Texas Instruments OPA548T-1G3

Overview

OPA548T-1G3 from Texas Instruments is a high-voltage, high-current operational amplifier designed for precision power amplification in demanding industrial and test equipment. It delivers ±3-A continuous output current, supports ±4 V to ±30 V dual supplies (or 8–60 V single supply), features adjustable current limiting (0–5 A), thermal shutdown with status reporting via E/S pin, and operates across –40°C to +85°C ambient. It drives resistive, capacitive, and reactive loads in semiconductor test fixtures and programmable power supplies.

For engineers reviewing the OPA548T-1G3 datasheet, OPA548T-1G3 pinout, OPA548T-1G3 application, or OPA548T-1G3 equivalent, key selection criteria include output current capability, thermal protection behavior, enable/disable timing (1 µs disable / 3 µs enable), current limit adjustability via ILIM pin, and safe-operating-area compliance under transient load conditions.

Technical Context

The OPA548T-1G3 uses a PNP-input stage with negative input bias currents (–100 nA typ), enabling low-offset operation without bias current compensation when matched input resistances are used. Its high-current output stage employs temperature-compensated class A/B biasing to minimize crossover distortion while maintaining stability into reactive loads.

Current limiting is implemented via indirect sensing-applying a resistor between ILIM and V– sets output current from 0 A to 5 A using a low-level control signal (0–330 µA), avoiding series power-resistor losses. The E/S pin serves dual functions: logic-level output disable (reducing quiescent current to ±6 mA) and open-drain thermal shutdown status reporting (low = TJ > 160°C).

Key Specifications

Pinout & Package

OPA548T-1G3 is housed in a 7-lead TO-220 package with staggered leads (KVT variant), featuring an electrically isolated copper tab for direct heatsink mounting and optimized thermal resistance (R_θJA = 30.2°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with OPA548T-1G3, OPA547T offers reduced current capability and no integrated thermal status, while LM675T provides comparable current but omits adjustable limiting and status reporting - making OPA548T-1G3 uniquely suited for safety-aware, programmable power systems requiring autonomous fault response.

Availability

OPA548T-1G3 is available at Aetrix Electronics and suitable for semiconductor test fixtures, programmable power supplies, ultrasound transducer drivers, and lab instrumentation requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for OPA548T-1G3 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 power management ICs.

The OPA548T-1G3 belongs to TI's Precision Power Amplifier product line, engineered specifically for applications demanding robust high-current drive, integrated protection, and thermal intelligence in industrial test and medical equipment.

FAQ

What is the maximum continuous output current specification for the OPA548T-1G3?

The OPA548T-1G3 delivers ±3 A continuous output current into resistive loads at ambient temperatures up to +85°C, with derating required above that temperature per its thermal characteristics. Peak current capability reaches ±5 A for short durations, and the device includes internal thermal shutdown to protect against sustained overload conditions. This rating applies to both TO-220 (KVT) and DDPAK (KTW) packages when properly heatsinked.

How does the ILIM pin on the OPA548T-1G3 set the output current limit?

The ILIM pin on the OPA548T-1G3 accepts a current sink (0–330 µA) to set output current from 0 A to 5 A. Connecting a resistor R_CL between ILIM and V– implements this per the equation I_LIM = (15000)(4.75)/(13750 + R_CL). For example, a 14.7 kΩ resistor sets ~2.5 A. Leaving ILIM open disables output; tying it directly to V– sets maximum limit (~5 A). This indirect sensing avoids power loss in the main current path.

Can the OPA548T-1G3 operate from a single supply, and what is the input common-mode range in that configuration?

Yes, the OPA548T-1G3 operates from a single supply ranging from 8 V to 60 V. In single-supply mode, its input common-mode range extends below ground to (V–) – 0.1 V, allowing true rail-to-rail input capability relative to the negative rail. This enables direct interfacing with ground-referenced sensors or DACs without level-shifting circuitry, supporting applications like programmable voltage sources and analog input modules.

What functions does the E/S pin provide on the OPA548T-1G3, and how is it used?

The E/S (Enable/Status) pin on the OPA548T-1G3 provides two independent functions: pulling it to ≤ (V–) + 0.8 V disables the output stage (reducing quiescent current to ±6 mA), and monitoring its voltage reveals thermal shutdown status (drops to ~0.35 V above V– when TJ > 160°C). It supports both single- and dual-supply configurations and requires no external pull-up for basic operation - simplifying fault-aware system design.

What thermal protection features are built into the OPA548T-1G3, and how do they behave?

The OPA548T-1G3 integrates thermal shutdown that activates at ~160°C junction temperature and resets automatically at ~140°C. During shutdown, the E/S pin voltage drops to indicate fault condition, and output current ceases. Unlike latch-off devices, it recovers autonomously once cooled - preventing permanent lockout during transient overloads. This behavior is documented in the Electrical Characteristics table and verified across production lots per TI's SBOS070D datasheet revision.