isolated portable applications.

How does the internal EMI filter in the OPA313IDCKT improve system-level robustness?

The OPA313IDCKT integrates an internal low-pass filter (–3 dB at ~35 MHz) on both inputs to suppress electromagnetic interference rectification - a known cause of DC offset shifts in RF-rich environments. Measured EMIRR IN+ exceeds 100 dB at 900 MHz, significantly outperforming unfiltered op amps. This eliminates the need for external RC filters in wireless sensor nodes, wearables, and industrial gateways, preserving signal bandwidth while rejecting GSM, Bluetooth, and Wi-Fi band noise. The OPA313IDCKT's EMI immunity is validated per TI's standardized test methodology, not estimated.

Can the OPA313IDCKT be used in a single-supply photodiode transimpedance configuration?

Yes, the OPA313IDCKT is suitable for single-supply photodiode TIA applications due to its rail-to-rail input (accepting 0 V bias), low input bias current (0.2 pA typ), and low input capacitance (1 pF differential). However, the photodiode cathode must connect to V+ to reverse-bias it, and the output swings from near V– to within 75 mV of V+. For 3.3-V operation, this yields ~3.225 V max output swing. Stability requires careful layout and optional feedback capacitor (e.g., 0.3–1 pF) to compensate photodiode junction capacitance. The OPA313IDCKT's low noise and high PSRR further enhance weak-light signal recovery.