Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Features Four fully integrated E1 line interfaces Includes all driver, receiver, equalization, clock recovery, and jitter attenuation functions Ultralow power consumption Robust operation for increased system margin High interference immunity On-chip transmit equalization for improved sensitivity Low-impedance drivers for reduced power consumption Selectable transmit or receive jitter attenuation/ clock smoothing 3-state transmit drivers High-speed, microprocessor interface Automatic transmit monitor function Per-channel powerdown For use in systems that are compliant with ITU-T G.703, G.732, G.735-9, G.775, G.823-4, and I.431 Common transformer for transmit/receive Fine-pitch (25 mil spacing) surface-mount package, 100-pin bumpered quad flat pack -40 C to +85 C operating temperature range Applications SONET/SDH multiplexers Asynchronous multiplexers (M13) Digital access cross connects (DACs) Channel banks Digital radio base stations, remote wireless modules PBX interfaces Description The T7688 is a fully integrated quad line interface containing four transmit and receive channels for use in European (E1/CEPT) applications. The device has many of the same functions as the Lucent Technologies Microelectronics Group T7290A and provides additional flexibility for the system designer. Included is a parallel microprocessor interface that allows the user to define the architecture, initiate loopbacks, and monitor alarms. The interface is compatible with many commercially available microprocessors. The receiver performs clock and data recovery using a fully integrated digital phase-locked loop. This digital implementation prevents false-lock conditions that are common when recovering sparse data patterns with analog phase-locked loops. Equalization circuitry in the receiver guarantees a high level of interference immunity. As an option, the raw sliced data (no retiming) can be output on the receive data pins. Transmit equalization is implemented with lowimpedance output drivers that provide shaped waveforms to the transformer, guaranteeing template conformance. The quad device will interface to line impedances of 75 or 120 for CEPT operation. A selectable jitter attenuator may be placed in the receive signal path for low-bandwidth linesynchronous applications, or it may be placed in the transmit path for multiplexer applications where CEPT signals are demultiplexed from higher rate signals. The jitter attenuator will perform the clock smoothing required on the resulting demultiplexed gapped clock. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Table of Contents Contents Page Features .................................................................... 1 Applications ............................................................... 1 Description ................................................................. 1 Block Diagram ........................................................... 3 Pin Information .......................................................... 4 System Interface Pin Options ................................ 9 Receiver .................................................................. 10 Data Recovery ..................................................... 10 Jitter ..................................................................... 10 Receiver Configuration Modes ............................ 10 Clock/Data Recovery Mode (CDR) ................... 10 Zero Substitution Decoding (CODE) ................. 10 Alternate Logic Mode (ALM) ............................. 10 Alternate Clock Mode (ACM) ............................ 11 Loss Shut Down (LOSSD) ................................ 11 Receiver Alarms .................................................. 11 Analog Loss of Signal (ALOS) Alarm ................ 11 Digital Loss of Signal (DLOS) Alarm ................. 11 Bipolar Violation (BPV) Alarm ........................... 11 CEPT Receiver Specifications ............................. 12 Transmitter .............................................................. 13 Output Pulse Generation ..................................... 13 Jitter ..................................................................... 13 Transmitter Configuration Modes ........................ 14 Zero Substitution Encoding/Decoding (CODE) ........................... 14 All Ones (AIS, Blue Signal) Generator (TBS) ... 14 Transmitter Alarms .............................................. 14 Loss of Transmit Clock (LOTC) Alarm .............. 14 Transmit Driver Monitor (TDM) Alarm ............... 14 CEPT Transmitter Pulse ...................................... 15 Template and Specifications ............................. 15 Jitter Attenuator ....................................................... 16 Data Delay ........................................................... 16 Generated (Intrinsic) Jitter ................................... 16 Jitter Transfer Function ........................................ 16 Jitter Tolerance .................................................... 16 Jitter Attenuator Enable ....................................... 16 Jitter Attenuator Receive Path Enable (JAR) .... 17 Jitter Attenuator Transmit Path Enable (JAT) ... 17 2 Contents Page Loopbacks ............................................................... 17 Full Local Loopback (FLLOOP) ........................... 17 Remote Loopback (RLOOP) ................................ 17 Digital Local Loopback (DLLOOP) ....................... 17 Other Features ........................................................ 18 Powerdown (PWRDN) ......................................... 18 RESET (RESET, SWRESET) ............................... 18 Loss of XCLK Reference Clock (LOXC) .............. 18 In-Circuit Testing and Driver 3-State (ICT) .......... 18 Microprocessor Interface ......................................... 19 Overview .............................................................. 19 Microprocessor Configuration Modes .................. 19 Microprocessor Interface Pinout Definitions ........ 20 Microprocessor Clock (MPCLK) Specifications ... 21 Internal Chip Select Function ............................... 21 Microprocessor Interface Register Architecture ... 21 Alarm Register Overview (0000, 0001) ............. 23 Alarm Mask Register Overview (0010, 0011) ... 23 Global Control Register Overview (0100, 0101) ................................... 24 Channel Configuration Register Overview (0110--1001) .................................. 25 Other Registers ................................................. 25 I/O Timing ............................................................ 26 XCLK Reference Clock ............................................ 31 Power Supply Bypassing ......................................... 31 External Line Interface Circuitry ............................... 32 Absolute Maximum Ratings ..................................... 33 Handling Precautions .............................................. 33 Operating Conditions ............................................... 33 Timing Characteristics ............................................. 34 Outline Diagram ....................................................... 36 100-Pin BQFP ...................................................... 36 Ordering Information ................................................ 37 DS98-231TIC Replaces DS96-172TIC to Incorporate the Following Updates .............................................. 37 Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Block Diagram The T7688 block diagram is shown in Figure 1. For illustration purposes, only one of the four on-chip line interfaces is shown. Pin names that apply to all four channels are followed by the designation [1--4]. ALOS DLOS RTIP[1--4] EQUALIZER SLICERS RRING[1--4] FLLOOP (NO BLUE SIGNAL) JITTER ATTENUATOR* (TRANSMIT OR RECEIVE PATH) CLOCK/DATA RECOVERY* FLLOOP (DURING BLUE SIGNAL) RPD/RDATA[1--4] BPV DECODER* RND/BPV[1--4] RCLK/ALOS[1--4] XCLK XCLK LOTC PULSEWIDTH CONTROLLER TTIP[1--4] PULSE EQUALIZER DRIVERS SYSTEM INTERFACE RLOOP LINE INTERFACE DLLOOP TDM XCLK JITTER ATTENUATOR* (TRANSMIT OR RECEIVE PATH) TCLK[1--4] TPD/TDATA[1--4] TND[1--4] ENCODER* TRING[1--4] A[3:0] AD[7:0] RDY_DTACK BLUE SIGNAL (AIS) INT LOXC MICROPROCESSOR INTERFACE XCLK LOXC BCLK / 16 WR_DS RD_R/W ALE_AS CS MPMUX MPMODE MPCLK 5-3683(C)r.7 * Function can be bypassed by using the microprocessor interface. Figure 1. Block Diagram (Single Channel) Lucent Technologies Inc. 3 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface RND4/BPV4 RRING4 TRING4 GNDD4 VDDD4 GNDA4 RTIP4 1 100 99 98 97 96 95 94 93 92 91 90 89 VDDA4 2 GNDX4 3 VDDX4 GNDS 4 TTIP4 GNDX1 5 GNDX4 TTIP1 GNDX1 TRING1 VDDA1 6 VDDX1 RRING1 7 GNDD1 8 GNDA1 13 12 11 10 9 VDDD1 RTIP1 RND1/BPV1 Pin Information RPD1/RDATA1 14 88 RPD4/RDATA4 R RCLK1/ALOS1 15 R 87 RCLK4/ALOS4 TND1 16 86 TND4 TPD1/TDATA1 17 85 TPD4/TDATA4 T T TCLK1 18 84 TCLK4 WR_DS 19 83 MPCLK 82 A0 MPMUX 20 CHANNEL 1 MPMODE 21 CHANNEL 4 81 A1 80 A2 RD_R/W 22 79 A3 ALE_AS 23 78 GNDC CS 24 77 VDDC MICROPROCESSOR & CONTROL INT 25 RDY_DTACK 26 GNDC 27 76 AD0 75 AD1 VDDC 28 74 AD2 XCLK 29 73 AD3 BCLK 30 72 AD4 LOXC 31 CHANNEL 2 71 AD5 CHANNEL 3 70 AD6 RESET 32 69 AD7 ICT 33 68 TCLK3 TCLK2 34 T T TPD2/TDATA2 35 67 TPD3/TDATA3 66 TND3 TND2 36 RCLK2/ALOS2 37 R 65 RCLK3/ALOS3 R RPD2/RDATA2 38 64 RPD3/RDATA3 RND3/BPV3 VDDD3 GNDD3 GNDA3 RRING3 VDDA3 RTIP3 GNDX3 TRING3 TTIP3 VDDX3 GNDX3 GNDS TTIP2 GNDX2 VDDX2 TRING2 VDDA2 GNDX2 RTIP2 RRING2 GNDA2 GNDD2 VDDD2 RND2/BPV2 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 5-3684(C).ar.4 Figure 2. Pin Diagram 4 Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Pin Information (continued) Table 1. Pin Descriptions Pin Symbol Type* Name/Description 1, 51 GNDS P Ground Reference for Substrate. 