KSZ8851SNLI - 10/100 Ethernet SPI Controller | Microchip
N.º de pieza: KSZ8851SNLI ✓ ActivoKSZ8851SNLI Descripción general
A Fast Ethernet controller is a network-interface semiconductor that combines physical-layer signaling and higher-level frame processing. Within the product hierarchy, the KSZ8851SNLI is an Ethernet controller interface IC with an integrated Ethernet PHY and MAC. Its SPI host interface provides a practical way to add wired network connectivity to embedded systems without requiring a parallel host bus or a dedicated Ethernet processor.
Key device features include a single Ethernet port, integrated 10/100BASE-T/TX PHY, integrated MAC, and an SPI interface. The manufacturer documentation identifies 3.3 V as the main supply and provides 1.8 V, 2.5 V, and 3.3 V options for VDD I/O, allowing the digital interface voltage to be matched more closely to the host microcontroller. The SNLI designation identifies the industrial-temperature-grade version of the KSZ8851SNL family.
The KSZ8851SNL family supports SPI, 8-bit, 16-bit, and 32-bit non-PCI CPU interfaces, with package options of 32, 48, and 128 pins. The 32-QFN KSZ8851SNLI is therefore the SPI-oriented option for compact embedded equipment. Integrating the PHY and MAC reduces the number of external Ethernet interface functions required, while the SPI connection limits host-side wiring and allows a microcontroller to manage registers and network traffic through a serial interface.
Typical uses include industrial monitoring, networked sensors, building controls, embedded access equipment, and compact gateway products. For these systems, the device can provide a single 10/100 copper port while the host handles application traffic, configuration, and network management. A board design must still provide the required magnetic interface, termination, reference circuitry, clocking, supply rails, and controlled-layout implementation described by the manufacturer hardware checklist.
Designers should evaluate the SPI clock and signal-integrity requirements, power-supply sequencing, and Ethernet magnetics together rather than treating the controller as a stand-alone Ethernet jack interface. The 3.3 V supply and selectable 1.8 V, 2.5 V, or 3.3 V VDD I/O levels are important for host compatibility, while the compact 5x5 mm QFN footprint requires a land pattern and thermal strategy appropriate for a leadless package.
This page combines the manufacturer identification, SPI and 10/100 Ethernet capabilities, verified-source links, and practical engineering guidance. It also distinguishes the directly documented same-family option from cross-package Ethernet devices, helping engineers make a footprint-aware choice without treating every Ethernet PHY as a drop-in replacement.
Alternativas directas para KSZ8851SNLI — 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 KSZ8851SNLI (mismo factor de forma y huella) — difiere en Ethernet Speed, Host Interface, Package.
KSZ8851SNL
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Ver hoja de datos →KSZ8851SNLI Especificaciones
| Ethernet Speed | 10/100 Mbps |
| Ethernet Port Count | 1 port |
| Integrated PHY | 10/100BASE-T/TX PHY |
| Integrated MAC | Yes |
| Host Interface | SPI |
| Main Supply Voltage | 3.3 V |
| VDD I/O Voltage Options | 1.8 V, 2.5 V, or 3.3 V |
| Temperature Grade | Industrial grade |
| Encapsulado | 32-QFN (5x5 mm) |
| Tipo de montaje | Surface mount |
| Lead-Free Package | Lead-free |
| KSZ8851 Family Package Options | 32, 48, and 128 pins |
| KSZ8851 Family CPU Interface Options | SPI, 8-bit, 16-bit, and 32-bit non-PCI |
| Media Type | Copper Ethernet |
Guía de configuración de pines de KSZ8851SNLI 32, 48, and 128 pins
Configuración de pines para KSZ8851SNLI (encapsulado 32, 48, and 128 pins). La numeración de pines, las funciones y los diagramas de conexión se definen en la hoja de datos del fabricante. Consúltela para conocer el footprint exacto y las directrices de soldadura.
No hay datos detallados de patillaje disponibles para KSZ8851SNLI.
Consulte la hoja de datos para ver la configuración completa de patillas.
Aplicaciones típicas
KSZ8851SNLI es adecuado para 6 aplicacións: Industrial Monitoring Terminal, Networked IoT Sensor Gateway, Building Automation Controller, Embedded Access Equipment, Compact Networked Appliance, Embedded Test and Measurement Device.
Industrial Monitoring Terminal
The KSZ8851SNLI suits an industrial monitoring terminal that must report sensor or machine data over a 10 Mbps or 100 Mbps copper Ethernet link. Its integrated 10/100BASE-T/TX PHY and MAC reduce the number of separate network functions connected to the host microcontroller, while the SPI interface limits the required host-side signals. The 3.3 V main supply and selectable 1.8 V, 2.5 V, or 3.3 V VDD I/O levels help the controller align with different microcontroller interface voltages. The industrial-temperature-grade SNLI designation is particularly relevant where ambient conditions exceed ordinary commercial expectations. The board still needs manufacturer-recommended magnetic-interface and termination circuitry, with the Ethernet section and SPI route laid out to minimize data-integrity risks.
Recomendado
Networked IoT Sensor Gateway
A compact IoT gateway can use the KSZ8851SNLI to add one wired Fast Ethernet connection without requiring a parallel host interface. The device supports 10 Mbps and 100 Mbps operation, allowing the same controller to accommodate both lower-rate legacy links and higher-throughput traffic within a 10/100BASE-T network. SPI communication with the host helps conserve connector pins and board area, especially in a 32-QFN package measuring 5 mm by 5 mm. The separate choice of 1.8 V, 2.5 V, or 3.3 V VDD I/O can simplify host matching when the main device rail remains at 3.3 V. Designers should use the manufacturer hardware checklist to establish the required magnetics, termination, supply decoupling, and controlled PCB layout.
