ETC LXT384LE

LXT384
Octal T1/E1/J1 Line Interface Unit
Datasheet
The LXT384 is an octal short haul Pulse Code Modulation (PCM) Line Interface Unit for use in
both 1.544 Mbps (T1) and 2.048 Mbps (E1) applications. It incorporates eight independent
receivers and eight independent transmitters in a single 144 pin LQFP or 160 ball PBGA
package.
The LXT384 transmits shaped waveforms meeting G.703 and T1.102 specifications. The
transmit drivers provide low impedance independent of the transmit pattern and supply voltage
variations. The LXT384 exceeds the latest transmit return loss specifications, such as ETSI ETS300166. All transmitters include a power down mode with fast output tristate capability.
The LXT384’s differential receiver architecture provides high noise interference margin and is
able to work with up to 12 dB of cable attenuation. The optional digital clock recovery PLL and
jitter attenuator are referenced to a low frequency 1.544 MHz or 2.048 MHz clock.
The LXT384 incorporates an advanced crystal-less jitter attenuator switchable between the
receive and transmit path. The jitter attenuation performance meets the latest international
specifications such as CTR12/13. The jitter attenuation performance was optimized for
Sychronous Optical NETwork/Sychronous Digital Hierarchy (SONET/SDH) applications.
The LXT384 can be configured as a 7 channel transceiver with G.772 compliant non intrusive
protected monitoring points.
The LXT384 includes Hitless Protection Switching (HPS) feature which helps increase quality
of service and eliminates relays in redundancy and 1+1 protection applications. Fast tristate-able
drivers and a constant delay jitter attenuator are critical to achieving HPS.
Product Features
■
■
■
■
Single rail 3.3V supply with 5V tolerant
inputs
Low power consumption of 130mW per
channel (typ.)
Superior crystal-less jitter attenuator
— Meets ETSI CTR12/13, ITU G.736,
G.742, G.823 and AT&T Pub 62411
specifications
— Optimized for SONET/SDH
applications, meets ITU G.783 mapping
jitter specification
— Constant throughput delay jitter
attenuator
Hitless Protection Switching (HPS) for 1 to
1 protection without relays
■
■
■
■
■
■
■
■
■
Transmit return loss exceeds ETSI ETS
300166
HDB3, B8ZS, or AMI line encoder/decoder
Provides protected monitoring points per
ITU G.772
Analog/digital and remote loopback testing
functions
LOS per ITU G.775, ETS 300 233 and
T1.231
8 bit parallel or 4 wire serial control
interface
Hardware and Software control modes
JTAG Boundary Scan test port per IEEE
1149.1
144 pin LQFP and 160 ball PBGA
packages
As of January 15, 2001, this document replaces the Level One document
known as Octal T1/E1 Transceiver.
Order Number: 248994-001
January 2001
Information in this document is provided in connection with Intel® products. No license, express or implied, by estoppel or otherwise, to any intellectual
property rights is granted by this document. Except as provided in Intel’s Terms and Conditions of Sale for such products, Intel assumes no liability
whatsoever, and Intel disclaims any express or implied warranty, relating to sale and/or use of Intel products including liability or warranties relating to
fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right. Intel products are not
intended for use in medical, life saving, or life sustaining applications.
Intel may make changes to specifications and product descriptions at any time, without notice.
Designers must not rely on the absence or characteristics of any features or instructions marked "reserved" or "undefined." Intel reserves these for
future definition and shall have no responsibility whatsoever for conflicts or incompatibilities arising from future changes to them.
The LXT384 may contain design defects or errors known as errata which may cause the product to deviate from published specifications. Current
characterized errata are available on request.
Contact your local Intel sales office or your distributor to obtain the latest specifications and before placing your product order.
Copies of documents which have an ordering number and are referenced in this document, or other Intel literature may be obtained by calling
1-800-548-4725 or by visiting Intel’s website at http://www.intel.com.
Copyright © Intel Corporation, 2001
*Third-party brands and names are the property of their respective owners.