2, 6 GNDX1 P Ground Reference for Line Drivers. 46, 50 GNDX2 52, 56 GNDX3 96, 100 GNDX4 3 TTIP1 O 49 TTIP2 Transmit Bipolar Tip. Positive bipolar transmit output data to the analog line interface. 53 TTIP3 99 TTIP4 4 VDDX1 P 48 VDDX2 Power Supply for Line Drivers. The T7688 device requires a 5 V 5% power supply on these pins. 54 VDDX3 98 VDDX4 5 TRING1 O 47 TRING2 Transmit Bipolar Ring. Negative bipolar transmit output data to the analog line interface. 55 TRING3 97 TRING4 7 VDDA1 P 45 VDDA2 Power Supply for Analog Circuitry. The T7688 device requires a 5 V 5% power supply on these pins. 57 VDDA3 95 VDDA4 8 RTIP1 I 44 RTIP2 Receive Bipolar Tip. Positive bipolar receive input data from the analog line interface. 58 RTIP3 94 RTIP4 9 RRING1 I 43 RRING2 Receive Bipolar Ring. Negative bipolar receive input data from the analog line interface. 59 RRING3 93 RRING4 10 GNDA1 P Ground Reference for Analog Circuitry. 42 GNDA2 60 GNDA3 92 GNDA4 * P = power, I = input, O = output, and Iu = input with internal pull-up. Lucent Technologies Inc. 5 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Pin Information (continued) Table 1. Pin Descriptions (continued) Pin Symbol Type* Name/Description 11 GNDD1 P Ground Reference for Digital Circuitry. 41 GNDD2 61 GNDD3 91 GNDD4 12 VDDD1 P 40 VDDD2 Power Supply for Digital Circuitry. The T7688 device requires a 5 V 5% power supply on these pins. 62 VDDD3 90 VDDD4 13 RND1/BPV1 O 39 RND2/BPV2 63 RND3/BPV3 89 RND4/BPV4 Receive Negative Data. When in dual-rail (DUAL = 1: register 5, bit 4) clock recovery mode (CDR = 1: register 5, bit 0), this signal is the receive negative NRZ output data to the terminal equipment. When in data slicing mode (CDR = 0), this signal is the raw sliced negative output data of the front end. Bipolar Violation. When in single-rail (DUAL = 0: register 5, bit 4) clock recovery mode (CDR = 1: register 5, bit 0), and CODE = 1 (register 5, bit 3), this signal is asserted high to indicate the occurrence of a code violation in the receive data stream. If CODE = 0, this signal is asserted to indicate the occurrence of a bipolar violation in the receive data system. 14 RPD1/ RDATA1 O 38 RPD2/ RDATA2 64 RPD3/ RDATA3 Receive Positive Data. When in dual-rail (DUAL = 1: register 5, bit 4) clock recovery mode (CDR = 1: register 5, bit 0), this signal is the receive positive NRZ output data to the terminal equipment. When in data slicing mode (CDR = 0), this signal is the raw sliced positive output data of the front-end. Receive Data. When in single-rail (DUAL = 0: register 5, bit 4) clock recovery mode (CDR = 1: register 5, bit 0), this signal is the receive NRZ output data. 88 RPD4/ RDATA4 15 RCLK1/ ALOS1 O 37 RCLK2/ ALOS2 65 RCLK3/ ALOS3 Receive Clock. In clock recovery mode (CDR = 1: register 5, bit 0), this signal is the receive clock for the terminal equipment. The duty cycle of RCLK is 50% 5%. Analog Loss of Signal. In data slicing mode (CDR = 0: register 5, bit 0), this signal is asserted high to indicate low amplitude receive data at the RTIP/RRING inputs. 87 RCLK4/ ALOS4 16 TND1 I 36 TND2 Transmit Negative Data. Transmit negative NRZ input data from the terminal equipment. 66 TND3 86 TND4 * P = power, I = input, O = output, and Iu = input with internal pull-up. 6 Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Pin Information (continued) Table 1. Pin Descriptions (continued) Pin Symbol Type* Name/Description 17 TPD1/ TDATA1 I 35 TPD2/ TDATA2 67 TPD3/ TDATA3 Transmit Positive Data. When in dual-rail mode (DUAL = 1: register 5, bit 4), this signal is the transmit positive NRZ input data from the terminal equipment. Transmit Data. When in single-rail mode (DUAL = 0: register 5, bit 4), this signal is the transmit NRZ input data from the terminal equipment. 85 TPD4/ TDATA4 18 TCLK1 I 34 TCLK2 Transmit Clock. CEPT (2.048 MHz 50 ppm) clock signal from the terminal equipment. 68 TCLK3 84 TCLK4 19 WR_DS I Write (Active-Low). If MPMODE = 1 (pin 21), this pin is asserted low by the microprocessor to initiate a write cycle. Data Strobe (Active-Low). If MPMODE = 0 (pin 21), this pin becomes the data strobe for the microprocessor. When R/W = 0 (write), a low applied to this pin latches the signal on the data bus into internal registers. 20 MPMUX I Microprocessor Multiplex Mode. Setting MPMUX = 1 allows the microprocessor interface to accept multiplexed address and data signals. Setting MPMUX = 0 allows the microprocessor interface to accept demultiplexed (separate) address and data signals. 21 MPMODE I Microprocessor Mode. When MPMODE = 1, the device uses the address latch enable type microprocessor read/write protocol with separate read and write controls. Setting MPMODE = 0 allows the device to use the address strobe type microprocessor read/write protocol with a separate data strobe and a combined read/write control. 22 RD_R/W I Read (Active-Low). If MPMODE = 1 (pin 21), this pin is asserted low by the microprocessor to initiate a read cycle. Read/Write. If MPMODE = 0 (pin 21), this pin is asserted high by the microprocessor to indicate a read cycle or asserted low to indicate a write cycle. 23 ALE_AS I Address Latch Enable. If MPMODE = 1 (pin 21), this pin becomes the address latch enable for the microprocessor. When this pin transitions from high to low, the address bus inputs are latched into the internal registers. Address Strobe (Active-Low). If MPMODE = 0 (pin 21), this pin becomes the address strobe for the microprocessor. When this pin transitions from high to low, the address bus inputs are latched into the internal registers. 24 CS Iu Chip Select (Active-Low). This pin is asserted low by the microprocessor to enable the microprocessor interface. If MPMUX = 1 (pin 20), CS can be externally tied low to use the internal chip selection function (see the Internal Chip Select Function section). An internal 100 k pull-up is on this pin. * P = power, I = input, O = output, and Iu = input with internal pull-up. Lucent Technologies Inc. 7 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Pin Information (continued) Table 1. Pin Descriptions (continued) Pin Symbol Type* Name/Description 25 INT O Interrupt. This pin is asserted high to indicate an interrupt produced by an alarm condition in register 0 or 1. The activation of this pin can be masked by microprocessor registers 2, 3, and 4. 26 RDY_DTACK O Ready. If MPMODE = 1 (pin 21), this pin is asserted high to indicate the device has completed a read or write operation. This pin is in a 3-state condition when CS (pin 24) is high. Data Transfer Acknowledge (Active-Low). If MPMODE = 0 (pin 21), this pin is asserted low to indicate the device has completed a read or write operation. 27, 78 GNDC P Ground Reference for Microprocessor Interface and Control Circuitry. 28, 77 VDDC P Power Supply for Microprocessor Interface and Control Circuitry. The T7688 device requires a 5 V 5% power supply on these pins. 29 XCLK Iu Reference Clock. A valid reference clock (32.768 MHz 100 ppm for CEPT operation) must be provided at this input for certain applications (see the XCLK Reference Clock section). XCLK must be an independent, continuously active, ungapped, and unjittered clock to guarantee device performance specifications. An internal 100 k pull-up is on this pin. 30 BCLK Iu Blue Clock. Input clock signal used to transmit the blue signal (all 1s data pattern). In CEPT mode, this clock is 2.048 MHz 50 ppm. An internal 100 k pull-up is on this pin. 31 LOXC O Loss of XCLK. This pin is asserted high when the XCLK signal (pin 29) is not present. 32 RESET Iu Hardware Reset (Active-Low). If RESET is forced low, all internal states in the line interface paths are reset and data flow through each channel will be momentarily disrupted (see the RESET (RESET, SWRESET) section). The RESET pin must be held low for a minimum of 10 s. An internal 50 k pullup is on this pin. 33 ICT Iu In-Circuit Test Control (Active-Low). If ICT is forced low, certain output pins are placed in a high-impedance state (see the In-Circuit Testing and Driver 3-state (ICT) section). An internal 50 k pull-up is on this pin. 69 AD7 I/O 70 AD6 71 AD5 72 AD4 73 AD3 74 AD2 75 AD1 76 AD0 Microprocessor Interface Address/Data Bus. If MPMUX = 0 (pin 20), these pins become the bidirectional, 3-statable data bus. If MPMUX = 1, these pins become the multiplexed address/data bus. In this mode, only the lower 4 bits (AD[3:0]) are used for the internal register addresses. * P = power, I = input, O = output, and Iu = input with internal pull-up. 8 Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Pin Information (continued) Table 1. Pin Descriptions (continued) Pin Symbol Type* Name/Description 79 A3 I 80 A2 81 A1 82 A0 Microprocessor Interface Address. If MPMUX = 0 (pin 20), these pins become the address bus for the microprocessor interface registers. If MPMUX = 1, A3 (pin 79) can be externally tied high to use the internal chip selection function (see the Internal Chip Select Function section). If this function is not used, A[3:0] must be externally tied low. 83 MPCLK I Microprocessor Interface Clock. Microprocessor interface clock rates from twice the frequency of the line clock (4.096 MHz for CEPT operation) to 16.384 MHz are supported. * P = power, I = input, O = output, and Iu = input with internal pull-up. System Interface Pin Options The system interface can be configured to operate in a number of different modes, as shown in Table 2. Dual-rail or single-rail operation is possible using the DUAL control bit (register 5, bit 4). Dual-rail mode is enabled when DUAL = 1; single-rail mode is enabled when DUAL = 0. In dual-rail operation, data received from the line interface on RTIP and RRING appears on RPD (pins 14, 38, 64, 88) and RND (pins 13, 39, 63, 89) at the system interface and data transmitted