Texas Instruments LM3478EVAL/NOPB

Overview

LM3478EVAL/NOPB from Texas Instruments is an evaluation board designed to demonstrate the LM3478 current-mode, low-side N-channel FET controller in a boost topology. It delivers 12 V at up to 1.5 A from a 5 V input, operates at 1 MHz switching frequency, and features adjustable output voltage via feedback resistors (V_FB = 1.26 V). The board supports rapid prototyping of high-efficiency DC-DC boost converters for industrial and embedded power applications.

For engineers reviewing the LM3478EVAL/NOPB datasheet, LM3478EVAL/NOPB pinout, LM3478EVAL/NOPB application, or LM3478EVAL/NOPB equivalent, this board enables hands-on validation of LM3478-based boost converter performance-including efficiency, load regulation, startup behavior, and transient response-under real-world conditions with minimal external components.

Technical Context

The LM3478EVAL/NOPB implements a fixed-frequency current-mode control architecture using the LM3478MM IC (8-pin SON package), supporting continuous conduction mode (CCM) operation. Its schematic integrates a 1.8 µH shielded inductor (XAL6030-182ME), 4.4 mΩ NexFET™ Q1 (CSD16323Q3), and Schottky diode (PMEG3030EP) to minimize conduction losses and optimize thermal performance.

Input voltage is constrained to 4.5–5.5 V via onboard edge connector terminals, while output voltage is factory-set to 12 V using R_FBT = 86.6 kΩ and R_FBB = 10.2 kΩ. The board includes test points for VIN, VOUT, ISEN, COMP, and SW nodes, enabling oscilloscope-based waveform analysis of switching node voltage, inductor current, and loop dynamics.

Key Specifications

Availability

LM3478EVAL/NOPB is available at Aetrix Electronics and suitable for industrial power supply design, embedded DC-DC conversion, and automotive subsystem prototyping requiring stable component supply and TI-validated reference performance.

Supply support for LM3478EVAL/NOPB 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 headquartered in Dallas, Texas, specializing in analog, embedded processing, and power management technologies with over 90 years of innovation in electronics design tools and silicon solutions.

The LM3478EVAL/NOPB belongs to TI's Power Management Evaluation Modules product line, engineered specifically to accelerate development of high-efficiency, current-mode DC-DC controllers for boost, flyback, and SEPIC topologies in space-constrained applications.

FAQ

What is the primary function of the LM3478EVAL/NOPB?

The LM3478EVAL/NOPB is a Texas Instruments evaluation board that demonstrates the LM3478 current-mode, low-side N-channel FET controller operating in boost configuration. It provides a fully assembled, tested platform to validate key performance metrics-including efficiency, load regulation, startup behavior, and transient response-for designs targeting 12 V output from a 5 V input source. The LM3478EVAL/NOPB is not a finished product but a development tool intended for R&D use only.

Can the output voltage of the LM3478EVAL/NOPB be adjusted, and how?

Yes, the output voltage of the LM3478EVAL/NOPB can be adjusted from the default 12 V by modifying the feedback resistor divider network. Using the formula V_OUT = 1.26 V × (1 + R_FBT/R_FBB), users replace R_FBT (86.6 kΩ) and/or R_FBB (10.2 kΩ) with precision 1% resistors. The LM3478EVAL/NOPB schematic and bill of materials identify designated pads for these components, enabling straightforward reconfiguration without PCB modification.

What are the input power requirements for the LM3478EVAL/NOPB?

The LM3478EVAL/NOPB requires a regulated DC input between 4.5 V and 5.5 V, delivered through its 30-pin edge connector (EDAC 307-020-500-202). The board is not designed for wide-input-range operation; exceeding 5.5 V risks damage to the LM3478MM controller and associated components. Input current capability must support ≥1.8 A peak to accommodate full 1.5 A output load with typical boost converter inefficiencies.

Does the LM3478EVAL/NOPB support flyback or SEPIC topologies out of the box?

No, the LM3478EVAL/NOPB is configured exclusively for boost topology demonstration, as confirmed by its schematic, layout, and user guide. While the underlying LM3478MM IC supports flyback and SEPIC configurations, implementing those requires significant hardware changes-including transformer or coupled inductor substitution, revised snubber networks, and modified feedback paths-which are not supported by the LM3478EVAL/NOPB's fixed component selection and PCB routing.

Is the LM3478EVAL/NOPB FCC-certified for emissions compliance?

No, the LM3478EVAL/NOPB is not FCC-certified. Per TI's Standard Terms and Conditions for Evaluation Modules, it is intended solely for R&D use in controlled environments and lacks final product-level EMC qualification. Users must perform their own emissions testing if integrating LM3478-based designs into commercial products. The LM3478EVAL/NOPB documentation explicitly states it may not be resold or marketed as a finished device without obtaining required FCC authorizations.