Analog Devices Inc. EVAL-LT7171-AZ

Overview

EVAL-LT7171-AZ from Analog Devices is a dual-phase evaluation board for the LT7171 16V monolithic synchronous step-down regulator with digital power system management, delivering up to 40A at 1.0V output, operating from 2.9V–16V input, and featuring Silent Switcher® architecture for low EMI in high-density power applications such as server VRMs and telecom POL converters.

For engineers reviewing the EVAL-LT7171-AZ datasheet, EVAL-LT7171-AZ pinout, EVAL-LT7171-AZ application, or EVAL-LT7171-AZ equivalent, this board enables rapid validation of LT7171's PMBus/I²C programmability, transient response (25ns min on-time), efficiency (87.5% @12V/20A), NVM configuration storage, and parallel-phase scalability up to four phases.

Technical Context

The EVAL-LT7171-AZ implements two LT7171RV ICs in parallel, each configured as a single-phase valley current-mode controller with 1MHz switching frequency, 25ns minimum on-time, and integrated MOSFET drivers supporting external high-efficiency power stages. It uses controlled on-time modulation for fast load-step response and stable regulation at low output voltages.

Digital power management is enabled via PMBus/I²C interface through J7 header, supporting real-time telemetry (voltage, current, temperature), fault logging, sequencing control, and NVM-based configuration persistence (up to three writes). The board powers up autonomously using factory-default NVM settings without host communication.

Key Specifications

Availability

EVAL-LT7171-AZ is available at Aetrix Electronics and suitable for server power delivery, telecom point-of-load conversion, and FPGA/ASIC core voltage regulation requiring stable component supply, rapid prototyping capability, and production-ready digital power validation.

Supply support for EVAL-LT7171-AZ 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

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Wilmington, MA, with deep expertise in power management, signal chain, and RF technologies.

The LT7171 product line delivers high-current, digitally managed DC/DC conversion for demanding infrastructure applications where efficiency, EMI compliance, and remote configurability are critical-targeting data center, networking, and high-end computing systems.

FAQ

What is the primary function of the EVAL-LT7171-AZ evaluation board?

The EVAL-LT7171-AZ evaluation board is designed to demonstrate and validate the performance of the LT7171 dual-phase synchronous step-down regulator. It provides a fully assembled, tested platform for evaluating 40A output at 1.0V, Silent Switcher® EMI reduction, PMBus/I²C programmability, and digital telemetry-enabling engineers to verify functionality before integrating the LT7171 into custom designs. The board ships with default NVM settings for immediate power-up without host communication.

Does the EVAL-LT7171-AZ support multi-phase expansion beyond two phases?

Yes, the EVAL-LT7171-AZ reserves space for up to four LT7171 ICs, allowing evaluation of four-phase parallel operation delivering up to 80A. The schematic and layout include provisions for populating two additional LT7171RV positions (U3 and U4), with shared clock (SHARE_CLK), synchronization (SYNC), and current-sharing circuitry pre-routed per the LT7171 data sheet guidelines for phase interleaving and thermal balancing.

Which software and hardware are required to configure the EVAL-LT7171-AZ via PMBus?

To configure the EVAL-LT7171-AZ via PMBus, users must install LTpowerPlay software on a Windows PC and connect the board using Analog Devices' DC1613A USB-to-SMBus/PMBus dongle. The J7 12-pin header provides the physical interface. LTpowerPlay enables real-time read/write of registers-including VOUT_COMMAND, current limits, fault thresholds, and sequencing parameters-and supports saving configurations to the LT7171's onboard NVM for autonomous startup.

How does the EVAL-LT7171-AZ achieve low EMI performance?

The EVAL-LT7171-AZ achieves low EMI through the LT7171's integrated Silent Switcher® architecture, which employs symmetrical hot-loop layout, integrated bypass capacitors, and optimized internal gate drive timing to minimize magnetic field radiation. The board's PCB stack-up and component placement follow strict layout guidelines from the LT7171 data sheet, including short, symmetric power loops and dedicated ground planes-verified by typical output ripple of <1mVpp at 1MHz shown in Figure 5.

Can the EVAL-LT7171-AZ operate without connecting to a PC or PMBus host?

Yes, the EVAL-LT7171-AZ operates autonomously without any PC or PMBus connection. It boots using factory-programmed NVM settings to deliver 1.0V at up to 40A, with default switching frequency (1MHz), current limit, and protection thresholds. This allows immediate functional verification of power delivery, efficiency, and transient response-making it ideal for lab bench testing, production line validation, or environments where host communication is unavailable.