from the system interface on TPD (pins 17, 35, 67, 85) and TND (pins 16, 36, 66, 86) appears on TTIP and TRING at the line interface. In single-rail operation, data received from the line interface on RTIP and RRING appears on RDATA (pins 14, 38, 64, 88) at the system interface and data transmitted from the system interface on TDATA (pins 17, 35, 67, 85) appears on TTIP and TRING at the line interface. In both dual-rail and single-rail operation, the clock/data recovery mode is selectable via the CDR bit (register 5, bit 0). When CDR = 1, the clock and data recovery is enabled and the system interface operates in a nonreturn to zero (NRZ) digital format. When CDR = 0, the clock and data recovery is disabled and the system interface operates on unretimed sliced data in RZ data format (see the Data Recovery section). In single-rail mode only, HDB3 encoding/decoding may be selected by setting CODE = 1 (register 5, bit 3). This allows coding violations, such as receiving two consecutive 1s of the same polarity from the line interface, to be output on BPV (pins 13, 39, 63, 89) (see the Zero Substitution Encoding/Decoding (CODE) section). Table 2. Pin Mapping Configuration RCLK/ ALOS RPD/ RDATA RND/BPV Dual-rail System Interface with Clock Recovery Dual-rail System Interface with Data Slicing Only Single-rail System Interface with Clock Recovery Single-rail System Interface with Data Slicing Only RCLK ALOS RCLK ALOS RPD RPD RDATA RPD RND RND BPV RND Lucent Technologies Inc. TPD/ TDATA TND TPD TND TDATA NOT USED 9 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Receiver Jitter Data Recovery The receiver is designed to accommodate large amounts of input jitter. The receiver jitter performance far exceeds the requirements shown in Table 4. Jitter transfer is independent of input ones density on the line interface. High-frequency jitter tolerance is a minimum of 0.4 unit intervals (UI). The receive line interface transmission format of the device is bipolar alternate mark inversion (AMI). It accepts input data with a frequency tolerance of 80 ppm (CEPT). The receiver first restores the incoming data and detects analog loss of signal. Subsequent processing is optional and depends on the programmable device configuration established within the microprocessor interface registers. The receiver operates with high interference immunity, utilizing an equalizer to restore fast rise/fall times following maximum cable loss. The signal is then peak-detected and sliced to produce digital representations of the data. Selectable clock recovery of the sliced data, digital loss of signal, jitter attenuation, and data decoding are performed. For applications bypassing the clock recovery function (CDR = 0), the receive digital output format is unretimed sliced data (RZ positive and negative data). For clock recovery applications (CDR = 1), the receive digital output format is nonreturn to zero (NRZ) with selectable dual-rail or single-rail system interface. The recovered clock (RCLK, pins 15, 37, 65, 87) is only provided when CDR = 1 (see Table 2). Timing recovery is performed by a digital phase-locked loop that uses XCLK (pin 29) as a reference to lock to the incoming data. Because the reference clock is a multiple of the received data rate, the output RCLK (pins 15, 37, 65, 87) will always be a valid CEPT clock that eliminates false-lock conditions. During periods with no input signal, the free-run frequency is defined to be XCLK/16. RCLK is always active with a duty-cycle centered at 50%, deviating by no more than 5%. Valid data is recovered within the first few bit periods after the application of XCLK. The delay of the data through the receive circuitry is approximately 1 bit to 14 bit periods, depending on the CDR and CODE configurations. Additional delay is introduced if the jitter attenuator is selected for operation in the receive path (see the Data Delay section). 10 Receiver Configuration Modes Clock/Data Recovery Mode (CDR) The clock/data recovery function in the receive path is selectable via the CDR bit (register 5, bit 0). If CDR = 1, the clock and data recovery function is enabled and provides a recovered clock (RCLK) with retimed data (RPD/RDATA, RND). If CDR = 0, the clock and data recovery function is disabled, and the RZ data from the slicers is provided over RPD and RND to the system. In this mode, ALOS is available on the RCLK/ALOS pins, and downstream functions selected by microprocessor register 5 (JAR, ACM, LOSSD) are ignored. Zero Substitution Decoding (CODE) When single-rail operation is selected with DUAL = 0 (register 5, bit 4), the HDB3 zero substitution decoding can be selected via the CODE bit (register 5, bit 3). If CODE = 1, the HDB3 decoding function is enabled in the receive path and decoded receive data and code violations appear on the RDATA and BPV pins, respectively. If CODE = 0, receive data and any bipolar violations (such as two consecutive 1s of the same polarity) appear on the RDATA and BPV pins, respectively. Alternate Logic Mode (ALM) The alternate logic mode (ALM) control bit (register 5, bit 5) selects the receive and transmit data polarity (i.e., active-high vs. active-low). If ALM = 0, the receiver circuitry (and transmit input) assumes the data to be active-low polarity. If ALM = 1, the receiver circuitry (and transmit input) assumes the data to be active-high polarity. The ALM control is used in conjunction with the ACM control (register 5, bit 6) to determine the receive data retiming mode. Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Receiver (continued) Digital Loss of Signal (DLOS) Alarm Receiver Configuration Modes (continued) A digital loss of signal (DLOS) detector guarantees the quality of the signal as defined in standards documents G.775, and reports its status to the alarm registers 0 and 1. During CEPT operation, DLOS is indicated when 255 or more consecutive 0s occur in the receive data stream. The DLOS indication is deactivated when the average ones density of at least 12.5% is received in 255 contiguous pulse positions. Alternate Clock Mode (ACM) The alternate clock mode (ACM) control bit (register 5, bit 6) selects the positive or negative clock edge of the receive clock (RCLK) for receive data retiming. The ACM control is used in conjunction with ALM (register 5, bit 5) control to determine the receive data retiming modes. If ACM = 1, the receive data is retimed on the positive edge of the receive clock. If ACM = 0, the receive data is retimed on the negative edge of the receive clock. Note that this control does not affect the timing relationship for the transmitter inputs. Loss Shut Down (LOSSD) The loss shut down (LOSSD) control bit (register 5, bit 7) places the digital receiver outputs (RPD, RND) in a predetermined state when a digital loss of signal (DLOS) alarm occurs in register 0 and 1, bits 1 and 5. If LOSSD = 1, the RPD and RND outputs are forced to their inactive states (selected by ALM) and the receive clock (RCLK) free runs during a DLOS alarm condition. If LOSSD = 0, the RPD, RND, and RCLK outputs will remain unaffected during the DLOS alarm condition. Bipolar Violation (BPV) Alarm The bipolar violation (BPV) alarm is used only in singlerail mode of operation of the device (see the System Interface Pin Options section). When HDB3(CEPT) coding is not used (i.e., CODE = 0), any violations in the receive data (such as two or more consecutive 1s on a rail) are indicated on the RND/BPV pins. When HDB3(CEPT) coding is used (i.e., CODE = 1), the HDB3 code violations are reflected on the RND/BPV pins. Receiver Alarms Analog Loss of Signal (ALOS) Alarm An analog loss of signal (ALOS) detector monitors the incoming signal amplitude and reports its status to the alarm registers 0 and 1. During CEPT mode of operation, analog loss of signal is indicated (ALOS = 1) if the amplitude at the receive input drops below a voltage that is 17 dB below the nominal pulse amplitude. The slicer outputs are clamped to the inactive state, and the clock recovery will provide a free-running RCLK when ALOS = 1. The alarm circuitry also provides 4 dB of hysteresis to eliminate ALOS chattering. The time required to detect ALOS is between 1 ms and 2.6 ms and is timed by the blue clock (see the All Ones (AIS, Blue Signal) Generator (TBS) section). Detection time is independent of signal amplitude before the loss condition occurs. Lucent Technologies Inc. 11 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Receiver (continued) CEPT Receiver Specifications During CEPT operation, the receiver will perform as specified in Table 3. Table 3. CEPT Receiver Specifications Parameter Min Typ Max Unit Analog Loss of Signal: Threshold Hysteresis 20 -- 17 4 -- -- dB* dB Maximum Sensitivity: 11 13.5 -- dB Jitter Transfer: 3 dB Bandwidth, Single-pole Rolloff Peaking -- -- 5.1 -- -- 0.5 kHz dB Generated Jitter -- 0.032 0.04 UIpk-pk ITU-T G.823, I.431 Jitter Tolerance -- -- -- -- ITU-T G.823, I.431 14 20 16 -- -- -- -- -- -- dB dB dB 255 -- -- 0s 12.5 -- -- % 1s Digital Loss of Signal: Flag Asserted, Consecutive Bit Positions Flag Deasserted ITU-T G.775 ETSI 300 233:1992 ITU-T G.703 ITU-T G.735-9 Loss: Return 51 kHz to 102 kHz 102 kHz to 2.048 MHz 2.048 MHz to 3.072 MHz Specification ITU-T G.703 ITU-T G.775 * Below the nominal pulse amplitude of 3.0 V for 120 and 2.37 V for 75 applications and using external line interface circuitry described in Figure 12 and Table 19. Amount of cable loss allowed when a -18 dB asynchronous interference signal is added with the desired signal source. Using external line interface circuitry described in Figure 12 and Table 19. 