TPS2371PW - PoE PD Power Interface Switch, IEEE 802.3af | TI
N.º de pieza: TPS2371PW ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $2.45 | $2,45 |
| 10 | $2.18 | $21,80 |
| 100 | $1.92 | $192,00 |
| 500 | $1.65 | $825,00 |
| 1.000 | $1.38 | $1.380,00 |
| 3.000 | $1.12 | $3.360,00 |
TPS2371PW Descripción general
A PoE PD interface controller is a specialized power management IC that handles the negotiation and power-path startup between a Power Sourcing Equipment (PSE) and a powered load. The TPS2371 sits between the Ethernet RJ-45 magnetics and the DC-DC converter that follows it, performing signature detection (25 kΩ resistor presentation), classification (one of Class 0-4 current signatures), and inrush-limited turn-on of the bulk input capacitor. This functional block sits within the broader power management IC hierarchy, which includes voltage regulators, supervisors, and DC-DC converters.
Key features include 100 V absolute maximum input voltage on the VDD pin, programmable inrush current limiting via an external resistor, automatic classification current shutoff above 20 V to reduce internal dissipation, and support for both current- and voltage-mode classification schemes. The internal N-channel FET has a typical on-resistance of 1 Ω and supports continuous currents up to 0.5 A at the return side, with transient capability to 1.5 A.
The TPS2371 is designed to operate from a single twisted-pair or 4-pair Ethernet input. The low-side (return-side) topology allows the upstream DC-DC converter to use a non-isolated buck or a flyback configuration tied to chassis ground. Internal protection includes thermal shutdown, input undervoltage lockout, and a 100 V surge-tolerant drain connection.
Typical applications include 802.3af-compliant PoE PD endpoints such as wireless access points, VoIP phones, IP cameras, IoT sensors, and low-power industrial Ethernet nodes. Designers benefit from a reduced BOM by eliminating external pass-MOSFETs and discrete signature resistors, while the TSSOP-8 package supports automated assembly.
When designing with this part, ensure the upstream Ethernet physical layer (PHY) magnetics provide the proper center-tap injection point to the VDD pin, and verify that the downstream DC-DC startup current draw does not exceed the configured inrush limit. The 8-pin TSSOP (PW) is a thermally enhanced package but still requires adequate copper pour for sustained high-current operation.
Alternativas directas para TPS2371PW — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Variantes de esta serie
Modelos de la misma serie compatibles directamente con TPS2371PW (mismo factor de forma y huella) — difiere en Package, Product Type, Inrush Current Control, Operating Temperature Range.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
TPS2371PW
✅ Sustitución directa✓ En stock
$1.12 / unidad
Ver hoja de datos →TPS2371PWR
✅ Sustitución directa✓ En stock
Consulte el precio
Ver hoja de datos →TPS2371PWG4
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
TPS2371PWRG4
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
TPS23754PWPR
✅ Sustitución directa📋 Alternativa de referencia (no en el catálogo)
TPS2371PW Valores máximos y características eléctricas
| Product Type | PoE PD Power Interface Switch |
| Standard | IEEE 802.3af (legacy compatible) |
| Input Voltage (VDD) | 0 V to 100 V (absolute max) |
| Continuous FET Current | 0.5 A |
| Peak FET Current | 1.5 A |
| Internal FET Rds(on) | 1 Ω (typical) |
| Inrush Current Control | Externally programmable |
| Classification Support | Class 0-4 (current and voltage mode) |
| Classification Disable Voltage | Above 20 V (automatic) |
| Detection Signature | 25 kΩ presentation |
| FET Topology | Low-side (return-side) N-channel |
| Rango de temperatura de funcionamiento | -40 °C to +85 °C |
| Encapsulado | 8-pin TSSOP (PW) |
| Tipo de montaje | Surface Mount |
| Nivel MSL | 2 (per JEDEC J-STD-020, lifetime floor-life 1 year) |
| Estado RoHS | Compliant (per TI product page) |
| Apagado térmico | Yes (internal) |
| Undervoltage Lockout | Yes (internal) |
Configuración de pines de TPS2371PW
| Pin 1 | RTN — Return (drain of internal low-side pass FET) |
| Pin 2 | GND — Analog ground / reference |
| Pin 3 | VDD — Positive input supply (PoE 48 V nominal, 100 V abs max) |
| Pin 4 | CLASS — Classification programming pin (sets Class 0-4 current) |
| Pin 5 | DET — Detection signature pin (25 kΩ presentation) |
| Pin 6 | UVLO — Undervoltage lockout threshold set pin |
| Pin 7 | ISNS — Inrush / current sense programming pin |
| Pin 8 | CT — Center-tap / spare control timing node |
Aplicaciones típicas
TPS2371PW es adecuado para 7 aplicacións: IEEE 802.3af VoIP Phone PD, Wireless Access Point PoE PD, IP Security Camera PoE Front-End, Industrial IoT Ethernet Sensor Node, PoE-Powered LED Lighting Driver Front-End, Smart Building HVAC / Access Controller, PoE-Powered Single-Board Computer (SBC) PD.
