Texas Instruments OPA544FKTTTG3

Overview

OPA544FKTTTG3 from Texas Instruments (formerly Burr-Brown) is a high-voltage, high-current operational amplifier designed for demanding power-driving applications. It delivers ≥2A continuous output current, operates from ±10V to ±35V supplies, and features 8V/µs slew rate and FET-input bias current ≤100pA. It drives motors, actuators, magnetic deflection coils, and programmable power supplies in industrial motion control and test equipment.

For engineers reviewing the OPA544FKTTTG3 datasheet, OPA544FKTTTG3 pinout, OPA544FKTTTG3 application, or OPA544FKTTTG3 equivalent, key selection criteria include safe operating area (SOA) compliance at elevated junction temperatures, thermal shutdown activation at ~155°C, internal current limit (~4A at 25°C, derated with temperature), and compatibility with unbalanced supplies up to 70V total.

Technical Context

The OPA544FKTTTG3 integrates high-performance FET input stage with a robust bipolar output stage on a single monolithic die. Its input stage provides ultra-low bias current (≤100pA) and high common-mode rejection (90–106dB), while the output stage supports ±2A continuous sourcing/sinking into resistive or reactive loads.

Thermal protection includes both internal current limiting-derating from ~4A at 25°C to ~1.5A at 125°C-and thermal shutdown triggered at ~155°C junction temperature. The device supports unbalanced supplies (e.g., –6V/+65V) as long as total V_S+–V_S– ≤ 70V and input common-mode range remains within (V_–) +6V to (V₊) –6V.

Key Specifications

Pinout & Package

The OPA544FKTTTG3 is housed in a 5-lead DDPAK/TO-263 (KTT) surface-mount package with exposed copper thermal tab electrically connected to the V_– pin. This package enables low θ_JA (as low as ~20°C/W with 4 in² copper) and requires soldering the tab to PCB copper for effective heat dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with OPA544FKTTTG3, the OPA547FKTTTG3 offers higher guaranteed output current and built-in overvoltage clamps, making it more robust in fault conditions, while the LM675T/NOPB trades integrated protection for lower cost and legacy package compatibility-but demands careful external thermal management.

Availability

OPA544FKTTTG3 is available at Aetrix Electronics and suitable for motor driver, programmable power supply, and servo amplifier applications requiring stable component supply, extended temperature operation (–40°C to +85°C), and reliable thermal protection.

Supply support for OPA544FKTTTG3 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 acquired Burr-Brown in 2000 and continues to manufacture, support, and qualify its precision analog portfolio-including high-performance power op amps.

The OPA544FKTTTG3 belongs to TI's OPA5xx family of high-voltage, high-current operational amplifiers, engineered specifically for industrial motion control, test instrumentation, and programmable power systems where reliability under sustained load and thermal stress is critical.

FAQ

What is the maximum safe continuous output current for OPA544FKTTTG3?

The OPA544FKTTTG3 guarantees ≥2A continuous output current under specified conditions (T_CASE = +25°C, V_S = ±35V, R_L ≥ 15Ω). Actual safe current depends on thermal management: with adequate heatsinking and ambient ≤40°C, it can sustain 2A continuously; without heatsink, current must be reduced per SOA curves to avoid thermal shutdown activation.

Does OPA544FKTTTG3 support unbalanced power supplies?

Yes, OPA544FKTTTG3 supports unbalanced supplies-for example, –6V on V_– and +65V on V₊, as long as total supply voltage (V₊ – V_–) does not exceed 70V and input common-mode voltage remains within (V_–) +6V to (V₊) –6V. This enables zero-output swing capability in single-supply-like configurations.

What thermal protection mechanisms does OPA544FKTTTG3 include?

OPA544FKTTTG3 includes two integrated thermal protections: (1) current limit that decreases from ~4A at 25°C to ~1.5A at 125°C, and (2) thermal shutdown that disables output at ~155°C junction temperature. Both functions are active simultaneously and require proper PCB copper area or external heatsink to maintain junction temperature ≤150°C for reliable operation.

Is external compensation required for OPA544FKTTTG3 stability?

Yes-OPA544FKTTTG3 requires external output-stage compensation for stability with reactive or capacitive loads. The datasheet recommends a 1Ω resistor in series with a 0.01µF capacitor from output to ground. Values may need adjustment depending on load impedance; instability manifests as ringing or oscillation during fast load transients.

What is the function of the exposed thermal tab on OPA544FKTTTG3?

The exposed thermal tab on OPA544FKTTTG3 is electrically connected to the V_– pin and serves dual purposes: (1) thermal conduction path to PCB copper or heatsink (reducing θ_JA significantly), and (2) low-inductance return path for high-current output. It must be soldered to a minimum 2 in² copper pour (1oz) and tied directly to the V_– net for optimal performance and reliability.