LXT908LE Intel Corporation, LXT908LE Datasheet
LXT908LE
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LXT908LE Summary of contents
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LXT908 Universal 3.3V 10BASE-T and AUI Transceiver The LXT908 Universal 10BASE-T and AUI Transceiver is designed for IEEE 802.3 physical layer applications. It provides all the active circuitry to interface most standard 802.3 controllers to either the 10BASE-T media or ...
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... Contact your local Intel sales office or your distributor to obtain the latest specifications and before placing your product order. Copies of documents which have an ordering number and are referenced in this document, or other Intel literature may be obtained by calling 1-800-548-4725 or by visiting Intel’s website at http://www.intel.com. Copyright © Intel Corporation, 2001 *Third-party brands and names are the property of their respective owners. 2 ® ...
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Contents 1.0 Pin Assignments and Signal Descriptions 2.0 Functional Description 2.1 Introduction.......................................................................................................... 11 2.1.1 Controller Compatibility Modes .............................................................. 11 2.1.2 Transmit Function................................................................................... 12 2.1.3 Jabber Control Function ......................................................................... 12 2.1.4 Receive Function.................................................................................... 13 2.1.5 SQE Function ......................................................................................... 13 2.1.6 Polarity ...
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Contents Figures 1 LXT908 Block Diagram ......................................................................................... 7 2 LXT908 Pin Assignments ...................................................................................... 8 3 LXT908 TPO Output Waveform ......................................................................... 12 4 Jabber Control Function...................................................................................... 13 5 SQE Function ..................................................................................................... 14 6 Collision Detection Function ............................................................................... 15 7 Transmitted Link ...
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Tables 1 LXT908 Signal Descriptions .................................................................................. 9 2 Controller Compatibility Mode Options................................................................ 12 3 Suitable Crystals ................................................................................................ 18 4 Absolute Maximum Values................................................................................. 26 5 Recommended Operating Conditions ................................................................ 26 6 I/O Electrical Characteristics .............................................................................. 26 7 AUI Electrical Characteristics ............................................................................. ...
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Contents Revision History Date Revision June 2001 2001 6 Page Description 1 Added new set of applications 19 Added 01. F label to capacitor at bottom of Figure 9 20 Added 01. F label to capacitor at bottom of Figure ...
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Figure 1. LXT908 Block Diagram AUTOSEL MODE SELECT LOGIC Controller PAUI Compatibility/ Port Select / LBK Loopback / LI Link test TCLK CLKI XTAL OSC CLKO MANCHESTER ENCODER TEN TXD CD SQUELCH / LINK LEDL DETECT RXD MANCHESTER RCLK DECODER ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver 1.0 Pin Assignments and Signal Descriptions Figure 2. LXT908 Pin Assignments n JAB 9 TEST 10 11 TCLK LXT908PC/PE XX TXD 12 Part # LOT # XXXXXX TEN 13 ...
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Table 1. LXT908 Signal Descriptions Pin# Symbol PLCC LQFP – 16, 17, 18, 20, 30, 31, 32, 33 ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver Table 1. LXT908 Signal Descriptions (Continued) Pin# Symbol PLCC LQFP LEDT LEDC – 40 GNDA 24 42 RBIAS 26 45 ...
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Table 1. LXT908 Signal Descriptions (Continued) Pin# Symbol PLCC LQFP 2.0 Functional Description 2.1 Introduction The LXT908 Universal 10BASE-T and AUI Transceiver performs the physical layer signaling (PLS) and Media ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver 2.1.2 Transmit Function The LXT908 receives NRZ data from the controller at the TXD input as shown in “LXT908 Block Diagram” on page data is then transferred to either the AUI cable ...
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Figure 4. Jabber Control Function Nonjabber Output Start_XMIT_MAX_Timer DO=Idle XMIT=Disable LPBK=Disable Unjab Wait Start_Unjab_Timer XMIT=Disable LPBK=Disable Unjab_ Timer_Done 2.1.4 Receive Function The LXT908 receive function acquires timing and data from the twisted-pair network (TPI circuit) or from the AUI (DI ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver SQE must be disabled for normal operation in hub and switch applications. In twisted-pair applications, the SQE function is disabled when DSQE is set High, and enabled when DSQE is Low. When ...
