Advance Information This document contains information on a product under development. The parametric information contains target parameters that are subject to change. CN8331/CN8332/CN8333 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit The CN8333 is a three-channel, E3/DS3/STS-1 fully-integrated Line Interface Unit (LIU). It is configured via external pins and does not need a microprocessor interface. Each channel has an independent equalizer on the receive side requiring no user configuration. Also, each channel has a programmable transmit pulse shaper that can be set to ensure that the cross-connect pulse mask requirement is met for transmit cable length up to 450 feet. The CN8332 is a dual-channel, and the CN8331 is a single-channel LIU with performance identical to the CN8333. The CN8333 gives the user new economies of scale in concentrator applications where three DS3 or STS-1 channels are concentrated into a single STS-3 channel. By including three independent transceivers on a chip, significant external components are eliminated, with the exception of 1:1 coupling transformers, termination resistors, and supply bypass capacitors. NOTE: • • • • • • Functional Block Diagram (only one Channel is shown) • XOE LBO E3MODE • PDB • Pulse Shaper ENCODER LINE DRIVER TLINEP TLINEM TCLK DATA MUX Can be used as a data transceiver over a maximum of 900 feet of Type 734/728 coaxial cable or equivalent in an on-premise environment Programmable pulse filtering to meet cross-connect pulse masks (ANSI T1.102-1993) Meets jitter specifications of Bellcore GR499 and GR253 Large input dynamic range Alarms for coding violation and loss of signal Full diagnostic loopback capability Uses a minimum of external components Compatible with ITU-T G.703, G.823 Independent power down mode per channel Easily interfaced to the DS3/E3 Framer IC (CN8342/3/4/6/8 and CN8330) Selectable B3ZS/HDB3 encoding/decoding Superior input receiver sensitivity (< 25mV) Physical Characteristics • • • • • • ENDECDIS TAIS RLOOP LLOOP • • • In this document "x" is used to represent the number of channels: x = 1 (CN8331), x = 2 (CN8332), and x = 3 (CN8333). TPOS TNEG TCLK Distinguishing Features 80-pin ETQFP package Single 3.3 V power supply 1 W maximum power dissipation (CN8333) –40 °C to +85 °C temperature range 5 V-tolerant pins TTL digital pins REFCLK Applications RPOS RNEG RCLK RLOS Data Sheet DECODER PDATA Clock/ NDATA Data DATCLK Recovery P N Receiver ALOS RLINEP RLINEM REQH • • • • • • • Digital Cross Connect Systems Routers ATM Switches Channelized Line Aggregation Units Test Equipment Channel Service Units Multiplexers 100604B March 23, 2000 CN8333EVM TX B3ZS/HDB3 analog out NRZTX DATA and CLK in CH1 CH1 NRZRX DATA and CLK out F R A M E S I D E RX B3ZS/HDB3 analog in TX B3ZS/HDB3 analog out NRZTX DATA and CLK in CH2 CN8333 NRZRX DATA and CLK out CH2 RX B3ZS/HDB3 analog in TX B3ZS/HDB3 analog out NRZTX DATA and CLK in CH3 CH3 NRZRX DATA and CLK out L I N E S I D E RX B3ZS/HDB3 analog in Loss of Signal Clock Input Code Violation Control 100604_009 Ordering Information Model Number Package Operating Temperature CN8331EXF CN8332EXF CN8333EXF 80-Pin ETQFP 80-Pin ETQFP 80-Pin ETQFP –40 °C to 85 °C –40 °C to 85 °C –40 °C to 85 °C © 2000, Conexant Systems, Inc. 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For technical questions, contact your local Conexant sales office or field applications engineer. 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential Table of Contents Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii 1.0 Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 1.1 2.0 Pin Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 2.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 2.2 Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3 2.2.1 2.2.2 2.2.3 2.2.4 2.2.5 2.2.6 2.3 Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9 2.3.1 2.3.2 2.3.3 2.3.4 2.3.5 2.3.6 2.3.7 2.3.8 2.4 AMI B3ZS/HDB3 Encoder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3 Pulse Shaper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4 Line Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5 Transmit Pulse Mask Templates and Power Measurements . . . . . . . . . . . . . . . . . . . . . . . 2-6 Alarm Indication Signal (AIS) Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8 Jitter Generation (Intrinsic) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8 Receive Sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9 AGC/VGA Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9 Receive Equalizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9 The PLL Clock Recovery Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10 Loss Of Signal (LOS) Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10 Jitter Tolerance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10 B3ZS/HDB3 Decoder With Bipolar Violation Detector . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12 Data Squelching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12 Additional CN8331/CN8332/CN8333 Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13 2.4.1 2.4.2 2.4.3 Bias Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13 Power-On Reset (POR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13 Loopback Multiplexers (MUXes) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13 2.5 Mechanical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14 2.6 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential iii CN8331/CN8332/CN8333 Table of Contents Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.6.1 2.6.2 3.0 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15 Recommended Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16 2.7 DC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17 2.8 AC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 3.1 PCB Design Considerations for CN8331/CN8332/CN8333 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 3.1.1 3.1.2 3.1.3 3.1.4 3.1.5 Power Supply and Ground Plane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 Impedance Matching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 Other Passive Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 IBIS Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 Recommended Vendors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 Appendix A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1 A.1 Applicable Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1 Appendix B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1 B.1 iv Evaluation Module Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1 Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B CN8331/CN8332/CN8333 List of Figures Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit List of Figures Figure 1-1. Figure 1-2. Figure 1-3. Figure 2-1. Figure 2-2. Figure 2-3. Figure 2-4. Figure 2-5. Figure 2-6. Figure 2-7. Figure 2-8. Figure 2-9. Figure 3-1. Figure B-1. 