Texas Instruments OPA544TG3

Overview

OPA544TG3 from Texas Instruments (formerly Burr-Brown) is a high-voltage, high-current operational amplifier designed for direct drive of power loads including motors, actuators, and magnetic deflection coils. It delivers ≥2A continuous output current, operates from ±10V to ±35V supplies, and features 8V/µs slew rate, FET-input bias current ≤100pA, and thermal shutdown protection. It is used in programmable power supplies and servo amplifiers requiring robust output stage performance.

For engineers reviewing the OPA544TG3 datasheet, OPA544TG3 pinout, OPA544TG3 application, or OPA544TG3 equivalent, key selection criteria include safe operating area (SOA) compliance at elevated junction temperatures, output voltage swing under 2A load, thermal resistance (θ_JA = 65°C/W without heatsink), and compatibility with unbalanced supply configurations up to 70V total.

Technical Context

The OPA544TG3 integrates a high-impedance FET input stage with a monolithic high-power bipolar output stage capable of sourcing/sinking up to 2A continuously. Its internal current limit (~4A at 25°C, decreasing with temperature) and thermal shutdown (triggering at ~155°C) operate independently to protect against overload and overheating.

It supports non-inverting, inverting, and differential configurations with gain-bandwidth product of 1.4MHz (RL = 15Ω) and open-loop gain ≥90dB. Input common-mode range extends to within 4–6V of either rail, and output swing is specified as (V+) –4.4V / (V–) +3.8V at 2A load.

Key Specifications

Pinout & Package

The OPA544TG3 is supplied in a 5-lead TO-220 package (KC outline) with copper tab electrically connected to the V– pin for direct heatsink mounting and low thermal resistance (θ_JC = 2.7°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage, high-current op amp applications.

Compared with OPA547T and LM675T, the OPA544TG3 provides the optimal balance of guaranteed 2A continuous output, integrated thermal shutdown, and FET-input precision - making it preferred for servo, actuator, and programmable supply designs requiring reliability without external protection circuitry.

Availability

OPA544TG3 is available at Aetrix Electronics and suitable for motor driver, programmable power supply, and servo amplifier applications requiring stable component supply, long-term industrial lifecycle support, and traceable sourcing from authorized channels.

Supply support for OPA544TG3 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 (TI) is a global semiconductor leader specializing in analog, embedded processing, and power management technologies, with deep heritage in precision amplifiers dating to Burr-Brown acquisition in 2000.

The OPA544TG3 belongs to TI's high-power operational amplifier product line, engineered specifically for industrial motion control, programmable power, and high-fidelity analog output stages where output current, thermal resilience, and protection integration are primary design requirements.

FAQ

What is the maximum continuous output current specification for the OPA544TG3?

The OPA544TG3 is specified for ≥2A continuous output current into resistive loads at TCASE = +25°C with adequate heatsinking. Its safe operating area (SOA) curve confirms this rating across voltage drops up to |VS – VO| = 5V. At higher voltage differentials or elevated case temperatures, output current must be reduced per the SOA graph to avoid thermal shutdown activation. The internal current limit triggers at ~4A but is not intended for continuous operation.

Does the OPA544TG3 require external compensation for stability with capacitive loads?

Yes, the OPA544TG3 requires external output-stage compensation for reactive loads. The datasheet recommends a 1Ω resistor in series with a 0.01µF capacitor from VO to ground to ensure stability with high-capacitance or inductive loads such as motor windings or deflection coils. Without this network, complex load impedances may cause oscillation or ringing due to phase shift in the output stage.

Can the OPA544TG3 operate with asymmetric power supplies?

Yes, the OPA544TG3 supports unbalanced supplies - for example, V+ = +30V and V– = –6V - enabling rail-to-rail output swing down to 0V while keeping inputs within their linear common-mode range. Total supply voltage must remain ≤70V (V+ to V–), and the V– pin remains the reference for the heatsink tab. This configuration is commonly used in single-supply programmable power supplies.

What thermal management is required for OPA544TG3 at full 2A load?

At 2A output with ±35V supplies and worst-case 60V differential, power dissipation can exceed 120W. The OPA544TG3 requires a low-thermal-resistance heatsink (θ_SA ≤ 1.5°C/W typical) mounted to the V– tab, plus forced airflow or conduction cooling. Without heatsinking, θ_JA = 65°C/W limits usable power to <1W. Thermal shutdown activates at ~155°C junction temperature, so design margin must keep TJ ≤ 150°C under all operating conditions.

Is the OPA544TG3 pin-compatible with other devices in the OPA54x family?

Yes, the OPA544TG3 shares identical 5-lead TO-220 (KC) pinout and electrical interface with OPA547T and OPA548T. All three devices have matching V+, VIN+, VIN–, VO, and V– pin assignments and compatible SOA curves. However, OPA547T offers improved PSRR and higher quiescent current, while OPA548T adds enable/disable functionality - neither affects basic drop-in replacement in existing layouts.