Texas Instruments TPS54239DDAR

Overview

TPS54239DDAR from Texas Instruments is a 2-A synchronous step-down DC/DC converter with integrated high-side (140 mΩ) and low-side (70 mΩ) N-channel MOSFETs, D-CAP2™ adaptive on-time control, 600-kHz switching frequency, and 0.76–7.0-V adjustable output voltage. It delivers stable power in space-constrained digital TV, Blu-ray player, and STB power rails.

For engineers reviewing the TPS54239DDAR datasheet, TPS54239DDAR pinout, TPS54239DDAR application, or TPS54239DDAR equivalent, key selection criteria include input voltage range (4.5–23 V), thermal pad–enabled SO PowerPAD™ package, pre-biased soft-start capability, cycle-by-cycle overcurrent protection, and compatibility with ceramic output capacitors.

Technical Context

The TPS54239DDAR implements D-CAP2™ mode control-combining adaptive on-time PWM with internal ripple-simulation ramp-to achieve fast transient response without external compensation. Its control loop operates without an oscillator, deriving on-time from VIN and VOUT to maintain pseudo-constant 600-kHz frequency across input and load variations.

It integrates dual N-FETs with matched RDS(on) values, a 5.5-V VREG5 LDO for gate drive bias, and proprietary pre-biased soft-start logic that incrementally enables synchronous rectification to avoid output sinking during startup. Protection includes non-latching thermal shutdown (165°C), hiccup-mode UVP (65% VOUT), and OVP (125% VOUT).

Key Specifications

Pinout & Package

The TPS54239DDAR uses an 8-pin SO PowerPAD™ (DDA) package with exposed thermal pad soldered to PCB ground for enhanced thermal dissipation (θJA = 46.2°C/W). The thermal pad must be connected to a dedicated PGND copper area using ≥4 thermal vias.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS54239DDAR, TPS54229DDAR offers identical layout compatibility but reduced current headroom, while MP2307DN-LF-Z trades integrated features for lower unit cost-making TPS54239DDAR optimal for designs demanding robust startup, thermal performance, and minimal external components.

Availability

TPS54239DDAR is available at Aetrix Electronics and suitable for digital TV, Blu-ray player, and networking home terminal applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for TPS54239DDAR 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 TPS54239DDAR belongs to TI's SWIFT™ synchronous buck converter family, designed specifically for cost-sensitive, space-constrained consumer electronics requiring fast transient response and ceramic-capacitor compatibility.

FAQ

What is the maximum recommended junction temperature for continuous operation of the TPS54239DDAR?

The TPS54239DDAR is rated for continuous operation up to 150°C junction temperature. Thermal shutdown activates at 165°C with 40°C hysteresis, ensuring safe recovery before re-enabling. For reliable long-term performance in sealed enclosures, derate output current above 100°C TJ using the thermal resistance data (θJA = 46.2°C/W) and ambient temperature estimates.

Does the TPS54239DDAR support pre-biased output startup, and how is it implemented?

Yes, the TPS54239DDAR supports pre-biased soft-start. When the output voltage exceeds the soft-start command level at power-up, the controller initiates low-side FET gate pulses with narrow on-time and incrementally increases conduction width cycle-by-cycle until reaching normal duty-cycle operation. This prevents reverse current flow and ensures monotonic VOUT ramp-up without sinking charge from the pre-biased rail.

What is the purpose of the VREG5 pin on the TPS54239DDAR, and what external component is required?

The VREG5 pin on the TPS54239DDAR provides a regulated 5.5-V output used internally to power gate drivers and control circuitry. A 0.47-μF ceramic capacitor must be placed between VREG5 and GND, located close to the device. This capacitor stabilizes the LDO output and ensures reliable high-side FET turn-on; omission causes erratic switching or failure to start.

Can the TPS54239DDAR operate with only ceramic output capacitors, and why is this significant?

Yes, the TPS54239DDAR is explicitly designed to operate stably with ultra-low-ESR ceramic output capacitors (including X5R/X7R types), enabled by its D-CAP2™ control architecture and internal ripple-simulation ramp. This eliminates reliance on higher-ESR electrolytic or polymer capacitors, reducing solution size, improving reliability, and lowering total BOM cost in high-volume consumer applications.

What is the minimum off-time specification for the TPS54239DDAR, and how does it affect low-duty-cycle operation?

The TPS54239DDAR has a minimum off-time (tOFF(MIN)) of 260–310 ns, which limits the lowest achievable duty cycle at 600-kHz switching. At VIN = 23 V and VOUT = 0.76 V, the theoretical duty cycle is ~3.3%, requiring tOFF ≈ 1367 ns-well above the minimum, ensuring stable operation. This spec guarantees reliable regulation down to 0.76 V across the full 4.5–23-V input range without pulse-skipping artifacts.