LXT351PE Intel Corporation, LXT351PE Datasheet
LXT351PE
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LXT351PE Summary of contents
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LXT351 T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation The LXT351 is a full-featured, fully-integrated transceiver for T1 and E1 short-haul applications. The LXT351 is software switchable between T1 and E1 operation, and offers pulse equalization settings for all short-haul ...
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... 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. ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 Contents 1.0 Pin Assignments and Signal Descriptions 1.1 Mode Dependent Signals ...................................................................................... 9 2.0 Functional Description 2.1 Initialization..........................................................................................................13 2.1.1 Reset Operation .....................................................................................13 2.2 Transmitter ..........................................................................................................13 2.2.1 Transmit Digital Data Interface...............................................................13 ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation 5.0 Test Specifications 6.0 Mechanical Specifications Figures 1 LXT351 Block Diagram ......................................................................................... 7 2 LXT351 Pin Assignments...................................................................................... 8 3 50% Duty Cycle Coding ...................................................................................... 14 4 Local Loopback ................................................................................................... 16 ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 Tables 1 LXT351 Clock and Data Pin Assignments by Mode1............................................ 9 2 LXT351 Processor Interface Pins.......................................................................... 9 3 LXT351 Signal Descriptions ................................................................................10 4 Diagnostic Mode Summary .................................................................................16 5 Register Addresses ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Revision History Revision Date 6 Description Datasheet ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 Figure 1. LXT351 Block Diagram Datasheet 7 ...
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... Pin Assignments and Signal Descriptions Figure 2. LXT351 Pin Assignments RNEG / BPV RPOS / RDATA ALE / AS RNEG / BPV RPOS / RDATA ALE / LXT351PE XX LXT351PE RCLK 8 XXXXXX XXXXXXXX AD6 10 AD7 ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 1.1 Mode Dependent Signals As shown in Figure according to the selected mode(s) of operation. These pins, associated signal names, and operating modes are summarized in Table 1. LXT351 Clock ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Table 3. LXT351 Signal Descriptions Pin # Symbol PLCC QFP 1 39 MCLK 2 41 TCLK 3 42 TPOS / TDATA / INSLER TNEG / INSBPV ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 Table 3. LXT351 Signal Descriptions (Continued) Pin # Symbol PLCC QFP AD6 11 10 AD7 R TTIP ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Table 3. LXT351 Signal Descriptions (Continued) Pin # Symbol PLCC QFP 22 29 GND 23 31 AD0 24 32 AD1 25 35 AD2 26 36 AD3 27 37 AD4 28 ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 2.0 Functional Description The LXT351 is a fully integrated, PCM transceiver for short-haul, 1.544 Mbps (T1) or 2.048 Mbps (E1) applications allowing full-duplex transmission of digital data over existing twisted-pair ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation 2.2.2 Transmit Monitoring The transmitter includes a short circuit limiter that limits the current sourced into a low impedance load. The limiter automatically resets when the load current drops below ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 2.3 Receiver A 1:1 transformer provides the interface to the twisted-pair line. Recovered data is output at RPOS/ RNEG (RDATA in Unipolar mode), and the recovered clock is output at ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation 2.5 Diagnostic Mode Operation The LXT351 offers multiple diagnostic modes as listed in selected by setting the appropriate register bits as described in the following paragraphs. 2.5.1 Loopback Modes 2.5.1.1 ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 Table 4. Diagnostic Mode Summary Diagnostic Mode Internal Data Pattern Generation Transmit All Ones (TAOS) Quasi-Random Signal Source (QRSS) Error Insertion and Detection Bipolar Violation Insertion (INSBPV) Logic Error Insertion ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation 2.5.1.2 Analog Loopback See Figure 6. Analog loopback (ALOOP) exercises the maximum number of functional blocks. ALOOP operation disconnects the RTIP/RRING inputs from the line and routes the transmit outputs ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 Figure 7. Remote Loopback 2.5.1.4 Dual Loopback See Figure 8. To select Dual loopback (DLOOP) set bits CR2.ERLOOP and CR2.ELLOOP DLOOP mode, the transmit clock and data ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Figure 9. TAOS Data Path 2.5.2.2 Quasi-Random Signal Source (QRSS) See Figure 10. For T1 operation, the Quasi-Random Signal Source (QRSS random bit sequence (PRBS) with no ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 2.5.3 Error Insertion and Detection 2.5.3.1 Bipolar Violation Insertion