Datasheet
Octal T1/E1/J1 Line Interface Unit — LXT384
Contents
1.0
Pin Assignments and Signal Descriptions.......................................................................... 9
2.0
Functional Description......................................................................................................22
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
2.10
2.11
2.12
2.13
2.14
Initialization..........................................................................................................22
2.1.1 Reset Operation .....................................................................................23
Receiver ..............................................................................................................23
2.2.1 Loss of Signal Detector ..........................................................................23
2.2.1.1 E1 Mode ....................................................................................24
2.2.1.2 T1 Mode ....................................................................................24
2.2.1.3 Data Recovery Mode.................................................................24
2.2.2 Alarm Indication Signal (AIS) Detection .................................................24
2.2.2.1 E1 Mode ....................................................................................24
2.2.2.2 T1 Mode ....................................................................................25
2.2.3 Receive Alarm Indication Signal (RAIS) .................................................25
2.2.4 In Service Code Violation Monitoring .....................................................25
Transmitter ..........................................................................................................25
2.3.1 Transmit Pulse Shaping .........................................................................26
2.3.1.1 Hardware Mode .........................................................................26
2.3.1.2 Host Mode .................................................................................26
2.3.1.3 Output Driver Power Supply ......................................................27
2.3.1.4 Power Sequencing ....................................................................27
Driver Failure Monitor..........................................................................................27
Line Protection ....................................................................................................30
Jitter Attenuation .................................................................................................30
Loopbacks ...........................................................................................................31
2.7.1 Analog Loopback....................................................................................31
2.7.2 Digital Loopback.....................................................................................32
2.7.3 Remote Loopback ..................................................................................32
2.7.4 Transmit All Ones (TAOS)......................................................................32
G.772 Performance Monitoring ...........................................................................33
Hitless Protection Switching (HPS) .....................................................................34
Operation Mode Summary ..................................................................................34
Interfacing with 5V Logic .....................................................................................35
Parallel Host Interface .........................................................................................35
2.12.1 Motorola Interface ..................................................................................36
2.12.2 Intel Interface..........................................................................................36
Interrupt Handling................................................................................................36
2.13.1 Interrupt Sources....................................................................................36
2.13.2 Interrupt Enable......................................................................................37
2.13.3 Interrupt Clear ........................................................................................37
Serial Host Mode.................................................................................................37
3.0
Register Descriptions ....................................................................................................... 38
4.0
JTAG Boundary Scan.......................................................................................................45
4.1
4.2
Datasheet
Overview .............................................................................................................45
Architecture .........................................................................................................45
