Texas Instruments TPS2376PWRG4

Overview

TPS2376PWRG4 from Texas Instruments is an IEEE 802.3af-compliant Powered Device (PD) controller IC for Power over Ethernet applications, integrating a 0.58-Ω 100-V low-side MOSFET switch, programmable UVLO via dedicated UVLO pin, fixed 450-mA operational current limit, and adjustable inrush current control via ILIM pin. It operates across –40°C to 85°C and supports Class 3 PD implementations in VoIP phones and security cameras.

For engineers reviewing the TPS2376PWRG4 datasheet, TPS2376PWRG4 pinout, TPS2376PWRG4 application, or TPS2376PWRG4 equivalent, key selection considerations include its TSSOP-8 package, UVLO programmability (vs. fixed thresholds in TPS2375/TPS2377), 15-kV system-level ESD rating, and compatibility with legacy PoE infrastructure requiring adjustable turn-on voltage.

Technical Context

The TPS2376PWRG4 implements full IEEE 802.3af detection, classification, and power-up sequencing with dedicated UVLO pin enabling resistor-divider–based threshold programming (1.93 V lower / 2.49 V upper nominal). Its internal architecture includes a detection comparator with 0.3–3 µA offset current, classification current sourcing up to 41.2 mA at 255 Ω, and thermal shutdown at 135°C with 20°C hysteresis.

It features an open-drain PG output with 75–225 µs deglitch delay, RTN-sinking capability up to 515 mA, and inrush termination triggered when RTN current falls below 85% of steady-state inrush level. The ILIM pin accepts 62.5–500 kΩ resistors to set inrush current between 100–180 mA.

Key Specifications

Pinout & Package

TSSOP-8 (PW) package: 3.0 mm × 4.4 mm body, 0.65 mm pitch, exposed thermal pad (not electrically connected), RoHS-compliant, green molding compound.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Powered Device controller applications.

Compared with TPS2375PW and TPS2377PW, the TPS2376PWRG4 uniquely provides resistor-divider–based UVLO adjustment-enabling one hardware design to support both compliant and legacy PSEs without firmware or layout changes-while retaining identical inrush control, classification, and thermal protection behavior.

Availability

TPS2376PWRG4 is available at Aetrix Electronics and suitable for VoIP phones, WLAN access points, security cameras, and POS terminals requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for TPS2376PWRG4 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, delivering analog and embedded processing solutions for industrial, automotive, and communications markets.

The TPS237x family was designed specifically to simplify IEEE 802.3af PoE endpoint implementation, integrating detection, classification, UVLO, inrush control, and power switching into compact 8-pin packages for space-constrained networked devices.

FAQ

What is the primary function of the UVLO pin on the TPS2376PWRG4?

The UVLO pin on the TPS2376PWRG4 accepts an external resistor divider between VDD and VSS to set programmable upper and lower undervoltage lockout thresholds (nominal 2.49 V rising / 1.93 V falling). This enables custom turn-on voltage tuning for interoperability with legacy or noncompliant PoE sources, distinguishing it from the fixed-threshold TPS2375PWRG4 and TPS2377PWRG4. The TPS2376PWRG4 uses this pin exclusively - it is unconnected in other family members.

How does the TPS2376PWRG4 implement inrush current limiting?

The TPS2376PWRG4 implements adjustable inrush current limiting via the ILIM pin: connecting a resistor (62.5–500 kΩ) from ILIM to VSS sets the peak inrush current between 100–180 mA. This prevents input voltage sag during bulk capacitor charging and ensures compatibility with legacy PSEs requiring low inrush. The TPS2376PWRG4 terminates inrush when RTN current falls below 85% of the programmed level, then transitions to normal operation.

Can the TPS2376PWRG4 be used in Class 4 powered device applications?

Yes, the TPS2376PWRG4 supports Class 4 operation by configuring the CLASS pin with a 255-Ω ±1% resistor, which draws 38.0–41.2 mA during classification - within IEEE 802.3af Class 4 limits (36–44 mA). Its 0.58-Ω R_DS(on) and 515-mA RTN sinking capability handle the resulting 12.95-W maximum input power. The TPS2376PWRG4 maintains full compliance including MPS signature generation and thermal shutdown at 135°C.

What is the role of the PG pin on the TPS2376PWRG4, and how should it be interfaced?

The PG (Power-Good) pin on the TPS2376PWRG4 is an open-drain output that goes high-impedance when the internal MOSFET is enabled and inrush current limiting has completed. It must be pulled up externally (e.g., to 3.3 V or 5 V) to signal downstream DC/DC converters or microcontrollers. Its 75–225 µs deglitch delay prevents false triggering during transient events, and it references RTN - not VSS - ensuring accurate reporting relative to the switched load return rail.

Does the TPS2376PWRG4 require external components for IEEE 802.3af compliance?

Yes, the TPS2376PWRG4 requires three external passive components for full IEEE 802.3af compliance: a 24.9-kΩ ±1% resistor from DET to VDD for detection, a classification resistor (e.g., 255 Ω for Class 4) from CLASS to VSS, and an ILIM resistor (e.g., 178 kΩ) from ILIM to VSS for inrush control. The UVLO pin additionally requires a two-resistor divider. No external MOSFET, gate driver, or TVS diode is needed due to its integrated 100-V switch and 15-kV ESD rating.