Texas Instruments LM25116EVAL

Overview

LM25116EVAL from Texas Instruments is an evaluation board for the LM25116 synchronous buck controller IC, implementing emulated current mode control to deliver a regulated 5V/7A output from a 7V–42V input. It operates at 250kHz with 4-layer FR4 PCB construction (2 oz copper), supporting design validation of high-efficiency DC-DC converters in industrial power supplies and embedded systems.

For engineers reviewing the LM25116EVAL datasheet, LM25116EVAL setup procedure, LM25116EVAL performance waveforms, or LM25116EVAL BOM, this page provides verified board-level specifications, thermal and loading guidance, synchronization capability, short-circuit protection behavior, and TI-recommended airflow requirements for reliable bench evaluation.

Technical Context

The LM25116EVAL implements a non-isolated synchronous buck topology using the LM25116 HTSSOP-20EP controller, configured for fixed 5V output with adjustable soft-start and external synchronization via the SYNC pin. It supports both continuous and discontinuous conduction modes, selectable via JMP1 jumper.

Over-current protection is implemented with cycle-by-cycle current limiting set to ~11A, while VCCX test point enables auxiliary supply evaluation for higher-output-voltage configurations. Thermal management requires ≥200 LFM airflow during full-load operation at high input voltage.

Key Specifications

Availability

LM25116EVAL is available at Aetrix Electronics and suitable for industrial power supply development, embedded system prototyping, and automotive subsystem evaluation requiring stable component supply and documented TI reference design validation.

Supply support for LM25116EVAL 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 company specializing in analog, embedded processing, and power management technologies, with leadership in high-reliability industrial and automotive solutions.

The LM25116EVAL belongs to TI's Power Management Evaluation Platform family, designed to accelerate validation of wide-input synchronous buck controllers in real-world power conversion applications.

FAQ

What is the primary function of the LM25116EVAL evaluation board?

The LM25116EVAL evaluation board is a fully assembled, tested reference design that demonstrates the LM25116 synchronous buck controller in a 5V/7A power converter. It enables engineers to validate circuit performance-including efficiency, transient response, and protection features-without designing from scratch. The LM25116EVAL uses Emulated Current Mode Control and supports input voltages from 7V to 42V, making it ideal for rapid prototyping of industrial and transportation power supplies.

How do I configure the LM25116EVAL for synchronization with an external clock?

The LM25116EVAL provides a dedicated SYNC pin (TP5) that accepts an external TTL/CMOS clock signal to synchronize the 250kHz switching frequency. To enable synchronization, connect the external clock source to TP5 and ensure the LM25116 controller's internal oscillator is disabled per the SNVS509 datasheet. The LM25116EVAL schematic confirms direct routing of this signal to U1 Pin 19, and no additional hardware modification is required beyond the external connection.

What thermal management is required when operating the LM25116EVAL at full load?

At full 7A load and high input voltage (e.g., 42VIN), the LM25116EVAL's Si7850DP MOSFETs generate significant heat, requiring ≥200 LFM airflow to prevent thermal shutdown or reliability degradation. TI's AN-1617 explicitly states that prolonged operation without forced cooling will cause MOSFET overheating. The LM25116EVAL's thermal performance data (Figures 3–4) shows temperature rise exceeding safe limits without airflow, confirming mandatory fan use for sustained testing.

Does the LM25116EVAL support short-circuit protection, and how is it implemented?

Yes, the LM25116EVAL provides short-circuit protection through the LM25116's built-in cycle-by-cycle current limiting, which clamps output current to ~11A. For sustained short-circuit conditions, TI recommends installing capacitor C7 (≥1 µF) and diode D2 to reduce power dissipation and enable hiccup-mode recovery. This configuration is validated in Figure 7 of the LM25116EVAL user's guide and directly leverages the LM25116's fault-handling architecture.

Can the LM25116EVAL be used to evaluate different output voltages besides 5V?

No-the LM25116EVAL is factory-configured for fixed 5V output via resistor divider R3/R4 (3.74kΩ/1.21kΩ), and its feedback network is not user-adjustable without component replacement. While the underlying LM25116 controller supports programmable output voltages, the LM25116EVAL board itself lacks onboard potentiometer or jumper options for voltage reconfiguration. TI's documentation confirms the board delivers only 5V output unless modified per SNVS509 design guidelines.