3
LXT384 — Octal T1/E1/J1 Line Interface Unit
4.3
4.4
5.0
Test Specifications ........................................................................................................... 54
5.1
6.0
TAP Controller..................................................................................................... 46
JTAG Register Description.................................................................................. 48
4.4.1 Boundary Scan Register (BSR).............................................................. 49
4.4.2 Analog Port Scan Register (ASR) .......................................................... 52
4.4.3 Device Identification Register (IDR) ....................................................... 53
4.4.4 Bypass Register (BYR) .......................................................................... 53
4.4.5 Instruction Register (IR) ......................................................................... 53
Recommendations and Specifications ................................................................ 76
Mechanical Specifications................................................................................................ 78
Figures
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
4
LXT384 Detailed Block Diagram ........................................................................... 7
LXT384 Detailed Block Diagram ........................................................................... 8
LXT384 Low-Profile Quad Flate Package (LQFP) 144-Pin Assignments and Package Markings9
LXT384 Plastic Ball Grid Array (PBGA) Package Pin Assignments ................... 10
50% AMI Encoding.............................................................................................. 26
External Transmit/Receive Line Circuitry ............................................................ 29
Jitter Attenuator Loop.......................................................................................... 31
Analog Loopback ................................................................................................ 31
Digital Loopback.................................................................................................. 32
Remote Loopback ............................................................................................... 32
TAOS Data Path ................................................................................................. 33
TAOS with Digital Loopback ............................................................................... 33
TAOS with Analog Loopback .............................................................................. 33
Serial Host Mode Timing..................................................................................... 38
JTAG Architecture............................................................................................... 46
JTAG State Diagram ........................................................................................... 48
Analog Test Port Application............................................................................... 53
Transmit Clock Timing Diagram.......................................................................... 61
Receive Clock Timing Diagram........................................................................... 62
JTAG Timing ....................................................................................................... 63
Non-Multiplexed Intel Mode Read Timing ........................................................... 64
Multiplexed Intel Mode Read Timing................................................................... 64
Non-Multiplexed Intel Mode Write Timing ........................................................... 66
Multiplexed Intel Mode Write Timing ................................................................... 66
Non-Multiplexed Motorola Mode Read Timing.................................................... 68
Multiplexed Motorola Mode Read Timing............................................................ 68
Non-Multiplexed Motorola Mode Write Timing .................................................... 69
Multiplexed Motorola Mode Write Timing ............................................................ 70
Serial Input Timing .............................................................................................. 71
Serial Output Timing ........................................................................................... 71
E1, G.703 Mask Templates................................................................................. 72
T1, T1.102 Mask Templates ............................................................................... 73
LXT384 Jitter Tolerance Performance ................................................................ 74
LXT384 Jitter Transfer Performance................................................................... 75