12 Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Transmitter Output Pulse Generation The transmitter accepts a clock with NRZ data in single-rail mode (DUAL = 0: register 5, bit 4) or positive and negative NRZ data in dual-rail mode (DUAL = 1) from the system. The device converts this data to a balanced bipolar signal (AMI format) with optional HDB3 encoding and jitter attenuation. Low-impedance output drivers produce these pulses on the line interface. Positive 1s are output as a positive pulse on TTIP, and negative 1s are output as a positive pulse on TRING. Binary 0s are converted to null pulses. The total delay of the data from the system interface to the transmit driver is approximately 3 to 11 bit periods, depending on the CODE (register 5, bit 3) configuration. Additional delay results if the jitter attenuator is selected for use in the transmit path (see the Data Delay section). Transmit pulse shaping is controlled by the on-chip pulse-width controller and pulse equalizer. The pulse-width controller produces the high-speed timing signals to accurately control the transmit pulse widths. This eliminates the need for a tightly controlled transmit clock duty cycle that is usually required in discrete implementations. The pulse equalizer controls the amplitudes of these pulse shapes. Different pulse equalizations are selected through proper settings of EQA, EQB, and EQC (registers 6 to 9, bits 5 to 7) as described in Table 4. Table 4. Equalizer/Rate Control EQA* EQB* EQC* Service Clock Rate Transmitter Equalization 1 1 0 1 1 0 CEPT 2.048 MHz 75 (Option 2) 120 or 75 (Option 1) * Other logical settings of EQA, EQB, and EQC should not be used. In CEPT mode, equalization is specified for coaxial or twisted-pair cable. In 75 applications, Option 1 is recommended over Option 2 for lower device power dissipation. Option 2 allows for the same transformer as used in CEPT 120 applications. Jitter The intrinsic jitter of the transmit path, i.e., the jitter at TTIP/TRING when no jitter is applied to TCLK (and the jitter attenuator is not selected, JAT = 0), is typically 5 nspk-pk and will not exceed 0.02 UIpk-pk. Lucent Technologies Inc. 13 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Transmitter (continued) Transmitter Alarms Transmitter Configuration Modes Loss of Transmit Clock (LOTC) Alarm Zero Substitution Encoding/Decoding (CODE) A loss of transmit clock alarm (LOTC = 1) is indicated if any of the clocks in the transmit path disappear (registers 0 and 1, bits 3 and 7). This includes loss of TCLK input, loss of RCLK during remote loopback, loss of jitter attenuator output clock (when enabled), or the loss of clock from the pulse-width controller. Zero substitution encoding/decoding (HDB3) can be activated only in the single-rail system interface mode (DUAL = 0) by setting CODE = 1 (register 5, bit 3). Data received from the line interface on RTIP and RRING will be HDB3 decoded before appearing on RDATA (pins 14, 38, 64, 88) at the system interface. Likewise, data transmitted from the system interface on TDATA (pins 17, 35, 67, 85) will be HDB3 encoded before appearing on TTIP and TRING at the line interface. This mode also allows coding violations, such as receiving two consecutive 1s of the same polarity from the line interface, to be output on BPV (pins 13, 39, 63, 89). All Ones (AIS, Blue Signal) Generator (TBS) When the transmit blue signal control is set (TBS = 1) for a given channel (registers 6 to 9, bit 2), a continuous stream of bipolar 1s is transmitted to the line interface (AIS). The TPD/TDATA and TND inputs are ignored during this mode. The TBS input is ignored when a remote loopback (RLOOP) is selected using loopback control bits LOOPA and LOOPB (registers 6 to 9, bits 3 and 4). (See the Loopbacks section.) To maintain application flexibility, the clock source used for the blue signal is selected by configuring BCLK (pin 30). If a data rate clock is input on the BCLK pin, it will be used to transmit the blue signal. If BCLK = 0, then TCLK is used to transmit the blue signal (the smoothed clock from the jitter attenuator is used if JAT = 1 is selected). If BCLK = 1, then XCLK (after being divided by a factor of 16) is used to transmit the blue signal. After BCLK is established, a minimum of 16 s is required for the device to properly select the clock. For any of the above options, the clock tolerance must meet the normal line transmission rate (2.048 MHz 50 ppm). For all of these conditions, a core transmitter timing clock is lost and no data can be driven onto the line. Output drivers TTIP and TRING are placed in a highimpedance state when this alarm condition is active. The LOTC interrupt is asserted between 3 s and 16 s after the clock disappears, and deasserts immediately after detecting the first clock edge. Transmit Driver Monitor (TDM) Alarm The transmit driver monitor detects two conditions: a nonfunctional link due to faults on the primary of the transmit transformer, and periods of no data transmission. The TDM alarm (registers 0 and 1, bits 2 and 6) is the ORed function of both faults and provides information about the integrity of the transmit signal path. The first monitoring function is provided to detect nonfunctional links and protect the device from damage. The alarm is set (TDM = 1) when one of the transmitter's line drivers (TTIP or TRING) is shorted to power supply or ground, or TTIP and TRING are shorted together. Under these conditions, internal circuitry protects the device from damage and excessive power supply current consumption by 3-stating the output drivers. The monitor detects faults on the transformer primary, but transformer secondary faults may not be detected. The monitor operates by comparing the line pulses with the transmit inputs as in a bit error detect mode. After 32 transmit clock cycles, the transmitter is powered up in its normal operating mode. The drivers attempt to correctly transmit the next data bit. If the error persists, TDM remains active to eliminate alarm chatter and the transmitter is internally protected for another 32 transmit clock cycles. This process is repeated until the error condition is removed and the TDM alarm is deactivated. The second monitoring function is to indicate periods of no data transmission. The alarm is set (TDM = 1) when 32 consecutive zeros have been transmitted and is cleared on the detection of a single pulse. This alarm condition does not alter the state or functionality of the signal path. 14 Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Transmitter (continued) CEPT Transmitter Pulse Template and Specifications CEPT pulse shape template is specified at the system output (defined by ITU-T G.703) and is illustrated in Figure 3. 269 ns (244 + 25) 20% 10% V = 100% 194 ns (244 - 50) 10% NOMINAL PULSE 20% 50% 244 ns 219 ns (244 - 25) 10% 10% 10% 10% 0% 20% 488 ns (244 + 244) 5-3145(C)r.7 Figure 3. ITU-T G.703 Pulse Template During CEPT operation, the transmitter tip/ring (TTIP/TRING pins) will perform as specified in Table 5. Table 5. CEPT Transmitter Specifications Parameter Output Pulse Amplitude:* 75 120 Output Pulse Width Positive/Negative Pulse Imbalance: Pulse Amplitude Pulse Width Zero Level (percentage of pulse amplitude) Return Loss: 51 kHz to 102 kHz 102 kHz to 2.048 MHz 2.048 MHz to 3.072 MHz Min Typ Max Unit 2.13 2.7 232 2.37 3.0 244 2.61 3.3 256 V V ns -4 -4 -5 1.5 1.0 0 4 4 5 % % % 9 15 11 -- -- -- -- -- -- dB dB dB Specification ITU-T G.703 CH-PTT * In accordance with the interfaces described in the Absolute Maximum Ratings section and the Handling Precautions section, the output pulse amplitude is measured at the transformer secondary. Using external line interface circuitry described in Figure 12 and Table 19. Lucent Technologies Inc. 15 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Jitter Attenuator Jitter Transfer Function The selectable jitter attenuator is provided for narrowbandwidth jitter transfer function applications. The selection is done via control bits which are global and affect all four channels. One application is to provide narrow-bandwidth jitter filtering for line-synchronization in the receive path. Another use of the jitter attenuator is to provide clock smoothing in the transmit signaling path for applications such as synchronous/asynchronous demultiplexers. In these applications, TCLK will have an instantaneous frequency that is higher than the data rate and periods of TCLK are suppressed (gapped) in order to set the average long-term TCLK frequency to within the transmit line rate specification. The jitter transfer function describes the amount of jitter in specific equipment that is transferred from the input to the output over a frequency range. The jitter attenuator exhibits a single-pole rolloff (20 dB/decade) jitter transfer characteristic that has no peaking and a nominal filter corner frequency (3 dB bandwidth) for CEPT operation of less than 10 Hz. For a given frequency, different jitter amplitudes will cause slight variations in attenuation because of finite quantization effects. Jitter amplitudes of less than approximately 0.2 UI will have greater attenuation than the single-pole rolloff characteristic. The jitter attenuator does not degrade the jitter specifications of the receiver clock/data recovery circuit. In addition, the jitter attenuator must meet the specifications for narrow-bandwidth applications as listed in Table 6. Table 6. List of Low Bandwidth Jitter Specification Documents Application CEPT ITU-T G.735 ITU-T I.431 Measurement of the jitter transfer function involves stimulating the circuit with a sinusoidal jitter test signal. The difference between the output signal power and the test signal power, at a given frequency, is the jitter transfer. When output signal power is below the noise floor, it cannot be measured. Halting the jitter transfer function measurements because of noise floor limitations is acceptable during conformance testing. Jitter Tolerance The minimum jitter tolerance of the jitter attenuator occurs when the XCLK frequency and the long-term average frequency of the input clock are at their extreme frequency tolerances. The minimum tolerance is 28 U.I. peak-to-peak at the highest jitter frequency of 15 kHz. Data Delay Providing narrow-bandwidth jitter filtering requires data buffering to increase the data delay through the jitter attenuator. The nominal data delay for the jitter attenuator is 33 bit periods, with a maximum data delay of 66 bit periods. This delay is dependent on the input clock frequency, XCLK frequency, input jitter, and gapped clock patterns. Generated (Intrinsic) Jitter Generated jitter is the amount of jitter appearing on the output port when the applied input signal has no jitter. The jitter attenuator of this device outputs a maximum of 0.04 UI peak-to-peak intrinsic jitter. 