Texas Instruments TPS54334DDAR

Overview

TPS54334DDAR from Texas Instruments is a 4.2-V to 28-V input, 3-A synchronous step-down DC/DC converter with integrated 128 mΩ/84 mΩ MOSFETs, fixed 570 kHz switching frequency, 0.8 V ±1.5% reference voltage, and power-good (PGOOD) monitoring - used in industrial power supplies, LCD displays, and distributed 5V/12V bus regulation.

For engineers reviewing the TPS54334DDAR datasheet, TPS54334DDAR pinout, TPS54334DDAR application, or TPS54334DDAR equivalent, key selection considerations include input UVLO threshold (4.2 V), shutdown quiescent current (2 µA), monotonic start-up into pre-biased outputs, hiccup-mode overcurrent protection, and SOIC-8 PowerPAD™ thermal performance (R_θJA = 42.1°C/W).

Technical Context

The TPS54334DDAR implements fixed-frequency peak current mode control with internal slope compensation to prevent subharmonic oscillation across duty cycles. Its transconductance error amplifier (1300 µA/V) drives the COMP pin for loop stability, while boot capacitor recharge is managed via integrated bootstrap diode and BOOT-SW UVLO (2.2 V typical).

Protection architecture includes cycle-by-cycle high-side current limiting (5.2 A typ), bidirectional low-side current limiting (sourcing/sinking), thermal shutdown at 165°C with 10°C hysteresis, and overvoltage detection that disables the high-side MOSFET when VSENSE exceeds 116% of V_REF, re-enabling only below 110%.

Key Specifications

Pinout & Package

TPS54334DDAR uses an 8-pin SOIC package with exposed PowerPAD™ thermal pad (4.89 mm × 3.90 mm). The thermal pad must be soldered to PCB ground plane using multiple vias for optimal thermal dissipation (R_θJB = 31.8°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS54334DDAR, TPS54335ADDAR offers frequency flexibility and higher current but removes PGOOD functionality, while MP2334HG-33-LF-Z trades input range and adjustability for simplified fixed-output implementation - all require PCB layout review due to differing thermal and routing requirements.

Availability

TPS54334DDAR is available at Aetrix Electronics and suitable for industrial sensor nodes, consumer display power supplies, and automotive infotainment core supplies requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for TPS54334DDAR 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 TPS543xx family delivers highly integrated, thermally robust synchronous buck converters targeting space-constrained, high-efficiency applications in industrial, automotive, and consumer electronics - designed for minimal external components and robust fault handling.

FAQ

What is the maximum input voltage rating for the TPS54334DDAR?

The TPS54334DDAR has an absolute maximum input voltage rating of 30 V on the VIN pin, with recommended operating range from 4.2 V to 28 V. Exceeding 30 V risks permanent damage per JEDEC stress ratings. For reliable operation in automotive or industrial environments with voltage transients, design margins should maintain VIN ≤ 28 V under all normal and fault conditions. The TPS54334DDAR's internal UVLO (4.2 V rising threshold) ensures safe startup only when sufficient input is present.

Does the TPS54334DDAR support adjustable output voltage?

Yes, the TPS54334DDAR supports fully adjustable output voltage from 0.8 V to 24 V using an external resistor divider on the VSENSE pin. The internal 0.8 V ±1.5% reference sets V_OUT = 0.8 × (1 + R1/R2). TI recommends 1% tolerance resistors and cautions against excessively high divider values (>1 MΩ) due to VSENSE input bias current effects. The TPS54334DDAR does not offer factory-trimmed fixed outputs - all configurations require external feedback components.

How does the PGOOD function work on the TPS54334DDAR?

The TPS54334DDAR's PGOOD pin is an open-drain output that pulls low when VSENSE falls below 84% or rises above 116% of the 0.8 V reference, indicating output fault. It floats (high-impedance) when VSENSE is between 90% and 110% of V_REF, signaling valid regulation. A 10–100 kΩ pull-up resistor to ≤5.5 V is required. Full sink capability (0.3 V @ 0.35 mA) is achieved only when VIN > 4.2 V; below that, PGOOD remains functional but with reduced drive strength.

Can the TPS54334DDAR safely start up into a pre-biased output?

Yes, the TPS54334DDAR features monotonic start-up into pre-biased outputs. During startup, both high-side and low-side MOSFETs remain disabled until the internal soft-start voltage exceeds the voltage on the VSENSE pin - preventing reverse current flow from the pre-charged output into the converter. This behavior is confirmed in the device's functional description and is critical for hot-swap and multi-rail systems where downstream capacitors may retain charge before main power application. The TPS54334DDAR implements this without external components.

What thermal management guidance applies to the TPS54334DDAR in SOIC-8 PowerPAD™ package?

The TPS54334DDAR in DDAR package requires soldering the exposed PowerPAD™ thermal pad to a PCB ground plane using ≥4 thermal vias (0.3 mm diameter, filled or plated) to achieve specified R_θJB = 31.8°C/W. Without proper pad connection, junction temperature rise increases significantly - potentially triggering thermal shutdown at <2 A load. Layout guidelines mandate minimizing copper isolation around the pad and avoiding solder mask coverage on the pad surface. The TPS54334DDAR's SOIC footprint is incompatible with standard SOIC thermal relief patterns; dedicated thermal land pattern per TI SLUSC26A is mandatory.