100604B CN8331 Pin Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 CN8332 Pin Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3 CN8333 Pin Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4 Typical Application Of Single CN833x Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2 Pulse Shaper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4 Pulse Measurement Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5 Transmit Pulse Mask for E3 Rate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6 Transmit Pulse Mask for DS3 and STS-1 Rates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7 AIS Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8 Minimum Input Jitter Tolerance Requirement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11 Mechanical Drawing—Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14 Timing Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19 Typical Connection of CN8333 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3 Recommended Schematic for the CN833x Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-2 Conexant Preliminary Information/Conexant Proprietary and Confidential v CN8331/CN8332/CN8333 List of Figures Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit vi Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B CN8331/CN8332/CN8333 List of Tables Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit viii Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B 1 1.0 Pin Description 1.1 Pin Assignments Figures 1-1 (CN8331), 1-2 (CN8332), and 1-3 (CN8333) illustrate pin assignments for the 80-pin Exposed Thin Quad Flat Package (ETQFP). Table 1-1 lists the pin definitions and gives additional information for each pin. The input/output (I/O) column is coded as follows: I = Input O = Output I/O = Bidirectional P = Power When a channel is disabled (i.e., the PDBx pin is tied low or not connected), all receive and transmit analog circuitry powers down. Analog inputs (RLINE) are ignored and analog outputs (TLINE) are high impedance. Digital inputs of a powered-down channel are still active, but ignored. Overall noise on the device can be lowered by not driving the digital inputs of a powered-down channel. NOTE: 100604B When power is disconnected from the device, TLINE pins are low impedance to ground if driven by more than one forward-bias diode voltage (0.7 V) below ground. Additionally, driving TLINE, a forward-bias diode voltage above the VGG pin, creates a low impedance path from the TLINE pin to the VGG pin. Otherwise, the TLINE pins are high impedance. Conexant Preliminary Information/Conexant Proprietary and Confidential 1-1 1.0 Pin Description CN8331/CN8332/CN8333 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 1.1 Pin Assignments RBIAS VGG RESET GPD NC NC NC DVDDIO NC NC NC NC NC NC NC NC NC NC NC NC 80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 64 63 62 61 Figure 1-1. CN8331 Pin Diagram VSS 1 60 DVDDC NC 2 59 ENDECDIS NC 3 58 PD VDD 4 57 RLOOP VDD 5 56 LLOOP NC 6 55 RNEG/RLCV NC 7 54 RPOS/RNRZ VSS 8 53 RCLK TVSS 9 52 RLOS TLINEP 10 51 TAIS TLINEN 11 50 TCLK TVDD 12 49 TPOS/TNRZ RVDD 13 48 TNEG/NC RLINEP 14 47 REFCLK RLINEN 15 46 REQH RVSS 16 45 XOE VSS 17 44 LBO NC 18 43 E3MODE NC 19 42 NC VDD 20 41 DVSSC 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 VDD NC NC VSS NC NC NC DVSSIO NC NC NC NC NC NC NC NC NC NC NC NC CN8331 100604_002 1-2 Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B NC NC VDD VDD NC NC VSS RVSS1 RLINE1N RLINE1P RVDD1 TVDD1 TLINE1N TLINE1P TVSS1 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 VGG RLINE2N 23 78 RESET RVSS2 24 77 GPD PD2 25 76 PD1 RLOOP2 26 75 RLOOP1 LLOOP2 27 74 LLOOP1 DVSSIO 28 73 DVDDIO LBO2 29 72 LBO1 XOE2 30 71 XOE1 REQH2 31 70 REQH1 RNEG2/RLCV2 32 69 RNEG1/RLCV1 RPOS2/RNRZ2 33 68 RPOS1/RNRZ1 RCLK2 34 67 RCLK1 RLOS2 35 66 RLOS1 REFCLK2 36 65 REFCLK1 TNEG2/NC2 37 64 TNEG1/NCI TPOS2/TNRZ2 38 63 TPOS1/TNRZ1 TCLK2 39 62 TCLK1 TAIS2 40 61 TAIS1 CN8332 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 DVSSC NC E3MODE NC NC NC NC NC NC NC NC NC NC NC NC NC NC NC ENDECDIS DVDDC 1.0 Pin Description VSS 18 42 CN8331/CN8332/CN8333 TVSS2 19 41 1.1 Pin Assignments TLINE2P 20 RBIAS 79 Conexant 1-3 100604_010 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit TVDD2 80 22 Preliminary Information/Conexant Proprietary and Confidential TLINE2N 21 Figure 1-2. CN8332 Pin Diagram 100604B RVDD2 RLINE2P 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 DVSSC NC E3MODE LBO2 XOE2 REQH2 REFCLK2 TNEG2/NC2 TPOS2/TNRZ2 TCLK2 TAIS2 RLOS2 RCLK2 RPOS2/RNRZ2 RNEG2/RLCV2 LLOOP2 RLOOP2 PD2 ENDECDIS DVDDC CN8331/CN8332/CN8333 1 42 1.0 Pin Description TVSS1 2 41 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit TLINE1P 3 VGG RLINE3N 23 78 RESET RVSS3 24 77 GPD PD3 25 76 PD1 RLOOP3 26 75 RLOOP1 LLOOP3 27 74 LLOOP1 DVSSIO 28 73 DVDDIO LBO3 29 72 LBO1 XOE3 30 71 XOE1 REQH3 31 70 REQH1 RNEG3/RLCV3 32 69 RNEG1/RLCV1 RPOS3/RNRZ3 33 68 RPOS1/RNRZ1 RCLK3 34 67 RCLK1 RLOS3 35 66 RLOS1 REFCLK3 36 65 REFCLK1 TNEG3/NC3 37 64 TNEG1/NCI TPOS3/TNRZ3 38 63 TPOS1/TNRZ1 TCLK3 39 62 TCLK1 TAIS3 40 61 TAIS1 CN8333 RBIAS 79 Conexant 100604B 100604_011 1.1 Pin Assignments TLINE1N 4 10 TVDD1 11 5 TLINE2P 12 RVDD1 TLINE2N 13 6 TVDD2 14 RLINE1P RVDD2 15 7 RLINE2P 16 RLINE1N RLINE2N 17 8 RVSS2 18 RVSS1 TVSS3 19 9 TLINE3P 20 TVSS2 TVDD3 80 22 Preliminary Information/Conexant Proprietary and Confidential TLINE3N 21 Figure 1-3. CN8333 Pin Diagram 1-4 RVDD3 RLINE3P CN8331/CN8332/CN8333 1.0 Pin Description Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 1.1 Pin Assignments Table 1-1. CN8331/CN8332/CN8333 Pin Definitions (1 of 6) Pin # Signal Name CN8331 CN8332 Description I/O/P Notes Differential inputs for each channel from its respective receive coax line. The RX expects balanced differential inputs, usually achieved using a 1:1 transformer. The inputs are internally DC biased to 1.9 V. CN8333 Coaxial Line Pins 14 6 6 RLINEP/ RLINE1P Line 1 positive receive data I 15 7 7 RLINEN/ RLINE1N Line 1 negative receive data I — 22 14 RLINE2P Line 2 positive receive data I — 23 15 RLINE2N Line 2 negative receive data I — — 