Analog Devices Inc./Maxim Integrated MAX5969DETE+T

Overview

MAX5969DETE+T from Maxim Integrated is an IEEE 802.3af/at-compliant powered device (PD) interface controller with integrated n-channel isolation power MOSFET, providing detection signature (24.9kΩ), 2-event classification support, and inrush current limiting (≤180mA) for PoE-powered IP phones, security cameras, and wireless access nodes.

For engineers reviewing the MAX5969DETE+T datasheet, MAX5969DETE+T pinout, MAX5969DETE+T application, or MAX5969DETE+T equivalent, key selection criteria include its 100V input absolute maximum rating, dual UVLO thresholds (VON = 35.4V, VOFF = 31V), thermal shutdown at +140°C, and seamless wall adapter switchover capability via WAD input.

Technical Context

The MAX5969DETE+T implements a four-mode state machine-detection (1.4–10.1V), classification (12.6–20V), mark event (falling <11.6V), and power mode (>35.4V)-with hardware-based 2-event classification signaling via 2EC current sink and automatic wall adapter priority arbitration when VWAD > 9V relative to RTN.

Its integrated isolation MOSFET features R_{ON_ISO} = 0.7Ω (T_J = +25°C), supports up to 880mA steady-state current limit, and includes foldback protection triggered at V_RTN ≥ 16.5V to reduce power dissipation during overload across VDD–RTN.

Key Specifications

Pinout & Package

Package: 16-pin, 5mm × 5mm thermally enhanced TQFN-EP with exposed pad (internally connected to VSS, must be externally soldered to PCB ground plane for thermal management).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar powered device interface applications.

Compared with LT4275IMS#PBF and TPS23753APWR, the MAX5969DETE+T uniquely integrates 2-event classification, wall adapter arbitration, and thermal foldback in a single 5mm × 5mm package-reducing solution size and eliminating firmware dependencies for mid-power (≤30W) PoE devices.

Availability

MAX5969DETE+T is available at Aetrix Electronics and suitable for IP phones, IP security cameras, wireless access nodes, and WiMAX base stations requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for MAX5969DETE+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

Maxim Integrated (now part of Analog Devices) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, communications, and consumer applications.

The MAX5969D product line delivers fully integrated, standards-compliant PoE powered device controllers targeting space-constrained, thermally demanding endpoints that require zero-firmware power management and dual-source reliability.

FAQ

What is the absolute maximum input voltage rating for the MAX5969DETE+T?

The MAX5969DETE+T has an absolute maximum input voltage rating of 100V across VDD to VSS. This allows robust operation in PoE systems with long cable runs or transient surges. The device operates continuously up to 60V and uses UVLO thresholds (VON = 35.4V, VOFF = 31V) to ensure stable power mode entry and exit. Exceeding 100V may cause permanent damage, per Absolute Maximum Ratings table.

How does the MAX5969DETE+T handle wall adapter detection and power source switchover?

The MAX5969DETE+T detects wall adapter presence via the WAD pin: when voltage between WAD and RTN exceeds 9V, it immediately disables the internal isolation MOSFET, asserts the 2EC current sink, and disables classification current. Switchover occurs autonomously-no microcontroller or external logic required. The MAX5969DETE+T gives wall adapter priority, ensuring uninterrupted operation during PoE interruption.

What is the purpose and behavior of the 2EC pin on the MAX5969DETE+T?

The 2EC pin on the MAX5969DETE+T serves dual functions: it signals 2-event classification detection for IEEE 802.3at Type 2 PSEs and acts as a wall adapter detect output. When a Type 2 PSE is detected, 2EC sinks 1.5mA and remains latched until VIN drops below the reset threshold (2.8–5.2V). When triggered by WAD, it sinks 1.5mA but is not latched-deasserting immediately upon WAD removal. This pin enables host system status monitoring without additional sensing circuitry.

Does the MAX5969DETE+T require external components for IEEE 802.3af/at compliance?

Yes-the MAX5969DETE+T requires three external passive components for full IEEE compliance: a 24.9kΩ detection resistor (RDET) between VDD and DET, a classification resistor (RCLS) between CLS and VSS (value selected per desired Class 0–5), and a minimum 68nF bypass capacitor between VDD and VSS. These components establish the detection signature, set classification current, and stabilize the input supply-no active components or firmware are needed.

What thermal protection mechanisms are implemented in the MAX5969DETE+T?

The MAX5969DETE+T incorporates junction temperature monitoring with thermal shutdown at +140°C and hysteresis release at +112°C. During overload, it also applies current-limit foldback when VRTN ≥ 16.5V-reducing the current limit from 800mA to ~300mA to lower MOSFET power dissipation. Both protections act independently: thermal shutdown disables the MOSFET, LED driver, and 2EC sink; foldback remains active in power mode to sustain partial operation under moderate overload.