Texas Instruments TPS54331DDAR

Overview

TPS54331DDAR from Texas Instruments is a 28-V input, 3-A non-synchronous step-down DC-DC converter with integrated 80-mΩ high-side MOSFET, fixed 570-kHz switching frequency, Eco-mode pulse-skipping for light-load efficiency, and adjustable output down to 0.8 V - deployed in industrial power supplies, LCD displays, and battery-charger circuits.

For engineers reviewing the TPS54331DDAR datasheet, TPS54331DDAR pinout, TPS54331DDAR application, or TPS54331DDAR equivalent, key selection criteria include input voltage range (3.5–28 V), shutdown current (1 μA typ), UVLO programmability, thermal shutdown (165°C), and SOIC-8 PowerPAD™ package compatibility with high-current PCB layouts.

Technical Context

This device implements constant-frequency peak-current mode control with internal slope compensation, enabling stable operation with ceramic output capacitors and simplified loop compensation. The transconductance error amplifier (92 μA/V) interfaces directly with the COMP pin for external frequency compensation.

It features integrated overvoltage transient protection (OVTP) that disables the high-side MOSFET when VSENSE exceeds 109% of the 0.8-V reference, and frequency foldback that scales switching frequency down to 1/8th nominal (71 kHz) during severe overload or short-circuit conditions based on VSENSE voltage thresholds.

Key Specifications

Pinout & Package

TPS54331DDAR uses the SOIC-8 PowerPAD™ (DDA) package: 4.9 mm × 6 mm body with exposed thermal pad (Pin 9) requiring solder connection to PCB ground plane for optimal thermal performance (R_θJB = 25.5°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar step-down converter applications.

Compared with TPS54331DDAR, TPS54332DDAR trades light-load efficiency for higher switching frequency and smaller passives, while TPS54531DDAR retains identical control architecture and frequency but scales current delivery - both require revalidation of compensation and thermal design.

Availability

TPS54331DDAR is available at Aetrix Electronics and suitable for industrial power supplies, LCD display subsystems, and battery-charger auxiliary rails requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for TPS54331DDAR 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 ICs.

The TPS543xx family delivers highly integrated, thermally optimized buck converters targeting cost-sensitive, high-reliability industrial and consumer power applications - designed for minimal external components and robust fault protection.

FAQ

What is the maximum input voltage rating for the TPS54331DDAR?

The TPS54331DDAR has an absolute maximum input voltage rating of 30 V on the VIN pin, with recommended operation from 3.5 V to 28 V. Operation above 28 V is possible only for brief transients (e.g., load dump), and sustained voltage beyond 28 V risks exceeding thermal limits or triggering overvoltage protection. The device's internal high-side MOSFET is rated for 28-V operation, and the 30-V absolute max aligns with JEDEC stress limits.

Does the TPS54331DDAR support adjustable output voltage, and what is the minimum achievable value?

Yes, the TPS54331DDAR supports fully adjustable output voltage using an external resistor divider on the VSENSE pin. The internal voltage reference is 0.8 V ±2%, allowing outputs as low as 0.8 V with appropriate feedback scaling. For example, a 3.3-V output uses RO1 = 10 kΩ and RO2 = 3.24 kΩ. Output accuracy depends on resistor tolerance and reference drift, with total error typically within ±2% over temperature and line.

How does Eco-mode operate in the TPS54331DDAR, and at what load does it activate?

Eco-mode in the TPS54331DDAR activates automatically when peak inductor current falls below 160 mA (typical), causing the COMP pin voltage to clamp at 0.5 V and skip switching cycles. This reduces switching losses and maintains >85% efficiency at light loads (e.g., 10–50 mA). Exit occurs when load increases enough to raise COMP above 0.5 V. Eco-mode is transparent to the user - no configuration required - and improves battery runtime in always-on systems.

What thermal performance can be expected from the TPS54331DDAR in the DDA (PowerPAD™) package?

In the SOIC-8 PowerPAD™ (DDA) package, the TPS54331DDAR achieves a junction-to-board thermal resistance (R_θJB) of 25.5°C/W when the exposed pad is soldered to a 1-in² 2-oz copper plane. With proper PCB layout - including thermal vias under the PowerPAD™ - the device sustains 3-A continuous output at ambient temperatures up to 85°C without forced airflow. Junction temperature must remain below 150°C for reliable operation; thermal shutdown engages at 165°C.

Can the TPS54331DDAR be used with ceramic output capacitors, and what compensation guidance applies?

Yes, the TPS54331DDAR is explicitly designed for ceramic output capacitors, enabled by its current-mode control with internal slope compensation. TI recommends derating ceramic capacitance by 50–70% at rated DC bias due to voltage coefficient (e.g., a 47-μF 6.3-V X7R may deliver only ~15 μF at 3.3 V). Compensation uses a Type II network on the COMP pin; typical values for 3.3-V/3-A design are 47 pF + 10.2 kΩ in series with 29.4 kΩ to ground - validated in Section 8.2.1 of the datasheet.