Texas Instruments TPS54355PWPR

Overview

TPS54355PWPR from Texas Instruments is a 2.5-V fixed-output, synchronous buck PWM converter with integrated 100-mΩ high-side MOSFET and external low-side MOSFET drive capability. It delivers up to 3-A continuous output current at 95% peak efficiency (VI = 12 V, VO = 3.3 V), supports 250–700 kHz adjustable switching frequency, features internal slow-start (4.4 ms typical), and operates across 4.5–20 V input range. It is used in point-of-load regulation for FPGAs and ASICs requiring stable, compact DC/DC conversion.

For engineers reviewing the TPS54355PWPR datasheet, TPS54355PWPR pinout, TPS54355PWPR application, or TPS54355PWPR equivalent, key selection considerations include its 2.5-V fixed output, 16-pin TSSOP PowerPAD package with thermal pad, 180° synchronization capability, undervoltage lockout adjustability via UVLO pin, and compatibility with external low-side MOSFETs or Schottky diodes.

Technical Context

The TPS54355PWPR implements a feed-forward modulator with constant 8 V/V gain, adaptive dead-time control to prevent shoot-through, and a high-performance voltage error amplifier (60 dB open-loop gain, 2 MHz unity-gain bandwidth). Its PWM control logic integrates oscillator, current limit detection, and latch-based duty-cycle generation with minimum controllable on-time of 180 ns.

It uses an internally compensated voltage-mode control architecture with a precision 0.891-V reference trimmed during production. The device supports bidirectional SYNC operation-output mode when RT is grounded/floating (180° out-of-phase PH edge), input mode when RT is resistor-set-and includes hiccup-mode overcurrent protection with 4.5-ms recovery time at 500 kHz.

Key Specifications

Pinout & Package

TPS54355PWPR is housed in a thermally enhanced 16-pin HTSSOP (PWP) package with exposed PowerPAD™ thermal pad, requiring solder connection to PGND/AGND plane for optimal junction-to-ambient thermal performance (42.1°C/W with soldered pad).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS54355PWPR, TPS54356PWPR offers identical functionality at 3.3 V but requires revalidation of feedback and UVLO networks, while LM2678SD-2.5/NOPB sacrifices efficiency, thermal performance, and advanced features like SYNC and LSG drive for reduced BOM cost and SO-8 footprint.

Availability

TPS54355PWPR is available at Aetrix Electronics and suitable for FPGA power delivery, ASIC core supplies, LCD monitor subsystems, and industrial peripheral DC/DC conversion requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for TPS54355PWPR 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 TPS5435x family was designed specifically for medium-current, space-constrained point-of-load applications in computing, industrial, and consumer electronics - emphasizing integration, thermal performance, and system-level features like synchronization and power good signaling.

FAQ

What is the output voltage tolerance of the TPS54355PWPR under full load and temperature?

The TPS54355PWPR delivers a fixed 2.5-V output with ±1% tolerance (2.45 V to 2.55 V) across 100 mA to 3 A load and −40°C to +125°C junction temperature. This specification is verified per Electrical Characteristics table on page 4 of the SLVS519A datasheet and reflects tight regulation enabled by internal trimming of the 0.891-V reference and error amplifier offset.

Can the TPS54355PWPR operate without an external low-side MOSFET?

Yes, the TPS54355PWPR can operate with only an external Schottky diode connected from PH to PGND. In this configuration, the integrated pulldown MOSFET handles light-load CCM operation, but efficiency drops compared to synchronous mode. The LSG pin must remain unconnected, and inductor selection must ensure peak current stays below 0.3 A during high-side off-time to avoid overstressing the internal MOSFET.

How does the SYNC pin function in TPS54355PWPR when RT is left floating?

When the RT pin is floating, the TPS54355PWPR operates at 500 kHz and configures SYNC as an output that generates a falling-edge signal approximately 180° out-of-phase with the rising edge of the PH pin. This allows direct interleaving with a second TPS5435x device to reduce input ripple current and RMS input capacitor stress - no external clock source required.

What thermal performance can be expected from the TPS54355PWPR in a standard 2-layer PCB layout?

With the PowerPAD soldered to a 2 oz. copper thermal pad (3″ × 3″), 2 thermal vias, and proper AGND/PGND connections, the TPS54355PWPR achieves a junction-to-ambient thermal impedance of 42.1°C/W. At 3-A load and 12-V input, typical power dissipation is ~1.2 W, resulting in ~50°C junction rise above ambient - well within the 125°C max operating junction temperature.

Is the TPS54355PWPR RoHS-compliant and lead-free?

Yes, the TPS54355PWPR is manufactured in accordance with RoHS Directive 2011/65/EU and is lead-free. The HTSSOP (PWP) package uses matte tin lead finish, and the device meets TI's green chemistry standards. Full compliance documentation, including material declarations and test reports, is available through TI's Quality & Environmental Information portal.