Texas Instruments LM5013DDAR

Overview

LM5013DDAR from Texas Instruments is a 100-V input, 3.5-A non-synchronous buck DC/DC converter with integrated 100-V/0.25-Ω high-side NMOS FET, constant on-time (COT) control, and ultra-low 3.1-µA shutdown quiescent current. It delivers regulated 12-V output from 48-V nominal industrial bus rails in motor drives and transport power supplies.

For engineers reviewing the LM5013DDAR datasheet, LM5013DDAR pinout, LM5013DDAR application, or LM5013DDAR equivalent, key selection considerations include its 50-ns minimum on-time for high step-down ratios, 1.2-V internal reference accuracy, open-drain PGOOD for sequencing, and SO PowerPAD™ thermal performance in high-voltage industrial environments.

Technical Context

The LM5013DDAR implements a voltage-mode COT architecture with VIN feedforward to maintain quasi-fixed switching frequency across 6–100 V input. Its programmable on-time (via R_RON) enables adaptive pulse width control, while the integrated bootstrap diode and internal 5-V VCC regulator eliminate external bias components.

It features cycle-by-cycle peak current limiting at 3.7–5 A, thermal shutdown at 175°C with 10°C hysteresis, and precision enable/UVLO with 1.5-V rising threshold. The 1.27-mm pin pitch SO PowerPAD™ package supports high-voltage creepage and low thermal resistance (R_θJC(bot) = 1.3°C/W).

Key Specifications

Pinout & Package

The LM5013DDAR is housed in an 8-pin SO PowerPAD™ (DDA) package with 1.27-mm pin pitch and exposed thermal pad (EP) for enhanced heat dissipation. The package measures 4.89 mm × 3.90 mm and supports >3 mm creepage for 100-V applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM5012DDAR, the LM5013DDAR delivers 40% higher output current in the same footprint; compared with LM5013QDDARQ1, it offers identical electrical performance at lower cost and without automotive qualification overhead for industrial use.

Availability

LM5013DDAR is available at Aetrix Electronics and suitable for industrial motor drives, hybrid vehicle auxiliary power, telecom PoE++ systems, and high-cell-count battery management requiring stable component supply and long-term manufacturability.

Supply support for LM5013DDAR 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 designing analog ICs, embedded processors, and power management solutions for industrial, automotive, and communications markets.

The LM5013DDAR belongs to TI's high-voltage DC/DC converter product line, engineered for rugged industrial power conversion with wide input range, ultra-low IQ, and integrated FETs to simplify 6–100 V system designs.

FAQ

What is the minimum recommended input voltage for stable operation of the LM5013DDAR?

The LM5013DDAR operates down to 6 V input while maintaining regulation, supporting applications such as deeply discharged battery systems. At this minimum voltage, it achieves nearly 100% duty cycle to sustain output voltage. Operation below 6 V risks UVLO activation and shutdown, as confirmed in Section 7.3 Recommended Operating Conditions of the datasheet. The LM5013DDAR's ability to function at 6 V makes it suitable for brownout-tolerant industrial controls where input rails may dip during transients.

Does the LM5013DDAR require external loop compensation components?

No, the LM5013DDAR does not require external loop compensation components due to its constant on-time (COT) control architecture. Stability is achieved through inherent input voltage feedforward and feedback ripple requirements (≥20 mV), eliminating the need for type-II or type-III compensation networks. This simplifies design, reduces BOM count, and avoids stability tuning-confirmed in Section 8.3.1 and Figure 8-1 of the LM5013DDAR datasheet. The LM5013DDAR's architecture inherently adapts switching frequency to load and line changes without external compensation.

What is the purpose of the RON pin on the LM5013DDAR, and how is it configured?

The RON pin on the LM5013DDAR programs the high-side switch on-time using an external resistor to GND. Its value inversely scales with input voltage to maintain quasi-constant frequency; for example, 25 kΩ yields ~245 ns at 100 V. Equation 3 in the datasheet defines t_ON = 2.5 × R_RON/V_IN. The LM5013DDAR requires R_RON to be selected so minimum on-time exceeds 50 ns across the full VIN range-critical for high step-down ratios. Incorrect R_RON values cause frequency instability or failure to regulate.

Can the LM5013DDAR drive a pre-biased output during startup?

Yes, the LM5013DDAR supports monotonic start-up into pre-biased outputs, preventing reverse current flow and protecting downstream circuitry. This behavior is enabled by its COT architecture and internal soft-start ramp, which gradually increases duty cycle without forcing negative inductor current. Section 8.1 Overview and Figure 8-1 of the LM5013DDAR datasheet confirm this feature is implemented for safe operation in systems with hold-up capacitors or shared rails. The LM5013DDAR's ability to start into pre-biased loads is essential for hot-swap and redundant power applications.

What thermal performance can be expected from the LM5013DDAR in a standard 2-layer PCB layout?

In a standard 2-layer PCB with 1-in² 2-oz copper thermal pad connected to the exposed EP, the LM5013DDAR achieves a junction-to-board thermal resistance (R_θJB) of 9.5°C/W, allowing 3.5-A operation at up to +85°C ambient without forced airflow. Section 7.4 Thermal Information specifies R_θJA = 34.8°C/W for the SO PowerPAD™ DDA package. Derating curves in Figure 7-6 show RDSON increases only ~25% from 25°C to 125°C, confirming robust thermal performance. For full 3.5-A load at +105°C ambient, a 4-layer board with internal ground planes is recommended to maintain TJ < 150°C.