Texas Instruments TPS54424RNVT

Overview

TPS54424 from Texas Instruments is a 4.5-V to 17-V input, 4-A synchronous step-down DC/DC converter in a 3.5-mm × 3.5-mm HotRod™ QFN package. It integrates 14.1-mΩ high-side and 6.1-mΩ low-side MOSFETs, features peak current mode control with 200-kHz to 1.6-MHz adjustable switching frequency, and delivers ±0.85% reference accuracy at 0.6 V for precision point-of-load regulation in telecom power supplies.

For engineers reviewing the TPS54424 datasheet, TPS54424 pinout, TPS54424 application, or TPS54424 equivalent, key selection criteria include its hiccup current limit, safe startup into pre-biased outputs, PGOOD monitoring with 91–106% VREF window, RT/CLK synchronization capability, and thermal shutdown with 15°C hysteresis - all critical for reliable server and infrastructure power design.

Technical Context

The TPS54424 implements constant-frequency peak current mode control with internal slope compensation to prevent subharmonic oscillation across 0–100% duty cycle. Its integrated high- and low-side n-channel MOSFETs enable CCM operation under all load conditions while minimizing external component count.

Switching frequency is set via an external resistor on RT/CLK (200–1600 kHz) or synchronized to an external clock using PLL architecture. The BOOT-SW UVLO (2.2–2.6 V) enables 100% duty cycle operation when bootstrap voltage remains above threshold, and the error amplifier (1100 µA/V transconductance) drives COMP for loop compensation with fast transient response.

Key Specifications

Pinout & Package

TPS54424 uses the RNV (18-pin VQFN-HR) package, 3.5 mm × 3.5 mm, with exposed thermal pad for enhanced junction-to-board thermal resistance (1.2 °C/W bottom-side).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS54427RNVT and MP2342DL-LF-Z, the TPS54424 offers unique RT/CLK synchronization, hiccup current limiting, and 91–106% PGOOD window - making it the only choice for systems requiring deterministic timing alignment and robust fault containment in mission-critical infrastructure.

Availability

TPS54424 is available at Aetrix Electronics and suitable for telecom infrastructure, enterprise server power, and medical imaging equipment requiring stable component supply and long-term production continuity.

Supply support for TPS54424 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-reliability power conversion solutions.

The TPS54424 belongs to TI's SWIFT™ synchronous buck converter family, engineered for space-constrained, high-efficiency point-of-load applications in telecom, server, and industrial systems where thermal performance and transient response are critical.

FAQ

What is the minimum input voltage required for TPS54424 to begin regulation?

The TPS54424 has a typical VIN under-voltage lockout (UVLO) rising threshold of 4.3 V, with hysteresis of 0.2 V. Regulation begins once VIN exceeds this threshold and EN is asserted. Below 4.1 V, the device remains disabled; the absolute minimum operating VIN is 4.5 V per recommended conditions. This ensures stable gate drive and internal bias generation for the integrated MOSFETs and control circuitry in the TPS54424.

Can TPS54424 safely start up into a pre-biased output voltage?

Yes, the TPS54424 is explicitly designed for safe monotonic startup into pre-biased outputs. Its internal architecture prevents reverse current flow by controlling high-side MOSFET turn-on timing relative to output voltage ramp. This feature is confirmed in the datasheet's "Safe Start-Up into Pre-Biased Output Voltage" section and is critical for hot-swap and redundant power applications where the TPS54424 may be inserted into an already-powered rail.

How is switching frequency set on the TPS54424, and what is the valid resistor range for RT/CLK?

Switching frequency on the TPS54424 is set via an external resistor from RT/CLK to AGND. A 100-kΩ resistor yields ~500 kHz, while 30.1 kΩ sets maximum 1.6 MHz. Valid range spans 200 kHz (250 kΩ) to 1.6 MHz (30.1 kΩ). The TPS54424 also supports external clock synchronization on the same pin, enabling system-level EMI reduction - a capability not replicated in many competing 4-A buck converters like the TPS54424.

What protection features does the TPS54424 include beyond overcurrent and thermal shutdown?

The TPS54424 includes output overvoltage protection (OVP), hiccup-mode current limiting, PGOOD monitoring with 91–106% VREF window and deglitch timing, BOOT-SW UVLO, and input UVLO with hysteresis. OVP disables the high-side MOSFET if FB exceeds 108% VREF and holds off until FB drops below 106%. These layered protections ensure robust operation in unattended infrastructure systems where the TPS54424 serves as primary power for sensitive digital loads.

Is the TPS54424 pin-compatible with other devices in the TPS544xx family?

No, the TPS54424 is not pin-compatible with other TPS544xx variants such as TPS54425, TPS54426, or TPS54427. While all share the RNV package, pin functions differ - notably, TPS54427 replaces SS/TRK with MODE and lacks dedicated PGOOD. The TPS54424's unique pin mapping (e.g., dual VIN, six PGND, RT/CLK sync) is optimized for its specific control architecture and cannot be substituted without PCB redesign. Always verify pinout against the TPS54424 datasheet before layout.