IEEE 802.3af VoIP Phone PD
The TPS2371PW is purpose-built for IEEE 802.3af-powered VoIP phones where 6-13 W is delivered through the Ethernet cable. It presents the 25 kΩ detection signature and one of five classification currents (Class 0-4) to negotiate power with the PoE PSE, then operates the integrated 1 Ω low-side FET to inrush-limit the local bulk capacitor at startup. The TSSOP-8 footprint and 100 V VDD tolerance (per TI datasheet) give the VoIP phone PCB a tight, robust front end that survives cable-discharge transients. After the TPS2371PW gates the return side, an isolated flyback converter (e.g., TI UCC28C43) down-converts 48 V to 3.3 V/5 V rails for the SoC and audio codec. Engineers should pick the inrush-sense resistor so the 5-frame inrush limit of 802.3af is honored under the phone's worst-case bulk-cap charge.
Recomendado
Wireless Access Point PoE PD
In Wi-Fi access points fed by PoE, the TPS2371PW acts as the 802.3af PD interface that turns the Ethernet cable into a clean, sequenced power rail. The internal 0.5 A / 1.5 A low-side pass FET (1 Ω Rds(on)) allows the AP to draw up to 13 W under 802.3af while keeping the inrush below the spec-mandated limit and adding <100 mW of dissipation across the pass element at full load. The 100 V absolute-max VDD gives safety margin against inductive kick from the RJ-45 magnetics, and the TPS2371PW's automatic classification-current disable above ~20 V reduces PD-side heating during normal operation. The 8-pin TSSOP (PW) keeps the BOM within the AP RF-shielded front end.
Recomendado
IP Security Camera PoE Front-End
Outdoor IP cameras are a canonical 802.3af use case for the TPS2371PW because they share a single outdoor-rated Ethernet cable for both data and power. The TPS2371PW handles the detection handshake and inrush control with its integrated 1 Ω pass FET, then a downstream buck or flyback produces 12 V for the IR illuminator, 5 V for the image sensor, and 3.3 V/1.2 V for the ISP. With -40 °C to +85 °C operation and 100 V VDD transient tolerance, the TPS2371PW survives outdoor cabling-induced surges that frequently exceed 57 V nominal. Its TSSOP-8 (PW) footprint is small enough to fit inside the camera's watertight housing and is rated MSL-2 for standard reflow.
Recomendado
Industrial IoT Ethernet Sensor Node
In factory-floor Ethernet sensor nodes, the TPS2371PW provides the 802.3af-compliant PD interface to harvest power from the plant's PoE switch while tolerating the elevated -40 °C to +85 °C ambient. The integrated low-side FET keeps the BOM small (no external pass MOSFET) and the 100 V VDD transient rating provides robust behavior against industrial grid- and motor-induced surges on cable runs. Once the TPS2371PW closes the return path, a non-isolated buck (e.g., TPS54331) steps 48 V to 24 V/12 V for sensor excitation and 3.3 V for the MCU/wireless transceiver. The 8-pin TSSOP footprint is compatible with surface-mount assembly lines used by industrial OEM module makers.
Recomendado
PoE-Powered LED Lighting Driver Front-End
Low-power PoE LED fixtures (under 12.95 W / Class 3) use the TPS2371PW at their input to negotiate power and inrush-limit the bulk capacitor before a downstream constant-current LED driver takes over. The integrated 1 Ω Rds(on) pass FET drops up to 0.5 V at full load, well within headroom, and the 100 V VDD rating covers any reflector-induced ringing on long cable runs. The TSSOP-8 (PW) package keeps the driver board compact enough to fit inside the fixture junction box. Designers pair the TPS2371PW with a downstream buck controller (TPS54331) and a low-side current-sense LED driver to deliver flicker-free, dimmable PoE-powered lighting.
Recomendado
Smart Building HVAC / Access Controller
Building automation controllers (door access panels, smart thermostats, BACnet nodes) frequently draw 5-10 W from PoE, well within 802.3af Class 2-3. The TPS2371PW performs the signature and class handshake, then switches its return-side FET to power an offline flyback or non-isolated buck serving the MCU, RS-485 transceiver, and display. Its small 8-pin TSSOP (PW) outline allows the entire front-end to fit on the connector's egress side, while the 100 V VDD tolerance handles residual charge from capacitive ESCC protection circuits. The -40 °C to +85 °C operating temperature range covers both indoor plenum and outdoor receptacle junction environments.
