ETC 78P2244

78P2244
Quad E3/DS3/STS-1
Transceiver
Advanced Product Notice
June 2000
DESCRIPTION
FEATURES
The 78P2244 is a quad channel version of the
78P2241. Each of the four channels is a complete line
interface transceiver for E3, DS3, STS-1, North
America T3 and ATM applications. Each channel
includes clock recovery and transmitter pulse shaping
functions for applications using 75-ohm coaxial cable
at distances up to 1100 feet. These applications
include DSLAMs, T3/E3 digital multiplexers, SONET
Add/Drop multiplexers, PDH equipment, DS3 to Fiber
optic and microwave modems and ATM WAN access
for routers and switches.
Each receiver recovers clock and data from a B3ZS or
HDB3-coded AMI signal. The receiver can compensate
for over 12dB of cable and 6dB of flat loss. Each
transmitter has the B3ZS/HDB3 ENDEC with a receive
line code violation detector, a loop-back mode, a clock
polarity selection mode, and the ability to receive a
DSX3 monitor signal. Signals generated meet the
standard pulse shape requirements.
The 78P2244 is manufactured in an advanced
BiCMOS process and operates at both 3.3V and
5V power supply voltages.
•
Quad channel transmit and receive interface
for E3, DS3 and STS-1 applications
•
Interfaces to 75 ohm coaxial cable over 1100
feet at speeds up to 51.84 Mbit/s
•
Compliant with ANSI T1.102-1993, Telcordia
GR-499-CORE and GR-253-CORE, ITU-T G.703,
G.823 and G.824 for jitter tolerance and G.775
for loss of signal
•
Compliant with ATM FORUM af-phy-0034 (E3
public UNI) and af-phy-0054 (DS3 public UNI)
•
Easily Interfaced to ATM framer ICs such as
PMC-Sierra 7345 , and 7346 QJET
•
Receive DS3-high and DSX3 monitor signals
•
Diagnostic loop-back for AMI and digital signals
•
Selectable B3ZS/HDB3 ENDEC
•
Receive Line Code Violation Detector
•
128-lead TQFP package
•
3.3V or 5V operation
•
Input circuit works transformer or AC coupled
TXEN
Signal from
Adjacent Port
LBO
DLPBK
BLOCK DIAGRAM
ENDEC
TPOS/TNRZ
TNEG
TCLK
B3ZS/
HDB3
Encoder
PULSE
SHAPER
LOUTP
LOUTN
ENDEC
RPOS/RNRZ
RNEG/RLCV
B3ZS/
HDB3
Decoder
RCLK
Data
Slicer
Adaptiv e
Equalizer
LINP
LINN
Clock
Reco ver y
Signal
Detector
MON
LOS
RXLPBK
Biasing
LF
PWDN
Port 1
Port 2
Port 3
Port 4
78P2244
Quad E3/DS3/STS-1
Transceiver
FUNCTIONAL DESCRIPTION
The decoder also detects Receive Line Code
Violations (RLCV) and outputs a pulse via the
RNEG/RLCV pin. Three different classes of line
code violations are detected.
The 78P2244 contains all the necessary transmit and
receive circuitry for connection between E3, DS3, or
STS-1 signals and digital Framer/Deframer ICs.
Operating Rate
The DS3 and E3 pins determine which mode the
chip operates in according to the table below. They
control the PLL center frequency, the equalizer
response, the transmitter pulse shape, and the
transmitter amplitude.
1)
Too many zeros:
More than two (three)
consecutive zeros in B3ZS (HDB3) mode.
2)
Not enough zeros between bipolar pulse (B)
and bipolar violation pulse (V): (B,V) for B3ZS.
(B,V) or (B,0,V) for HDB3.
3)
Standard
E3
DS3
STS-1
STS-1
DS3 PIN
Low
High
Low
High
E3 PIN
High
Low
Low
High
On the transmit side, when the ENDEC pin is low,
NRZ input data is encoded to Positive and Negative
logic data following the B3ZS (for DS3/STS-1) or
HDB3 (for E3) substitution codes. The NRZ data is
input to the TPOS/TNRZ pin as shown below.
B3ZS/HDB3 ENDEC WITH LINE CODE
VIOLATION DETECT
The 78P2244 includes a selectable B3ZS/HDB3
Encoder/Decoder (ENDEC). When the ENDEC pin
is low, the ENDEC is selected and the decoder
generates a composite NRZ logic data stream
following the B3ZS (for DS3/STS-1) or HDB3 (for E3)
substitution codes via the RPOS/RNRZ pin as
shown below.
ENDEC
RPOS/RNRZ
RNEG/RLCV
High
Low
Positive AMI
NRZ data
Negative AMI
Receive Line Code
Violation Indicator
Code violation: Even number of bipolar pulses
(B) detected between bipolar violation pulses (V).
ENDEC
TPOS/TNRZ
TNEG
High
Low
Positive AMI
NRZ data
Negative AMI
No Connect
No responsibility is assumed by TDK Semiconductor Corporation for use of this product nor for any infringements of patents and trademarks
or other rights of third parties resulting from its use. No license is granted under any patents, patent rights or trademarks of TDK
Semiconductor Corporation and the company reserves the right to make changes in specifications at any time without notice. Accordingly, the
reader is cautioned to verify that the data sheet is current before placing orders.
TDK Semiconductor Corporation, 2642 Michelle Drive, Tustin, CA 92780-7019, (714) 508-8800, FAX: (714) 508-8877
2000 TDK Semiconductor Corporation
06/06/00- rev. A
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