DS3171N+ Maxim Integrated Products, DS3171N+ Datasheet - Page 104

• Manufacturer Part Number: DS3171N+
• Description: TXRX SGL DS3/E3 400PBGA
• Manufacturer: Maxim Integrated Products

Specifications of DS3171N+

• Function: Single-Chip Transceiver
• Interface: DS3, E3
• Number Of Circuits: 1
• Voltage - Supply: 3.135 V ~ 3.465 V
• Current - Supply: 273mA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 400-BGA
• Includes: DS3 Framers, E3 Framers, HDLC Controller, On-Chip BERTs
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power (watts): -
• Other names: 90-31710+N00

10.10 Line Encoder/Decoder
10.10.1 General Description
The B3ZS/HDB3 Decoder converts a bipolar signal to a unipolar signal in the receive direction. B3ZS/HDB3
Encoder converts a unipolar signal to a bipolar signal in the transmit direction.
In the transmit direction, the Encoder converts the unipolar signal to a bipolar signal, optionally performing zero
suppression encoding (HDB3/B3ZS), optionally inserting errors, and outputs the bipolar signal.
In the receive direction, the Decoder receives a bipolar signal, monitors it for alarms and errors, optionally
performing zero suppression decoding (HDB3/B3ZS), and converts it to a unipolar signal.
If the port line interface is configured for a Unipolar mode, the BPV detector will count pulses on the RLCVn pin.
See
Figure 10-25. Line Encoder/Decoder Block Diagram
10.10.2 Features
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10.10.3 B3ZS/HDB3 Encoder
B3ZS/HDB3 Encoder performs unipolar to bipolar conversion and zero suppression encoding.
Unipolar to bipolar conversion converts the unipolar data stream into an AMI bipolar data stream (POS and NEG).
In an AMI bipolar data stream a zero is represented by a zero on both the POS and NEG signals, and a one is
represented by a one on a bipolar signal (POS or NEG), and a zero on the other bipolar signal (NEG or POS).
Successive ones are represented by ones that are alternately output on the POS and NEG signals. i.e., if a one is
represented by a one on POS and a zero on NEG, the next one will be represented by a one on NEG and a zero
on POS.
Zero suppression encoding converts an AMI bipolar data stream into a B3ZS or HDB3 encoded bipolar data
stream. A B3ZS encoded bipolar signal is generated by inserting a B3ZS signature into the bipolar data stream if
both the POS and NEG signals are zero for three consecutive clock periods. An HDB3 encoded bipolar signal is
Clock Rate
Performs bipolar to unipolar encoding and decoding – Converts a unipolar signal into an AMI bipolar signal
(POS data, and NEG data) and vice versa.
Programmable zero suppression – B3ZS or HDB3 zero suppression encoding and decoding can be
performed, or the bipolar data stream can be left as an AMI encoded data stream.
Programmable receive zero suppression code format – The signature of B3ZS or HDB3 is selectable.
Generates and detects alarms and errors – In the receive direction, detects LOS alarm condition BPV
errors, and EXZ errors. In the transmit direction, errors can be inserted into the outgoing data stream.
Receive
Transmit
DS3/E3
Figure 10-25
DS3/E3
Adapter
LIU
LIU
for the locations of the Line Encoder/ Decoder block in the DS317x devices.
Encoder
Decoder
B3ZS/
HDB3
HDB3
B3ZS/
TUA1
TAIS
IEEE P1149.1
Access Port
JTAG Test
FEAC
DS3 / E3
DS3 / E3
Receive
Framer
Transmit
Formatter
Buffer
Trace
Trail
HDLC
GEN
UA1
104
RX BERT
TX BERT
Microprocessor
Interface