Texas Instruments TPS2383PM

Overview

TPS2383PM from Texas Instruments is an IEEE 802.3af-compliant Power Sourcing Equipment Power Manager (PSEPM) for Ethernet-based power delivery. It manages up to eight PoE ports with programmable discovery, classification, and controlled 48-V power ramping via external N-channel MOSFETs. Key specs include 12-bit per-port current/voltage acquisition, dual-color LED drivers (L1–L8), I²C slave interface with 5-bit address selectability, and hardware FAULT interrupt (INTB). It targets mid-span injectors and PoE switches requiring precise port-level fault detection and EMI-controlled power-up.

For engineers reviewing the TPS2383PM datasheet, TPS2383PM pinout, TPS2383PM application, or TPS2383PM equivalent, this device supports PoE system design where per-port current monitoring (±1 mA resolution), UV/OV/OC fault response (<10 µs gate turn-off), isolated I²C communication via opto-coupler-compatible SDA_O, and 64-pin LQFP packaging are critical selection criteria.

Technical Context

The TPS2383PM implements a master sequencer architecture that cycles through eight independent port state machines, coordinating shared analog resources-including a 12-bit A/D converter, CR/CT/CINT timing network, and ramp control logic-to execute discovery (25-kΩ resistor + capacitive legacy detection), classification (17.5 V terminal voltage, 12-bit current measurement), and powered-mode monitoring. Each port uses dedicated analog sense paths (nP/nN, nRS, nG) and discrete gate drive outputs (nG pins) to control external low-side N-MOSFETs.

Its I²C interface operates as a slave with configurable 5-bit address (A1–A5), supports 400 kHz clock, and features separate SDA_I/SDA_O pins enabling galvanic isolation using optocouplers. Internal bias generation (V10 = 10 V, reference = 2.5 V) and three supply domains (V48: 44–57 V, V5: 5 V, VL: 3.3 V) enable operation with minimal external components while maintaining compliance with UL/IEC950 SELV safety requirements.

Key Specifications

Pinout & Package

The TPS2383PM is housed in a 64-pin LQFP package (PM suffix), with exposed thermal pad, RoHS-compliant lead finish, and 0.5 mm pitch. Pin functions are validated per TI SLUS559B datasheet revision July 2004.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS2383PM, TPS2384PWR extends port count and adds DAC configurability at the expense of A/D resolution, while MAX5980GTJ+ integrates gate drivers to shrink footprint but removes external FET optimization-making TPS2383PM optimal for high-reliability, thermally managed, 8-port PoE systems requiring precise telemetry.

Availability

TPS2383PM is available at Aetrix Electronics and suitable for PoE mid-span injectors, enterprise Ethernet switches, and industrial IoT gateways requiring stable component supply, long-term lifecycle support, and traceable sourcing for safety-critical infrastructure.

Supply support for TPS2383PM 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 company headquartered in Dallas, Texas, specializing in analog, embedded processing, and power management technologies for industrial, automotive, and communications markets.

The TPS2383PM belongs to TI's Power over Ethernet (PoE) PSE controller product line, designed specifically for scalable, standards-compliant Ethernet power infrastructure requiring programmable multi-port management and real-time telemetry.

FAQ

What is the maximum number of Ethernet ports the TPS2383PM can manage simultaneously?

The TPS2383PM is designed to manage up to eight independent Ethernet ports. Each port has dedicated analog sensing (nP/nN, nRS, nG), individual register sets for discovery/classification/power control, and status reporting via the I²C interface. The master sequencer cycles through all enabled ports, allocating shared resources like the 12-bit A/D converter and ramp control circuitry. This architecture enables full per-port visibility and control in dense PoE switch or injector applications.

Does the TPS2383PM require external MOSFETs, and why?

Yes, the TPS2383PM requires external N-channel MOSFETs connected to its nG (gate drive) and nN (return path) pins. It does not integrate power switches. This design allows system designers to select MOSFETs optimized for R_DS(on), thermal performance, and cost-critical for high-port-count systems where power dissipation must be minimized. The TPS2383PM provides high-voltage (up to 10 V) gate drive and fast fault turn-off (<7.5 µs) to ensure reliable switching of these external FETs.

How does the TPS2383PM support isolation between the 48-V PoE domain and the 3.3-V controller domain?

The TPS2383PM supports isolation via its dual SDA lines: SDA_I (input) and SDA_O (open-drain output). SDA_O is 48-V tolerant and can directly drive optocoupler LEDs using a series current-limiting resistor, enabling galvanic isolation of the I²C bus. This allows a ground-referenced microcontroller (e.g., MSP430) to communicate safely with the TPS2383PM while maintaining separation between the high-voltage PoE infrastructure and low-voltage control logic-meeting UL/IEC950 SELV requirements.

What is the role of the CR, CT, and CINT capacitors in the TPS2383PM circuit?

The CR capacitor sets the di/dt ramp rate for controlled power-up/down; CT and RT set the internal clock frequency (100–500 kHz) governing state machine timing and fault timers; CINT integrates the A/D converter input for precise resistance, current, and voltage measurements. All three capacitors are externally connected-CR to Pin 50 (AG2 referenced), CT to Pin 52 (RT referenced), and CINT to Pin 30 (RG referenced)-and their values (e.g., 0.1 µF CR, 100–470 pF CT, 0.033 µF CINT) are specified in SLUS559B to meet IEEE 802.3af timing and accuracy requirements.

Can the TPS2383PM power non-IEEE 802.3af devices, and how is this achieved?

Yes, the TPS2383PM supports non-compliant legacy devices via capacitive detection mode. When enabled, it uses its 12-bit A/D converter to measure the load's capacitive signature instead of relying solely on the 25-kΩ resistive discovery method. This avoids damage to non-PoE equipment (e.g., analog phones) while still allowing safe power delivery. Configuration is done via per-port registers, and the device maintains full fault protection (UV/OV/OC) regardless of detection mode-ensuring robust interoperability across mixed-device networks.