KSZ8721B Micrel Inc, KSZ8721B Datasheet

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KS8721B/BT General Description Operating at 2.5 volts to meet low voltage and low power requirements, the KS8721B/ 10BaseT/100BaseTX/ FX Physical Layer Transceiver, which provides an MII to transmit and receive data. It contains the 10BaseT Physical Medium Attachment ...

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... Part Number Temperature Range KS8721B 0°C to +70°C KS8721BI –40°C to +85°C KSZ8721B 0°C to +70°C KS8721BT 0°C to +70°C KSZ8721BT 0°C to +70°C 2 Micrel, Inc. Package 48-Pin SSOP 48-Pin SSOP 48-Pin SSOP Lead Free 48-Pin TQFP 48-Pin TQFP Lead Free ...

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KS8721B/BT Revision History Revision Date Summary of Changes 1.0 2/29/02 Document Origination (Preliminary) 2.0 4/01/02 Update timing Spec from page 33 to page 37 Change Revision ID from 1000 to 1001 Add new control register bit, Control Register 0 Bit ...

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KS8721B/BT Table Of Contents Pin Description ............................................................................................................................................................ 6 Strapping Option ......................................................................................................................................................... 9 Pin Configuration ...................................................................................................................................................... 10 Introduction ........................................................................................................................................................... 11 100BaseTX Transmit ........................................................................................................................................... 11 100BaseTX Receive ............................................................................................................................................ 11 PLL Clock Synthesizer ......................................................................................................................................... 11 Scrambler/De-scrambler (100BaseTX only) ........................................................................................................ 11 10BaseT Transmit ............................................................................................................................................... ...

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KS8721B/BT Absolute Maximum Ratings ..................................................................................................................................... 22 Operating Ratings ..................................................................................................................................................... 22 Electrical Characteristics .......................................................................................................................................... 22 Timing Diagrams ....................................................................................................................................................... 24 Selection of Isolation Transformers ........................................................................................................................ 30 Selection of Reference Crystals ............................................................................................................................... 30 Package Outline and Dimensions ............................................................................................................................ 31 April 2005 5 Micrel, ...

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KS8721B/BT Pin Description Pin Number Pin Name Type 1 MDIO 2 MDC 3 RXD3/ Ipd/O PHYAD1 4 RXD2/ Ipd/O PHYAD2 5 RXD1/ Ipd/O PHYAD3 6 RXD0/ Ipd/O PHYAD4 7 VDDIO 8 GND GND 9 RXDV/ Ipd/O CRSDV/ PCS_LPBK 10 RXC ...

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KS8721B/BT Pin Number Pin Name Type 25 INT#/ Ipu/O PHYAD0 22 CRS/ Ipd/O RMII_BTB 23 GND GND 26 LED0/TEST Ipu/O 27 LED1/ Ipu/O SPD100/ noFEF 28 LED2/ Ipu/O DUPLEX 29 LED3/ Ipu/O NWAYEN 30 PD# 31 VDDRX 32 RX- 33 ...

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KS8721B/BT Pin Number Pin Name Type 37 REXT 38 VDDRCV 39 GND GND 40 TX- 41 TX+ 42 VDDTX 43 GND GND 44 GND GND VDDPLL 48 RST# Note 1. Pwr = power supply GND ...

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KS8721B/BT (Note 1) Strapping Options Pin Number Pin Name Type 6,5, PHYAD[4:1]/ Ipd/O 4,3 RXD[0:3] 25 PHYAD0/ Ipu/O INT# (3) 9 PCS_LPBK/ Ipd/O RXDV (3) 11 ISO/RXER Ipd/O (3) 21 RMII/COL Ipd/O (3) 22 RMII_BTB Ipd/O CRS 27 SPD100/ Ipu/O ...

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KS8721B/BT Pin Configuration MDIO 1 MDC 2 R3D3/PHYAD1 3 RXD2/PHYAD2 4 RXD1/PHYAD3 5 RXD0/PHYAD4 6 VDDIO 7 GND 8 RXDV/PCS_LPBK 9 RXC 10 RXER/ISO 11 GND 12 VDDC 13 TXER 14 TXC/REF_CLK 15 TXEN 16 TXD0 17 TXD1 18 TXD2 ...

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KS8721B/BT Introduction 100BaseTX Transmit The 100BaseTX transmit function performs parallel to serial conversion, NRZ to NRZI conversion, MLT-3 encoding and transmission. The circuitry starts with a parallel to serial conversion, which converts the 25MHz, 4-bit nibbles into a 125 MHz ...

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KS8721B/BT During auto-negotiation, the contents of Register 4, coded in Fast Link Pulse (FLP), will be sent to its link partner under the conditions of power-on, link-loss or re-start. At the same time, the KS8721B/BT will monitor incoming data to ...

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KS8721B/BT Collision: Whenever the line state is half-duplex and the transmitter and receiver are active at the same time, the KS8721B/ BT asserts its collision signal, which is asynchronous to any clock. RMII (Reduced MII) Data Interface RMII interface specifies ...

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KS8721B/BT Transmit Data [1:0] (TXD[1:0]) Transmit Data TXD[1:0] shall transition synchronously with respect to REF_CLK. When TX_EN is asserted, TXD[1:0] are accepted for transmission by the PHY. TXD[1:0] shall be “00” to indicate idle when TX_EN is de-asserted. Values of ...

