Texas Instruments LM3495EVAL

Overview

LM3495EVAL from Texas Instruments is a fully assembled, four-layer evaluation module designed to validate and characterize the LM3495 synchronous buck controller in real-world 12 V input-to-1.2 V/10 A output power conversion applications. It supports input voltage range of 2.9 V to 18.0 V, operates at 500 kHz switching frequency, delivers up to 86% efficiency at 7 A load, and includes configurable SKIP/FPWM mode selection and ON/OFF enable control.

For engineers reviewing the LM3495EVAL datasheet, LM3495EVAL pinout, LM3495EVAL application, or LM3495EVAL equivalent, this board enables rapid validation of gate drive timing, current limit setting, output ripple performance, load transient response, and external clock synchronization for high-efficiency DC/DC converter designs.

Technical Context

The LM3495EVAL implements a fixed-frequency, current-mode synchronous buck controller using the LM3495 IC in TSSOP-16 package. It integrates dual MOSFET drive circuitry (HG/LG), adjustable current limit via R_LIM, and programmable switching frequency (500 kHz default) via R_FRQ. The board uses SO-8 and LFPAK footprints for Q1 (HAT2198R) and Q2 (HAT2165H), respectively.

It supports three operational modes: FPWM for forced continuous conduction, SKIP for light-load efficiency optimization, and TRACK for output voltage sequencing. Input power is applied via screw terminals; output is accessible through dedicated Vo/GND pads with low-inductance 100-nF ceramic capacitor (C_OX) for ripple measurement.

Key Specifications

Availability

LM3495EVAL is available at Aetrix Electronics and suitable for power supply validation, DC/DC converter reference design verification, and buck controller qualification requiring stable component supply and documented test methodology.

Supply support for LM3495EVAL 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 over 50 years of leadership in power conversion innovation.

The LM3495EVAL belongs to TI's Power Management Evaluation Modules product line, engineered to accelerate development of high-efficiency synchronous buck regulators for server, telecom, and industrial power systems.

FAQ

What is the primary function of the LM3495EVAL evaluation module?

The LM3495EVAL evaluation module is a ready-to-use hardware platform that demonstrates and validates the operation of the LM3495 synchronous buck controller IC. It enables engineers to evaluate key performance metrics-including efficiency, load transient response, output ripple, and gate drive behavior-under real operating conditions with user-configurable input voltage, output load, and control modes. The LM3495EVAL includes all necessary passives, MOSFETs, and interconnects to operate out-of-the-box.

Does the LM3495EVAL support external clock synchronization?

Yes, the LM3495EVAL supports external clock synchronization via the FREQ/SYNC pin. When an external clock signal is applied to the SYNC IN terminal, the DSYNC capacitor is removed and a 100-pF capacitor is placed at CSYNC to configure the LM3495 for slave mode operation. This allows precise timing alignment with system clocks in multi-rail power architectures. The LM3495EVAL schematic and layout accommodate this configuration without modification.

How is the output voltage set on the LM3495EVAL?

The output voltage on the LM3495EVAL is set by the resistor divider formed by R_FB1 (10 kΩ) and R_FB2 (10 kΩ), which establishes a 1.2 V nominal output per the LM3495's 0.6 V feedback reference. The FB pin connects to the midpoint of this divider, and the output voltage can be recalculated as V_OUT = 0.6 V × (1 + R_FB1/R_FB2). The LM3495EVAL provides solder pads for modifying these resistors to adjust V_OUT across different target voltages.

Can the LM3495EVAL be used to test different MOSFETs?

Yes, the LM3495EVAL features standardized SO-8 footprints for the high-side FET (Q1) and LFPAK-compatible footprints for the low-side FET (Q2), enabling direct replacement with other N-channel MOSFETs meeting voltage, R_DS(on), and gate charge requirements. The board includes test points for HG, LG, and SW nodes to monitor switching waveforms, and optional RC snubber pads (R_SNB/C_SNB) help dampen ringing when substituting faster or higher-capacitance devices. The LM3495EVAL's gate drive design supports typical gate drive currents up to 2 A peak.

What are the key thermal and layout features of the LM3495EVAL PCB?

The LM3495EVAL uses a four-layer FR4 PCB (62-mil thickness) with 1-oz copper on outer layers and 0.5-oz on internal planes, including a solid internal ground plane and split internal power plane to minimize noise coupling. High-current paths-including VIN, PGND, and SW-are routed with wide traces and multiple vias. Thermal relief is provided under MOSFET pads, and the layout places critical decoupling capacitors (C_INX, C_O1/C_O2, C_OX) adjacent to respective power pins to reduce loop inductance. The LM3495EVAL's layout adheres to TI's recommended practices for synchronous buck controllers.