LXT384 Output Jitter for CTR12/13 Applications ................................................ 76
Datasheet
Octal T1/E1/J1 Line Interface Unit — LXT384
36
37
Low Quad Flat Packages (LQFP) Dimensions....................................................78
Plastic Ball Grid Array (PBGA) Package Dimensions .........................................79
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
LXT384 Pin Description.......................................................................................11
Line Length Equalizer Inputs...............................................................................27
Jitter Attenuation Specifications ..........................................................................30
Operation Mode Summary ..................................................................................34
Microprocessor Interface Selection .....................................................................35
Serial and Parallel Port Register Addresses .......................................................38
Register Bit Names .............................................................................................39
ID Register, ID (00h) ...........................................................................................40
Analog Loopback Register, ALOOP (01h) ..........................................................40
Remote Loopback Register, RLOOP (02h).........................................................40
TAOS Enable Register, TAOS (03h)...................................................................40
LOS Status Monitor Register, LOS (04h) ............................................................41
DFM Status Monitor Register, DFM (05h)...........................................................41
LOS Interrupt Enable Register, LIE (06h) ...........................................................41
DFM Interrupt Enable Register, DIE (07h) ..........................................................41
LOS Interrupt Status Register, LIS (08h) ............................................................41
DFM Interrupt Status Register, DIS (09h) ...........................................................41
Software Reset Register, RES (0Ah) ..................................................................42
Performance Monitoring Register, MON (0Bh) ...................................................42
Digital Loopback Register, DL (0Ch)...................................................................42
LOS/AIS Criteria Register, LCS (0Dh) ................................................................42
Automatic TAOS Select Register, ATS (0Eh) .....................................................42
Global Control Register, GCR (0Fh) ...................................................................43
Pulse Shaping Indirect Address Register, PSIAD (10h)......................................43
Pulse Shaping Data Register, PSDAT (11h).......................................................44
Output Enable Register, OER (12h)....................................................................44
AIS Status Monitor Register, AIS (13h)...............................................................44
AIS Interrupt Enable Register, AISIE (14h) .........................................................44
AIS Interrupt Status Register, AISIS (15h) ..........................................................45
TAP State Description .........................................................................................46
Boundary Scan Register (BSR)...........................................................................49
Analog Port Scan Register (ASR) .......................................................................52
Device Identification Register (IDR) ....................................................................53
Instruction Register (IR) ......................................................................................54
Absolute Maximum Ratings.................................................................................54
Recommended Operating Conditions .................................................................55
DC Characteristics ..............................................................................................55
E1 Transmit Transmission Characteristics..........................................................56
E1 Receive Transmission Characteristics...........................................................57
T1 Transmit Transmission Characteristics ..........................................................58
T1 Receive Transmission Characteristics ...........................................................58
Jitter Attenuator Characteristics ..........................................................................59
Analog Test Port Characteristics.........................................................................60
Transmit Timing Characteristics..........................................................................60