Bipolar violation insertion is available In Unipolar mode. Choosing Unipolar mode configures the INSBPV pin. To insert bipolar violation (BPV), a ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation ZEROV detection is enabled when the HDB3 encoders/decoders are enabled. This requires CR1.ENCENB = 1, also CR1.EC3:1 = 000, which establishes E1 operation. To select ZEROV detection, set bit CR4.ZEROV ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 2.5.4.5 Built-In Self Test LXT351 provides a Built-In Self Test (BIST) capability. The BIST exercises the internal circuits by providing an internal QRSS pattern, running it through the encoders and ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation 3.0 Register Definitions The LXT351 contains five read/write and two read-only registers that are accessible via the parallel port. Table 5 lists the LXT351 register addresses. Only bits A6 through ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 Table 7. Control Register #1 Read/Write, Address (A7-A0) = x010000x Bit Name 0 EC1 Sets mode (T1 or E1) and equalizer 1 EC2 (see Table 8 2 EC3 3 - ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Table 9. Control Register #2 Read/Write, Address (A7-A0) = x010001x Bit Name 1 = Enable Transmit All Ones 4 ETAOS 0 = Disable Transmit All Ones 5 EPAT0 Selects internal ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 Table 11. Interrupt Clear Register Read/Write, Address (A7-A0) = x010011x Bit Name 1 = Clear/Mask Driver Failure Monitor Open interrupt. 5 CDFMO 0 = Enable Driver Failure Monitor Open interrupt. ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Table 13. Performance Status Register Read Only, Address (A7-A0) = x010101x Bit Name 1 = Driver Failure Monitor Open detected. 5 DFMO 0 = Driver Failure Monitor Open not detected. ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 4.0 Application Information 4.1 Transmit Return Loss Table 15 shows the specification for transmit return loss in E1 applications. The G.703/CH PTT specification is a Swiss Telecommunications Ministry specification. Table ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Table 16. Transmit Return Loss (2.048 Mbps) EC3-1 Xfrmr/Rt 1:2/ 9.1 000 1:2.3/9.1 Table 17. Transmit Return Loss (1.544 Mbps) EC3-1 Xfrmr/Rt 1:2/ 9.1 2 011 1 1:1.15 0.0 1. ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 Table 19. Recommended Transformers Tx/Rx Turns Ratio 1:1.15 Tx 1:2 1:2.3 Rx 1:1 4.4.1 LXT351 Application Circuit Figure 11 shows a typical application using the LXT351. See transformers (T1 and ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Figure 11. Typical T1/E1 LXT351 Application 2.048 MHz/ 1.544 MHz TCLK TPOS T1/E1 TNEG Framer RCLK RPOS RNEG 68 F 0.1 F NOTES: 1. See 100 L ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 5.0 Test Specifications Note: Table 20 through Table 31 specifications of the LXT350/351 and are guaranteed by test except, where noted, by design. The minimum and maximum values listed in ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Table 22. DC Electrical Characteristics Parameter Digital I/O pins 2 High level input voltage (pins 1-5, 9-12, 17, 23-28) 2 Low level input voltage (pins 1-5, 9-12, 17, 23-28) 2 ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 Figure 12. 2.048 Mbps E1 Pulse (See Table 24 100% 50% 0% Table 24. 2.048 Mbps E1 Pulse Mask Specifications Parameter Test load impedance Nominal peak mark voltage ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Figure 13. 1.544 Mbps T1 Pulse, DSX-1 (See Table 25) 1.5 Normalized Amplitude 1.0 0.5 -0.5 0.0 -0.5 0 Table 25. 1.544 Mbps T1, DSX-1 Pulse Mask Corner Point Specifications ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 Table 26. Master and Transmit Clock Timing Characteristics for T1 Operation (See Figure 14) Parameter Master clock frequency Master clock tolerance Master clock duty cycle Transmit clock frequency Transmit clock ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Table 28. Receive Timing Characteristics for T1 Operation (See Figure 15) Parameter 2, 3 Receive clock duty cycle 2, 3 Receive clock pulse width Receive clock pulse width High 1,3 ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 Table 30. 20 MHz Intel Bus Parallel I/O Timing Characteristics (See Figure 16) Parameter ALE pulse width Address valid to ALE falling edge ALE falling edge to address hold time ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Figure 16. Intel Address/Data Bus Timing 0ns 50ns CS T LHLL T LLAX ALE T AVLL RD AD0-7_R WR AD0-7_W Table 31. 16.78 MHz Motorola Bus Parallel I/O Timing Characteristics ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 Figure 17. Motorola Address/Data Bus Timing CS T ASHASL T AVASL AS DS R/W_Read AD0-7_Read R/W_Write AD0-7_Write Figure 18. Typical T1 Jitter Tolerance 1000 UI 500 UI ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Figure 19. Typical E1 Jitter Tolerance Datasheet ...
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T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 Figure 20. Typical E1 Jitter Attenuation Datasheet 43 ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Figure 21. Typical T1 Jitter Attenuation 44 Datasheet ...
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... T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation — LXT351 6.0 Mechanical Specifications Figure 22. Plastic Leaded Chip Carrier Package Specifications 28-Pin PLCC • Part Number LXT351PE • Extended Temperature Range (-40 ° ° Dim BSC—Basic Spacing between Centers. ...
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LXT351 — T1/E1 Short Haul Transceiver with Crystal-less Jitter Attenuation Figure 23. Plastic Quad Flat Package Specifications 44-Pin PQFP • • Dim ...