Texas Instruments TPS54418ARTET

Overview

TPS54418ARTET from Texas Instruments is a 2.95-V to 6-V input, 4-A synchronous step-down DC/DC converter with integrated high- and low-side 30-mΩ MOSFETs, 0.8 V ±1% voltage reference, adjustable 200 kHz–2 MHz switching frequency via RT/CLK pin, and open-drain PWRGD output for power-good monitoring in FPGA and ASIC point-of-load applications.

For engineers reviewing the TPS54418ARTET datasheet, TPS54418ARTET pinout, TPS54418ARTET application, or TPS54418ARTET equivalent, key selection considerations include its WQFN-16 (3 mm × 3 mm) thermally enhanced package, cycle-by-cycle current limit, safe startup into prebiased outputs, UV/OV protection, and soft-start sequencing capability for multi-rail systems.

Technical Context

The TPS54418ARTET implements peak-current-mode control with internal slope compensation to prevent subharmonic oscillation across duty cycles up to 100%, enabled by BOOT-PH UVLO monitoring and integrated boot diode. Its transconductance error amplifier (225 µS normal / 70 µS soft-start mode) compares VSENSE against either the 0.8 V reference or SS pin voltage, supporting precise regulation under dynamic load conditions.

Switching frequency is set via resistor on RT/CLK (200–2000 kHz) or synchronized to external clock with 14 µs PLL lock time; EN pin provides programmable UVLO with 2.55 µA hysteresis current, while PWRGD asserts low when VSENSE falls outside 93–107% of nominal output, with 2% hysteresis.

Key Specifications

Pinout & Package

TPS54418ARTET uses a thermally enhanced 3 mm × 3 mm, 16-pin WQFN package with exposed PowerPad for PCB ground connection and thermal dissipation. The PowerPad must be soldered to an internal ground plane using ≥4 thermal vias.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS54418ARTET, TPS54428RTET offers lower reference and higher current headroom but requires circuit redesign, while MP2451DT-LF-Z sacrifices integration and protection for footprint and cost-making TPS54418ARTET optimal for 4-A, feature-rich POL designs.

Availability

TPS54418ARTET is available at Aetrix Electronics and suitable for FPGA power delivery, ASIC point-of-load regulation, and optical module DC/DC conversion requiring stable component supply across automotive-grade temperature ranges and long production lifecycles.

Supply support for TPS54418ARTET 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 ICs, with decades of expertise in high-efficiency DC/DC conversion and industrial-grade reliability.

The TPS54418ARTET belongs to TI's SWIFT™ synchronous buck converter family, designed specifically for high-density, high-performance point-of-load regulation in FPGAs, ASICs, DSPs, and telecom infrastructure equipment.

FAQ

What is the minimum recommended soft-start capacitor value for TPS54418ARTET?

The TPS54418ARTET integrates a 1.8 µA soft-start charging current. For a 2-ms ramp time, a 2.2 nF capacitor is required (CSS = tSS × ISS / VREF). Values between 1 nF and 22 nF are typical, with 4.7 nF commonly used to achieve ~4-ms startup while avoiding excessive delay in system boot sequences. Always verify with actual load and input conditions.

Does TPS54418ARTET support 100% duty cycle operation?

Yes, the TPS54418ARTET supports near-100% duty cycle operation as long as the BOOT-to-PH voltage remains above 2.5 V, enforced by an internal UVLO circuit. This enables low-dropout regulation in applications like 3.3 V-to-3.0 V conversion where minimal input-output differential is critical, without requiring external components.

How is the switching frequency set on TPS54418ARTET?

The TPS54418ARTET switching frequency is set either by connecting a resistor from RT/CLK to GND (200–2000 kHz range) or by applying an external clock signal (300–2000 kHz) to the same pin. With a 400-kΩ resistor, fSW is typically 500 kHz. The device includes a PLL for fast synchronization (<14 µs lock time) to external clocks for EMI reduction.

Can TPS54418ARTET safely start up into a precharged output capacitor?

Yes, the TPS54418ARTET includes safe start-up into prebiased outputs. During startup, the device detects VSENSE > reference and inhibits high-side FET turn-on until the output begins regulating downward, preventing reverse current flow and potential damage to upstream sources or downstream loads.

What thermal performance can be expected from TPS54418ARTET in a standard 4-layer PCB layout?

On a JEDEC-standard 4-layer board (2 oz copper, 4 thermal vias under PowerPad), the TPS54418ARTET achieves R_θJA = 37°C/W. At 4 A output with 5 V input and 1.8 V output, typical power dissipation is ~0.6 W, resulting in ~22°C temperature rise above ambient-well within the –40°C to +150°C operating junction range.