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The LXT908 also provides three additional loopback functions. An external loopback mode, useful for system-level testing, is controlled by pin 21 (LEDC). When LEDC is tied Low, the LXT908 disables the collision detection and internal loopback circuits, to allow external ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver 2.1.9 Link Pulse Transmission The LXT908 transmits standard link pulses which meet the 10BASE-T specifications. shows the link integrity pulse timing. Figure 7. Transmitted Link Integrity Pulse Timing 10-20 ms 10-20 ms ...
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Figure 8. Link Integrity Test Function Power On Idle Test Start_Link_Loss_Timer Start_Link_Test_Min_Timer Link_Loss_Timer_Done TPI=Idle Link_Test_Rcvd=False Link Test Fail Reset Link_Count=0 XMIT=Disable RCVR=Disable LPBK=Disable TPI=Active Link_Test_Rcvd=False TPI=Idle Link Test Fail Extended XMIT=Disable RCVR=Disable LPBK=Disable TPI=Idle DO=Idle Datasheet Document #: 249049 Revision ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver 3.0 Application Information Figure 9 on page 19 through 3.1 External Components 3.1.1 Crystal Information Suitable crystals are available from various manufacturers. limited evaluation. Designers should test and validate all crystals before ...
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Status outputs are grouped at the lower left of the diagram. Line status outputs drive LED indicators and the Jabber and Polarity status indicators are available, as required. Power and ground pins are shown at the bottom of the diagram. ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver 3.2.2 Full Duplex Support Figure 10 shows the LXT908 with a Texas Instruments 380C24 CommProcessor. The 380C24 is compatible with Mode 4 (MD2:0 = Low, High, High). When used with the 380C24 ...
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Dual Network Support-10Base T and Token Ring Figure 11 shows the LXT908 with a Texas Instruments 380C26 CommProcessor. The 380C26 is compatible with Mode 4 (MD2:0 = Low, High, High). When used with the 380C26, both the LXT908 and ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver 3.2.4 Manual Port Select & Link Test Function When MD2:0 = Low, High, Low, the LXT908 logic and framing are set to Mode 3 (compatible with Fujitsu MB86950 and MB86960, and Seeq ...
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Figure 13. Manual Port Select with Seeq 8005 Controller External 20 MHz Source CLKI CLKI LPBK LBK CSN CD 8005 RxD RXD RxC RCLK COLL COL TxEN TEN TCLK TxC TXD TxD PAUI Port Selection AUTOSEL NTH PROGRAMMING DSQE OPTIONS ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver 3.2.5 Three Media Application Figure 14 shows the LXT908 in Mode 2 (compatible with Intel 82596 controllers) with additional media options for the AUI port. Two transformers are used to couple the ...
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AUI Encoder/Decoder Only In the application shown in AUTOSEL is tied Low and PAUI is tied High, manually selecting the AUI port. The twisted-pair port is not used. With MD2:0 all tied Low, the LXT908 logic and framing are ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver 4.0 Test Specifications Note: Table 4 through Table 13 on page 29 represent the performance specifications of the LXT908. These specifications are guaranteed by test except where noted “by design.” Minimum and ...
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Table 6. I/O Electrical Characteristics (Continued) Parameter Output fall time TCLK & RCLK CLKI rise time (externally driven) CLKI duty cycle (externally driven) Normal Mode Supply current Power Down 1. Typical values are at 25°C and are for design aid ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver Table 8. Twisted-Pair Electrical Characteristics (Continued) Parameter Receive input impedance Differential Squelch Threshold 1. Typical values are at 25°C and are for design aid only, are not guaranteed, and are not subject ...
