DS26303G-120 MAXIM [Maxim Integrated Products], DS26303G-120 Datasheet - Page 54

• Manufacturer Part Number: DS26303G-120
• Description: 3.3V, E1/T1/J1, Short-Haul, Octal Line Interface Unit
• Manufacturer: MAXIM [Maxim Integrated Products]

6.3 Transmitter
NRZ data arrives on TPOS and TNEG on the transmit system side. The TPOS and TNEG data is sampled on the
falling edge of TCLK
The data is encoded with HDB3 or B8ZS or NRZ encoding when single-rail mode is selected (only TPOS as the
data source). When in single-rail mode only, BPV errors can be inserted for test purposes by register BEIR.
Preencoded data is expected when dual-rail mode is selected. The encoded data passes through a jitter attenuator
if it is enabled for the transmit path. A digital sequencer and DAC generate transmit waveforms compliant with
T1.102 and G.703 pulse masks.
A line driver drives an internal matched-impedance circuit for provision of 100W, 110W, 120W, and 75W termination.
The DS26303 drivers have short-circuit driver-fail-monitor detection. There is an OE pin that can high-Z the
transmitter outputs for protection switching. The individual transmitters can be placed in high impedance by register
OEB.
the transmitter operation are shown in
Table 6-1. Telecommunications Specification Compliance for DS26303 Transmitters
Table 6-2. Registers Related to Control of DS26303 Transmitters
Driver Fault Monitor Interrupt Enable
Driver Fault Monitor Interrupt Status
Individual Short-Circuit-Protection
Single-Rail Mode Select Register
AMI Coding, B8ZS Substitution, DS1 Electrical
Global Configuration Register
Template Select Transmitter
Output Enable Configuration
Transmission and Return Loss Compliance
Driver Fault Monitor Status
Transmit All-Ones Enable
Transmit Electrical Characteristics for E1
The DS26303 also has functionality for powering down the transmitters individually. The registers that control
Master Clock Selection
BERT Control Register
Transmit Power-Down
T1 Telecom Pulse Mask Compliance
T1 Telecom Pulse Mask Compliance
Line Code Selection
REGISTER NAME
Template Select
TRANSMITTER FUNCTION
Register
Disable
(Figure
Interface
10-12).
Table 6-3.
ACRONYM
DFMIE
DFMIS
ISCPD
SRMS
TAOE
DFMS
BTCR
TPDE
OEB
TST
LCS
MC
GC
TS
DS26303: 3.3V, T1/E1/J1, Short-Haul, Octal Line Interface Unit
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Transmit All-Ones Enable.
Driver Fault Status.
Driver Fault Status Interrupt Mask.
Driver Fault Status Interrupt Mask.
Selection of the jitter attenuator in the transmit receive or not
used and code for B8ZS or HDB3 substitution.
The transmitter that the template select applies to.
The TS2 to TS0 bits for selection of the templates for
transmitter and match impedance for the receiver.
This bits can be used to place the transmitter outputs in high-
impedance mode.
Selects the MCLK frequency used for transmit and receive.
This register can be used to select between single-rail and
dual-rail mode.
The individual LIU line codes can be selected to overwrite
the global setting.
Individual transmitters can be powered down.
This register allows the individual transmitters short-circuit
protection disable.
This register is used for sending different BERT patterns for
the individual transmitters.
TELECOMMUNICATIONS COMPLIANCE
ANSI T1.102
ANSI T1.403
ANSI T1.102
ITUT G.703
FUNCTION