Texas Instruments TPS54424RNVR

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, supports 200-kHz to 1.6-MHz switching frequency (adjustable via RT/CLK resistor or external clock), delivers 0.6-V to 12-V output with ±0.85% reference accuracy, and features hiccup current limiting and safe startup into pre-biased outputs - used in telecom power rails and server point-of-load regulation.

For engineers reviewing the TPS54424 datasheet, TPS54424 pinout, TPS54424 application, or TPS54424 equivalent, key selection criteria include its peak-current-mode control architecture, integrated MOSFET R_DS(on) values, PGOOD monitoring thresholds (±9% V_REF hysteresis), soft-start programmability via SS/TRK, and thermal shutdown at 170°C with 15°C hysteresis.

Technical Context

The TPS54424 implements peak-current-mode control with internal slope compensation for stable CCM operation across all loads, enabling fast transient response without complex loop compensation. Its oscillator includes a PLL synchronized to external clocks on the RT/CLK pin, supporting precise timing coordination in multi-rail systems.

It uses a bootstrap gate-drive architecture with BOOT-SW UVLO (2.2 V typical) to sustain 100% duty cycle operation while maintaining high-side MOSFET drive integrity. The error amplifier (1100 µA/V transconductance) compares FB against either the 0.6-V reference or SS/TRK voltage, enabling tracking and sequencing functionality.

Key Specifications

Pinout & Package

TPS54424 is housed in an 18-pin RNV (VQFN-HR) package, 3.5 mm × 3.5 mm, with exposed thermal pad. Pin 1 is BOOT; pins 2 and 11 are VIN; pins 3, 4, 5, 8, 9, 10 are PGND; pins 6 and 7 are SW; AGND is pin 12; RT/CLK is pin 13; FB is pin 14; COMP is pin 15; SS/TRK is pin 16; EN is pin 17; PGOOD is pin 18.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS54424, TPS54427RNVR offers higher current and advanced control mode but same footprint, while MP2342DJ-LF-P trades supervision and flexibility for lower BOM cost - making TPS54424 optimal for balanced performance, reliability, and design simplicity in telecom and server PoL.

Availability

TPS54424 is available at Aetrix Electronics and suitable for telecom infrastructure, server point-of-load, and medical imaging equipment requiring stable component supply, long-term lifecycle support, and traceable sourcing.

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 technologies, with decades of expertise in high-reliability power conversion ICs.

The TPS54424 belongs to TI's SWIFT™ synchronous buck converter family, designed specifically for space-constrained, high-efficiency DC/DC applications in telecom, enterprise networking, and industrial computing.

FAQ

What is the maximum input voltage rating for the TPS54424?

The TPS54424 has an absolute maximum input voltage rating of 19 V, with recommended operating range from 4.5 V to 17 V. Exceeding 19 V risks permanent damage. The device includes VIN UVLO with 4.1-V rising threshold and 3.7-V falling threshold, plus 200-mV hysteresis, ensuring robust startup and brownout recovery. Always verify input transient margins in final design per TI's SLVSDV8 datasheet.

How does the TPS54424 achieve safe startup into a pre-biased output?

The TPS54424 prevents reverse current flow during startup into a pre-biased rail by disabling the low-side MOSFET until the internal soft-start ramp reaches the output voltage level. This behavior is inherent to its peak-current-mode architecture and controlled by the SS/TRK pin voltage versus FB. No external diode or circuitry is needed - the TPS54424 handles it autonomously, protecting downstream loads and maintaining regulation integrity.

Can the TPS54424 synchronize to an external clock, and how is it configured?

Yes, the TPS54424 can synchronize to an external clock via the RT/CLK pin. When driven with a logic-level square wave (VIH ≥ 2 V, VIL ≤ 0.8 V), the internal PLL locks to the falling edge of the input clock. The synchronization range is 200 kHz to 1.6 MHz. To enable PLL mode, leave the RT resistor unconnected and apply the clock signal directly - no additional configuration is required. This feature minimizes beat frequencies in multi-rail systems.

What are the thermal limitations and protections built into the TPS54424?

The TPS54424 includes non-latch thermal shutdown that trips at 170°C junction temperature and restarts automatically after cooling by 15°C. Its RθJA is 57.1°C/W (JEDEC) and 34°C/W (EVM), with θJCbot at 1.2°C/W - indicating strong bottom-side thermal conduction. The exposed thermal pad must be soldered to a large copper plane. Thermal derating curves in the datasheet show output current reduction above 85°C ambient, ensuring safe operation under sustained load.

Does the TPS54424 support adjustable input undervoltage lockout (UVLO), and how is it implemented?

Yes, the TPS54424 supports adjustable input UVLO using the EN pin. An external resistor divider from VIN to EN sets the turn-on threshold: V_{EN_RISE} ≈ 1.26 V (typical). With internal 1.2-µA pull-up current (Ip) and 3.6-µA hysteresis current (Ih), the divider defines both rising and falling thresholds. For example, R_TOP = 1 MΩ and R_BOT = 130 kΩ yields ~4.5-V UVLO with ~150-mV hysteresis - fully configurable without additional ICs.