Operating at 2.5 volts to meet low voltage and low power requirements, the KSZ8721 is a 10BaseT/100BaseTX/FX Physical Layer Transceiver, which provides an MII to transmit and receive data. It contains the 10BaseT Physical Medium Attachment (PMA), Physical Medium Dependent (PMD), and Physical Coding Sub-layer (PCS) functions. Moreover, the KSZ8721 has on-chip 10BaseT output filtering, which eliminates the need for external filters and allows a single set of line magnetics to be used to meet requirements for both 100BaseTX and 10BaseT. The KSZ8721 can automatically configure itself for 100 or 10 Mbps and full or half duplex operation, using on-chip Auto-Negotiation algorithm. It is an ideal choice of physical layer transceiver for 100BaseTX/10BaseT applications.Single chip 100BaseTX/100BaseFX/10BaseT physical layer solution 2.5V CMOS design, power consumption<200mW (excluding output driver current ) Fully compliant to IEEE 802.3u standard Supports Media Independent Interface (MII) and Reduced MII (RMII) Supports 10BaseT, 100BaseTX and 100BaseFX with Far_End_Fault Detection Supports power down mode and power saving mode Configurable through MII serial management ports or via external control pins Supports auto-negotiation and manual selection for 10/100Mbps speed and full/half-duplex mode On-chip built-in analog front end fi ltering for both 100BaseTX and 10BaseT LED outputs for link, activity, full/half duplex, collision and speed Supports back to back, FX to TX for media converter applications Supports MDI/MDI-X auto crossover 2.5V/3.3V tolerance on I/O Commercial temperature range: 0°C to +70°C Industrial temperature range: -40°C to +85°C Available in 48-pin SSOP and TQFP