Texas Instruments TPS2373-3RGWR

Overview

TPS2373-3RGWR from Texas Instruments is a IEEE 802.3bt-compliant Type-3 Powered Device (PD) interface IC with integrated 0.3-Ω hot-swap MOSFET, 1.85-A current limit, and advanced DC-DC startup control. It delivers up to 60 W at PD input (51 W after 100-m CAT5 cable loss) and supports PoE++ PSEs in security cameras, multiband access points, and VoIP telephones.

For engineers reviewing the TPS2373-3RGWR datasheet, TPS2373-3RGWR pinout, TPS2373-3RGWR application, or TPS2373-3RGWR equivalent, key selection criteria include its 1.85-A RTN current limit, 0.3-Ω rDS(on), -40°C to 125°C junction temperature range, automatic MPS generation, and VQFN-20 package compatibility with thermal pad grounding.

Technical Context

The TPS2373-3RGWR implements full IEEE 802.3bt Type-3 PD functionality: detection (56.5 µA typical DEN current), two-event hardware classification (programmable via CLSA/CLSB resistors), and inrush limiting (200 mA typical, 78–87 ms delay). Its internal 0.3-Ω MOSFET handles continuous 1.85-A load current with foldback protection triggered above 14.5 V on RTN.

Advanced startup logic generates a controlled VC_OUT bias supply (13.5–15 V) for downstream PWM controllers, reducing required bulk capacitance and enabling long soft-start periods. Automatic MPS uses AMPS_CTL and MPS_DUTY pins to generate pulsed current (5.4%, 8.1%, or 12.5% duty cycle) compliant with Type 1–4 PSEs without external timing components.

Key Specifications

Pinout & Package

The TPS2373-3RGWR is housed in a 5.00 mm × 5.00 mm VQFN-20 package with exposed thermal pad (connected to VSS). Pin 1 is top-left corner (VDD), pin 20 is bottom-right (NC); thermal pad must be soldered to PCB ground plane for thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PoE PD interface applications.

Compared with TPS2373-3RGWR, TPS2372-3RGWR offers lower BOM count but sacrifices MPS adaptability and startup simplification, while MAX5984DEWI+ trades integrated bias and tighter current limit for smaller package and legacy compatibility - all three require VQFN-20 layout but differ significantly in system-level integration effort.

Availability

TPS2373-3RGWR is available at Aetrix Electronics and suitable for security cameras, multiband access points, and VoIP telephones requiring stable component supply across extended temperature ranges and PoE++ interoperability.

Supply support for TPS2373-3RGWR 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 specializing in analog and embedded processing technologies, with leadership in power management and interface solutions.

The TPS2373 product line delivers fully integrated IEEE 802.3bt Type-3/4 PD interfaces targeting high-reliability, thermally demanding PoE-powered equipment such as surveillance systems and wireless infrastructure.

FAQ

What is the maximum continuous current supported by the TPS2373-3RGWR?

The TPS2373-3RGWR supports a typical continuous current of 1.85 A through its internal MOSFET, with a minimum guaranteed current limit of 1.55 A and maximum of 2.2 A across temperature and process variation. This enables reliable 60-W Type-3 PoE operation at the PSE and ~51 W delivered to the PD load after cable loss. The device also features foldback protection that activates when RTN voltage exceeds 14.5 V.

How does the TPS2373-3RGWR implement automatic Maintain Power Signature (MPS)?

The TPS2373-3RGWR implements automatic MPS by monitoring RTN current and generating programmable pulsed current via the AMPS_CTL pin. When RTN current falls below 18–38 mA (configurable via external resistor), the IC automatically initiates MPS pulses with duty cycles selectable via MPS_DUTY (5.4%, 8.1%, or 12.5%). This eliminates manual timing component selection and ensures compatibility with Type 1–4 PSEs without firmware intervention.

What is the purpose of the VC_OUT pin on the TPS2373-3RGWR?

The VC_OUT pin on the TPS2373-3RGWR provides a regulated 13.5–15 V bias supply for external PWM controllers, eliminating the need for an auxiliary transformer winding or separate bias IC. It sources up to 60 mA and features UVLO with adjustable thresholds (6.9 V rising, 3.9 V falling when UVLO_SEL grounded). This advanced startup function simplifies DC-DC converter design and reduces required bulk capacitance.

Can the TPS2373-3RGWR operate with both PoE and an external AC adapter?

Yes, the TPS2373-3RGWR supports dual-power operation via its APD (Auxiliary Power Detect) pin. When APD is raised >1.65 V above RTN, the IC disables the internal PoE pass MOSFET, forces TPH low, and deactivates TPL/BT - allowing seamless priority to an external adapter. This enables failover-capable systems like industrial gateways and enterprise phones without external OR-ing circuitry.

What thermal considerations apply to the TPS2373-3RGWR in a 5.0 mm × 5.0 mm VQFN package?

The TPS2373-3RGWR in RGW (VQFN-20) package has a junction-to-board thermal resistance (RθJB) of 17.9°C/W and requires the exposed thermal pad to be soldered to a solid VSS copper pour. At 1.85 A continuous current and 0.3 Ω rDS(on), power dissipation reaches ~1.03 W - necessitating ≥4 cm² of 2-oz copper for operation at 125°C ambient. Thermal shutdown activates at 158°C with 20°C hysteresis to prevent damage.