Texas Instruments LM3671MF-1.8EV

Overview

LM3671MF-1.8EV from Texas Instruments is an evaluation board for the LM3671 step-down DC-DC converter IC, configured with a fixed 1.8 V output, 2.2 µH inductor, 4.7 µF input capacitor, and 10 µF output capacitor. It supports 2.7–5.5 V input, delivers up to 600 mA load current, and demonstrates automatic PWM/PFM mode switching in SOT23-5 package layout. Used for rapid validation of power supply designs in portable electronics.

For engineers reviewing the LM3671MF-1.8EV datasheet, LM3671MF-1.8EV pinout, LM3671MF-1.8EV application, or LM3671MF-1.8EV equivalent, this page provides verified board-level specifications, layout insights, component BOM, operating conditions, and TI-recommended bench setup practices - all specific to the 1.8 V fixed-output SOT23-5 evaluation configuration.

Technical Context

The LM3671MF-1.8EV implements a synchronous buck topology using an internal PFET high-side switch and NFET synchronous rectifier, enabling >90% peak efficiency at medium loads. It operates across –30°C to +85°C ambient and integrates feedback resistors internally for 1.8 V regulation (V_FB = 0.5 V).

Automatic mode transition between PWM (for low-noise, high-load stability) and PFM (for ultra-low quiescent current <16 µA at light load) is handled without external control. The board's layout follows TI's recommended thermal and EMI mitigation practices for SOT23-5 DC-DC converters, including dedicated ground planes and minimized high-di/dt loop area.

Key Specifications

Availability

LM3671MF-1.8EV is available at Aetrix Electronics and suitable for portable medical sensors, battery-powered IoT nodes, and low-power microcontroller power rails requiring stable component supply, fast design iteration, and TI-validated reference performance.

Supply support for LM3671MF-1.8EV 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, delivering analog and embedded processing solutions for industrial, automotive, and personal electronics markets.

The LM3671 product line targets space-constrained, battery-operated applications requiring high-efficiency, low-quiescent-current DC-DC conversion with minimal external components - specifically designed for portable consumer and wearable devices.

FAQ

What is the purpose of the LM3671MF-1.8EV evaluation board?

The LM3671MF-1.8EV evaluation board is a fully assembled, tested platform for validating the LM3671 1.8 V fixed-output step-down converter in SOT23-5 packaging. It enables immediate functional verification, efficiency measurement, and transient response analysis without custom PCB design. Engineers use the LM3671MF-1.8EV to confirm voltage regulation accuracy, load step behavior, and thermal performance before integrating the LM3671 into end equipment.

Does the LM3671MF-1.8EV support adjustable output voltages?

No - the LM3671MF-1.8EV is configured exclusively for fixed 1.8 V output. Its onboard LM3671 IC has internal feedback resistors; no external R1/R2 network is populated. To evaluate adjustable operation, users must select the LM3671MF-ADJ variant and modify the feedback divider per TI's AN-1395 guidelines. The LM3671MF-1.8EV does not include solder pads or jumpers for output voltage reconfiguration.

What input capacitance is used on the LM3671MF-1.8EV, and why?

The LM3671MF-1.8EV uses a 4.7 µF X5R ceramic capacitor (TDK C2012X5R0J475K, 0805, 6.3 V) at the VIN node. This value balances high-frequency noise suppression, low ESR, and physical size constraints while maintaining stability under 600 mA load steps. TI specifies this capacitance as optimal for minimizing input voltage ripple and preventing undershoot during high di/dt switching events on the LM3671MF-1.8EV.

Can the LM3671MF-1.8EV be powered directly from a bench supply?

Yes, but TI mandates a 100 µF tantalum capacitor across the bench supply's VIN/GND terminals to suppress input voltage spikes caused by cable inductance. The LM3671MF-1.8EV's enable pin must remain below 0.4 V until VIN reaches ≥2.7 V; premature EN assertion risks latch-up or damage. Always ramp VIN first, then assert EN - a sequence enforced in the LM3671MF-1.8EV's test procedure.

What are the key layout features of the LM3671MF-1.8EV?

The LM3671MF-1.8EV employs a compact two-layer PCB with dedicated power and ground planes, minimized SW-to-GND loop area (<20 mm²), and thermal vias under the SOT23-5 pad to enhance heat dissipation. Input/output capacitors are placed adjacent to their respective pins, and the 2.2 µH inductor is oriented to reduce magnetic coupling. These layout choices directly reflect TI's recommendations in SNVA122F to ensure EMI compliance and stable operation of the LM3671MF-1.8EV.