Texas Instruments TPS75733KC

Overview

TPS75733KC from Texas Instruments is a 3-A, 3.3-V fixed-output low-dropout (LDO) voltage regulator in TO-220 (KC) package, featuring 150 mV typical dropout at 3 A, 125 µA quiescent current, and open-drain power-good (PG) output. It delivers stable 3.3-V rail for microcontroller core supplies, FPGA I/O banks, and industrial PLC modules requiring high-current, low-noise regulation with fast transient response.

For engineers reviewing the TPS75733KC datasheet, TPS75733KC pinout, TPS75733KC application, or TPS75733KC equivalent, key selection criteria include dropout performance at full load, thermal behavior in TO-220 mounting, PG timing thresholds (91% VO trip), and compatibility with 100-µF ceramic or tantalum output capacitors per TI's stability guidelines.

Technical Context

The TPS75733KC uses a PMOS pass element enabling low dropout (150 mV @ 3 A) and load-independent quiescent current (125 µA). Its bandgap reference (1.22 V) feeds an error amplifier controlling the pass device, with internal UVLO (2.2–2.75 V) and thermal shutdown (150°C).

Power-good logic monitors regulated output voltage with 91% VO falling-edge trip and 0.5% VO hysteresis, driving an open-drain PG terminal requiring external pull-up. Enable (EN) is active-low, supporting TTL-compatible shutdown with <1 µA standby current.

Key Specifications

Pinout & Package

TPS75733KC is housed in a 5-pin TO-220 (KC) package with exposed thermal tab electrically connected to GND. Mounting requires mechanical fixation and thermal interface to heatsink or PCB copper plane for >1.5 W dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO regulator applications.

Compared with TPS75733KTT, the TPS75733KC offers identical regulation performance but trades thermal efficiency for mechanical robustness and heatsink compatibility; versus TPS7A4701RGWR, it prioritizes high-current digital rail delivery and built-in power sequencing over ultra-low noise.

Availability

TPS75733KC is available at Aetrix Electronics and suitable for industrial PLC modules, automotive body control units, and FPGA-based test equipment requiring stable component supply with long-term manufacturability and thermal reliability in TO-220 form factor.

Supply support for TPS75733KC 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 power management IC design and manufacturing.

The TPS757xx family was engineered for high-current, low-dropout regulation in industrial and automotive systems where thermal resilience, fast transient response, and integrated power sequencing are critical.

FAQ

What is the maximum input voltage for TPS75733KC?

The absolute maximum input voltage for TPS75733KC is 6 V, but the recommended operating range is 2.8 V to 5.5 V. Exceeding 5.5 V risks permanent damage. For reliable 3.3-V output at 3 A, minimum input is 3.6 V (3.3 V + 300 mV max dropout), per datasheet Figure 12 and Section "Recommended Operating Conditions".

Does TPS75733KC require an external feedback resistor network?

No, TPS75733KC is a fixed-output variant and does not require external feedback resistors. The FB/PG pin serves solely as an open-drain power-good output. External pull-up (e.g., 10 kΩ to VO) is mandatory for PG functionality, as specified in the Terminal Functions table and Figure 1.

How does the power-good (PG) output behave during startup and fault conditions?

The PG output of TPS75733KC is active-low and open-drain. It transitions low when VO reaches ≥91% of 3.3 V (≈3.003 V) and goes high-impedance when VO falls ≤89% (≈2.937 V). During startup, PG remains high-Z until regulation is achieved; under overload or input brownout, PG asserts high-Z to signal fault, per Figure 4 timing diagram and Electrical Characteristics table.

Can TPS75733KC be used without a heatsink in a 3-A application?

At 3 A with 5.5-V input and 3.3-V output, TPS75733KC dissipates ~6.6 W (VI−VO)×IO. With R_θJA = 58.7°C/W (TO-220, no heatsink), junction temperature would exceed 150°C even at 25°C ambient. A heatsink (R_θSA ≤22°C/W) or PCB copper plane is required-per Thermal Information Section and Figure 22-for safe continuous operation.

What output capacitor value and type are recommended for TPS75733KC stability?

TI specifies 100 µF output capacitance with low ESR (≤20 mΩ) for stable operation of TPS75733KC. Ceramic (X5R/X7R) or polymer tantalum capacitors are preferred; aluminum electrolytics are discouraged due to higher ESR and aging effects. Figure 19/20 confirm stability region for Co = 47–680 µF, with 100 µF being the validated baseline.