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Table 11. RCLK/End-of-Frame Timing Parameter RCLK after CD off RXD throughput delay 2 CD turn off delay Receive block out after TEN off RCLK switching delay after CD off (Mode 3 and 5) 1. Typical values are at 25°C and ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver 4.1 Timing Diagrams for Mode 1 (MD2 Low, Low, Low) Figures Figure 16. Mode 1 RCLK/Start-of-Frame Timing TPIP/TPIN or DIP/DIN t CD ...
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Figure 18. Mode 1 Transmit Timing TEN t TCLK TXD TPO Figure 19. Mode 1 Collision Detect Timing CI t COLD COL Figure 20. Mode 1 COL/SQE Output Timing/CI Output Timing TEN COL Figure 21. Mode 1 Loopback Timing LBK ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver 4.2 Timing Diagrams for Mode 2 (MD2 Low, Low, High) Figures Figure 22. Mode 2 RCLK/Start-of-Frame Timing TPIP/TPIN or DIP/DIN t ...
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Figure 24. Mode 2 Transmit Timing TEN TCLK TXD TPO Figure 25. Mode 2 Collision Detect Timing CI t COLD COL Figure 26. Mode 2 COL/SQE Output Timing TEN COL Figure 27. Mode 2 Loopback Timing LBK t KHEH TEN ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver 4.3 Timing Diagrams for Mode 3 (MD2 Low, High, Low) Figures Figure 28. Mode 3 RCLK/Start-of-Frame Timing TPIP/TPIN or DIP/DIN t ...
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Figure 30. Mode 3 Transmit Timing TEN TCLK TXD TPO Figure 31. Mode 3 Collision Detect Timing CI t COLD COL Figure 32. Mode 3 COL/SQE Output Timing TEN COL Figure 33. Mode 3 Loopback Timing LBK t KHEH TEN ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver 4.4 Timing Diagrams for Mode 4 (MD2 Low, High, High) Figures Figure 34. Mode 4 RCLK/Start-of-Frame Timing TPIP/TPIN or DIP/DIN t ...
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Figure 36. Mode 4 Transmit Timing TEN TCLK TXD TPO Figure 37. Mode 4 Collision Detect Timing CI t COLD COL Figure 38. Mode 4 COL/SQE Output Timing TEN COL Figure 39. Mode 4 Loopback Timing LBK t KHEH TEN ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver 4.5 Timing Diagrams for Mode 5 (MD2 High, High, Low) Figures Figure 40. Mode 5 RCLK/Start-of-Frame Timing TPIP/ TPIN t CD ...
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Figure 42. Mode 5 Transmit Timing TEN TCLK TXD TPO Figure 43. Mode 5 Collision Detect Timing CI t COLD COL Figure 44. Mode 5 COL/SQE Output Timing TEN COL Figure 45. Mode 5 Loopback Timing LBK t KHEH TEN ...
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LXT908 — Universal 3.3V 10BASE-T and AUI Transceiver 5.0 Mechanical Specifications Figure 46. 44-Pin PLCC Package Specifications • Part Number LXT908PC - Commercial temperature range ( +70 C) • Part Number LXT908PE - Extended temperature range (-40 C ...
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... Figure 47. 64-Pin LQFP Package Specifications • Part Number LXT908LC (Commercial Temperature Range) • Part Number LXT908LE (Extended Temperature Range) Inches Dim Min Max A – 0.063 A1 0.002 0.006 A2 0.053 0.057 B 0.007 .011 D 0.472 BSC D1 0.394 BSC E 0.472 BSC E1 0.394 BSC e 0.020 BSC L 0 ...
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... Appendix A Ordering Information Table 14. Product Information Number DJLXT908LC.A4 DJLXT908LE.A4 NLXT908PC.A4 NLXT908PE.A4 Figure 48. Ordering Information - Sample DJ LXT 908 L Datasheet Document #: 249049 Revision #: 002 Rev. Date: June 19, 2001 Universal 3.3V 10BASE-T and AUI Transceiver — LXT908 Revision Qualification E001 Build Format = Tray E000 ...
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