KS8995XA Integrated 5-Port 10/100 QoS Switch Rev 2.6 General Description The KS8995XA is a highly integrated Layer-2 quality of service (QoS) switch with optimized bill of materials (BOM) cost for low port count, cost-sensitive 10/100Mbps switch systems. It also provides an extensive feature set including three different QoS priority schemes, a dual MII interface for BOM cost reduction, rate limiting to offload CPU tasks, software and hardware power-down, a MDC/MDIO control interface and port mirroring/monitoring to effectively address both current and emerging Fast Ethernet applications. The KS8995XA contains five 10/100 transceivers with patented mixed-signal low-power technology, five media access control (MAC) units, a high-speed non-blocking switch fabric, a dedicated address lookup engine, and an on-chip frame buffer memory. All PHY units support 10BASE-T and 100BASE-TX. In addition, two of the PHY units support 100BaseFX (Ports 4 and 5). Functional Diagram 10/100 T/Tx 1 10/100 MAC 1 Auto MDI/MDI-X 10/100 T/Tx 2 10/100 MAC 2 Auto MDI/MDI-X 10/100 T/Tx 3 10/100 MAC 3 Auto MDI/MDI-X 10/100 T/Tx/Fx 4 10/100 MAC 4 Auto MDI/MDI-X MII-P5 MDC, MDI/O MII-SW or SNI 10/100 T/Tx/Fx 5 10/100 MAC 5 LED0[5:1] LED1[5:1] LED2[5:1] SNI LED I/F Control Registers 1K Look-Up Engine FIFO, Flow Control, VLAN Tagging, Priority Auto MDI/MDI-X Queue Mgmnt Buffer Mgmnt Frame Buffers EEPROM I/F KS8995XA Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com September 2008 M9999-091508