Rainbow Electronics DS3150 User Manual
Y
K
K
STS
t
STS
www.maxim-ic.com
FEATURES
Integrated transmit and receive for T3, E3,
and STS-1 line interfaces
Performs clock/data recovery and wave
shaping
Requires no special external components
other than 1:2 transformers
Interfaces to 75Ω coaxial cable at lengths up
to 380m (T3), 440m (E3), or 360m (STS-1)
Adaptive receive equalizer handles from 0dB
to 15dB of cable loss
Interfaces directly to a DSX monitor signal
(20dB flat loss)
On-chip jitter attenuator can be placed either
in the receive path or the transmit path
Built-in B3ZS and HDB3 coder/decoder
Bipolar and NRZ interfaces
Analog and digital loopbacks
Onboard 215 - 1 and 223 - 1 Pseudo Random
Bit Sequence (PRBS) generator and detector
Transmit line-driver monitor checks for a
faulty transmitter or a shorted output
Complete T3 AIS generator (ANSI T1.107)
Unframed all ones generator (E3 AIS)
Digital clock inversion capability
Three-state line driver for low-power mode
Loss-of-signal detector (ANSI T1.231-1999
and ITU G.775)
Pin compatible with the TDK 78P7200 and
78P7200L
Drop-in replacement for TDK 78P2241/B
(Refer to Application Note 362)
Low-power 3.3V operation (5V tolerant I/O)
Industrial temperature range: -40°C to +85°C
Small packaging: 28-pin PLCC and
48-pin TQFP
PRELIMINARY
PRELIMINAR
DS3150
3.3V T3/E3/STS-1 Line Interface Unit
FUNCTIONAL DIAGRAM
Line In
T3, E3,
-1
Rx+
Rx-
Line Ou
T3, E3,
-1
Tx+
Tx-
DS3150 LIU
ORDERING INFORMATION
DS3150QN 28-Pin PLCC -40°C to +85°C
DS3150Q 28-Pin PLCC 0°C to +70°C
DS3150TN 48-Pin TQFP -40°C to +85°C
DS3150T 48-Pin TQFP 0°C to +70°C
RCL
RPOS
RNE
TCL
TPOS
TNEG
Receive
Clock and
Data
Transmit
Clock and
Data
Note: Some revisions of this device may incorporate deviations from published specifications known
as errata. Multiple revisions of any device may be simultaneously available through various sales
channels. For information about device errata, click here: http://dbserv.maxim-ic.com/errata.cfm
1 of 22 020602
.
TABLE OF CONTENTS
1. FUNCTIONAL DESCRIPTION ……………………………………………………………..3
2. SIGNAL DESCRIPTION……………………………………………………………………13
3. AC CHARACTERISTICS …………………………...………………...……………………17
4. PIN ASSIGNMENTS ………………………………………………………………………19
5. MECHANICAL DIMENSIONS ………………...……………...…………………………..20
6. APPLICATIONS……………..……………………………………………………….……..22
DS3150
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DS3150
r
1. FUNCTIONAL DESCRIPTION
The DS3150 performs all the functions necessary for interfacing at the physical layer to T3, E3, and STS1 lines. The device has independent receive and transmit paths (Figure 1A). The receiver performs clock
and data recovery from a B3ZS-code or HDB3-code AMI signal and monitors for loss of the incoming
signal. The recovered data optionally can be B3ZS/HDB3 decoded and output in NRZ format. The
transmitter accepts either NRZ or bipolar data and drives standard pulse-shape waveforms onto 75!
coaxial cable. The receiver and transmitter sections will be discussed separately below. Table 1A lists the
telecommunications standards that the DS3150 was designed to meet.
