Texas Instruments OPA726AIDGKTG4

Overview

OPA726AIDGKTG4 from Texas Instruments is a single-channel, rail-to-rail output operational amplifier with shutdown control, designed for high-precision, high-speed signal conditioning in 16-bit data acquisition systems. It delivers 20MHz gain-bandwidth, 30V/µs slew rate, 6nV/√Hz input voltage noise at 100kHz, rail-to-rail output swing within 150mV of supply rails, and operates from ±2V to ±6V or +4V to +12V supplies.

For engineers reviewing the OPA726AIDGKTG4 datasheet, OPA726AIDGKTG4 pinout, OPA726AIDGKTG4 application, or OPA726AIDGKTG4 equivalent, key selection criteria include fast 16-bit settling time (450ns to 0.01%), low THD+N (0.0003% at 1kHz), shutdown current of 6µA/ch, and compatibility with transimpedance, ADC buffer, and active filter topologies requiring CMOS input stage and wide common-mode range including ground.

Technical Context

The OPA726AIDGKTG4 uses a proprietary 12V analog CMOS process enabling simultaneous high bandwidth (20MHz GBW) and ultra-low input bias current (<200pA), making it suitable for photodiode transimpedance amplifiers where leakage and noise critically impact dynamic range. Its rail-to-rail output stage employs a class AB common-source architecture delivering 150mV rail margin into 100kΩ loads while maintaining >110dB open-loop gain.

Shutdown functionality is implemented via an enable pin referenced to DGND, requiring logic-high > VDGND + 2V to activate and < VDGND + 0.8V to disable - supporting direct interface with standard CMOS logic in dual-supply configurations without level-shifting. Input common-mode range extends from V− to (V+) − 2V, with CMRR >94dB maintained across most of that span.

Key Specifications

Pinout & Package

OPA726AIDGKTG4 is packaged in an 8-pin MSOP (DGK) with exposed thermal pad, optimized for space-constrained PCB layouts and thermal performance in industrial and optical modules.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed, low-noise op amp applications.

Compared with OPA725AIDGKT and OPA380AIDGKT, the OPA726AIDGKTG4 uniquely combines shutdown control, rail-to-rail output, and 6nV/√Hz noise in a single MSOP-8 package - making it optimal for portable, precision, and optical applications demanding both low power and high fidelity.

Availability

OPA726AIDGKTG4 is available at Aetrix Electronics and suitable for optical networking, precision data acquisition, portable audio, and industrial process control applications requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for OPA726AIDGKTG4 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 high-performance op amps and precision signal chain solutions.

The OPA726AIDGKTG4 belongs to TI's OPA725/726 series of 12V CMOS op amps, engineered specifically for driving 16-bit ADCs and transimpedance amplification in optical and test equipment where speed, noise, and rail-to-rail operation are simultaneously critical.

FAQ

What is the maximum operating supply voltage for the OPA726AIDGKTG4?

The OPA726AIDGKTG4 has an absolute maximum supply voltage rating of +13.2V. It is specified for continuous operation from +4V to +12V (single supply) or ±2V to ±6V (dual supply). Operation above +12V or below ±2V is outside the guaranteed specification range and may cause parametric degradation or reliability risk.

Does the OPA726AIDGKTG4 support rail-to-rail input operation?

No, the OPA726AIDGKTG4 does not support rail-to-rail input. Its input common-mode voltage range extends from V− to (V+) − 2V, meaning it accepts signals down to the negative rail but cannot handle inputs within 2V of the positive rail. However, it does provide rail-to-rail output swing within 150mV of both supply rails under light loads.

How does the Enable and DGND pin configuration work on the OPA726AIDGKTG4?

The OPA726AIDGKTG4 uses a referenced enable scheme: the Enable pin (Pin 1) is compared against the DGND pin (Pin 5). The amplifier activates when Enable > DGND + 2V and shuts down when Enable < DGND + 0.8V. In dual-supply designs, DGND is typically connected to system ground, allowing standard 0V/5V logic to directly control shutdown without level shifters.

Can the OPA726AIDGKTG4 drive capacitive loads, and what is the recommended compensation?

Yes, the OPA726AIDGKTG4 can drive moderate capacitive loads. For unity-gain stable operation with >100pF loads, TI recommends inserting a 10Ω–20Ω resistor in series with the output inside the feedback loop. This preserves DC accuracy while suppressing ringing and overshoot, as verified in typical characteristics curves showing reduced small-signal overshoot with added series resistance.

What is the typical input bias current of the OPA726AIDGKTG4, and why is it important?

The typical input bias current of the OPA726AIDGKTG4 is 30pA, with a maximum of 200pA over temperature. This ultra-low bias current is essential in high-impedance applications such as photodiode transimpedance amplifiers and precision integrators, where even nanoamp-level leakage introduces significant offset error and drift - especially when paired with large feedback resistors (e.g., 10MΩ).