Analog Devices Inc./Maxim Integrated MAX20796AGFB+T

Overview

MAX20796AGFB+T from Analog Devices is a dual-phase, PMBus-compliant integrated buck regulator delivering up to 60A from 4.5V–16V input, with 0.5V–5.5V programmable output, fixed-frequency peak-current-mode control, and integrated linear regulators for single-supply operation-designed for point-of-load regulation in high-density server and telecom power systems.

For engineers reviewing the MAX20796AGFB+T datasheet, MAX20796AGFB+T pinout, MAX20796AGFB+T application, or MAX20796AGFB+T equivalent, key selection criteria include its two-phase interleaved architecture, 35-pin FC2QFN package, PMBus 1.3 interface, ±0.8% output voltage accuracy, and support for coupled inductors to minimize output capacitance and thermal stress.

Technical Context

The MAX20796AGFB+T implements a multiphase peak-current-mode control architecture with differential remote sensing (SNSP/SNSN), integrated loop compensation, and lossless current sensing per phase. It supports both coupled and discrete inductor topologies, with 180° phase shift in native dual-phase mode and 120° when extended to three-phase via external power stage.

Its control loop includes dual PI stages-one for voltage error (VERR → PI_V) and one for current-loop error (VIDES → PI_I)-combined with slope compensation and OCR-based current balancing. Startup features monotonic ramping, prebias tolerance up to VOUT_COMMAND, and RESTORE-triggered voltage reversion to pin-strapped setpoint.

Key Specifications

Pinout & Package

The MAX20796AGFB+T is housed in a 35-pin, 4mm × 10.5mm, 0.5mm pitch FC2QFN package with exposed thermal pad for enhanced heat dissipation in high-power-density applications.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-phase PMBus buck regulator applications.

Compared with MP2960A-AEC1 and ISL91302B, the MAX20796AGFB+T uniquely combines server-grade PMBus 1.3 telemetry, RESTORE-triggered voltage recovery, and seamless scalability to 90A via external power stage-making it optimal for cloud infrastructure where remote monitoring, firmware-updatable margins, and rapid fault recovery are required.

Availability

MAX20796AGFB+T is available at Aetrix Electronics and suitable for server motherboard designs, 5G baseband units, and enterprise storage controllers requiring stable component supply, long-term lifecycle assurance, and full PMBus interoperability.

Supply support for MAX20796AGFB+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, headquartered in Wilmington, MA.

The MAX20796AGFB+T belongs to Analog Devices' Power Management portfolio, specifically engineered for high-efficiency, digitally controlled point-of-load regulation in datacenter and communications infrastructure where density, telemetry, and reliability are critical.

FAQ

What is the maximum output current supported by the MAX20796AGFB+T in standalone dual-phase mode?

The MAX20796AGFB+T delivers up to 60A continuous output current in native dual-phase configuration, validated under thermal conditions of TA = +55°C with 200LFM airflow. This rating assumes proper PCB layout, adequate copper pour, and use of recommended coupled inductors and output capacitors per the MAX20796CL2EVKIT# reference design. The MAX20796AGFB+T achieves this with peak efficiency of 92% at 12V input and 1V output.

Does the MAX20796AGFB+T support prebias startup, and what is the maximum allowable prebias voltage?

Yes, the MAX20796AGFB+T supports monotonic prebias startup. In two-phase mode, it safely starts regulation even when the output is precharged up to the target VOUT_COMMAND voltage. This capability eliminates reverse current flow and ensures clean power-up in systems with shared output buses or hot-swap controllers. The MAX20796AGFB+T implements internal current limiting and phase alignment to maintain control throughout the ramp, as confirmed in Figure 4 of the datasheet.

How does the RESTORE pin function on the MAX20796AGFB+T, and what is its deglitch timing?

The RESTORE pin on the MAX20796AGFB+T provides hardware-triggered reversion of the output voltage to the pin-strapped value set by the PGMA resistor. A falling edge on RESTORE initiates immediate voltage transition at the same slew rate used during soft-start. To prevent false triggering from noise, the MAX20796AGFB+T incorporates a 10µs deglitch filter on this pin, as specified in the Electrical Characteristics table on page 5 of the datasheet. This ensures robust operation in electrically noisy server backplane environments.

Can the MAX20796AGFB+T operate with only the VDDH supply, or is an external VLDOIN source required?

The MAX20796AGFB+T can operate with only the VDDH supply connected to VLDOIN-enabling true single-rail operation. However, for optimal thermal performance, Analog Devices recommends powering VLDOIN from an external 3.3V source or using the EB pin to drive an external nFET (e.g., SQA410EJ-T1_GE3) to generate an efficient 3V supply. This reduces internal LDO power dissipation, lowers junction temperature, and improves full-load efficiency by up to 2% compared to VLDOIN = VDDH operation.

What package type and thermal characteristics define the MAX20796AGFB+T's mechanical integration?

The MAX20796AGFB+T uses a 35-pin FC2QFN package measuring 4mm × 10.5mm with 0.5mm pitch and an exposed thermal pad. Its thermal resistance is θJA = 32.9°C/W (JEDEC standard) and θJC = 0.20°C/W, enabling direct thermal coupling to heatsinks or inner-layer copper planes. The land pattern (90-100044) and outline (21-100023) are documented on analog.com/packages, ensuring reliable reflow and mechanical stability in high-vibration telecom chassis.