KS8721B/BTKS8721B/BT 2.5V 10/100BasTX/FX MII Physical Layer Transceiver Rev. 2.3 General Description Features Operating at 2.5 volts to meet low voltage and low power Single chip 100BaseTX/100BaseFX/10BaseT physical requirements, the KS8721B/BT is a 10BaseT/100BaseTX/FX layer solution Physical Layer Transceiver, which provides an MII to transmit 2.5V CMOS design, power consumption <200mW (ex- and receive data. It contains the 10BaseT Physical Medium cluding output driver current ) Attachment (PMA), Physical Medium Dependent (PMD), and Fully compliant to IEEE 802.3u standard Physical Coding Sub-layer (PCS) functions. Moreover, the Supports Media Independent Interface (MII) and KS8721B/BT has on-chip 10BaseT output ltering, which Reduced MII (RMII) eliminates the need for external lters and allows a single Supports 10BaseT, 100BaseTX and 100BaseFX with set of line magnetics to be used to meet requirements for Far End Fault Detection both 100BaseTX and 10BaseT. Supports power down mode and power saving mode Con gurable through MII serial management ports or via The KS8721B/BT can automatically con gure itself for 100 external control pins or 10 Mbps and full or half duplex operation, using on-chip Supports auto-negotiation and manual selection for Auto-Negotiation algorithm. It is an ideal choice of physical 10/100Mbps speed and full/half-duplex mode layer transceiver for 100BaseTX/10BaseT applications. On-chip built-in analog front end ltering for both 100Ba- Data sheets and support documentation can be found on seTX and 10BaseT Micrels web site at www.micrel.com. Functional Diagram 4B/5B Encoder NRZ/NRZI Scrambler TXD3 MLT3 Encoder 10/100 TX+ Parallel/Serial TXD2 Transmitter Pulse TXD1 TX- Shaper TXD0 Parallel/Serial TXER Manchester Encoder TXC TXEN MII/RMII Adaptive EQ CRS Registers COL RX+ Base Line 4B/5B Decoder and Clock MDIO Wander Correction Descrambler Controller Recovery MDC RX- MLT3 Decoder Serial/Parallel Interface RXD3 NRZI/NRZ RXD2 RXD1 Auto RXD0 Negotiation RXER RXDV 10BaseT Manchester Decoder RXC Receiver Serial/Parallel Power LINK Down or Saving LED COL XI Driver FDX PLL XO SPD PWRDWN Micrel, Inc. 2180 Fortune Drive San Jose, CA 95131 USA tel + 1 (408) 944-0800 fax + 1 (408) 474-1000 KS8721B/BT Micrel, Inc. Features (continued) 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: 0C to +70C Industrial temperature range: 40C to +85C Available in 48-pin SSOP and TQFP Ordering Information Part Number Temperature Package Standard Pb-Free KS8721B KSZ8721B 0C to +70C 48-Pin SSOP KS8721BT KSZ8721BT 0C to +70C 48-Pin TQFP KSZ8721BI 40C to +85C 48-Pin SSOP M9999-030106 2 March 2006