22 RLINE3P Line 3 positive receive data I — — 23 RLINE3N Line 3 negative receive data I 10 2 2 TLINEP/ TLINE1P Line 1 positive transmit data O 11 3 3 TLINEN/ TLINE1N Line 1 negative transmit data O — 18 10 TLINE2P Line 2 positive transmit data O — 19 11 TLINE2N Line 2 negative transmit data O — — 18 TLINE3P Line 3 positive transmit data O — — 19 TLINE3N Line 3 negative transmit data O Differential, coax-driver balanced outputs for pulse-shaped AMI B3ZS/HDB3 encoded waveforms for each channel. These pins should be connected to the primary side of the 1:1 transformer through two backmatch resistors (see Appendix B). Digital Data Pins 54 68 68 RPOS/ RPOS1/ RNRZ/ RNRZ1 RX1 AMI + data/ NRZ data output O 55 69 69 RNEG/ RNEG1/ RLCV/ RLCV1 RX1 AMI – data/line code violation O — 33 54 RPOS2/ RNRZ2 RX2 AMI + data/ NRZ data output O — 32 55 RNEG2/ RLCV2 RX2 AMI – data/line code violation O — — 33 RPOS3/ RNRZ3 RX3 AMI + data/ NRZ data output O — — 32 RNEG3/ RLCV3 RX3 AMI – data/line code violation O 100604B Powered by ICminer.com Electronic-Library Resynchronized receive data intended to be strobed out by the corresponding RCLK. When ENDECDIS = 1, these outputs are positive and negative AMI data (RPOS and RNEG). When ENDECDIS = 0, these outputs are decoded NRZ data (RNRZ) and line code violation (RLCV). A line code violation is indicated when RLCV = 1. See notes on the ENDECDIS pin, next page. Conexant Preliminary Information/Conexant Proprietary and Confidential Service CopyRight 2003 1-5 1.0 Pin Description CN8331/CN8332/CN8333 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 1.1 Pin Assignments Table 1-1. CN8331/CN8332/CN8333 Pin Definitions (2 of 6) Pin # Signal Name Description I/O/P Notes 67 RCLK/ RCLK1 Receive clock Ch1 O 34 53 RCLK2 Receive clock Ch2 O Recovered clock for each channel receiver, intended for strobing the corresponding RDAT into the following framer or logic. — — 34 RCLK3 Receive clock Ch3 O 49 63 63 TPOS/ TPOS1/ TNRZ/ TNRZ1 Ch1 transmit Positive rail or NRZ data I 48 64 64 TNEG/ TNEG1/ NC/ NC1 Ch1 transmit Negative rail or no connect data I — 38 49 TPOS2/ TNRZ2 Ch2 transmit Positive/NRZ data I — 37 48 TNEG2/ NC2 Ch2 transmit Negative data I — — 38 TPOS3/ TNRZ3 Ch3 transmit Positive/NRZ data I — — 37 TNEG3/ NC3 Ch3 transmit Negative data I 50 62 62 TCLK/ TCLK1 Transmit clock Ch1 I — 39 50 TCLK2 Transmit clock Ch2 I — — 39 TCLK3 Transmit clock Ch3 I 52 66 66 RLOS/ RLOS1 Loss of signal Ch1 O — 35 52 RLOS2 Loss of signal Ch2 O — — 35 RLOS3 Loss of signal Ch3 O CN8331 CN8332 CN8333 53 67 — 1-6 Synchronized transmit data intended to be strobed in by the corresponding TCLK. When ENDECDIS = 1, these inputs are expected to be positive and negative AMI data (TPOS and TNEG). When ENDECDIS = 0, these inputs are expected to be uncoded NRZ data (TNRZ) and no connects (NC). See notes on the ENDECDIS pin. Transmit bit clock input for strobing with transmit data into the CN833x. Loss Of Signal (LOS) indication for each channel, as determined by insufficient pulse density. Signal loss detected when RLOS = 1. An LOS will be asserted when 175±75 zeros occur in a row and deasserted when the pulse density is between 28% and 33% (DS3/STS-1) (i.e., a 1’s density). Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B CN8331/CN8332/CN8333 1.0 Pin Description Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 1.1 Pin Assignments Table 1-1. CN8331/CN8332/CN8333 Pin Definitions (3 of 6) Pin # Signal Name CN8331 CN8332 Description I/O/P Notes I 1 = Dual rail pulse coded data format. Input transmit data pins TPOS, TNRZ, TNEG and NC are interpreted as TPOS and TNEG (encoded positive and negative rail data). Output receive data pins RPOS and RNRZ, and RNEG and RLCV are interpreted as RPOS and RNEG, with RPOS having a positive pulse in place of every positive AMI pulse and RNEG having a negative pulse in place of every negative AMI pulse. CN8333 Control Signals 59 59 59 ENDECDIS Encoder/decoder disable (for all channels) 0 = NRZ format. Transmit data pins TPOS and TNEG are interpreted as TNRZ and NC (not connected). Receive data pins RPOS and RNEG are interpreted as RNRZ and RLCV. In this mode, all line code violations are reported as active high on RLCV. — 61 61 TAIS1 Transmit Ch1 AIS mode enable I Transmission of Alarm Indication Signal (AIS) for a given channel. Replace transmit data with AIS signal. The AMI form of AIS supported is alternating 1s. (+1, -1, +1, -1, +1, ...) Looping takes precedence over AIS. 1 = AIS mode enabled 0 = AIS mode disabled 51 — 51 TAIS/ TAIS2 Transmit Ch2 AIS mode enable I 40 40 40 TAIS2/ TAIS3 Transmit Ch3 AIS mode enable I 43 43 43 E3MODE E3MODE I When the pin is set to high, it enables the E3 mode on all channels, instead of the DS3/STS-1 mode. This also changes the pulse shaper to E3 mode and overrides all LBO pins. It also changes the encoder/decoder from B3ZS mode to HDB3 mode. 1 = E3 mode 0 = DS3/STS-1 mode 44 72 72 LBO/ LBO1 Transmit line Ch1 build-out mode I — 29 44 LBO2 Transmit line Ch2 build-out mode I Line build-out mode per channel, based on the length of cable on the transmit side of the cross-connect block. This bit is overridden and the pulse shaper is disabled (no pulse shaping) if E3MODE = 1. — — 29 LBO3 Transmit line Ch3 build-out mode I 1 = Inserts line build-out into the transmit channel. Usually used when the transmit cable is less than 350 feet in length. 0 = Line build-out bypassed (not inserted). Usually used when the transmit cable is greater than 350 feet in length. 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential 1-7 1.0 Pin Description CN8331/CN8332/CN8333 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 1.1 Pin Assignments Table 1-1. CN8331/CN8332/CN8333 Pin Definitions (4 of 6) Pin # Signal Name Description I/O/P Notes 74 LLOOP/ LLOOP1 Local loopback enable Ch1 I 27 56 LLOOP2 Local loopback enable Ch2 I Local loopback enable per channel. The transmit data is looped back immediately from the encoder to the decoder in place of the received data. — — 27 LLOOP3 Local loopback enable Ch3 I 1 = local loopback enabled 0 = local loopback disabled 57 75 75 RLOOP/ RLOOP1 Remote loopback enable Ch1 I — 26 57 RLOOP2 Remote loopback enable Ch2 I Remote loopback enable per channel. The receive data, retimed after clock recovery, is looped back into the AMI generator in place of the transmit data. — — 26 RLOOP3 Remote loopback enable Ch3 I 1 = remote loopback enabled 0 = remote loopback disabled 45 71 71 XOE/ XOE1 Transmit output enable Ch1 I Transmit output enable