Receive Timing Characteristics...........................................................................61
Tables
Datasheet
5
LXT384 — Octal T1/E1/J1 Line Interface Unit
46
47
48
49
50
51
52
53
54
6
JTAG Timing Characteristics .............................................................................. 62
Intel Mode Read Timing Characteristics2 ........................................................... 63
Intel Mode Write Timing Characteristics2 ........................................................... 65
Motorola Bus Read Timing Characteristics2....................................................... 67
Motorola Mode Write Timing Characteristics2 .................................................... 69
Serial I/O Timing Characteristics......................................................................... 70
Transformer Specifications ................................................................................. 71
G.703 2.048 Mbit/s Pulse Mask Specifications ................................................... 72
T1.102 1.544 Mbit/s Pulse Mask Specifications.................................................. 72
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Applications
■
■
■
SONET/SDH tributary interfaces
Digital cross connects
Public/private switching trunk line
interfaces
■
■
Microwave transmission systems
M13, E1-E3 MUX
Figure 1. LXT384 Detailed Block Diagram
MODE
JTAG
SERIAL/
PARALLEL
PORT
LOOP 0..7
HARDWARE / SOFTWARE CONTROL
(JTAG INTERFACE)
JASEL
CLKE
MCLK
LOS
LOS
TRING
LINE DRIVER
PULSE
PULSE
SHAPER
JITTER
ATTENUATOR
RX OR TX
PATH
JITTER
ATTENUATOR
RX OR TX
PATH
REMOTE LOOPBACK
DATA
CLOCK
CLOCK
RECOVERY
DIGITAL LOOPBACK
TTIP
G.772 MONITOR
RRING
ANALOG LOOPBACK
DATA SLICER
RTIP
RPOS
B8ZS / HDB3
DECODER
RCLK
RNEG
TPOS
B8ZS / HDB3
ENCODER
TCLK
TNEG
0
1
2
3
4
5
6
7
Datasheet
7
LXT384 — Octal T1/E1/J1 Transceiver
Figure 2. LXT384 Detailed Block Diagram
JTAG
SERIAL/
PARALLEL
PORT
MODE
LOOP 0..7
JASEL
CLKE
MCLK
HARDWARE / SOFTWARE CONTROL
(JTAG INTERFACE)
Transceiver 7
LOS7
LOS
RRING7
TTIP7
DATA
CLOCK
CLOCK
RECOVERY
LINE DRIVER
PULSE
PULSE
SHAPER
JITTER
ATTENUATOR
RX OR TX
PATH
JITTER
ATTENUATOR
RX OR TX
PATH
TRING7
REMOTE LOOPBACK
ANALOG LOOPBACK
RTIP7
DIGITAL LOOPBACK
DATA SLICER
B8ZS / HDB3
DECODER
RPOS7
RCLK7
RNEG7
B8ZS / HDB3
ENCODER
TPOS7
TCLK7
TNEG7
LOS6
RPOS6/RNEG6/RCLK6
TPOS6/TNEG6/TCLK6
RTIP6/RRING6
Transceiver 6
TTIP6/TRING6
LOS5
RTIP5/RRING5
RTIP4/RRING4
TTIP4/TRING4
RTIP3/RRING3
TTIP3/TRING3
RTIP2/RRING2
G.772 Protected Monitoring Point
TTIP5/TRING5
Transceiver 5
RPOS5/RNEG5/RCLK5
TPOS5/TNEG5/TCLK5
LOS4
Transceiver 4
RPOS4/RNEG4/RCLK4
TPOS4/TNEG4/TCLK4
LOS3
Transceiver 3
RPOS3/RNEG3/RCLK3
TPOS3/TNEG3/TCLK3
LOS2
Transceiver 2
RPOS2/RNEG2/RCLK2
TPOS2/TNEG2/TCLK2
TTIP2/TRING2
RTIP1/RRING1
LOS1
Transceiver 1
RPOS1/RNEG1/RCLK1
TPOS1/TNEG1/TCLK1
TTIP1/TRING1
Transceiver 0
LOS0
LOS
TRING0
DATA
CLOCK
CLOCK
RECOVERY
LINE DRIVER
PULSE
PULSE
SHAPER
JITTER
ATTENUATOR
RX OR TX
PATH
JITTER
ATTENUATOR
RX OR TX
PATH
REMOTE LOOPBACK
TTIP0
MUX
DIGITAL LOOPBACK
RTIP0
RRING0
ANALOG LOOPBACK
DATA SLICER
B8ZS / HDB3
DECODER
RPOS0
RCLK0
RNEG0
B8ZS / HDB3
ENCODER
TPOS0
TCLK0
TNEG0
A3 - A0
8
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
1.0
Pin Assignments and Signal Descriptions
144
143
142
141
140
139
138
137
136
135
134
133
132
131
130
129
128
127
126
125
124
123
122
121
120
119
118
117
116
115
114
113
112
111
110
109
TNEG7/UBS7
RCLK7
RPOS7/RDATA7
RNEG7/BPV7
LOS7
RTIP7
RRING7
TVCC7
TTIP7
TRING7
TGND7
RRING6
RTIP6
TGND6
TRING6
TTIP6
TVCC6
RTIP5
RRING5
TVCC5
TTIP5
TRING5
TGND5
RRING4
RTIP4
TGND4
TRING4
TTIP4
TVCC4
CLKE
OE
LOS4
RNEG4/BPV4
RPOS4/RDATA4
RCLK4
TNEG4/UBS4
Figure 3. LXT384 Low-Profile Quad Flate Package (LQFP) 144-Pin Assignments and Package
Markings
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
Part #
LOT #
FPO #
LXT384LE XX
XXXXXX
XXXXXXXX
Rev #
108
107
106
105
104
103
102
101
100
99
98
97
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
75
74
73
TPOS4/TDATA4
TCLK4
LOS5
RNEG5/BPV5
RPOS5/RDATA5
RCLK5
TNEG5/UBS5
TPOS5/TDATA5
TCLK5
TDI
TDO
TCK
TMS
TRST
AT1
AT2
VCCIO1
GNDIO1
VCC1
GND1
MOT/INTL/CODEN
CS/JASEL
ALE/SCLK/AS/LEN2
R/W/RD/LEN1
DS/WR/SDI/LEN0
ACK/RDY/SDO
INT
TCLK2
TPOS2/TDATA2
TNEG2/UBS2
RCLK2
RPOS2/RDATA2
RNEG2/BPV2
LOS2
TCLK3
TPOS3/TDATA3
TPOS0/TDATA0
TNEG0/UBS0
RCLK0
RPOS0/RDATA0
RNEG0/BPV0
LOS0
MUX
TVCC0
TTIP0
TRING0
TGND0
RTIP0
RRING0
TGND1
TRING1
TTIP1
TVCC1
RRING1
RTIP1
TVCC2
TTIP2
TRING2
TGND2
RTIP2
RRING2
TGND3
TRING3
TTIP3
TVCC3
RRING3
RTIP3
LOS3
RNEG3/BPV3
RPOS3/RDATA3
RCLK3
TNEG3/UBS3
37
38
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
64
65
66
67
68
69
70
71
72
TPOS7/TDATA7
TCLK7
LOS6
RNEG6/BPV6
RPOS6/RDATA6
RCLK6
TNEG6/UBS6
TPOS6/TDATA6
TCLK6
MCLK
MODE
A4
A3
A2
A1
A0
VCCIO0
GNDIO0
VCC0
GND0
LOOP0/D0
LOOP1/D1
LOOP2/D2
LOOP3/D3
LOOP4/D4
LOOP5/D5
LOOP6/D6
LOOP7/D7
TCLK1
TPOS1/TDATA1
TNEG1/UBS1
RCLK1
RPOS1/RDATA1
RNEG1/BPV1
LOS1
TCLK0
Package Topside Markings
Marking
Definition
Part #
Unique identifier for this product family.