Figure 1A. DS3150 BLOCK DIAGRAM
RX+
RX-
DM*
TX+
TX-
liu_bd
RMON
20dB
Flat
Gain
Analog
Loopback
Driver
Monitor
Line
Driver
Loopback Control
Filter/
Equalizer
(Analog
Loss Of
Signal
Detect)
Squelch
WaveShaping
Clock &
Data
Recovery
Jitter Attenuato
Power
Connections
LOS*MCLK
Output Decode
Digital Loss Of
Signal Detector
B3ZS/HDB3
Decoder
Remote
Loopback
Mux
(can be placed in either the receive path or the transmit path)
B3ZS/
HDB3
Encoder
Test Functions
Mux
PRBS
Detector
mux
AIS/
1010.../
PRBS
Generation
Clock
Invert
Clock
Invert
PRBS
RPOS/RNRZ
RNEG/RLCV
RCLK
ZCSE*
ICE
TESS
TNEG
TPOS/TNRZ
TCLK
TTS*
LBKS*
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LBO
V
DD
SS
EFEV
TDS0 TDS1
DS3150
Table 1A. APPLICABLE STANDARDS
T1.102-1993 (ANSI) “Digital Hierarchy–Electrical Interfaces”
T1.107-1995 (ANSI) “Digital Hierarchy–Formats Specification”
T1.231-1997 (ANSI) Draft “Digital Hierarchy–Layer 1 In-Service Digital Transmission
Performance Monitoring”
T1.231-1993 (ANSI) “Digital Hierarchy–Layer 1 In-Service Digital Transmission Performance
Monitoring”
T1.404-1994 (ANSI) “Network-to-Customer Installation–DS3 Metallic Interface Specification”
GR-499-CORE (Bellcore) Issue 1, December 1995 “Transport Systems Generic Requirements
(TSGR): Common Requirements”
GR-253-CORE (Bellcore) Issue 2, December 1995 “SONET Transport Systems: Common Generic
Criteria”
G.703, 1991 (ITU) “Physical/Electrical Characteristics of Hierarchical Digital Interfaces
G.751, 1993 (ITU) “Digital Multiplex Equipment Operating at the Third Order Bit Rate of
34,368kbit(s) and the Fourth Order Bit Rate of 139,264kbit(s) and Using Postive
Justification”
G.823, 1993 (ITU) “The Control of Jitter and Wander Within Digital Networks that are based
on the 2048kbit(s) Hierarchy”
G.775, 1994 (ITU) “Loss of Signal (LOS) and Alarm Indication Signal (AIS) Defect Detection
and Clearance Criteria”
O.151, 1992 (ITU) “Error Performance Measuring Equipment Operating at the Primary Rate
and Above”
TBR 24, 1997 (ETSI) “Business TeleCommunications; 34Mbit(s) digital unstructured and
structured lease lines; attachment requirements for terminal equipment interface
ETS 300 687, 1996 (ETSI) “Business TeleCommunications; 34Mbit(s) digital leased lines (D34U and
D34S); Connection characteristics
ETS 300 686, 1996 (ETSI) “Business TeleCommunications; 34Mbit(s) and 140Mbits(s) digital leased
lines (D34U, D34S, D140U, and D140S); Network interface presentation
Figure 1B. EXTERNAL CONNECTION
Transmit
V
Receive
1:2ct
1:2ct
VDD
0.05µF
0.05µF
330Ω
(1%)
330Ω
(1%)
TX+
TX-
DS3150
RX+
RX-
DD
V
DD
0.01µF
0.01µF
0.1µF
0.1µF
1µF
1µF
3.3V
Power
Plane
V
DD
V
SS
V
SS
0.01µF
0.1µF
1µF
Ground
Plane
V
SS
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DS3150
Table 1B. DS3150 T3/E3/STS-1 LIU TRANSFORMER RECOMMENDATIONS
MANUFACTURER
Pulse Engineering
Pulse Engineering
Halo Electronics
Halo Electronics
Note: Table subject to change. Commercial Temp: 0°C to +70°C
PART
NO.
PE-
65968
PE-
65969
TG07-
0206NS
TD07-
0206NE
TURNS
RATIO
1:2CT LS-1/C 6-pin SMT 19 0.06 0.250 to 500
1:2CT LC-1/C 6-pin thru-hole 19 0.06 0.250 to 500
1:2CT SMD/B 6-pin SMT 19 0.06 0.250 to 500
1:2CT DIP/B 6-pin DIP 19 0.06 0.250 to 500
PKG/
SCHEMATIC
DESCRIPTION
OCL
PRIMARY
µµµµH
BANDWIDTH
L
L
µµµµH
75ΩΩΩΩ (MHz)
RECEIVER
The DS3150 interfaces to the receive T3/E3/STS-1 coax line through a 1:2 step-up transformer
(Figure 1B). The receiver automaticall y adapts to coax cable loses from 0d B to 15dB, which translates
into 0m to 380m (T3) or 440m (E3) or 360m (STS-1) of coax cable (AT&T 734A or equivalent). The
receiver also has the ability to interface to monitor jacks. Through the RMON input (Table 2A), the
device can be configured to insert a 20dB flat boost into the incoming signal. Monitor jacks typically
have series resistors that result in a resistive loss of 20dB. The receiver has excellent jitter tolerance
characteristics (Figure 1C).