Recomendado
PoE-Powered Single-Board Computer (SBC) PD
Single-board computer designs (industrial gateways, digital signage players) that take PoE input use the TPS2371PW as the 802.3af PD interface, delivering up to 12.95 W (Class 3) directly from the Ethernet cable to the downstream DC-DC converters powering the SoC, memory, and peripherals. The TPS2371PW's automatic classification-current disable above ~20 V keeps internal dissipation low during steady-state operation, while its integrated low-side FET eliminates the external power-MOSFET that would otherwise have to be added to the SBC's input stage. The TSSOP-8 (PW) is compatible with standard 4-layer SBC reflow profiles and is MSL-2 rated for one-year floor life.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para TPS2371PW — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | TPS2371PWR | TPS2371PWG4 | TPS2371PWRG4 | TPS23754PWPR |
|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | TSSOP-8 (PW) | TSSOP-8 (PW) | TSSOP-8 (PW) | TSSOP-8 (PW) | TSSOP-14 (PWP) - larger outline |
| Product Family | TPS2371 (PD interface + pass FET) | TPS2371 (tape-and-reel) | TPS2371 (G4 lead-free finish) | TPS2371 (G4, tape-and-reel) | TPS23754 (PD interface + PWM controller) |
| IEEE PoE Standard | 802.3af (legacy) | 802.3af (legacy) | 802.3af (legacy) | 802.3af (legacy) | 802.3at-compatible |
| Max Input Voltage (VDD abs) | 100 V | 100 V | 100 V | 100 V | 100 V |
| Integrated Pass FET Rds(on) | 1 Ω (typical) | 1 Ω | 1 Ω | 1 Ω | 0.5 Ω (improved in TPS23754) |
| Continuous FET Current | 0.5 A | 0.5 A | 0.5 A | 0.5 A | 0.84 A |
| Operating Temperature | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +125 °C (extended) |
| PWM / DC-DC Controller Integrated | No | No | No | No | Yes (primary-side regulation controller) |
Diferenciadores clave
- Integrated low-side pass FET in a TSSOP-8 (frente a TPS23754PWPR (TSSOP-14))
- Auto-disable of classification current above 20 V (frente a Discrete 802.3af implementations)
- 100 V absolute-maximum VDD rating (frente a Lower-rated discrete PD front ends)
- Compatible with both current- and voltage-mode classification (frente a TPS23753APWR)
Notas de diseño
Do not tie the TPS2371PW's CLASS pin directly to GND without accounting for the required class programming resistor. The device presents a class-current signature according to the resistor on CLASS at the moment the PSE applies classification voltage. A missing or wrong value will register the PD as Class 0 (default 13 W request), potentially tripping an over-current in the PSE. Always populate the CLASS resistor with the value matching the documented Class 0-4 current in IEEE 802.3af §25 / §33.
At full 802.3af load (0.5 A continuous through the internal low-side FET), the 8-pin TSSOP (PW) dissipates approximately 0.25 W across the 1 Ω Rds(on). Combined with internal bias power, total dissipation reaches 0.3-0.4 W; in a sealed IP66 enclosure this may push the junction above the operating limit. Provide at least 1 square inch of copper pour on the TSSOP center pad/GND pin or move to a higher-grade PoE PD controller family (TPS23754) for sustained high-load deployments.
Place the TPS2371PW's VDD bypass capacitor (1 nF / 0.1 µF ceramic) within 5 mm of the VDD pin to suppress the high-frequency noise from PSE chopping transients. Keep high-voltage VDD traces at least 6 mm from low-voltage CLASS and DET traces to prevent capacitive coupling that can disturb detection signatures during the 25 kΩ presentation phase. The low-side return trace (RTN pin to system GND) should be wide (>=0.5 mm per amp) to minimize its contribution to total dissipation.
Estimate: Rout a star ground topology with the TPS2371PW's GND pin as the single point of return for CLASS and DET reference currents. The TVS protection (e.g., SMAJ58A) must be placed at the RJ-45 connector before the TPS2371PW, not after. A common layout error is routing the PSE-side center-tap return through the TPS2371PW's GND pin, which inadvertently grounds the detection signature offset; tie the magnetics center-tap return to VDD (positive-side topology), since the TPS2371PW is a low-side return device.
Información de cumplimiento
RoHS compliance per TI product page (TPS2371PW). REACH status not explicitly listed on TI product page; marked 'unknown' pending verification. AEC-Q100 automotive qualification is 'not_applicable' - TPS2371 family is industrial/consumer grade; for AEC-Q100 PoE needs consult TI directly.
