SI3471A-A01-IMR - 90W 802.3bt PoE PSE Controller | Skyworks
N.º de pieza: SI3471A-A01-IMR ✓ Activo| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $5.89 | $5,89 |
| 10 | $5.55 | $55,50 |
| 100 | $5.05 | $505,00 |
| 500 | $4.65 | $2.325,00 |
| 1.000 | $4.3 | $4.300,00 |
SI3471A-A01-IMR Descripción general
A PoE PSE controller is the power-management device that lives on the switch or injector side of a PoE link. It is responsible for safely discovering whether a Powered Device (PD) is connected at the far end of the Ethernet cable, classifying its power requirement, and only then closing the internal or external MOSFET path to deliver power. The PSE controller hierarchy sits under power management ICs, and the Si3471 sits in its top tier because it implements the 802.3bt Type 4 / Class 8 specification, which raises per-port power to 90W using all four twisted pairs.
Key features of the Si3471 include full IEEE 802.3bt compliance for detection, connection check, classification, and power-on sequencing, single-signature and dual-signature PD support, and operation across an industrial -40C to +85C temperature range. The controller supervises the pass MOSFETs and manages inrush current limiting, overcurrent protection, and fault reporting, all functions mandated by the IEEE standard and required for interoperability with certified PDs.
Technically, the Si3471 follows the IEEE 802.3bt state machine for detection (two-point DC discovery), connection check, classification (including Layer 2 LLDP-based power negotiation handled at system level), and controlled power-on. The datasheet illustrates operation waveforms for both single-signature and dual-signature PD topologies, which determine whether power is delivered on two or four pairs and how the PD presents its detection signature.
Typical applications include enterprise Ethernet switches, PoE midspan injectors, security camera and wireless access point infrastructure, and industrial networking equipment that must power 4-pair Class 8 loads such as PTZ cameras, video phones, and thin clients.
A key design consideration is thermal management of the external pass MOSFETs at 90W: at a 54V PSE rail and typical PoE cable resistance, the controller itself dissipates little power, but Rds(on) of the external FETs directly drives port efficiency and connector temperature rise.
This page synthesizes distributor pricing, verified specifications, ordering-option differences, and practical design notes not found in the manufacturer datasheet alone.
Alternativas directas para SI3471A-A01-IMR — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
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SI3471A-A01-IM
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SI3471A-B01-IMR
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SI3471A-A01-IMR Valores máximos y características eléctricas
| Función | PoE PSE Controller |
| Number of PoE Ports / Channels | 1 |
| PoE Standards Supported | IEEE 802.3af, 802.3at, 802.3bt |
| Max Power per Port | 90 W (802.3bt Type 4) |
| PSE Type | Power Sourcing Equipment (PSE) |
| PD Signature Support | Single-signature and dual-signature |
| Tensión de alimentación | 3 V to 3.6 V |
| Temperatura de funcionamiento | -40C to +85C |
| Encapsulado | 38-QFN (5x7 mm) |
| Tipo de montaje | Surface Mount |
| Functions Performed | Detection, connection check, classification, power on |
| Standard Packaging | Tape & Reel (R suffix), 2500 units |
| Estado RoHS | Compliant |
| Marca | Skyworks Solutions Inc. (formerly Silicon Labs) |
| Categoría | Power Over Ethernet (PoE) Controllers |
Guía de configuración de pines de SI3471A-A01-IMR 38-qfn (5x7 mm)
Configuración de pines para SI3471A-A01-IMR (encapsulado 38-qfn (5x7 mm)). Este dispositivo de potencia presenta terminales de puerta, drenador y fuente. Para encapsulados no polarizados, consulte la hoja de datos del fabricante para conocer la orientación exacta del pin 1 y los detalles del footprint. Las aplicaciones habituales incluyen el diseño de fuentes de alimentación, el accionamiento de motores y la conmutación de cargas.
No hay datos detallados de patillaje disponibles para SI3471A-A01-IMR.
Consulte la hoja de datos para ver la configuración completa de patillas.
Aplicaciones típicas
SI3471A-A01-IMR es adecuado para 6 aplicacións: IEEE 802.3bt Ethernet Switch Ports, PoE Midspan Injectors, IP Security Camera Infrastructure, Wireless Access Point Backhaul Power, Industrial Network Switches, Building Automation and Smart Lighting over PoE.
IEEE 802.3bt Ethernet Switch Ports
The SI3471A-A01-IMR fits single-port or per-port supervisory PoE circuitry in enterprise and industrial switches that must deliver up to 90W per port under IEEE 802.3bt Type 4. Its compliance with 802.3af/at/bt detection, connection check, classification, and power-on lets one port design service legacy 15.4W IP phones and modern 90W Class 8 loads interchangeably. The controller manages external pass MOSFETs and inrush limiting per the IEEE standard, keeping the switch port interoperable with any certified PD. In a 4-pair design, engineers pair the Si3471 with PoE-rated magnetics and diode bridges; the 3V to 3.6V supply range matches common switch-system 3.3V rails, removing an auxiliary regulator from the BOM.
Recomendado
PoE Midspan Injectors
Midspan injectors add PoE power to existing Ethernet runs without replacing the switch, and the SI3471A-A01-IMR is purpose-built for this single-port role. Because the injector delivers power on exactly one port, a single-channel controller keeps cost and board area minimal while still supporting the full 90W 802.3bt budget for high-power cameras and radios. The Si3471 datasheet documents the complete detection, connection-check, classification, and power-on waveform sequence for single-signature and dual-signature PDs, which is precisely the interop surface a midspan must get right. Its -40C to +85C rating suits injector housings mounted outdoors or in ceiling spaces where ambient temperatures rise above office conditions.