Rev #
Identifies the particular silicon “stepping” — refer to the specification update for additional stepping information.
Lot #
Identifies the batch.
FPO #
Datasheet
Identifies the Finish Process Order.
9
LXT384 — Octal T1/E1/J1 Transceiver
Figure 4. LXT384 Plastic Ball Grid Array (PBGA) Package Pin Assignments
14
13
12
11
10
9
8
7
6
5
4
3
2
1
A
RCLK
4
RPOS
4
RNEG
4
TVCC
4
TRING
4
TGND
4
RTIP
4
RTIP
7
TGND
7
TRING
7
TVCC
7
RNEG
7
RPOS
7
RCLK
7
A
B
TCLK
4
TPOS
4
TNEG
4
TVCC
4
TTIP
4
TGND
4
RRING
4
RRING
7
TGND
7
TTIP
7
TVCC
7
TNEG
7
TPOS
7
TCLK
7
B
C
RCLK
5
RPOS
5
RNEG
5
TVCC
5
TRING
5
TGND
5
RTIP
5
RTIP
6
TGND
6
TRING
6
TVCC
6
RNEG
6
RPOS
6
RCLK
6
C
D
TCLK
5
TPOS
5
TNEG
5
TVCC
5
TTIP
5
TGND
5
RRING
RRING
5
6
TGND
6
TTIP
6
TVCC
6
TNEG
6
TPOS
6
TCLK
6
D
E
OE
CLKE
LOS
5
LOS
4
LOS
7
LOS
6
MODE
MCLK
E
F
TCK
TDO
TDI
TMS
A
4
A
3
A
2
A
1
F
G
VCCIO
1
AT
2
TRST
GNDIO
1
GNDIO
A
0
LOOP
0
VCCIO
0
0
G
H
VCC
1
AT
1
MOT
GND
1
GND
0
LOOP
1
LOOP
2
VCC
0
H
J
DS
R/W
ALE
CS
LOOP
3
LOOP
4
LOOP
5
LOOP
6
J
K
ACK
INT
LOS
2
LOS
3
LOS
0
LOS
1
MUX
LOOP
7
K
L
TCLK
2
TPOS
2
TNEG
2
TVCC
2
TTIP
2
TGND
2
RRING
RRING
2
1
TGND
1
TTIP
1
TVCC
1
TNEG
1
TPOS
1
TCLK
1
L
M
RCLK
2
RPOS
2
RNEG
2
TVCC
2
TRING
2
TGND
2
RTIP
2
RTIP
1
TGND
1
TRING
1
TVCC
1
RNEG
1
RPOS
1
RCLK
1
M
N
TCLK
3
TPOS
3
TNEG
3
TVCC
3
TTIP
3
TGND
3
RRING
RRING
3
0
TGND
0
TTIP
0
TVCC
0
TNEG
0
TPOS
0
TCLK
0
N
P
RCLK
3
RPOS
3
RNEG
3
TVCC
3
TRING
3
TGND
3
RTIP
3
RTIP
0
TGND
0
TRING
0
TVCC
0
RNEG
0
RPOS
0
RCLK
0
P
14
13
12
11
10
9
8
7
6
5
4
3
2
1
10
LXT384BE
(BOTTOM VIEW)
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 1.
LXT384 Pin Description (Sheet 1 of 12)
Pin #
QFP
Ball #
PBGA
1
1
Symbol
I/O1
B2
TPOS7
DI
Transmit Positive Data Input.
B2
TDATA7
DI
Transmit Data Input.
Description
Transmit Clock Input. During normal operation TCLK is active, and
TPOS and TNEG are sampled on the falling edge of TCLK. If TCLK is
Low, the output drivers enter a low power high-Z mode. If TCLK is High
for more than 16 clock cycles, the pulse shaping circuit is disabled and
the transmit output pulse widths are determined by the TPOS and
TNEG duty cycles.
