KS8999I

Specialized ICS Overview

The KS8999I is a 9-port (8+1) 10/100 integrated Ethernet switch manufactured by Microchip Technology. It incorporates eight physical layer transceivers and one MII/SNI interface within a single package. The device features an internal frame buffer with 128K bytes of SRAM, providing high-performance memory bandwidth for wire-speed reception and transmission. It supports IEEE 802.3x flow control, VLAN tagging, and automatic address learning. The component operates in surface-mount 208-PQFP packages and is designed for industrial temperature ranges.

Specialized ICS Feature Summary

• Integrated 9-port architecture with eight 10/100 PHYs and one MII/SNI port
• 128K Byte on-chip SRAM frame buffer supporting 2.0Gbps memory bandwidth
• Supports 802.1p priority, port-based VLAN, and DiffServ
• Hardware-based auto-negotiation, MDI/MDI-X crossover, and flow control

Specialized ICS Applications

• Industrial network interface modules
• Port switching systems requiring integrated PHYs
• Router applications utilizing external MAC interfaces

Specialized ICS Procurement Notes

Verify the specific manufacturing source, as the part was originally developed by Micrel before acquisition by Microchip. Confirm the exact package variant (208-PQFP) and ensure compatibility with required voltage levels (2.1V and 3.3V). Check for end-of-life status or alternative sourcing options if current production availability is limited.

Specialized ICS Selection Notes

Select this component when a design requires multiple integrated 10/100 ports without external PHYs. Ensure the PCB layout accommodates the 208-pin PQFP footprint. Verify that the system power supply can provide the necessary dual voltage rails (2.1V for core logic and 3.3V for I/O) and meets the maximum current consumption requirements.

Specialized ICS Part Context

The KS8999I belongs to the KS8999 family of integrated switches. It combines the functionality of a Layer 2 switch engine with physical layer transceivers, reducing bill-of-materials count compared to discrete solutions. The 'I' suffix typically denotes industrial temperature rating specifications.

Specialized ICS Replacement Considerations

Direct replacements may include other members of the KSZ8999 series, such as the KSZ8999M, though pinouts and feature sets should be verified against datasheets.