Recomendado
IP Security Camera Infrastructure
PTZ cameras with heaters, wipers, and IR illuminators routinely draw 60W to 90W, which only IEEE 802.3bt Type 4 PSEs can deliver over four pairs. The SI3471A-A01-IMR provides that 90W capability with standards-compliant classification so the camera can negotiate its true power class. In a recorder or NVR-side injector, the controller protects the cable plant: inrush limiting and overcurrent supervision per 802.3bt prevent damage from shorted or mis-wired camera drops. The industrial -40C to +85C operating range aligns with surveillance enclosures in unconditioned outdoor sites, and the compact 5x7 mm QFN-38 keeps the power section small enough for dense multi-camera injector blades.
Recomendado
Wireless Access Point Backhaul Power
Wi-Fi 6 and Wi-Fi 7 enterprise access points with multi-radio aggregation commonly need more than the 30W of 802.3at, making 802.3bt PSE capability in the aggregation switch or injector mandatory. The SI3471A-A01-IMR supplies up to 90W with full Type 4 classification, letting an AP draw the power its radios require while remaining backward-compatible when cabled to a smaller PD. Placed in a wall-plate or ceiling-injector product, the controller's 3V to 3.6V digital supply integrates directly with the system 3.3V rail. Engineers should size the external pass MOSFETs for the full 90W since the controller supervises rather than integrates the power path, keeping thermal losses in components chosen for the budget.
Recomendado
Industrial Network Switches
Factory-floor switches must power IP intercoms, barcode readers, and edge PLCs over long cable runs while surviving harsh temperatures, and the SI3471A-A01-IMR addresses both needs with its -40C to +85C rating and full 802.3af/at/bt protocol support. In DIN-rail or panel-mounted industrial switches, the controller's standards-mandated detection prevents applying 54V to non-PoE devices sharing the same cable infrastructure, a frequent failure mode in mixed industrial networks. The 90W per-port budget covers the heaviest industrial PDs, while backward compatibility protects legacy 802.3af sensors. Its RoHS-compliant QFN-38 assembly is compatible with standard industrial SMT processes, and the IM tray option suits low-volume contract manufacturing common in industrial equipment.
Recomendado
Building Automation and Smart Lighting over PoE
PoE-based building systems - LED luminaires, occupancy sensors, door controllers, and HVAC actuators - are powered from the same structured cabling as data, and the SI3471A-A01-IMR gives a PoE lighting manager or aggregator standards-compliant 90W ports for high-output fixtures. Correct 802.3bt classification ensures each luminaire negotiates its actual draw, allowing the system controller to budget total power across many ports without oversubscription trips. The controller's detection and connection-check stages protect non-PoE devices on shared cabling. With a 3V to 3.6V supply drawn from the manager's 3.3V rail and a small 5x7 mm QFN footprint, the port electronics fit dense multi-channel power distribution boards typical of PoE lighting racks.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para SI3471A-A01-IMR — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | SI3471A-A01-IM | SI3471A-B01-IMR |
|---|---|---|---|
| Package | 38-QFN (5x7 mm) | 38-QFN (5x7 mm) - same | 38-QFN (5x7 mm) - same |
| Brand | Skyworks Solutions | Skyworks Solutions | Skyworks Solutions |
| PoE Standards | 802.3af, 802.3at, 802.3bt | 802.3af, 802.3at, 802.3bt | 802.3af, 802.3at, 802.3bt |
| Max Port Power | 90 W | 90 W | 90 W |
| Channels | 1 | 1 | 1 |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C |
| Packaging | Tape & Reel (2500 units) | Tray | Tape & Reel |
| Drop-in Compatibility | Reference | Pin-to-pin, 100% | Pin-to-pin, 90% (default configuration option differs) |
Diferenciadores clave
- Full IEEE 802.3bt Type 4 support at 90W (frente a SI3471A-A01-IM)
- Single-channel simplicity for injector designs (frente a Multi-port PSE controllers (e.g., TI TPS2388, 8 channels))
- Dual-signature and single-signature PD support (frente a Legacy 802.3at-only PSE controllers)
Notas de diseño
Estimated: at a 90W 802.3bt load on a 54V PSE rail, port current is roughly 1.7A, so the external pass MOSFETs dominate losses - a FET pair with 20 mOhm total Rds(on) dissipates about 2 x 1.7A^2 x 10 mOhm = 58 mW, while a 60 mOhm part would dissipate over 170 mW per FET. Select low-Rds(on), avalanche-rated MOSFETs and give them 1 oz or better copper pours; the Si3471 itself supervises rather than passes the main power, so its QFN-38 needs only normal PCB cooling.
The Si3471 implements the IEEE 802.3bt state machine (detection, connection check, classification, power on) for both single-signature and dual-signature PDs - verify which PD signature type your load presents, because 4-pair dual-signature PDs require the full Type 4 front end (four diode bridges and both pair-set MOSFET switches). Also confirm the ordering suffix: IMR is tape and reel for automated assembly; IM is tray. Mixing suffixes on an SMT line will cause feeder errors.
Supply the controller from the system 3.3V rail, which sits inside its specified 3V to 3.6V operating window. Decouple VDD with a 0.1 uF ceramic placed within 2 mm of the pin, and keep the detection/classification sense resistor paths (per the Si3471 datasheet typical application) as short, Kelvin-routed traces so 802.3bt classification accuracy is not degraded by PCB IR drop on shared ground returns.
Información de cumplimiento
RoHS compliant per JLCPCB and LCSC product listings. REACH, halogen-free, lead-free and conflict-minerals declarations were not present in the verified distributor data; consult official Skyworks compliance documentation.