Recomendado
Building Automation Controller
The KSZ8851SNLI is appropriate for a building-automation controller that needs reliable wired connectivity to a central network. One integrated 10/100BASE-T/TX PHY and MAC provides the physical and data-link functions, while the SPI host interface supports connection to a microcontroller managing lighting, HVAC, access, or environmental-control logic. Supporting both 10 Mbps and 100 Mbps allows deployment across conventional Fast Ethernet infrastructure. Its industrial-temperature-grade status makes it a candidate for equipment placed outside conditioned cabinets, subject to confirmation of the exact environmental limits in the manufacturer datasheet. Practical implementation requires suitable network isolation or magnetics, termination components, clean 3.3 V supply rails, and careful separation of sensitive Ethernet and SPI routing.
Recomendado
Embedded Access Equipment
KSZ8851SNLI-based access equipment can connect an embedded host to a 10/100 copper network while retaining a compact serial host interface. The integrated MAC and PHY remove the need to implement those functions separately in the surrounding controller design, and SPI provides a practical management path for status, configuration, and frame transfer. The 32-QFN package occupies 5 mm by 5 mm, supporting compact designs where a larger 48-pin or 128-pin controller would be unnecessary. VDD I/O can be set to 1.8 V, 2.5 V, or 3.3 V to match the host interface, while the main supply is 3.3 V. The design must still implement the specified Ethernet magnetic coupling, clocking, reset behavior, and layout controls from the manufacturer documentation.
Recomendado
Compact Networked Appliance
The KSZ8851SNLI can serve as the wired-network interface in a compact appliance requiring one Fast Ethernet port and a microcontroller-based control plane. Its 10/100BASE-T/TX PHY and MAC support either 10 Mbps or 100 Mbps links, which is sufficient for configuration traffic, management data, and typical local-network traffic. The SPI host interface avoids a wide parallel bus and can simplify routing in a densely populated 5 mm by 5 mm QFN layout. Voltage flexibility for VDD I/O at 1.8 V, 2.5 V, or 3.3 V supports integration with different host logic levels, with the device main supply remaining at 3.3 V. Validation should include power sequencing, Ethernet return-path design, SPI timing, and the manufacturer checklist items before production release.
Recomendado
Embedded Test and Measurement Device
The KSZ8851SNLI can add Ethernet connectivity to a compact test or measurement instrument controlled by an SPI-capable processor. A single 10/100 copper port supports both 10 Mbps and 100 Mbps network rates, while the integrated MAC and PHY shorten the hardware path between the host and network medium. The 32-QFN package measuring 5 mm by 5 mm helps preserve instrument-panel space, and selectable 1.8 V, 2.5 V, or 3.3 V VDD I/O can ease host-voltage matching. The KSZ8851SNLI is the industrial-temperature-grade family member, making it relevant to laboratory and production equipment operating beyond standard commercial temperature conditions. The Ethernet magnetics, termination, reference components, and layout should follow the manufacturer hardware checklist exactly.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para KSZ8851SNLI — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | KSZ8851SNL |
|---|---|---|
| Brand | Microchip Technology | Microchip Technology |
| Package | 32-QFN (5x5 mm) | 32-QFN (5x5 mm) - same |
| Temperature Grade | Industrial grade | Standard-temperature version |
| Ethernet Speed | 10/100 Mbps | 10/100 Mbps |
| Ethernet Port Count | 1 port | 1 port |
| Integrated PHY | 10/100BASE-T/TX PHY | 10/100BASE-T/TX PHY |
| Integrated MAC | Yes | Yes |
| Host Interface | SPI | SPI |
| Main Supply Voltage | 3.3 V | 3.3 V |
| VDD I/O Voltage Options | 1.8 V, 2.5 V, or 3.3 V | 1.8 V, 2.5 V, or 3.3 V |
Diferenciadores clave
- Integrated MAC, PHY, and SPI host interface (frente a KSZ8851SNL)
- Compact 32-QFN integration (frente a KSZ8041RNL)
- Flexible host-side voltage selection (frente a KSZ8851SNL)
Notas de diseño
Use the manufacturer KSZ8851SNL Hardware Design Checklist before releasing the PCB. It covers the controller, one copper port, one uplink port, and SPI-interface implementation. Pay particular attention to the prescribed network magnetic interface, termination, reference components, clocking, reset, and supply arrangements rather than relying on a generic Ethernet layout copied from another PHY.
Plan the 3.3 V main supply and the selected 1.8 V, 2.5 V, or 3.3 V VDD I/O rail as separate implementation considerations. Keep the SPI interface voltage compatible with the host controller and review the power-up and reset sequence against the manufacturer datasheet. Place decoupling components at the appropriate device pins and preserve the documented return paths to reduce supply disturbance on the SPI and Ethernet circuits.
Route the SPI signals as a compact host-to-controller group with a continuous ground reference, and avoid introducing long stubs or unnecessary test-point branches. The Ethernet section should follow the manufacturer reference layout and magnetics guidance because trace geometry, return paths, and component placement affect network signal integrity. Validate both 10 Mbps and 100 Mbps operation during system testing rather than checking only link establishment.
Do not treat the KSZ8851SNLI as a generic Ethernet jack or assume that any 10/100 PHY is pin compatible. The component integrates both a PHY and MAC, uses a specific 32-QFN land pattern, and depends on the correct SPI host implementation. Verify the exact ordering code, temperature grade, pin assignments, firmware expectations, and package drawing before authorizing a substitution or production release.
Información de cumplimiento
The manufacturer evaluation-board page identifies the KSZ8851SNL as a 32-pin lead-free QFN device. No explicit RoHS, REACH, AEC-Q100, halogen-free, or conflict-minerals statement for KSZ8851SNLI appears in the cited records.