The receiver contains bot h analog and digital loss-of-signal (LOS) detect ors. The analog LOS detector
resides in the equalizer. If the incoming signal drops below -24dB of the nominal signal level, the a nalog
LOS detector will activate and it will step on the recovered data and force all zeros out of the data
recovery circuitry. The analog LOS detector will not clear until the signal level is above
-18dB of the nominal signal level. The digital LOS detector is activated when it detects 192±1
consecutive zeros. LOS is clear ed when there are no excessive zero occurrences ove r a span of 192±1
clock periods. An excessive zero occurrence is defined as t hree or more consecutive zeros in the T3 and
STS-1 modes and four or more zeros in the E3 mode. The status of the digital LOS is reflected at the
LOS* output (Table 2A). There is no status output available for the analog LOS detector. While the
device is in a LOS state, the RCLK output will be referenced to the MCLK input (or the TC LK input if
MCLK is high/floating or to the internal oscillator if MCLK is tied low). The analog LOS detector has a
longer time constant than the digital LOS. Hence, when the incoming signal is lost, the digital LOS will
activate first followed by the analog LOS detector. When a signal is restored, the digital LOS will not be
allowed to qualify a signal for no excessive zero violations until the analog LOS detector has seen the
signal rise above -18dB. Governing specifications for the LOS detectors are ANSI T1.231 and ITU
G.775.
The recovered data from the receiver can be output in either bipolar format or nonreturn-to -zero (NRZ)
format. To select the bipolar format, the ZCSE* input is tied high. In this format, the B3ZS/HDB3
decoder is disabled and the received data is buffered and then output on the RPOS and RNEG outputs. To
select the NRZ format, the ZCSE* input is tied low. In this format, the B3ZS/HBD3 decoder is enabled
and the recovered data is B3ZS/HDB3 decoded and then logicall y OR’ed together at the RNRZ output,
while the RLCV output indicates line code violations.
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Figure 1C. RECEIVER JITTER TOLERANCE
J
(U
p
p
)
T3 [GR-499 (1995)]
10
l
1.0
Category II
T3 [GR-499 (1995)]
Category I
E3 [G.823(1993)]
10
5
1.5
DS3150
Jitter
Tolerance
DS3150
itter Tolerance
0.1
0.3
0.15
0.1
10 100 1k 10k 100k 1M
60k22.3k2.3k669
300k 800k
Frequency (Hz)
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DS3150
TRANSMITTER
Through the ZCSE* input, the device is configured to accept either bipolar data or NRZ data to be input
to the transmitter. When the ZCSE* input is tied high, bipolar data must be applied at the TPOS and
TNEG inputs. In this mode, the device will not perform B3ZS/HDB3-encoding on the outgoing data
stream. When the ZCSE* input is tied low, an NRZ data stream must be applied at the TPOS input
(TNEG is ignored). In this mode, the device will perform B3ZS/HDB3-encoding on the outgoing data
stream.
The clock applied at the TCLK input is used to transmit data onto the T3/E3/STS-1 line. Hence, TCLK
must be of transmission quality (i.e., accurate to ±20ppm). The duty cycle of TCLK is not a key
parameter as long as the clock high and low times listed in Section 3 are met.
The DS3150 also has the ability to generate a number of different patterns, including an unframed all
ones pattern, which is also the E3 AIS signal; a 101010… pattern; or a T3 Alarm Indication Signal (AIS).
See Figure 1E for a description of the T3 AIS. The TDS0 and TDS1 inputs are used to select these
onboard patterns (Tables 2A and 2B).
The DS3150 interfaces to the transmit T3/E3/STS-1 coax cable through a 1:2 step up transformer (Figure
1B). It will drive the 75! cable and create the proper waveforms required for interfacing to T3/E3/STS-1
lines. In T3 and STS-1 modes, the LBO (line build out) pin controls waveform shape. For cable lengths
fewer than 225ft, LBO should be pulled high. For 225ft or more of cable, LBO should be pulled low.
Tables 1C through 1G and Figure 1D detail the waveform template specifications and testing parameters.
The transmitter can be disabled and the Tx+ and Tx- outputs three-stated through the TTS* input (Table
2A).
The transmit driver monitor constantly checks the analog signal output at Tx+ and Tx-. If the output fails,
then the DM* output will be pulled low. When the transmitter is disabled (TTS* = 0), the driver monitor
is also disabled.
Table 1C. T3 TRANSMIT WAVEFORM TEMPLATE
TIME AXIS RANGE NORMALIZED AMPLITUDE EQUATIONS
Upper
Curve
-0.85 ≤ T ≤ -0.68
-0.68 ≤ T ≤ 0.36 0.5 {1 + sin[(π / 2)(1 + T / 0.34)]} + 0.03
0.36 ≤ T ≤ 1.4
Lower
Curve
-0.85 ≤ T ≤ -0.36
-0.36 ≤ T ≤ 0.36 0.5 {1 + sin[(π/2)(1 + T/0.18)]} - 0.03
0.36 ≤ T ≤ 1.4
Governing Specifications: ANSI T1.102-1993 and Bellcore GR-499
0.03
0.08 + 0.407e
-0.03
-0.03
-1.84(T - 0.36)
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