Texas Instruments TPS2383PMG4

Overview

TPS2383PMG4 from Texas Instruments is an IEEE 802.3af-compliant Power Sourcing Equipment (PSE) power manager IC for Ethernet-based PoE mid-span injectors and switches. It manages up to eight PoE ports with programmable discovery, classification, and controlled 48-V power delivery, featuring 12-bit per-port current/voltage acquisition, dual-color LED status drivers, and hardware FAULT interrupt. It operates across 44–57 V input and supports opto-coupled I²C isolation.

For engineers reviewing the TPS2383PMG4 datasheet, TPS2383PMG4 pinout, TPS2383PMG4 application, or TPS2383PMG4 equivalent, key selection considerations include its 64-pin LQFP package, external N-channel MOSFET gate drive capability, 25-kΩ two-point resistor discovery, capacitive legacy load detection, and I²C slave interface with 5-bit address selectability for multi-device bus scalability.

Technical Context

The TPS2383PMG4 implements a master sequencer architecture that cycles through eight independent port state machines, coordinating shared analog resources-including a 12-bit A/D converter, ramp control (CR/CT/CINT), and discovery/classification voltage loops-across all ports. Each port uses dedicated analog sensing paths (nP/nN, nRS, RD) and high-voltage gate drivers (nG) for external N-MOSFET control.

Its I²C interface operates at up to 400 kHz with opto-coupler-compatible SDA_O output, while internal timing relies on RT-biased bias currents and CT/CR capacitor networks. Fault handling includes UVLO (28–40 V), port overvoltage (51–55 V), undervoltage (40–44 V), and overload detection with 50–100 ms timeout, all triggering hardware INTB assertion and controlled gate turn-off.

Key Specifications

Pinout & Package

The TPS2383PMG4 is housed in a 64-pin LQFP (PM) package with exposed thermal pad, optimized for thermal management in multi-port PoE systems. Pin functions are fully defined per TI SLUS559B Rev. July 2004.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PoE PSE management applications.

Compared with TPS2383PMG4, the TPS2384PMG4 reduces external component count by integrating the 10-V analog supply, while the MAX5980DETI+ extends operational temperature range and adds integrated hot-swap protection-making both alternatives suitable for specific design constraints but not drop-in replacements without layout or firmware updates.

Availability

TPS2383PMG4 is available at Aetrix Electronics and suitable for PoE mid-span injectors, Ethernet switches, and industrial IoT gateways requiring stable component supply, long-term lifecycle support, and traceable sourcing for production programs.

Supply support for TPS2383PMG4 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

Texas Instruments is a global semiconductor leader delivering analog, embedded processing, and connectivity solutions for industrial, automotive, and communications markets.

The TPS2383PMG4 belongs to TI's Power over Ethernet (PoE) PSE portfolio, designed specifically for scalable, standards-compliant Ethernet power infrastructure in enterprise and industrial networking equipment.

FAQ

What is the primary function of the TPS2383PMG4 in a PoE system?

The TPS2383PMG4 serves as a programmable Power Sourcing Equipment (PSE) power manager IC that discovers, classifies, and safely delivers 48-V power to IEEE 802.3af-compliant Powered Devices (PDs) across up to eight Ethernet ports. It implements full compliance logic-including two-point 25-kΩ discovery, classification current measurement, and controlled di/dt ramping-while providing real-time per-port monitoring via its 12-bit A/D converter. The TPS2383PMG4 requires external N-channel MOSFETs for power switching and integrates all control, protection, and communication functions needed for robust PoE infrastructure.

Does the TPS2383PMG4 support legacy (non-802.3af) device detection?

Yes, the TPS2383PMG4 supports capacitive detection mode for identifying legacy or non-compliant loads. In this mode, the internal A/D converter measures the load's capacitive signature instead of relying on resistive discovery, preventing potential damage from standard 25-kΩ probing. This feature is enabled via register configuration and allows safe power delivery to older or custom-powered devices that lack IEEE 802.3af signature resistors. The TPS2383PMG4 does not require external circuitry to activate this capability-it is fully implemented in analog front-end and firmware-controlled state machines.

How does the TPS2383PMG4 handle fault conditions such as overvoltage or overcurrent?

The TPS2383PMG4 detects overvoltage (51–55 V), undervoltage (40–44 V), and overcurrent (>375 mA average or >425 mA peak) on each port using dedicated analog comparators and current-sense amplifiers. Upon fault detection, it immediately discharges the corresponding gate driver (nG) via a low-R_ON internal switch, disconnecting the external N-MOSFET within 7.5 µs. Simultaneously, it asserts the open-drain INTB pin and updates the per-port fault status register. The TPS2383PMG4 also implements configurable timers-for example, 50–100 ms overload timeout-and supports automatic retry or latched shutdown based on register settings. All fault responses are hardware-automated and do not rely on host processor intervention.

Can the TPS2383PMG4 operate with galvanic isolation between the controller and PoE ports?

Yes, the TPS2383PMG4 supports galvanic isolation via its opto-coupler compatible SDA_O pin, which is a high-voltage open-drain output capable of directly driving opto-LEDs from the +48-V bus with only an external current-limiting resistor. When paired with SCL_I and SDA_I inputs referenced to the controller side, this enables full I²C isolation without level shifters. The TPS2383PMG4 also provides separate analog (AG1/AG2) and digital (DG) ground pins, allowing clean partitioning of isolated domains. This architecture ensures noise immunity and safety compliance in applications like industrial switches where controller and PoE port grounds must remain separated.

What package type and thermal characteristics does the TPS2383PMG4 use?

The TPS2383PMG4 is packaged in a 64-pin LQFP (PM) with exposed thermal pad, specified for operation from 0°C to 70°C junction temperature. Its thermal design leverages the exposed pad for enhanced heat dissipation-TI recommends soldering the pad to a large copper pour connected to internal ground planes. The device draws 5–10 mA quiescent current in powered mode across all ports, minimizing self-heating. Absolute maximum ratings include 65 V on V48 and 12 V on gate drivers, with internal thermal shutdown not explicitly specified in SLUS559B; system-level thermal management must therefore rely on PCB layout, airflow, and ambient derating per application requirements. The TPS2383PMG4 does not integrate a thermal sensor or reporting register.