per channel. — 30 45 XOE2 Transmit output enable Ch2 I — — 30 XOE3 Transmit output enable Ch3 I — 70 70 REQH1 Ch1 Receive High EQ Gain Enable I 46 — 46 REQH/ REQH2 Ch2 Receive High EQ Gain Enable I — 31 31 REQH3 Ch3 Receive High EQ Gain Enable I CN8331 CN8332 CN8333 56 74 — 1 = transmit line output driver enabled 0 = transmit output driver set to high impedance state The equalizer in the CN833x has two gain settings. The higher gain setting is designed to optimally equalize a nominally-shaped (meets the pulse template), pulse-driven DS3 or STS-1 waveform that is driven through 0–900 feet of cable. Square-shaped pulses such as E3 or DS3-HIGH require less high-frequency gain and should use the low EQ gain setting. REQH = 1 high EQ gain (DS3/STS-1 modes) REQH = 0 low EQ gain (E3/DS3 Square Modes) Power/Ground 1-8 12 4 4 TVDD/ TVDD1 TX power Ch1 P — 20 12 TVDD2 TX power Ch2 P — — 20 TVDD3 TX power Ch3 P 9 1 1 TVSS/ TVSS1 TX ground Ch1 P — 17 9 TVSS2 TX ground Ch2 P — — 17 TVSS3 TX ground Ch3 P 13 5 5 RVDD/ RVDD1 RX power Ch1 P — 13 13 RVDD2 RX power Ch2 P — — 21 RVDD3 RX power Ch3 P Power pins for transmit circuitry per channel (3.3 V). Ground pins for transmit circuitry per channel. Power pins for receive circuitry per channel (3.3 V). Connect to 3.3 V power. Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B CN8331/CN8332/CN8333 1.0 Pin Description Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 1.1 Pin Assignments Table 1-1. CN8331/CN8332/CN8333 Pin Definitions (5 of 6) Pin # Signal Name Description I/O/P 8 RVSS RVSS1 RX ground Ch1 P 24 16 RVSS2 RX ground Ch2 P — — 24 RVSS3 RX ground Ch3 P Connect to ground. 60 60 60 DVDDC Digital core power P Digital core power for all channels (3.3 V). 41 41 41 DVSSC Digital core ground P Digital core ground for all channels. 79 79 79 VGG 5 V/3.3 V ESD pin (1) P 5 V supply for 5 V-tolerant, digital pad ESD diodes. No static power is drawn from pin. 73 73 73 DVDDIO Digital I/O power P Connect to 3.3 V digital power. 28 28 28 DVSSIO Digital ground P Digital ground. 4, 5, 20, 21 12, 13 — VDD Power P Connect to 3.3 V power. 1, 8, 17, 24 9, 16 — VSS Ground P Connect to ground. Power down transceiver channel 0 = Power down channel (off) 1 = Channel active (on) CN8331 CN8332 CN8333 16 8 — Notes Ground pins for receive circuitry per channel. Miscellaneous 58 76 76 PD/ PD1 Power down for Ch1 I — 25 58 PD2 Power down for Ch2 I — — 25 PD3 Power down for Ch3 I Note: A special power-down mode exists when all three PDBs are set low. This special mode shuts off the entire chip (including biasing). This is useful for static Idd testing. (See PD pin). 47 65 65 REFCLK/ REFCLK1 Reference clock for Ch1 I Reference clock from off-chip. — 36 47 REFCLK2 Reference clock for Ch2 I — — 36 REFCLK3 Reference clock for Ch3 I 80 80 80 RBIAS Bias resistor O A 12.1 kΩ ±1% resistor tied from this pin to ground provides the current reference to the entire chip.(2) 78 78 78 Reset Reset I/O Asynchronous reset (reset entire device). 77 77 77 GPD Global Power Down I/O Power Down (device enter low power state for Static Idd testing). 100604B This clock should be set to one of the following: • E3 rate (34.368 MHz) • DS3 rate (44.736 MHz) • STS-1 rate (51.84 MHz) The clock rate should correspond to the mode of operation that has been chosen for the channel. Conexant Preliminary Information/Conexant Proprietary and Confidential 1-9 1.0 Pin Description CN8331/CN8332/CN8333 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 1.1 Pin Assignments Table 1-1. CN8331/CN8332/CN8333 Pin Definitions (6 of 6) Pin # CN8331 CN8332 2, 3, 6, 7, 10, 11, 18, 19, 14, 15, 22, 23, 42, 44, 25, 26, 45, 47, 27, 29, 48, 49, 30, 31, 50, 51, 32, 33, 52, 53, 34, 35, 54, 55, 36, 37, 56, 57, 58 38, 39, 40, 42, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 74, 75, 76 Signal Name Description I/O/P NC No connect — Notes CN8333 — Not connected. NOTE(S): (1) This pin should be connected to 3.3 V in an all-3.3 V design. Placing a capacitor from this pin to ground may result in instabilities. 3. All digital input pins contain a 75 KΩ pull-down resistor from input to DVSS. (2) 1-10 Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B 2 2.0 Functional Description 2.1 Overview CN8333 is a triple E3/DS3/STS-1 Line Interface Unit (LIU). It is the physical layer interface between the data framer (or other terminal-side equipment) and the electrical cable used for data transmission. The CN8333 LIU consists of three independent data transceivers that can operate over type 734/728 coaxial cable at the rates of 34.368 Mbps (E3), 44.736 Mbps (DS3), and 51.84 Mbps (STS-1). The transmit side takes an NRZ or already-encoded dual rail input and encodes it into AMI B3ZS (for DS3/STS-1) or HDB3 (for E3) analog waveforms to be transmitted over the coaxial cable. The receiver side takes in the attenuated and distorted analog receive signal and equalizes, slices, and resynchronizes the signal before decoding it to the NRZ output or sending out a non-decoded dual rail. CN8331 and CN8332 are single- and dual-E3/DS3/STS-1 LIUs, respectively. In all respects, their performance and features are identical to the CN8333. The architecture of the CN833x includes the following internal functions for each channel: General: • • • bias generator power-on reset loopback MUXes Transmitter: • • • • B3ZS/HDB3 encoder Alarm Indication Signal (AIS) insertion pulse shaper line driver Receiver: • • • • • 100604B Automatic Gain Control receive equalizer Clock Recovery Circuit Loss Of Signal (LOS) detector B3ZS/HDB3 decoder with bipolar violation detector Conexant Preliminary Information/Conexant Proprietary and Confidential 2-1 2.0 Functional Description CN8331/CN8332/CN8333 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.1 Overview In addition, each channel has the ability to perform remote and local loopbacks. Figure 2-1 illustrates a typical application using the CN833x in a channel. External pins are provided to configure the various line rates and formats for each channel. The CN833x is used as a data transceiver over a coaxial cable that is up to 900 feet long (or up to 450 feet from the DSX) in an on-premise environment within any public or private networks which use these data rates. Figure 2-1. Typical Application Of Single CN833x Channel TX RX 0–450 ft COAX (type 734/728) 0–450 ft COAX (type 734/728) 0–450 ft COAX (type 734/728) DSX DSX 0–450 ft COAX (type 734/728) RX TX 100604_012 2-2 Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B 2.0 Functional Description CN8331/CN8332/CN8333 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.2 Transmitter 2.2.2 Pulse Shaper The pulse shaper converts the two digital (clocked) positive and negative pulses into a single analog three-level Alternate Mark Inversion (AMI) pulse. The pulses are in Return to Zero (RZ) format, meaning that all positive and negative pulses have a duration of the first half of the symbol period. For the E3 rate (E3MODE = 1), the AMI pulse is a full-amplitude, square-shaped pulse with very little slope. Figure 2-2. Pulse Shaper E3 Mode + Pulse – Pulse LBO LBO = 0 Pulse Shaper Line Driver LBO = 1 100604_008 For DS3/STS-1 rates, a pulse-shaper block is used to shape the transmit waveform and reduce its high-frequency energy content. This ensures that the transmit pulse template is met at the cross-connect block, which follows 0–450 feet of transmit-side coaxial cable. 