16 Jitter Attenuator Enable The jitter attenuator is selected using the JAR and JAT bits (register 5, bits 1 and 2) of the microprocessor interface. These control bits are global and affect all four channels unless a given channel is in the powerdown mode (PWRDN = 1). Because there is only one attenuator function in the device, selection must be made between either the transmit or receive path. If both JAT and JAR are activated at the same time, the jitter attenuator will be disabled. Note that the power consumption increases slightly on a per-channel basis when the jitter attenuator is active, as described in Table 24. If jitter attenuation is selected, a valid XCLK (pin 29) signal must be available. Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Jitter Attenuator (continued) Full Local Loopback (FLLOOP) Jitter Attenuator Enable (continued) A full local loopback (FLLOOP) connects the transmit line driver input to the receiver analog front-end circuitry. Valid transmit output data continues to be sent to the network. If the transmit blue signal (all-1s signal) is sent to the network, the looped data is not affected. The ALOS alarm continues to monitor the receive line interface signal while DLOS monitors the looped data. Jitter Attenuator Receive Path Enable (JAR) When the jitter attenuator receive bit is set (JAR = 1), the attenuator is enabled in the receive data path between the clock/data recovery and the decoder (see Figure 1). Under this condition, the jitter characteristics of the jitter attenuator apply for the receiver. When JAR = 0, the clock/data recovery outputs bypass the disabled attenuator and directly enter the decoder function. The receive path will then exhibit the jitter characteristics of the clock recovery function as described in the Jitter section. If CDR = 0 (register 5, bit 0), the JAR bit is ignored because clock recovery will be disabled. Jitter Attenuator Transmit Path Enable (JAT) When the jitter attenuator transmit bit is set (JAT = 1), the attenuator is enabled in the transmit data path between the encoder and the pulse-width controller/ pulse equalizer (see Figure 1). Under this condition, the jitter characteristics of the jitter attenuator apply for the transmitter. When JAT = 0, the encoder outputs bypass the disabled attenuator and directly enter the pulse-width controller/pulse equalizer. The transmit path will then pass all jitter from TCLK to line interface outputs TTIP/TRING. Loopbacks Remote Loopback (RLOOP) A remote loopback (RLOOP) connects the recovered clock and retimed data to the transmitter at the system interface and sends the data back to the line. The receiver front end, clock/data recovery, encoder/ decoder (if enabled) jitter attenuator (if enabled), and transmit driver circuitry are all exercised during this loopback. The transmit clock, transmit data, and TBS inputs are ignored. Valid receive output data continues to be sent to the system interface. This loopback mode is very useful for isolating failures between systems. Digital Local Loopback (DLLOOP) A digital local loopback (DLLOOP) connects the transmit clock and data through the encoder/decoder pair to the receive clock and data output pins at the system interface. This loopback is operational if the encoder/ decoder pair is enabled or disabled. The blue signal can be transmitted without any effect on the looped signal. The device has three independent loopback paths that are activated using LOOPA and LOOPB (registers 6 to 9, bits 3 and 4) as shown in Table 7. The locations of these loopbacks are illustrated in Figure 1. Table 7. Loopback Control Operation Symbol LOOPA LOOPB -- 0 0 Full Local Loopback FLLOOP* 0 1 Remote Loopback RLOOP 1 0 Digital Local Loopback DLLOOP 1 1 Normal * During the transmit blue signal condition, the looped data will be the transmitted data from the system and not the all-1s signal. Transmit blue signal request is ignored. Lucent Technologies Inc. 17 T7688 5.0 V E1/CEPT Quad Line Interface Data Sheet May 1998 Other Features Loss of XCLK Reference Clock (LOXC) Powerdown (PWRDN) The LOXC output (pin 31) is active when the XCLK reference clock (pin 29) is absent. The LOXC flag is asserted between 150 ns and 700 ns after XCLK disappears, and deasserts immediately after detecting the first clock edge of XCLK. Each line interface channel has an independent powerdown mode controlled by PWRDN (registers 6 to 9, bit 0). This provides power savings for systems that use backup channels. If PWRDN = 1, the corresponding channel will be in a standby mode, consuming only a small amount of power. It is recommended that the alarm registers for the corresponding channel be masked with MASK = 1 (registers 6 to 9, bit 1) during powerdown mode. If a line interface channel in powerdown mode needs to be placed into service, the channel should be turned on (PWRDN = 0) approximately 5 ms before data is applied. If a line interface channel will never be in service, the VDDA and VDDD pins can be connected to the ground plane, resulting in no power consumption. RESET (RESET, SWRESET) The device provides both a hardware reset (RESET; pin 32) and a software reset (SWRESET; register 4, bit 1) that are functionally equivalent. When the device is in reset, all signal-path and alarm monitor states are initialized to a known starting configuration. The status registers and INT (pin 25) are also cleared. The writable microprocessor interface registers are not affected by reset, with the exception of bits in register 4 (see the Global Control Register Overview (0100, 0101) section). During a reset condition, data transmission will be momentarily interrupted and the device will respond to those register bits affected by the reset. On powerup of the device, the software reset bit (register 4, bit 1) is not initialized. It must be written to a zero prior to writing the other bits in register 4. During the LOXC alarm condition, the clock recovery and jitter attenuator functions are automatically disabled. Therefore, if CDR = 1 and/or JAR = 1, the RCLK, RPD, RND, and DLOS outputs will be unknown. If CDR = 0, there will be no effect on the receiver. If the jitter attenuator is enabled in the transmit path (JAT = 1) during this alarm condition, then LOTC = 1 will also be indicated. In-Circuit Testing and Driver 3-State (ICT) The function of the ICT input (pin 33) is determined by the ICTMODE bit (register 4, bit 3). If ICTMODE = 0 and ICT is activated (ICT = 0), then all output buffers (TTIP, TRING, RCLK, RPD, RND, LOXC, RDY_DTACK, INT, AD[7:0]) are placed in a high-impedance state. For in-circuit testing, the RESET pin can be used to activate ICTMODE = 0 without having to write the bit. If ICTMODE = 1 and ICT = 0, then only the TTIP and TRING outputs of all channels will be placed in a highimpedance state. The TTIP and TRING outputs have a limiting high-impedance capability of approximately 8 k. The reset condition is initiated by setting RESET = 0 or SWRESET = 1 for a minimum of 10 s. After leaving the reset condition (with RESET = 1 or SWRESET = 0), only the bits in register 4 need to be restored. 18 Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Microprocessor Interface Overview The device is equipped with a microprocessor interface that can operate with most commercially available microprocessors. Inputs MPMUX and MPMODE (pins 20 and 21) are used to configure this interface into one of four possible modes, as shown in Table 8. The MPMUX setting selects either a multiplexed 8-bit address/data bus (AD[7:0]) or a demultiplexed 4-bit address bus (A[3:0]) and an 8-bit data bus (AD[7:0]). The MPMODE setting selects the associated set of control signals required to access a set of registers within the device. When the microprocessor interface is configured to operate in the multiplexed address/data bus modes (MPMUX = 1), the user has access to an internal chip select function that allows the microprocessor to selectively read/write a specific T7688 in a multiple T7688 environment (see the Internal Chip Select Function section). The microprocessor interface can operate at speeds up to 16.384 MHz in interrupt-driven or polled mode without requiring any wait-states. For microprocessors operating at greater than 16.384 MHz, the RDY_DTACK output is used to introduce wait-states in the read/write cycles. In the interrupt-driven mode, one or more device alarms will assert the active-high INT output (pin 25) once per alarm activation. After the microprocessor reads the alarm status registers, the INT output will deassert. In the polled mode, however, the microprocessor monitors the various device alarm status by periodically reading the alarm status registers without the use of INT (pin 25). In both interrupt and polled methods of alarm servicing, the status register will clear on a microprocessor read cycle only when the alarm condition within the signaling channel no longer