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KS8721B/BT RMII Receive Timing REF_CLK RXD[1:0] RXDV RXER Parameter REF_CLK Frequency RXD[1:0], CRS_DV, RX_ER Output delay from REF_CLK rising edge Auto Crossover (Auto MDI/MDI-X) Automatic MDI/MDI-X configuration is intended to eliminate the need for crossover cables between similar devices. The ...

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KS8721B/BT Power Management The KS8721B/BT offers the following modes for power management: • Power Down Mode: This mode can be achieved by writing to Register 0.11 or pulling pin 30 PD# Low. • Power Saving Mode: This mode can be ...

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KS8721B/BT Register Map Register No. Description 0h Basic Control Register 1h Basic Status Register 2h PHY Identifier I 3h PHY Identifier II 4h Auto-Negotiation Advertisement Register 5h Auto-Negotiation Link Partner Ability Register 6h Auto-Negotiation Expansion Register 7h Auto-Negotiation Next Page ...

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KS8721B/BT Address Name 1.10:7 Reserved 1.6 No Preamble 1.5 Auto-Negotiation Complete 1.4 Remote Fault 1.3 Auto-Negotiation Ability 1.2 Link Status 1.1 Jabber Detect 1.0 Extended Capability Register 2h - PHY Identifier 1 2.15:0 PHY ID Number Register 3h - PHY ...

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KS8721B/BT Address Name 5.11:10 Pause 5.9 100 BaseT4 5.8 100BaseTX Full Duplex 5.7 100BaseTX 5.6 10BaseT Full Duplex 5.5 10BaseT 5.4:0 Selector Field Register 6h - Auto-Negotiation Expansion 6.15:5 Reserved 6.4 Parallel Detection Fault 6.3 Link Partner Next Page Able ...

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KS8721B/BT Address Name Register 15h - RXER Counter 15.15:0 RXER Counter Register 1bh - Interrupt Control/Status Register 1b.15 Jabber Interrupt Enable 1b.14 Receive Error Interrupt Enable 1b.13 Page Received Interrupt Enable 1b.12 Parallel Detect Fault Interrupt Enable 1b.11 Link Partner ...

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KS8721B/BT Address Name 1f.6 Enable Pause (Flow-Control Result) 1f.5 PHY Isolate 1f.4:2 Operation Mode Indication [000] = still in auto-negotiation 1f.1 Enable SQE Test 1f.0 Disable Data Scrambling Note 1. RW: Read/Write, RO: Read only, SC: Self clear, LH: Latch ...

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KS8721B/BT Absolute Maximum Ratings Supply Voltage ( DDC DD_PLL DD_TX DD_RCV V ) ................................................... –0.5V to +3.0V DD_RX (V ) .................................................... –0.5V to +4.0V DDIO Input Voltage ............................................... –0.5V to +4.0V Output Voltage ............................................ ...

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KS8721B/BT Symbol Parameter 10BaseTX Receive R RX+/RX– Differential IN Input Resistance V Squelch Threshold SQ 10BaseTX Transmit (measured differentially after 1:1 transformer) V Peak Differential Output Voltage P Jitters Added Rise/Fall Time r t Clock Outputs X1, ...

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KS8721B/BT Timing Diagrams TXC TXEN TXD[3:0] CRS TXP/TXM SQE Timing TXC TXEN COL Symbol Parameter t TXD [3:0] Set-Up to TXC High SU1 t TXEN Set-Up to TXC High SU2 t TXD [3:0] Hold After TXC High HD1 t TXEN ...

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KS8721B/BT TXC TXEN TXD[3:0], TXER CRS TX+/TX- Symbol Parameter t TXD [3:0] Set-Up to TXC High SU1 t TXEN Set-Up to TXC High SU2 t TXD [3:0] Hold After TXC High HD1 t TXER Hold After TXC High HD2 t ...

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KS8721B/BT Start of RX+/RX- Stream CRS RXDV RXD[3:0] RXER RXC Symbol Parameter t RXC Period P t RXC Pulse Width WL t RXC Pulse Width WH t RXD [3:0], RXER, RXDV Set-Up to Rising Edge of RXC SU t RXD ...

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KS8721B/BT TX+/TX- TX+/TX- Figure 7. Auto-Negotiation/Fast Link Pulse Timing Symbol Parameter t FLP Burst to FLP Burst BTB t FLP Burst Width FLPW t Clock/Data Pulse Width PW t Clock Pulse to Data Pulse CTD t Clock Pulse to Clock ...

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KS8721B/BT MDC MDIO (Into Chip) MDIO (Out of Chip) Symbol Parameter t MDC Period P t MDIO Set-Up to MDC (MDIO as input) MD1 t MDIO Hold after MDC (MDIO as input) MD2 t MDC to MDIO Valid (MDIO as ...

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KS8721B/BT Supply Voltage RST_N Strap-In Value Strap-In / Output Pin Symbol Parameter t Stable Supply Voltages to Reset High sr t Configuration Set-Up Time cs t Configuration Hold Time ch t Reset to Strap-In Pin Output rc Reset Circuit Diagram ...

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KS8721B/BT Selection of Isolation Transformer One simple 1:1 isolation transformer is needed at the line interface. An isolation transformer with integrated common-mode choke is recommended for exceeding FCC requirements. The following table gives recommended transformer characteristics. Characteristics Name Turns Ratio ...

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KS8721B/BT Package Information April 2005 48-Pin SSOP (SM) 31 Micrel, Inc. M9999-041405 ...

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... KS8721B/BT MICREL INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA + 1 (408) 944-0800 TEL This information furnished by Micrel in this data sheet is believed to be accurate and reliable. However no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. ...