2-4 Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B CN8331/CN8332/CN8333 2.0 Functional Description Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.2 Transmitter 2.2.3 Line Driver The differential line driver takes the filtered transmit waveform, increases it to the proper level, and drives it into the transmit magnetics. The two external discrete back-matching resistors (36 Ωs) aid in line matching. The driver is presented with an approximately 150 Ω differential load. Driver gain accounts for the 6 dB gain loss in the back-matching resistors. Figure 2-3 illustrates the Pulse/Power template measurement points for the various data rates. Figure 2-3. Pulse Measurement Points Pulse/Power Template for DS3/STS-1 TX 0–450 ft COAX (type 734/728) 0–450 ft COAX (type 734/728) DSX RX Pulse/Power Template for E3 RX 0–450 ft COAX (type 734/728) DSX 0–450 ft COAX (type 734/728) TX 100604_013 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential 2-5 2.0 Functional Description CN8331/CN8332/CN8333 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.2 Transmitter 2.2.4 Transmit Pulse Mask Templates and Power Measurements Figure 2-4. Transmit Pulse Mask for E3 Rate Transmit Pulse Mask for E3 1.2 1 Normalized Pulse Amplitude 0.8 0.6 0.4 0.2 0 0.2 0.5 0.33 0.167 0 0.167 0.33 0.5 Normalized Symbol Time 8333_007 2-6 Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B CN8331/CN8332/CN8333 2.0 Functional Description Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.2 Transmitter Figure 2-5. Transmit Pulse Mask for DS3 and STS-1 Rates Transmit Pulse Mask for DS3 Rates 1.2 1 Normalized Pulse Amplitude 0.8 0.6 0.4 0.2 0 0.2 1 0.5 0 0.5 Normalized Symbol Time 1 1.5 1 1.5 Transmit Pulse Mask for STS-1 Rates 1.2 1 Normalized Pulse Amplitude 0.8 0.6 0.4 0.2 0 0.2 1 0.5 0 0.5 Normalized Symbol Time 8333_008 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential 2-7 CN8331/CN8332/CN8333 2.0 Functional Description Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.3 Receiver 2.3 Receiver This section describes in detail various blocks in the CN8331/CN8332/CN8333 receiver. 2.3.1 Receive Sensitivity The receiver recovers data from the coaxial cable that is attenuated due to the frequency-dependent characteristics of the cable. In addition, the receiver compensates for the flat loss (across all frequencies) in the various electrical components and the variation in transmitted signal power. The CN833x device is able to recover data that has been attenuated by a maximum of 900 feet of coax having characteristics and attenuation consistent with ANSI T1.102-1993, Annex C, Figure C.2. This approximates the characteristics of AT&T type 734/728 cable; almost the same attenuation characteristic is achieved by one-half the length of AT&T type 735 cable. 2.3.2 AGC/VGA Block The Variable Gain Amplifier (VGA) receives the AMI input signal from the coaxial cable. The VGA supplies flat gain (independent of frequency) to make up for various flat losses in the transmission channel and for loss at one-half the symbol rate that cannot be made up by the equalizer. The VGA gain is controlled by a feedback loop which senses the amplitude of the equalizer output, acting to servo this amplitude for optimal slicing. 2.3.3 Receive Equalizer The receive equalizer receives the differential signal from a VGA and acts to boost the high frequency content of the signal to reduce inter-symbol interference (ISI) to the point that correct decisions can be made by the slicer with a minimum of jitter in the recovered data. The REQH pin is provided to allow lower amounts of equalization (shorter equivalent cable lengths) for cases where a square-shaped pulse (that does not meet the DS3/STS-1 standards) is transmitted to the receiver. A square-shaped input has a much larger high-frequency content and could have overshoots at the EQ output high enough to cause bit errors. Setting REQH = 0 will lower the gain and reduce the amount of overshoot. 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential 2-9 2.0 Functional Description CN8331/CN8332/CN8333 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.3 Receiver 2.3.4 The PLL Clock Recovery Circuit The clock recovery circuit (RX PLL) extracts the embedded clock from the sliced data and provides this clock and the retimed data to the decoder (data mode). Upon startup (after the internal reset is deasserted), the RX PLL uses a reference clock (REFCLK, running at the symbol rate) and a phase-frequency detector to lock to the correct data rate (reference mode). During reference mode, the data outputs are squelched (set to 0). The RX PLL is kept in reference mode until a valid input is detected. 2.3.5 Loss Of Signal (LOS) Detector The Receive Loss Of Signal (RLOS) is a digital function which monitors the retimed data from the clock recovery block. The AMI data is checked for a continuous run of zeroes. When a continuous run of 128 ± 1 consecutive zeroes occurs, the RLOS signal is asserted. After the RLOS signal is asserted, a 1s count is made on every block of 128 AMI symbols. The RLOS signal is deasserted when the 1s count within a block of 128 symbols is at least: B3ZS: Minimum 1s density = 39 ± 1 count out of 128 (~30.5%) HDB3: Minimum 1s density = 29 ± 1 count out of 128 (~22.7%) The RLOS detector will always monitor the cable-side RX inputs. The detector is not affected by the state of remote or local looping. 