exists; otherwise, the register bit remains set. Due to the device flexibility, there are no default powerup or reset states, except for register 4. All read/write registers must be written by the microprocessor on system start-up to guarantee proper device functionality. Details concerning microprocessor interface configuration modes, pinout definitions, clock specifications, register bank architecture, and the I/O timing specifications and diagrams are described in the following sections. Microprocessor Configuration Modes Table 8 highlights the four microprocessor modes controlled by the MPMUX and MPMODE inputs (pins 20 and 21). Table 8. Microprocessor Configuration Modes Mode MPMODE MPMUX Address/Data Bus MODE1 MODE2 MODE3 MODE4 0 0 1 1 0 1 0 1 DEMUXed MUXed DEMUXed MUXed Lucent Technologies Inc. Generic Control, Data, and Output Pin Names CS, AS, DS, R/W, A[3:0], AD[7:0], INT, DTACK CS, AS, DS, R/W, AD[7:0], INT, DTACK CS, ALE, RD, WR, A[3:0], AD[7:0], INT, RDY CS, ALE, RD, WR, AD[7:0], INT, RDY 19 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Microprocessor Interface (continued) Microprocessor Interface Pinout Definitions The MODE1 through MODE4 specific pin definitions are given in Table 9. Note that the microprocessor interface uses the same set of pins in all modes. Table 9. MODE [1--4] Microprocessor Pin Definitions Configuration Pin Number Device Pin Name Generic Pin Name Pin Type Assertion Sense MODE1 19 WR_DS DS I Active-Low 22 RD_R/W R/W I -- 23 24 25 26 69--76 79--82 83 ALE_AS CS INT RDY_DTACK AD[7:0] A[3:0] MPCLK AS CS INT DTACK AD[7:0] A[3:0] MPCLK I I O O I/O I I -- Active-Low Active-High Active-Low -- -- -- 19 22 WR_DS RD_R/W DS R/W I I Active-Low -- 23 24 25 26 69--76 83 ALE_AS CS INT RDY_DTACK AD[7:0] MPCLK AS CS INT DTACK AD[7:0] MPCLK I I O O I/O I -- Active-Low Active-High Active-Low -- -- Data Strobe Read/Write R/W = 1 => Read R/W = 0 => Write Address Strobe Chip Select Interrupt Data Acknowledge Address/Data Bus Microprocessor Clock MODE3 19 22 23 24 25 26 69--76 79--82 83 WR_DS RD_R/W ALE_AS CS INT RDY_DTACK AD[7:0] A[3:0] MPCLK WR RD ALE CS INT RDY AD[7:0] A[3:0] MPCLK I I I I O O I/O I I Active-Low Active-Low -- Active-Low Active-High Active-High -- -- -- Write Read Address Latch Enable Chip Select Interrupt Ready Data Bus Address Bus Microprocessor Clock MODE4 19 22 23 24 25 26 69--76 83 WR_DS RD_R/W ALE_AS CS INT RDY_DTACK AD[7:0] MPCLK WR RD ALE CS INT RDY AD[7:0] MPCLK I I I I O O I/O I Active-Low Active-Low -- Active-Low Active-High Active-High -- -- Write Read Address Latch Enable Chip Select Interrupt Ready Address/Data Bus Microprocessor Clock MODE2 20 Function Data Strobe Read/Write R/W = 1 => Read R/W = 0 => Write Address Strobe Chip Select Interrupt Data Acknowledge Data Bus Address Bus Microprocessor Clock Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Microprocessor Interface (continued) Microprocessor Clock (MPCLK) Specifications The microprocessor interface is designed to operate at clock speeds up to 16.384 MHz without requiring any waitstates. Wait-states may be needed if higher microprocessor clock speeds are required. The microprocessor clock (MPCLK, pin 83) specification is shown in Table 10. This clock must be supplied only if the RDY_DTACK and INT outputs are required to be synchronous to MPCLK. Otherwise, the MPCLK pin must be connected to ground (GNDD). Table 10. Microprocessor Input Clock Specifications Name MPCLK Symbol t1 Period and Tolerance 61 to 323 Trise Typ 5 Tfall Typ 5 Duty Cycle Min High Min Low 27 27 Unit ns Internal Chip Select Function When the microprocessor interface is configured to operate in the multiplexed address/data bus modes (MPUX = 1), the user has access to an internal chip select function. This function allows a microprocessor to selectively read or write a specific quad line interface device in a system of up to eight devices on the microprocessor bus. Externally tying CS = 0 (pin 24) and A3 = 1 (pin 79) on every line interface device enables the internal chip select function. Individual device addresses are established by externally connecting the other three address pins A[2:0] to a unique address value in the range of 000 through 111. In order for a line interface device to respond to the register read or write request from the microprocessor, the address data bus AD[6:4] (pins 70, 71, 72) must match the specific address defined on A[2:0]. If CS and A3 pins are tied low, the internal chip select function is disabled and all line interface devices will respond to a microprocessor write request. However, if CS = 1, none of the line interface devices will respond to the microprocessor read/write request. Microprocessor Interface Register Architecture The register bank architecture of the microprocessor interface is shown in Table 11. The register bank consists of sixteen 8-bit registers classified as alarm registers, global control registers, and channel configuration/maintenance registers. Registers 0 and 1 are the alarm registers used for storing the various device alarm status and are read-only. All other registers are read/write. Registers 2 and 3 contain the individual mask bits for the alarms in registers 0 and 1. Registers 4 and 5 are designated as the global control registers used to set up the functions for all four channels. The channel configuration registers in registers 6 through 9 are used to configure the individual channel functions and parameters. Registers 10 and 11 must be cleared by the user after a powerup for proper device operation. Registers 12 through 15 are reserved for proprietary functions and must not be addressed during operation. The following sections describe these registers in detail. Lucent Technologies Inc. 21 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Microprocessor Interface (continued) Microprocessor Interface Register Architecture (continued) Table 11. Register Set Designation Address Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Alarm Registers (Read Only) 0 0000 LOTC2 TDM2 DLOS2 ALOS2 LOTC1 TDM1 DLOS1 ALOS1 1 0001 LOTC4 TDM4 DLOS4 ALOS4 LOTC3 TDM3 DLOS3 ALOS3 Alarm Mask Registers (Read/Write) 2 0010 MLOTC2 MTDM2 MDLOS2 MALOS2 MLOTC1 MTDM1 MDLOS1 MALOS1 3 0011 MLOTC4 MTDM4 MDLOS4 MALOS4 MLOTC3 MTDM3 MDLOS3 MALOS3 4 0100 HIGHZ4 (1) HIGHZ3 (1) 0 SWRESET GMASK (1) 5 0101 LOSSD ACM JAT JAR CDR 6 0110 EQA1 EQB1 EQC1 LOOPA1 LOOPB1 TBS1 MASK1 PWRDN1 7 0111 EQA2 EQB2 EQC2 LOOPA2 LOOPB2 TBS2 MASK2 PWRDN2 8 1000 EQA3 EQB3 EQC3 LOOPA3 LOOPB3 TBS3 MASK3 PWRDN3 9 1001 EQA4 EQB4 EQC4 LOOPA4 LOOPB4 TBS4 MASK4 PWRDN4 10 1010 0 0 0 0 0 0 0 0 11 1011 0 0 0 0 0 0 0 0 12--15 1100--1111 Global Control Registers (Read/Write) HIGHZ2 (1) HIGHZ1 (1) ICTMODE (0) ALM DUAL CODE Channel Configuration Registers (Read/Write) RESERVED Notes: A numerical suffix appended to the bit name identifies the channel number. Bits shown in parentheses indicate the state forced during a reset condition. All registers must be configured by the user before the device can operate as required for the particular application. Registers 10 and 11 MUST be written to 0 after powerup of the device. It is recommended that registers 12--15 be written to 0 after powerup of the device. 22 Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Microprocessor Interface (continued) Microprocessor Interface Register Architecture (continued) Alarm Register Overview (0000, 0001) The bits in the alarm registers represent the status of the transmitter and receiver alarms LOTC, TDM, DLOS, and ALOS for all four channels as shown in Table 13. The alarm indicators are active-high and automatically clear on a microprocessor read if the corresponding alarm condition no longer exists. Persistent alarm conditions will cause the bit to remain set. These are read-only registers. Table 12. Alarm Registers Bits Symbol* 0, 4 1, 5 2, 6 3, 7 ALOS[1:2] DLOS[1:2] TDM[1:2] LOTC[1:2] 0, 4 1, 5 2, 6 3, 7 Description Alarm Register (0) Analog loss of signal alarm for channels 1 & 2. Digital loss of signal alarm for channels 1 & 2. Transmit driver monitor alarm for channels 1 & 2. Loss of transmit clock alarm for channels 1 & 2. Alarm Register (1) ALOS[3:4] Analog loss of signal alarm for channels 3 & 4. DLOS[3:4] Digital loss of signal alarm for channels 3 & 4. TDM[3:4] Transmit driver monitor alarm for channels 3 & 4. LOTC[3:4] Loss of transmit clock alarm for channels 3 & 4. * The numerical suffix identifies the channel number. Alarm Mask Register Overview (0010, 0011) The bits in the alarm mask registers in Table 13 allow the microprocessor to selectively mask each channel alarm and prevent it from generating an interrupt. The mask bits correspond to the alarm status bits in the alarm registers and are active-high to disable the corresponding alarm from generating an interrupt. These registers are read/write registers. Table 13. Alarm Mask Registers Bits Symbol* Description 0, 4 MALOS[1:2] Mask analog loss of signal alarm for channels 1 & 2. 1, 5 MDLOS[1:2] Mask digital loss of signal alarm for channels 1 & 2. 2, 6 MTDM[1:2] Mask transmit driver monitor alarm for channels 1 & 2. 3, 7 MLOTC[1:2] Mask loss of transmit clock alarm for channels 1 & 2. 0, 4 MALOS[3:4] Mask analog loss of signal alarm for channels 3 & 4. 1, 5 MDLOS[3:4] Mask digital loss of signal alarm for channels 3 & 4. 2, 6 MTDM[3:4] Mask transmit driver monitor alarm for channels 3 & 4. 