Analog Devices Inc./Maxim Integrated MAX26405AFODY+T

Overview

MAX26405AFODY+T from Analog Devices is a fully integrated, synchronous Silent Switcher® buck converter delivering up to 5A continuous output current with 3V–36V input range and fixed 5V output. It features 2.1MHz switching frequency, 10μA no-load quiescent current in skip mode, PGOOD monitoring, and 99% dropout operation-designed for automotive infotainment power rails and industrial 24V point-of-load regulation.

For engineers reviewing the MAX26405AFODY+T datasheet, MAX26405AFODY+T pinout, MAX26405AFODY+T application, or MAX26405AFODY+T equivalent, key selection criteria include its FC2QFN-17 package thermal performance (θJB = 10.2°C/W), ±1% output accuracy in FPWM mode, spread-spectrum EMI reduction, dual-phase VEA-based current sharing, and compatibility with 0.1μF BST capacitor and 2.2μF BIAS decoupling.

Technical Context

This device implements average current-mode control with internal slope compensation, enabling robust noise immunity and stable operation across wide VIN/VOUT ratios. Its 33ns minimum on-time supports high step-down ratios (e.g., 24V-to-5V at 2.1MHz) without pulse-skipping artifacts.

The MAXQ® power architecture delivers precise transient response via high phase-margin loop design and integrates a 1.8V BIAS LDO that auto-switches from SUP to OUT after startup. Dual-phase operation uses SYNCOUT (180° out-of-phase) and shared VEA for dynamic current balancing-requiring forced-PWM mode and separate FB dividers per phase when adjustable outputs are used.

Key Specifications

Pinout & Package

Package: 3.5mm × 3.75mm, 17-pin FC2QFN (package code F173A3FY+6), exposed thermal pad, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck converter applications.

Compared with LM61480RQR and TPS54560RGTT, the MAX26405AFODY+T offers superior EMI performance via integrated Silent Switcher layout and spread-spectrum modulation, tighter output accuracy (±1% vs. ±1.5%), and native dual-phase support-making it optimal for space-constrained, noise-sensitive automotive and medical designs requiring 5A at 5V.

Availability

MAX26405AFODY+T is available at Aetrix Electronics and suitable for automotive infotainment power supplies, industrial PLC I/O modules, telecom base station bias rails, and medical imaging sensor interfaces requiring stable component supply across extended temperature and voltage ranges.

Supply support for MAX26405AFODY+T 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, serving precision instrumentation, industrial automation, communications, and automotive markets.

The MAX26404/MAX26405/MAX26406 family was designed specifically for high-density, low-EMI point-of-load conversion in automotive and industrial environments where input transients, thermal constraints, and regulatory EMI limits demand integrated, robust solutions.

FAQ

What is the output voltage configuration of the MAX26405AFODY+T?

The MAX26405AFODY+T is factory-configured for fixed 5V output. This is achieved by internally connecting the FB pin to the 1.8V BIAS rail-no external resistor divider is required. The datasheet confirms this variant in the ordering information table and specifies ±1% output accuracy in FPWM mode at no load. For other voltages, the MAX26404 or MAX26406 variants with adjustable FB pin must be selected.

Does the MAX26405AFODY+T support dual-phase operation, and what is required to implement it?

Yes, the MAX26405AFODY+T supports dual-phase operation using its SYNCOUT and VEA pins. To configure dual-phase, one device acts as controller (SYNC pulled high to BIAS) and the other as target (SYNC tied to BIAS, SYNCOUT connected to controller's SYNCOUT). The controller's VEA pin connects to the target's VEA pin to enable dynamic current sharing. Both devices must operate in forced-PWM mode; skip mode disables SYNCOUT and prevents synchronization.

What thermal performance can be expected from the MAX26405AFODY+T in a real PCB layout?

In a 4-layer evaluation board layout, the MAX26405AFODY+T achieves θJB = 10.2°C/W and θJA = 28.9°C/W. With 5A load and 125°C maximum junction temperature, this allows ~75°C ambient operation before thermal shutdown-sufficient for sealed automotive enclosures. The FC2QFN package's exposed thermal pad must be soldered to a minimum 100mm² copper pour with ≥4 thermal vias to achieve these values; inadequate thermal relief increases junction temperature by >20°C.

How does the MAX26405AFODY+T handle input undervoltage and overvoltage conditions?

The MAX26405AFODY+T includes SUP undervoltage lockout (UVLO) with rising threshold of 3.025V and falling threshold of 2.725V (2.725V–3.025V hysteresis), preventing erratic startup during battery brownouts. Absolute maximum SUP rating is +42V, and the device survives transient overvoltages ≤50ns beyond this limit under normal load. For sustained 36V operation-common in 24V industrial systems-the internal high-side MOSFET's 45mΩ RDS(ON) and thermal design ensure reliable performance without derating.

Can the MAX26405AFODY+T be synchronized to an external clock, and what are the valid frequency ranges?

Yes, the MAX26405AFODY+T accepts external synchronization via the SYNC pin. When configured for 2.1MHz internal frequency, it locks to external clocks between 1.7MHz and 2.6MHz. For 400kHz operation, the valid sync range is 360kHz to 600kHz. The device synchronizes within two cycles and reverts to internal clock if sync signal is absent for >2 cycles. Spread-spectrum modulation is disabled during external sync, but any modulation present on the driving clock passes through unfiltered.