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KSZ8851SNL

KSZ8851SNL

Microchip Technology (Micrel)
An SPI-attached 10/100 Ethernet controller from the KSZ family that serves as a direct alternative for designs requiring SPI host connectivity.
NRND5,261 in stock
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Overview

The KSZ8851SNL is a single-chip 10/100 Ethernet controller featuring an integrated MAC and PHY with a standard SPI host interface. It is designed to provide high-bandwidth connectivity for embedded systems that lack a dedicated media-independent interface (MII/RMII). The device includes an 18KB internal RAM buffer and supports low-power modes such as Energy Detect and Wake-on-LAN.

Why Choose This Part

It simplifies system design by using a 4-wire SPI interface for host communication, reducing pin count compared to parallel bus alternatives. The integrated 10/100 PHY includes HP Auto MDI-X for automatic cable crossover detection and LinkMD cable diagnostics to identify wiring faults.

Applications

Industrial Automation
Providing robust Ethernet connectivity to PLCs and industrial sensors using standard SPI headers on existing microcontrollers.
IoT Gateways
Adding networking capabilities to power-constrained edge devices that require a small 5x5mm QFN footprint.
Point-of-Sale Terminals
Secure wired communication for payment processing systems where EMI/EMC compliance and small form factors are required.
Embedded Linux SBCs
Adding a secondary Ethernet port to single-board computers that have available SPI buses but no additional RGMII lanes.

Key Specifications

Function Controller
Protocol Ethernet
Interface SPI
Standards 10/100 Base-T/TX PHY
Package / Case 32-VFQFN Exposed Pad
Voltage - Supply 1.8V, 2.5V, 3.3V
Operating Temperature 0degC ~ 70degC
Supplier Device Package 32-QFN (5x5)

Getting Started

Start development using the Microchip KSZ8851SNL evaluation board (ADM00609) which allows for direct connection to host MCU headers. Driver support is widely available in the Linux kernel and via Microchip MPLAB Harmony for 32-bit MCU integration.

KSZ8851 Family

Comparing specs that differ across variants. The current part is highlighted.

Part Number Temp Range Stock
KSZ8851SNL (this part) 0degC ~ 70degC 5,261
KSZ8851SNLI (Microchip (Micrel)) -40degC ~ 85degC 8,129

Also Consider

W5500 WIZnet - An SPI Ethernet controller that includes a hardwired TCP/IP stack to offload protocol processing from the host MCU.

Categories

Interface ICs > Ethernet PHY
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