2.3.6 Jitter Tolerance The CN833x receiver is able to tolerate a specified amount of high-frequency jitter in the received signal while providing error-free operation (generally defined as a bit error rate of less than 10-9). The specifications (illustrated in Figure 2-7) for jitter tolerance are discussed in the following documents: • NOTE: 2-10 E3 rate – ITU-T G.823 and ETSI TBR24 contain frequency masks for input jitter tolerance. To meet jitter transfer requirements for loop-timed operation, an external jitter attenuator is required. The jitter attenuator lessens jitter from the receive clock. • DS3 rate – ITU-T G.823 and Bellcore GR499 specify jitter tolerance frequency masks for Category I and Category II interfaces. • STS-1 rate – Bellcore GR253 specifies a jitter tolerance. It is noted that the STS-1 jitter tolerance differs from DS3 requirements only for Category II interfaces. Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B CN8331/CN8332/CN8333 2.0 Functional Description Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.3 Receiver Figure 2-7. Minimum Input Jitter Tolerance Requirement E3 Rate Input Jitter Amplitude 1.0 UI 0.1 UI 100 Hz 1 kHz 10 kHz 100 kHz 1 MHz Jitter Frequency DS3 / STS-1 Rates STS-1 DS3 Category I DS3 Category II Input Jitter Amplitude 10 UI 1.0 UI 0.1 UI 10 Hz 100 Hz 1 kHz 10 kHz 100 kHz Jitter Frequency 100604_014 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential 2-11 2.0 Functional Description CN8331/CN8332/CN8333 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.3 Receiver 2.3.7 B3ZS/HDB3 Decoder With Bipolar Violation Detector In the CN833x device, when ENDECDIS = 0 (encoder/decoder enabled), the decoder takes the output from the clock recovery circuit and decodes the data (HDB3 or B3ZS) into a single retimed NRZ data signal. The data signal is then sent out of the CN833x over the RNRZ (RPOS) pin. Any detected Line Code Violations (LCV) are sent out over the corresponding RLCV (RNEG) pin. The RLCV pin is asserted for one symbol period at the time the violation appears on the RX output pin (RNRZ). The following shows data sequence criteria for LCV; violations are indicated in bold text. A valid bipolar pulse is indicated by a B. A bipolar violation (non-alternating positive or negative) pulse is indicated by a V. • • • Excessive zeros: 0, 0, 0, 0 (HDB3) or 0, 0, 0 (B3ZS). These violations are passed on as 0 data on the RNRZ pin. Bipolar violation: B, 0, V (i.e., +1, 0, +1 or -1, 0, -1 for HDB3) B, V (B3ZS and HDB3). These violations are passed on as 1 data on the RNRZ pin. Coding violation: 0, 0, V (HDB3) or 0, V (B3ZS) with an even number of Bs since the last valid 0 substitution V (follows coding rule). These violations are passed on as 0 data on the RNRZ pin. The even/odd counter (used to count the number of Bs between Vs) will count a bipolar violation as a B. A coding violation or a valid 0 substitution resets the counter. When ENDECDIS = 1, the decoder is disabled, and the retimed slicer outputs are sent out over RPOS (RNRZ) and RNEG (RLCV) pins. These outputs are then decoded by the CN8340/CN8330 or other downstream device. Line code violations are not detected in this mode of operation. The decoder is configurable for either: • • E3 mode using HDB3 coding (E3MODE = 1) DS3/STS-1 mode using B3ZS coding (E3MODE = 0) The receiver digital data outputs are centered on the rising edge of RCLK (see Section 2.8). 2.3.8 Data Squelching A counter in the receiver keeps track of the number of consecutive symbol periods without a valid data pulse. When 128 or more 0s in a row are counted, the receiver assumes that it has lost the signal and resets itself to try and regain the signal. While the receiver is reacquiring the signal, the clock recovery block locks to the reference clock and the data squelching is achieved by forcing the data bits to zero. The data squelching is true in both NRZ and dual rail mode. When the input signal has been properly amplified and equalized, the clock recovery PLL will then switch to the incoming data. 2-12 Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B CN8331/CN8332/CN8333 2.0 Functional Description Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.4 Additional CN8331/CN8332/CN8333 Functions 2.4 Additional CN8331/CN8332/CN8333 Functions 2.4.1 Bias Generator To achieve good isolation between the channels, each channel utilizes an independent power and ground to both transmit and receive. Additionally, each channel has its own band gap voltage reference. Because only one external resistor for current generation exists, only one band gap voltage can be used. The band gap from Ch1 has been chosen for this task. The 12.1 kΩ external resistor from pin RBIAS to ground, is specified to have a tolerance of ±1%. This helps to keep tighter control on power dissipation and circuit performance. NOTE: Capacitance should be kept to a minimum on the RBIAS pin. 2.4.2 Power-On Reset (POR) A POR function is provided in the CN833x device to ensure all of the resettable digital logic and analog control lines are starting from a known state. This circuit uses a fixed RC timer (~1µs); additionally, 128 clocks from REFCLK are counted (after the RC timer has timed-out) before reset is deasserted, which begins timing after a minimum supply voltage is reached (see Table 2-2). 2.4.3 Loopback Multiplexers (MUXes) Two loopback MUXes per channel in the CN833x allow for local loopback (terminal or framer side), remote loopback (cable side), or both (the AIS signal follows the same path as the transmit data during loopback). The RLOS signal monitors the RX cable inputs irrespective of any loopback. In remote loopback, set by asserting pin RLOOP high, the receive data (retimed after clock recovery but not decoded) loops back into the pulse shaper in place of the transmit data. Additionally, this data sent out the RPOS, RNEG, and RCLK pins. In local loopback, set by asserting pin LLOOP, the transmit data loops back immediately from the encoder output to the decoder input in place of the received data. Additionally, this data is sent out the TLINEP and TLINEM pins. 