3, 7 MLOTC[3:4] Mask loss of transmit clock alarm for channels 3 & 4. Alarm Mask Register (2) Alarm Mask Register (3) * The numerical suffix identifies the channel number. Lucent Technologies Inc. 23 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Microprocessor Interface (continued) Microprocessor Interface Register Architecture (continued) Global Control Register Overview (0100, 0101) The bits in the global control registers in Table 14 and Table 15 allow the microprocessor to configure the various device functions over all the four channels. All the control bits (with the exception of LOSSTD and ICTMODE) are active-high. These are read/write registers. Table 14. Global Control Register (0100) Bits Symbol Description Global Control Register (4) 0 GMASK The GMASK bit globally masks all the channel alarms when GMASK = 1, preventing all the receiver and transmitter alarms from generating an interrupt. GMASK = 1 after a device reset. 1 SWRESET The SWRESET provides the same function as the hardware reset. It is used for device initialization through the microprocessor interface. The software reset bit does not have a powerup default state, therefore, the first write to the device must clear this bit. 2 LOSSTD 3 ICTMODE The ICTMODE bit changes the function of the ICT pin. ICTMODE = 0 after a device reset. 4--7 HIGHZ[1:4] A HIGHZ bit is available for each individual channel. When HIGHZ = 1, the TTIP and TRING transmit drivers for the specified channel are placed in a high-impedance state. HIGHZ[1:4] = 1 after a device reset. The LOSSTD bit must be written to 0. Table 15. Global Control Register (0101) Bits 24 Symbol 0 1 CDR JAR 2 JAT 3 CODE 4 5 DUAL ALM 6 ACM 7 LOSSD Description Global Control Register (5) The CDR bit is used to enable and disable the clock/data recovery function. The JAR is used to enable and disable the jitter attenuator function in the receive path. The JAR and JAT control bits are mutually exclusive; i.e., either JAR or the JAT control bit can be set, but not both. The JAT is used to enable and disable the jitter attenuator function in the transmit path. The JAT and JAR control bits are mutually exclusive; i.e., either JAT or the JAR control bit should be set, but not both. The CODE bit is used to enable and disable the HDB3 zero substitution coding (decoding) in the transmit (receive) path. It is used in conjunction with the DUAL bit and is valid only for single-rail operation. The DUAL bit is used to select single- or dual-rail mode of operation. The ALM bit selects the transmit and receive data polarity (i.e., active-low or active-high). The ALM and ACM bits are used together to determine the transmit and receive data retiming modes. The ACM bit selects the positive or negative edge of the receive clock (RCLK[1:4]) for receive data retiming. The ACM and ALM bits are used together to determine the transmit and receive data retiming modes. The LOSSD bit selects the shutdown function for the digital loss of signal alarm (DLOS). Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Microprocessor Interface (continued) Microprocessor Interface Register Architecture (continued) Channel Configuration Register Overview (0110--1001) The control bits in the channel configuration registers in Table 16 are used to select equalization, loopbacks, AIS generation, channel alarm masking, and the channel powerdown mode for each channel (1--4). The PWRDN[1--4], MASK[1--4], and TBS[1--4] bits are active-high. These are read/write registers. Table 16. Channel Configuration Registers Bits Symbol* 0 1 2 3, 4 5, 6, 7 PWRDN[1:4] MASK[1:4] TBS[1:4] LOOPB[1:4], LOOPA[1:4] EQC[1:4], EQB[1:4], EQA[1:4] Description Channel Configuration Registers (6--9) The PWRDN bit powers down a channel when not used. The MASK bit masks all interrupts for the channel. The TBS bit enables transmission of an all 1s signal to the line interface. The LOOPB and LOOPA bits select the channel loopback modes. The EQC, EQB, and EQA bits select the type of service (CEPT 75 or CEPT 120 ) and the associated transmitter cable equalization/termination impedances. * A numerical suffix identifies the channel number. Channel suffix not shown in the description. Other Registers The bits in registers 10 and 11 must be cleared by the microprocessor after a device powerup. The software reset bit must be cleared after powerup prior to writing any other bits in register 4. Lucent Technologies Inc. 25 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Microprocessor Interface (continued) I/O Timing The I/O timing specifications for the microprocessor interface are given in Table 17. The microprocessor interface pins use CMOS I/O levels. All outputs, except the address/data bus AD[7:0], are rated for a capacitive load of 50 pF. The AD[7:0] outputs are rated for a 100 pF load. The minimum read and write cycle time is 200 ns for all device configurations. Table 17. Microprocessor Interface I/O Timing Specifications Symbol Configuration t1 t2 t3 t4 Modes 1 & 2 Parameter Address Valid to AS Asserted (Read, Write) AS Asserted to Address Invalid (Read, Write) AS Asserted to DS Asserted R/W High (Read) to DS Asserted t5 t6 t7 DS Asserted (Read, Write) to DTACK Asserted t8 t9 DS Negated (Read, Write) to AS Negated DTACK Asserted to Data Valid (Read) DS Asserted (Read) to Data Valid DS Negated (Read) to Data Invalid t10 t11 t12 DS Negated (Read) to DTACK Negated t13 t14 AS Asserted to R/W Low (Write) AS (Read, Write) Asserted Width DS (Read) Asserted Width R/W Low (Write) to DS Asserted t15 t16 t17 Data Valid to DS Negated (Write) DS Negated to DTACK Negated (Write) t18 t19 DS (Write) Asserted Width DS Negated to Data Invalid (Write) Setup (ns) Hold (ns) Delay (ns) (Min) (Min) (Max) 15 -- 50 -- 10 -- -- -- -- 25 -- -- -- -- -- -- 20 70 -- -- -- -- 90 25 -- -- -- -- -- 150 15 15 -- -- 25 100 -- -- -- 25 25 -- -- -- -- -- -- 20 25 100 -- -- -- -- Address Valid to ALE Asserted Low (Read, Write) -- -- 15 t20 t21 t22 t23 t24 t25 t26 t27 t28 t29 t30 ALE Asserted Low (Read, Write) to Address Invalid ALE Asserted Low to RD Asserted (Read) -- 30 10 -- -- -- RD Asserted (Read) to Data Valid RD Negated to RDY Negated (Read) -- -- -- -- -- -- -- -- 90 75 20 25 ALE Asserted Low to WR Asserted (Write) CS Asserted to RDY Asserted Low Data Valid to WR Negated (Write) WR Asserted (Write) to RDY Asserted WR Negated to RDY Negated (Write) 30 -- 25 -- -- -- -- -- -- -- -- 16 -- 73 22 t31 t32 t33 t34 WR Negated to Data Invalid ALE Asserted (Read, Write) Width RD Asserted (Read) Width WR Asserted (Write) Width -- -- -- -- 25 150 100 100 -- -- -- -- Modes 3 & 4 RD Asserted (Read) to RDY Asserted RD Negated to Data Invalid (Read) The read and write timing diagrams for all four microprocessor interface modes are shown in Figures 4--11. 26 Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Microprocessor Interface (continued) I/O Timing (continued) MINIMUM READ CYCLE CS t11 AS t2 t1 t8 A[3:0] VALID ADDRESS R/W t4 t3 t12 DS t6 t5 t10 DTACK t9 t7 AD[7:0] VALID DATA 5-3685(C)r.6 Figure 4. Mode1--Read Cycle Timing (MPMODE = 0, MPMUX = 0) MINIMUM WRITE CYCLE CS t11 AS t2 t1 t8 A[3:0] VALID ADDRESS t13 t14 R/W t18 DS t5 t16 DTACK t15 AD[7:0] t17 VALID DATA 5-3686(C)r.6 Figure 5. Mode1--Write Cycle Timing (MPMODE = 0, MPMUX = 0) Lucent Technologies Inc. 27 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Microprocessor Interface (continued) I/O Timing (continued) MINIMUM READ CYCLE CS t11 AS t8 R/W t4 t3 t12 DS t7 t5 t6 t10 DTACK t2 t1 AD[7:0] VALID DATA t9 VALID ADDRESS VALID ADDRESS VALID DATA 5-3687(C)r.9 Figure 6. Mode2--Read Cycle Timing (MPMODE = 0, MPMUX = 1) MINIMUM WRITE CYCLE CS t11 AS t13 t8 t14 R/W t18 DS t5 t16 DTACK t2 t1 AD[7:0] VALID DATA VALID ADDRESS t15 VALID DATA t17 VALID ADDRESS 5-3688(C)r.9 Figure 7. Mode2--Write Cycle Timing (MPMODE = 0, MPMUX = 1) 28 Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Microprocessor Interface (continued) I/O Timing (continued) MINIMUM READ CYCLE CS t32 ALE t19 t20 VALID ADDRESS A[3:0] t21 t33 RD t24 t22 AD[7:0] VALID DATA t25 t23 t27 RDY 5-3689(C)r.6 Figure 8. Mode3--Read Cycle Timing (MPMODE = 1, MPMUX = 0) MINIMUM WRITE CYCLE CS t32 ALE t19 t20 VALID ADDRESS A[3:0] t26 t34 WR t31 t28 AD[7:0] VALID DATA t29 t27 t30 RDY 5-3690(C)r.7 Figure 9. Mode3--Write Cycle Timing (MPMODE = 1, MPMUX = 0) Lucent Technologies Inc. 29 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Microprocessor Interface (continued) I/O Timing (continued) MINIMUM READ CYCLE CS t32 ALE t21 t33 RD t19 AD[7:0] t24 t22 VALID ADDRESS VALID DATA t20 t27 VALID ADDRESS VALID DATA t25 t23 RDY 5-3691(C)r.9 Figure 10. Mode4--Read Cycle Timing (MPMODE = 1, MPMUX = 1) MINIMUM WRITE CYCLE CS t32 ALE t26 t34 WR t19 t20 AD[7:0] VALID ADDRESS VALID DATA t27 t28 t31 VALID ADDRESS VALID DATA t29 t30 RDY 5-3692(C)r.10 Figure 11. Mode4--Write Cycle Timing (MPMODE = 1, MPMUX = 1) 30 Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface XCLK Reference Clock The device requires a high-frequency reference clock for both clock/data recovery and jitter attenuation options (CDR = 1, JAR = 1, or JAT = 1). The XCLK signal (pin 29) is conditionally required if the MPCLK signal (pin 83) is not supplied for interrupt generation in the microprocessor interface. For any other device configuration, XCLK is not required. If it is required, XCLK must be a continuously active (i.e., ungapped, unjittered, and unswitched) and an independent reference clock, such as an external system oscillator or system clock, for proper operation. It must not be derived from any recovered line clock (i.e., from RCLK or any synthesized frequency of RCLK). The specifications for XCLK are defined in Table 18. Table 18. XCLK Timing Specifications Parameter Frequency: CEPT Range Duty Cycle Value Min Typ Max -- -100 40 32.768 -- -- -- 100 60 Unit MHz ppm % Power Supply Bypassing External bypassing is required for all channels. A 1.0 F capacitor must be connected between VDDX and GNDX. In addition, a 0.1 F capacitor must be connected between VDDD and GNDD, and a 0.1 F capacitor must be connected between VDDA and GNDA. Ground plane connections are required for GNDX, GNDD, and GNDA. Power plane connections are also required for VDDX and VDDD. The need to reduce high-frequency coupling