Texas Instruments TPS54317RHFR

Overview

TPS54317RHFR from Texas Instruments is a 3-A synchronous step-down DC/DC converter with adjustable output voltage down to 0.9 V, 60-mΩ high-side MOSFET, and externally adjustable switching frequency from 280 kHz to 1.6 MHz. It operates from 3-V to 6-V input, delivers ±1% output voltage accuracy, and integrates PowerPAD™ thermal enhancement in a 24-pin QFN package for high-density point-of-load regulation.

For engineers reviewing the TPS54317RHFR datasheet, TPS54317RHFR pinout, TPS54317RHFR application, or TPS54317RHFR equivalent, key selection considerations include its adjustable frequency via RT resistor, external compensation flexibility, fast transient response, integrated overcurrent and thermal protection, and compatibility with low-ESR ceramic output capacitors in compact 4 mm × 5 mm layouts.

Technical Context

The TPS54317RHFR implements a current-mode PWM control architecture with an internally compensated error amplifier (90–110 dB open-loop gain, 3–5 MHz unity-gain bandwidth) and adaptive dead-time logic. Its oscillator supports three modes: internal 350 kHz or 550 kHz (via SYNC pin), or externally set frequency (280–1600 kHz) using an RT-to-AGND resistor.

It features dual ground domains (AGND and PGND), separate bias regulation (VBIAS = 2.7–2.9 V), and a true power-good signal (PWRGD) with 90% Vref threshold and 3% hysteresis. Protection includes peak-current limiting (4–7.5 A trip), thermal shutdown (135–165 °C), and undervoltage lockout (2.95 V start, 2.8 V stop).

Key Specifications

Pinout & Package

TPS54317RHFR is housed in a thermally enhanced 24-pin QFN (RHF) package with exposed PowerPAD™ thermal pad (Pin 25). The package measures 4 mm × 5 mm with 0.5-mm pitch and requires soldering the PowerPAD to AGND for optimal thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck converter applications.

Compared with TPS54317RHFR, TPS54318RHLR offers plug-and-play simplicity at the cost of design flexibility, while MP2332HGTL-Z extends input voltage range but sacrifices frequency control and compensation customization-making TPS54317RHFR optimal for 3–6 V, high-performance, thermally constrained point-of-load designs.

Availability

TPS54317RHFR is available at Aetrix Electronics and suitable for point-of-load FPGA supplies, low-voltage DSP power rails, optical transceiver biasing, and industrial PLC digital I/O modules requiring stable component supply and long-term production continuity.

Supply support for TPS54317RHFR 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, embedded processing, and power management technologies, with decades of expertise in high-reliability power conversion ICs.

The TPS54317RHFR belongs to TI's SWIFT™ family of synchronous buck converters, designed specifically for high-density, high-efficiency point-of-load regulation in space-constrained digital systems such as networking, computing, and communications infrastructure.

FAQ

What is the recommended input capacitor configuration for TPS54317RHFR?

TI recommends placing a ≥10-µF X5R or X7R ceramic capacitor directly between each VIN pin (Pins 15–17) and adjacent PGND pins, with minimal trace length. A bulk electrolytic or polymer capacitor (e.g., 150 µF) may be added upstream for ripple suppression. The TPS54317RHFR datasheet specifies this configuration to maintain stability and minimize input voltage droop during high di/dt switching events.

Does TPS54317RHFR support output pre-bias startup?

No, the TPS54317RHFR does not support pre-bias startup. Its internal slow-start circuit ramps the reference voltage from 0 V to 0.891 V over ~3.35 ms, and the device will not regulate if the output voltage is already present at power-up. Attempting pre-bias operation may cause uncontrolled inrush current or latch-up. For pre-bias applications, consider TI's TPS54373 or other explicitly pre-bias-capable regulators.

How is thermal performance affected if the PowerPAD™ is not soldered to AGND?

Failure to solder the exposed PowerPAD™ (Pin 25) to AGND drastically degrades thermal performance: θ_JA increases from 19.7 °C/W to >50 °C/W, causing rapid junction temperature rise. At 3-A load, this can trigger thermal shutdown within seconds. TI's SLVS619B datasheet mandates soldering the PowerPAD to a dedicated AGND copper area with ≥6 thermal vias for reliable operation.

Can TPS54317RHFR be synchronized to an external clock source?

Yes, TPS54317RHFR supports external synchronization via the SYNC pin (Pin 20) across 330 kHz to 1600 kHz. To synchronize, drive SYNC with a clean CMOS-level clock and connect an RT resistor set to 80% of the target frequency (e.g., for 1 MHz sync, use RT for 800 kHz). The internal oscillator locks to the external signal, enabling EMI reduction and multi-rail phase alignment.

What is the maximum allowable voltage on the BOOT pin of TPS54317RHFR?

The absolute maximum voltage on the BOOT pin (Pin 3) is 17 V, per the TPS54317RHFR datasheet Absolute Maximum Ratings table. This rating applies during transient conditions (<20 ns), while steady-state operation limits BOOT to –0.3 V to 10 V. Exceeding 17 V-even briefly-risks permanent damage to the high-side gate driver. A 0.022–0.1-µF low-ESR ceramic capacitor between BOOT and PH is mandatory to sustain proper floating bias.