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential 2-13 2.0 Functional Description CN8331/CN8332/CN8333 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.5 Mechanical Specifications 2.5 Mechanical Specifications Figure 2-8. Mechanical Drawing—Dimensions D D1 Pin #1 Ref. Mark D2 D 3 D D D1 D2 1 e D3 b TOP BOTTOM Millimeters Dim. See DETAIL B A A A1 2 c L DETAIL B L1 Min. A A1 Max. 1.20 MAX. 0.05 0.15 0.95 1.05 15.75 16.25 A2 D D1 D2 13.90 D3 L L1 b c e Coplanarity 14.10 Inches Min. Max. 0.047 MAX. 0.002 0.006 0.040 0.041 0.620 0.547 0.640 0.555 12.35 REF. 6.50 REF. 0.45 0.75 0.486 REF. 0.256 REF. 0.018 0.030 1.00 REF. 0.32 REF. 0.09 0.20 0.039 REF. 0.026 REF. 0.013 REF. 0.004 0.008 0.65 REF. 0.10 MAX. 0.004 MAX. Ref. 80-Pin ETQFP (GP00-D537) 100604_015 2-14 Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B CN8331/CN8332/CN8333 2.0 Functional Description Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.6 Electrical Characteristics 2.6 Electrical Characteristics 2.6.1 Absolute Maximum Ratings Table 2-1. Absolute Maximum Ratings Symbol Parameter Min Max Unit DVDDC RVDD TVDD VDD Power Supply Voltage –0.3 6 V VI Voltage on Any Signal Pin –1.0 VGG + 0.3 V V TST Storage Temperature –40 125 °C TVSOL Vapor Phase Soldering Temperature (1 min.) — 220 °C θJA Thermal Resistance (Still air, socketed) — 40 °C θJA Thermal Resistance (Still air, soldered) — 24 °C θJc — — 7.40 °C FIT Failures in time @ 89,000 device hours, temperature of 55 °C, 0 failures. — 313 fits /W /W /W NOTE(S): 1. Stresses above those listed as absolute maximum ratings may cause permanent damage to the device. This is a stress rating only, and functional operation of the device at these or any other conditions beyond those indicated in the other sections of this document is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential 2-15 CN8331/CN8332/CN8333 2.0 Functional Description Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.7 DC Characteristics 2.7 DC Characteristics Table 2-3. DC Characteristics Parameter Conditions Min Nom Max Unit Vih high threshold Digital inputs 2.0 — VGG + 0.3 V Vil low threshold Digital inputs –0.3 — 0.8 V Voh high threshold Digital outputs, Ioh = –4 mA 2.4 — — V Vol low threshold Digital outputs, Iol = 4 mA — — 0.4 V ILEAK 0 V ≤ digital Vin ≤ VGG –10 — 200 µA — — 10 pF — — 15 pF Input capacitance Load capacitance — Digital outputs NOTE(S): 1. The digital inputs of CN833x are TTL 5 V compliant. These inputs are diode protected to DVDDIO and DVSSIO pins. Additionally, all of the CN8331/CN8332/CN8333 digital inputs contain 75 kΩ pull-down resistors. 2. The digital outputs of CN8331/CN8332/CN8333 are also TTL 5 V compliant. However, these outputs will not drive to 5 V, nor will they accept 5 V external pullups. The output is DVDDC (3.3 V). 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential 2-17 CN8331/CN8332/CN8333 2.0 Functional Description Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 2.8 AC Characteristics Figure 2-9. Timing Diagram Tosym DATA OUTPUTS RCLK Towidth Todelay RPOS/RNRZ, RNEG/RLCV Tisym DATA INPUTS Tiwidth TCLK Tisetup TPOS/TNRZ, TNEG, TAIS, Don't Care Tihold Valid Data Don't Care 100604_016 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential 2-19 2.0 Functional Description 2.8 AC Characteristics 2-20 CN8331/CN8332/CN8333 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B 3 3.0 Applications The CN8331/CN8332/CN8333 can be used in a variety of applications. Figure 3-1 illustrates an example of three DS3 lines being terminated by the CN8333. The data and clock are extracted and passed on to the framer chip for further data manipulation and user interface. It is important to employ high-frequency design techniques for the printed board layout. 3.1 PCB Design Considerations for CN8331/CN8332/CN8333 The CN8333 device is a triple LIU operating at frequencies up to 52 MHz. The high-speed nature of the device calls for a careful design of the PCB using this part. Some design considerations are outlined below. 3.1.1 Power Supply and Ground Plane A unified power plane with properly placed capacitors of the correct size will mitigate most power rail-related voltage transients. A properly placed bulk capacitor, where the power enters the board, with noise-bypassing capacitors at the power pins on the integrated circuits should be adequate. The noise-bypassing capacitors must be able to supply all the switching current. Ferrite beads are used with power rails to filter the high-frequency noise. For every design, noise frequencies and levels are different. Therefore, whether beads are necessary, and the effective frequency where they should operate, is difficult to determine. It is a good idea to provision for ferrite beads on the boards. The board trace from the CN8333 power supply pin to the noise-bypassing capacitor should be minimized. Additionally, ground connections from the ground plane to the CN8333 ground pins and the noise-bypassing capacitor ground pins should be minimized. A unified ground plane is the best way to minimize ground impedance. Most of the ground noise is produced by the return currents and power supply transients during switching. This effect is minimized by reducing the ground plane impedance. 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential 3-1 3.0 Applications CN8331/CN8332/CN8333 3.1 PCB Design Considerations for CN8331/CN8332/CN8333 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 3.1.2 Impedance Matching It is critical that traces around the transformers and matching resistors be kept to a minimum length and, in the following cases, the trace impedance be matched to 75 Ω: • • The impedance from the BNC connector to the transformer The impedance from the transformer to the matching resistors 3.1.3 Other Passive Parts The reference design uses the Pulse T3001 extended temperature range 1:1 transformer for the coupling of the BNC connector to the device. The ferrite beads used to decouple the receive- and transmit-VDD pins and the ferrite beads on all analog input VDD pins are type 2508056017Y0 from Fair-Rite. The bulk capacitor used for where the power enters the board can be a electrolytic or tantulum type capacitor, the recommended value and type is a 220µf tantulum capacitor. 3.1.4 IBIS Models IBIS (Input/Output Buffer Interface Specification) models for the CN8331/CN8332/CN8333 are available from Conexant. 