into the analog supply (VDDA) may require an inductive bead to be inserted between the power plane and the VDDA pin of every channel. External bypassing is also required for the microprocessor power supply pins. A 0.1 F capacitor must be connected between every pair of VDDC and GNDC pins. VDDC and GNDC are connected directly to the power and ground planes, respectively. Capacitors used for power supply bypassing should be placed as close as possible to the device pins for maximum effectiveness. Lucent Technologies Inc. 31 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface External Line Interface Circuitry The transmit and receive tip/ring connections provide a matched interface to the cable (i.e., terminating impedance matches the characteristic impedance of the cable). The diagram in Figure 12 shows the appropriate external components to interface to the cable for a single transmit/receive channel. The component values are summarized in Table 19, based on the specific application. EQUIPMENT INTERFACE RECEIVE DATA TRANSFORMER ZEQ RR CC RP RR RTIP RS RRING 1:N DEVICE (1 CHANNEL) TRANSMIT DATA RT TTIP RL RT TRING N:1 5-3693(C).dr.1 Figure 12. External Line Termination Circuitry Table 19. Termination Components by Application* Symbol Name CEPT 75 CC RP RR RS ZEQ RT RL N Center Tap Capacitor Receive Primary Impedance Receive Series Impedance Receive Secondary Impedance Equivalent Line Termination Tolerance Transmit Series Impedance Transmit Load Termination Transformer Turns Ratio Unit Cable Type Coaxial Option 1 Option 2 CEPT 120 Twisted Pair 0.1 200 28.7 82.5 75 4 26.1 75 1.08 0.1 200 59 102 75 4 15.4 75 1.36 0.1 200 174 205 120 4 26.1 120 1.36 F % -- * Resistor tolerances are 1%. Transformer turns ratio tolerances are 2%. For CEPT 75 applications, Option 1 is recommended over Option 2 for lower device power dissipation. Table 24 shows the power for Option 1; Option 2 increases power dissipation by 13 mW per channel when driving 50% 1s data. Option 2 allows for the same transformer as used in CEPT 120 applications. A 5% tolerance is allowed for the transmit load termination. 32 Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Absolute Maximum Ratings Stresses in excess of the absolute maximum ratings can cause permanent or latent damage to the device. These are absolute stress ratings only. Functional operation of the device is not implied at these or any other conditions in excess of those given in the operational sections of this device specification. Exposure to absolute maximum ratings for extended periods can adversely affect device reliability. Table 20. Absolute Maximum Ratings Parameter Min Max Unit dc Supply Voltage Storage Temperature Maximum Voltage (digital pins) with Respect to VDDD Minimum Voltage (digital pins) with Respect to GNDD Maximum Allowable Voltages (RTIP[1--4], RRING[1--4]) with Respect to VDD Minimum Allowable Voltages (RTIP[1--4], RRING[1--4]) with Respect to GND -0.5 -65 -- -0.5 -- 6.5 125 0.5 -- 0.5 V C V V V -0.5 -- V Handling Precautions Although protection circuitry has been designed into this device, proper precautions should be taken to avoid exposure to electrostatic discharge (ESD) during handling and mounting. Lucent Technologies employs a human-body model (HBM) and charged-device model (CDM) for ESD-susceptibility testing and protection design evaluation. ESD voltage thresholds are dependent on the circuit parameters used in the defined model. No industry-wide standard has been adopted for the CDM. However, a standard HBM (resistance = 1500 , capacitance = 100 pF) is widely used and, therefore, can be used for comparison purposes. The HBM ESD threshold presented here was obtained by using these circuit parameters. Table 21. HBM ESD Threshold Voltage Device Voltage T7688 >1500 V Table 22. CDM ESD Threshold Voltage Device Voltage T7688 >1500 V Operating Conditions Table 23. Recommended Operating Conditions Parameter Ambient Temperature Power Supply Lucent Technologies Inc. Symbol Min Typ Max Unit TA VDD -40 4.75 -- 5.0 85 5.25 C V 33 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Operating Conditions (continued) Table 24. Power Specifications (VDD = 5 V and TA = 25 C) Device power specification includes power to the line for a specified data ones density. Parameter Per Channel*: CDR = 0, JAx = 0 (transmit, receiver in data slicing mode, no jitter attenuator) CDR = 1, JAx = 0 (transmit, receiver in clock recovery mode, no jitter attenuator) CDR = 1, JAx = 1 (transmit, receiver in clock recovery mode, jitter attenuator active) During Powerdown Mode (PWRDN = 1) Quad Total: Typical Max T7688 Unit 85 mW 106 mW 109 mW 2.5 mW 450 760 mW mW * A single channel (receive and transmit paths) for 50% 1s density data. For standby purposes. If a channel will never be used, connecting all VDD pins to the ground plane is recommended, resulting in no power consumption. For nominal VDD, TA = 25 C. Every function and channel operational with 50% 1s density. For VDD = 5.25 V and TA = 25 C. Every function and channel operational with 100% 1s density. Timing Characteristics Table 25. Logic Interface Characteristics An internal 50 k pull-up is provided on the ICT and RESET pins. An internal 100 k pull-up is provided on the CS, XCLK, and BCLK pins. This requires these input pins to sink no more than 20 A. All buffers use CMOS levels. Parameter Symbol Input Voltage: Low High Input Leakage Output Voltage: Low High Input Capacitance Load Capacitance* Test Conditions Min Max Unit 1.0 VDDD 1.0 V V A 0.5 VDDD 3.0 50 V V pF pF -- VIL VIH IL -- GNDD VDDD - 1.0 -- VOL VOH CI CL -5.0 mA 5.0 mA -- -- GNDD VDDD - 1.0 -- -- * 100 pF allowed for AD[7:0] (pins 69 to 76). 34 Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Timing Characteristics (continued) Table 26. Interface Data Timing The digital system interface timing is shown in Figure 13 for ACM = 0. If ACM = 1, then the RCLK signal in Figure 13 will be inverted. Symbol tTCLTCL tTDC tTDVTCL tTCLTDX tTCH1TCH2 tTCL2TCL1 tRCHRCL tRDVRCH tRCHRDX tRCLRDV Parameter Average TCLK Clock Period: CEPT TCLK Duty Cycle* TCLK Minimum High/Low Time Transmit Data Setup Time Transmit Data Hold Time Clock Rise Time (10%/90%) Clock Fall Time (90%/10%) RCLK Duty Cycle Receive Data Setup Time Receive Data Hold Time Receive Propagation Delay Min Typ Max Unit -- 30 100 50 40 -- -- 45 140 180 -- 488.0 -- -- -- -- -- -- 50 -- -- -- -- 70 -- -- -- 40 40 55 -- -- 40 ns % ns ns ns ns ns % ns ns ns * Refers to each individual bit period for JAT = 0 applications. Refers to each individual bit period for JAT = 1 applications using a gapped TCLK. tTCLTCL tTCH1TCH2 TCLK tTDVTCL tTCLTDX tTCL2TCL1 TPDATA OR TNDATA tRCLRDV RCLK* tRDVRCH tRCHRDX RPDATA OR RNDATA 5-1156(C)r.8 * Invert RCLK for ACM = 1. Figure 13. Interface Data Timing (ACM = 0) Lucent Technologies Inc. 35 Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Outline Diagram 100-Pin BQFP Dimensions are in millimeters. 22.860 0.305 22.350 0.255 19.050 0.405 13 1 89 14 88 PIN #1 IDENTIFIER ZONE EDGE CHAMFER 22.350 0.255 19.050 0.405 38 22.860 0.305 64 39 63 DETAIL A DETAIL B 4.570 MAX 3.555 0.255 SEATING PLANE 0.10 0.760 0.255 0.635 TYP 0.255 0.175 0.025 GAGE PLANE 0.280 0.075 SEATING PLANE 0.91/1.17 DETAIL A 36 0.150 DETAIL B M 5-1970(C).r10 Lucent Technologies Inc. Data Sheet May 1998 T7688 5.0 V E1/CEPT Quad Line Interface Ordering Information Device Code T-7688 - - - FL - DB Package 100-Pin BQFP Temperature -40 C to +85 C Comcode (Ordering Number) 107579617 DS98-231TIC Replaces DS96-172TIC to Incorporate the Following Updates 1. Title corrected. 2. Page 3, Figure 1, corrected Block Diagram (Single Channel). 3. Page 24, Table 14, Global Control Register (0100), added register address in table title. 4. Page 24, Table 15, Global Control Register (0101), added register address in table title. 5. Page 25, Channel Configuration Register Overview (0110--1001), corrected register address in section heading. 6. Page 32, Figure 12, External Line Termination Circuitry, updated transformer. Lucent Technologies Inc. 37 T7688 5.0 V E1/CEPT Quad Line Interface Data Sheet May 1998 For additional information, contact your Microelectronics Group Account Manager or the following: INTERNET: http://www.lucent.com/micro E-MAIL: docmaster@micro.lucent.com N. AMERICA: Microelectronics Group, Lucent Technologies Inc., 555 Union Boulevard, Room 30L-15P-BA, Allentown, PA 18103 1-800-372-2447, FAX 610-712-4106 (In CANADA: 1-800-553-2448, FAX 610-712-4106) ASIA PACIFIC: Microelectronics Group, Lucent Technologies Singapore Pte. Ltd., 77 Science Park Drive, #03-18 Cintech III, Singapore 118256 Tel. (65) 778 8833, FAX (65) 777 7495 CHINA: Microelectronics Group, Lucent Technologies (China) Co., Ltd., A-F2, 23/F, Zao Fong Universe Building, 1800 Zhong Shan Xi Road, Shanghai 200233 P. R. China Tel. (86) 21 6440 0468, ext. 316, FAX (86) 21 6440 0652 JAPAN: Microelectronics Group, Lucent Technologies Japan Ltd., 7-18, Higashi-Gotanda 2-chome, Shinagawa-ku, Tokyo 141, Japan Tel. (81) 3 5421 1600, FAX (81) 3 5421 1700 EUROPE: Data Requests: MICROELECTRONICS GROUP DATALINE: Tel. (44) 1189 324 299, FAX (44) 1189 328 148 Technical Inquiries: GERMANY: (49) 89 95086 0 (Munich), UNITED KINGDOM: (44) 1344 865 900 (Bracknell), FRANCE: (33) 1 41 45 77 00 (Paris), SWEDEN: (46) 8 600 7070 (Stockholm), FINLAND: (358) 9 4354 2800 (Helsinki), ITALY: (39) 2 6608131 (Milan), SPAIN: (34) 1 807 1441 (Madrid) Lucent Technologies Inc. reserves the right to make changes to the product(s) or information contained herein without notice. No liability is assumed as a result of their use or application. No rights under any patent accompany the sale of any such product(s) or information. Copyright (c) 1998 Lucent Technologies Inc. All Rights Reserved Printed in U.S.A. May 1998 DS98-231TIC (Replaces DS96-172TIC)