Quad, IEEE 802.3at/af PSE Controller for Power-over-Ethernet

The MAX5980A is a quad, power-sourcing equipment (PSE) power controller designed for use in IEEE® 802.3at/af-compliant PSE. This device provides powered device (PD) discovery, classification, current limit, and load disconnect detection. The device supports both fully automatic operation and software programmability. The device also supports new 2-event classification and Class 5 for detection and classification of high-power PDs. The device supports single-supply operation, provides up to 70W to each port (Class 5 enabled), and still provides high-capacitance detection for legacy PDs.

The device features an I²C-compatible, 3-wire serial interface, and is fully software configurable and programmable. The device provides instantaneous readout of port current and voltage through the I2C interface. The device’s extensive programmability enhances system flexibility, enables field diagnosis, and allows for uses in other, nonstandard applications.

The device is available in a space-saving, 32-pin TQFN (5mm x 5mm) power package and is rated for the automotive (-40°C to +105°C) temperature range.

Applications

* Midspan Power Injectors * Power-Sourcing Equipment (PSE) * PSE-ICM * Switches/Routers

* IEEE 802.3at/af Compliance Enables PD Discovery, Classification, Current Limit, and Load-Disconnect Detection

* Provides Interoperability with Any Compliant PD

* Two-Point Slope Measurement Verifies the Device Connected to the Port

* Appropriate Settling Times Implemented to Reject 50Hz/60Hz Power-Line Noise Coupling

* High Power Beyond IEEE 802.3at/af Standard Supported with Additional Classification (Class 5) when Needed

* IEEE Power-over-Ethernet (PoE) Transmission Facilitates Signaling Between Power-Sourcing Equipment (PSE) and Powered Devices (PDs)

* Single-Supply Operation Provides Up to 70W per Port for PSE Applications, Allowing High-Capacitance Detection for Legacy PDs

* 0.25Ω Current-Sensing Resistor Helps Eliminate Power Losses when Sensing High Currents

* Software-Configurable/Programmable Registers through I²C-Compatible, 3-Wire Serial Interface Produces Instantaneous Readout of Port Current and Voltage through 9-Bit Port Current and Voltage Monitoring

* Supports DC Load-Removal Detection

* Saves Space with Thermally Efficient Power Package

* Available in a 32-Pin (5mm × 5mm) TQFN with an Exposed Pad for Heat Dissipation