3.1.5 Recommended Vendors Part # T3001, Data Sheet - T619 America Address: Telo: Fax: Northern Asia Telo: Northern Europe Telo: Fax: 3-2 Pulse Corporate Office 12220 World Trade Drive San Diego, CA 92128 858-674-8100 858-674-8262 Telo: Fair-Rite Products Corp. P.O. Box J One Commercial Row Wallkill, NY 12589 914-895-2055 Pulse 3F-4, No. 81, Sec. 1 Hsin Tai Wu Road Hsi-Chih Tapei Hsien, Taiwan R.O.C. 886-2-26980228 886-2-26980948 Pulse 1S2 Huxley Road The Surrey Research Park Guildford, Surrey GU2 5RE United Kingdom 44-1483-401700 44-1483-401701 Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B CN8331/CN8332/CN8333 3.0 Applications Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit 3.1 PCB Design Considerations for CN8331/CN8332/CN8333 Figure 3-1. Typical Connection of CN8333 CN8333 TPOS TNEG TCLK Framer TLINEP TX TLINEM 31.6 W Channel 1 RPOS RNEG RCLK 37.4 W RLINEP RX Type 728, 734, 735 75 W 31.6 W 1:1 0.01µF 1:1 Type 728, 734, 735 75 W RLINEM 37.4 W MODE RESET TX TLINEM 31.6 W Channel 2 RPOS RNEG RCLK 37.4 W RLINEP RX Type 728, 734, 735 75 W 31.6 W 1:1 TLINEP TPOS TNEG TCLK Framer BIAS 0.01µF 1:1 Type 728, 734, 735 75 W RLINEM 37.4 W MODE RESET TX TLINEM 31.6 W Channel 2 RPOS RNEG RCLK 37.4 W RLINEP RX Type 728, 734, 735 75 W 31.6 W 1:1 TLINEP TPOS TNEG TCLK Framer BIAS 0.01µF 1:1 Type 728, 734, 735 75 W RLINEM 37.4 W MODE BIAS RESET MODE BIAS RESET 12.1K W RBIAS Mode/Status Pins NOTE(S): All transformers are part number T3001 from Pulse Technology. (See Recommended Vendors, page 3.2.) 100604_004 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential 3-3 3.0 Applications CN8331/CN8332/CN8333 3.1 PCB Design Considerations for CN8331/CN8332/CN8333 3-4 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B A Appendix A A.1 Applicable Standards The applicable standards documents are as follows: • ANSI T1.102-1993 (DS3 and STS-1 standard) • ANSI T1.404a-1996 (DS3 metallic interface) • ITU Recommendation G.703 (DS3 and E3 standard) • ITU Recommendation G.823 and G.824 (jitter and wander) • Bellcore GR499, Issue 1, 12/89 (formerly TR-TSY-000499) (DS3 and STS-1 requirements) • Bellcore GR253, Issue 2, 12/91 (formerly TA-NWT-000253) (STS-1 requirements and jitter) • Bellcore TR-TSY-000191, Issue 1, 5/86 (AIS and LOS) • ETSI TBR24 and TBR25 (E3 terminal equipment interface) • ETSI ETS 300 686 and ETS 300 687 (E3 standard) • AT&T Technical Reference TR54014, May 1992 (Accunet Interface Specification for DS-3 jitter only) 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential A-1 CN8331/CN8332/CN8333 Appendix A A.1 Applicable Standards A-2 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit Conexant Preliminary Information/Conexant Proprietary and Confidential 100604B B Appendix B B.1 Evaluation Module Schematic 100604B Conexant Preliminary Information/Conexant Proprietary and Confidential B-1 Single/Dual/Triple E3/DS3/STS-1 Line Interface Unit B.1 Evaluation Module Schematic L1 5 6 2 4 1 CHANNEL 1 TRANSMIT 3 R1 31.6 R2 31.6 CC CC +3_3V +3_3V +5V TMUXIO2 TMUXIO1 RLOOP1 PDB1 C11 CC L17 +3_3V +3_3V PDB2 XOE2 LBO2 LLOOP2 RLOOP2 TAIS2/TMUXA3 REQH2/TMUXA0 SW4 4 3 +3_3V 2 Pin DIP Switch Setting Pin 2 E3MODE 1=E3 mode is enabled 0=Disabled Seven Position DIP Switch Settings for all Channels DECODER AND E3 SELECTION Position 1 PDB POWERDOWN (0=Powerdown 1=Active) Position 2 RLOOP (1=Remote LPBK Enabled 0=Disabled) Position 3 LLOOP (1=Local Loop Enabled 0=Disabled) Position 4 LBO (1=TX CABLE less than 250ft 0=greater than 250ft) Position 5 XOE (1=Transmitter Enabled 0=Disabled) Position 6 TAIS (1=Enable AIS operation 0=disable) Position 7 REQH(1=Enable Equalization 0=Disable) +3_3V Preliminary Information/Conexant Proprietary and Confidential PULSE T3001 L2 J7 0.1 LBO3 XOE3 7 LLOOP1 LBO1 RNEG1/RLCV1 REQH1/TMUXDAT XOE1 RPOS1/RNRZ1 PDB1 RLOOP1 PDB3 LLOOP3 RLOOP3 TAIS3/TMUXA4 REQH3/TMUXA1 6 +3_3V 5 CHANNEL 1 RECEIVE L10 2 CC C12 RCLK1 RLOS1 XOE1 LBO1 LLOOP1 TAIS1/TMUXA2 7 BNC BNC CC L11 3 1 0.1 TCLK1 TPOS1/TNRZ1 TNEG1/NC1 REFCLK 6 8 0.01 L7 +3_3V R13 +3_3V 9 R3 C1 CC C4 CC 0.1 L16 REQH1/TMUXDAT C10 CC 2 6 CC C5 CC 0.1 ENDECDIS PDB2 RLOOP2 LLOOP2 5 10 37.4 R4 37.4 CC TAIS1/TMUXA2 56 55 0.1 4 11 1 5 4 R5 31.6 CC LLOOP2 DVDD 60 59 ENDECDIS PDB2 58 RLOOP2 57 RNEG2/RLCV2 TCLK2 TNEG2/NC2 3 12 J1 J2 2 3 L3 PULSE T3001 CHANNEL 2 TRANSMIT 6 12.1K TVSS1 TLINE1P TLINE1M TVDD1 RVDD1 54 RPOS2/RNRZ2 RCLK2 RLOS2 TAIS2/TMUXA3 TPOS2/TNRZ2 1 2 4 8 7 1 +3_3V E3MODE 3 9 6 8 Pin 1 ENDECDIS 1=Dual rail pulse coded data format ENDECDIS 2 10 5 9 1 CC 6 RNEG2/RLCV2 RPOS2/RNRZ2 48 49 50 51 RCLK2 53 RLOS2 52 TAIS2/TMUXA3 TCLK2 TNEG2/NC2 TPOS2/TNRZ2 REFCLK REQH2/TMUXA0 XOE2 LBO2 TMUXLAT 1 11 4 10 R6 1 2 3 4 5 SOCKET CN8333 U1 80EXFP E3MODE SW2 3 11 5 N1 RLINE1P RLINE1M RVSS1 TVSS2 TLINE2P TLINE2M TVDD2 RVDD2 DVSS 41 REQH2/TMUXA0 REQH3/TMUXA1 TAIS1/TMUXA2 TAIS2/TMUXA3 TAIS3/TMUXA4 REQH1/TMUXDAT SW3 12 2 12 4 L12 CC 7 8 9 10 11 12 13 LLOOP3 13 1 13 2 +3_3V C6 0.1 C7 0.1 CC TMUXIO2 77 PDB1 76 RLOOP3 27 14 14 31.6 L13 RLINE2P RLINE2M LBO2 44 E3MODE 43 42 TMUXLAT DIGITAL GND TAIS3/TMUXA4 TCLK3 TNEG3/NC3 TPOS3/TNRZ3 REFCLK RLOS3 RCLK3 RPOS3/RNRZ3 RNEG3/RLCV3 REQH3/TMUXA1 XOE3 LBO3 LLOOP3 RLOOP3 PDB3 SW5 3 PULSE T3001 +3_3V 14 15 TAIS3/TMUXA4 REFCLK2 47 46 REQH2/TMUXA0 XOE2 45 40 RVSS2 TCLK3 16 TPOS3/TNRZ3 39 +3_3V TNEG3/NC3 38 SW9 37 TVSS3 TAIS1/TMUXA2 61 REFCLK3 17 RPOS3/RNRZ3 TLINE3P TLINE3M TVDD3 REFCLK1 65 RLOS3 36 18 19 20 +3_3V RNEG3/RLCV3 33 REFCLK 32 R7 CC CC C8 14 ANALOG GND NC VCC PDB3 26 CC REQH3/TMUXA1 CHANNEL 2 RECEIVE L4 6 L14 0.1 1 1/4 R17 42.2 XOE3 31 SW1 6 0.01 +3_3V L15 C9 CC 0.1 SOCKET Y1 7 GND OUT 8 C13 CC TMUXLAT 3 1 C2 CC +3_3V CH1_LOS CH2_LOS 0.1 RVSS3 25 13 4 5 7 RLOOP1 75 LLOOP1 74 TMUXIO1 14 9 8 37.4 CC CC CC CC 0.01 2 CH3_LOS 2 10 R8 37.4 R9 31.6 R10 C3 CR1 CR2 2 1 11 5 4 6 5 4 31.6 CC CC CC CC 1 CR3 12 2 3 PULSE T3001 L5 L6 PULSE T3001 CHANNEL 3 TRANSMIT 1 2 3 CHANNEL 3 RECEIVE R11 37.4 37.4 R12 R14 402 R15 402 R16 CC 1 30 BNC BNC BNC BNC 6 5 1 2 4 J8 J9 J10 402 LBO3 TNEG1/NC1 64 TPOS1/TNRZ1 63 TCLK1 62 35 RPOS1/RNRZ1 68 67 RCLK1 RLOS1 66 RCLK3 34 73 DVDD2 LBO1 72 DVSS2 29 J3 J4 J5 J6 3 PULSE T3001 RLOS1 RLOS2 RLOS3 RLINE3P XOE1 71 REQH1/TMUXDAT 70 RNEG1/RLCV1 69 28 80 RVDD3 22 VGG 79 78 RLINE3M 24 23 RBIAS 21 100604B Conexant B-2 CN8331/CN8332/CN8333 Appendix B Figure B-1. Recommended Schematic for the CN833x Device 8333_027 0.0 Sales Offices Further Information: [email protected] 1-800-854-8099 (North America) 33-14-906-3980 (International) Web Site www.conexant.com World Headquarters Conexant Systems, Inc. 4311 Jamboree Road, P.O. Box C Newport Beach, CA 92658-8902 Phone: (949) 483-4600 Fax: (949) 483-6375 U.S. Florida/South America Phone: (727) 799-8406 Fax: (727) 799-8306 U.S. Los Angeles Phone: (805) 376-0559 Fax: (805) 376-8180 U.S. Mid-Atlantic Phone: (215) 244-6784 Fax: (215) 244-9292 U.S. North Central Phone: (630) 773-3454 Fax: (630) 773-3907 U.S. Northeast Phone: (978) 692-7660 Fax: (978) 692-8185 U.S. Northwest/Pacific West Phone: (408) 249-9696 Fax: (408) 249-7113 U.S. South Central Phone: (972) 733-0723 Fax: (972) 407-0639 U.S. Southeast Phone: (919) 858-9110 Fax: (919) 858-8669 U.S. Southwest Phone: (949) 483-9119 Fax: (949) 483-9090 APAC Headquarters Conexant Systems Singapore, Pte. 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