TCLK
Clocked
2
B1
TCLK7
DI
Operating Mode
Normal operation
H
TAOS (if MCLK supplied)
H
Disable transmit pulse shaping (when
MCLK is not available)
L
Driver outputs enter tri-state
When pulse shaping is disabled, it is possible to overheat and damage
the LXT384 device by leaving transmit inputs high continuously. For
example a programmable ASIC might leave all outputs high until it is
programmed. To prevent this, clock one of these signals: TPOS, TNEG,
TCLK or MCLK. Another solution is to set one of these signals low:
TPOS, TNEG, TCLK, or OE.
Note: The TAOS generator uses MCLK as a timing reference. In order
to assure that the output frequency is within specification limits,
MCLK must have the applicable stability.
3
E3
LOS6
DO
Loss of Signal Output. LOS output is High, indicating a loss of signal,
when the incoming signal has no transitions for a specified time interval.
The LOS condition is cleared and the output pin returns to Low when
the incoming signal has sufficient number of transitions in a specified
time interval (details in LOS functional description).
1. DI: Digital Input; DO: Digital Output; DI/O: Digital Bidirectional Port; AI: Analog Input; AO: Analog Output
S: Power Supply; N.C.: Not Connected.
Datasheet
11
LXT384 — Octal T1/E1/J1 Transceiver
Table 1.
LXT384 Pin Description (Sheet 2 of 12)
Pin #
QFP
Ball #
PBGA
Symbol
I/O1
Description
Receive Negative Data Output.
Bipolar Violation Detect Output.
Receive Positive Data Output.
Receive Data Output
Bipolar Mode:
4
C3
RNEG6
DO
4
C3
BPV6
DO
5
C2
RPOS6
DO
5
C2
RDATA6
DO
In clock recovery mode, these pins act as active High bipolar non return
to zero (NRZ) receive signal outputs. A High signal on RPOS
corresponds to receipt of a positive pulse on RTIP/RRING. A High
signal on RNEG corresponds to receipt of a negative pulse on RTIP/
RRING. These signals are valid on the falling or rising edges of RCLK
depending on the CLKE input.
In Data recovery mode, these pins act as RZ data receiver outputs. The
output polarity is selectable with CLKE (Active High output polarity when
CLKE is High and Active Low Polarity when CLKE is Low).
RPOS and RNEG will go to the high impedance state when the MCLK
pin is Low.
Unipolar Mode:
In uni-polar mode, the LXT384 asserts BPV High if any in-service Line
Code Violation is detected. RDATA acts as the receive data output.
Hardware Mode:
During a LOS condition, RPOS and RNEG will remain active.
Host Mode:
RPOS and RNEG will either remain active or insert AIS into the receive
path. Selection is determined by the RAISEN bit in the GCR register.
Receive Clock Output.
Normal Mode:
6
C1
RCLK6
DO
This pin provides the recovered clock from the signal received at RTIP
and RRING. Under LOS conditions there is a transition from RCLK
signal (derived from the recovered data) to MCLK signal at the RCLK
output.
Data Recovery Mode:
If MCLK is High, the clock recovery circuit is disabled and RPOS and
RNEG are internally connected to an EXOR that is fed to the RCLK
output for external clock recovery applications.
RCLK will be in high impedance state if the MCLK pin is Low.
1. DI: Digital Input; DO: Digital Output; DI/O: Digital Bidirectional Port; AI: Analog Input; AO: Analog Output
S: Power Supply; N.C.: Not Connected.
12
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 1.
LXT384 Pin Description (Sheet 3 of 12)
Pin #
QFP
Ball #
PBGA
Symbol
I/O1
Description
Transmit Negative Data Input.
Unipolar/Bipolar Select Input.
Transmit Positive Data Input.
Transmit Data Input.
Bipolar Mode:
TPOS/TNEG are active High NRZ inputs. TPOS indicates the
transmission of a positive pulse whereas TNEG indicates the
transmission of a negative pulse.
7
D3
TNEG6
DI
7
D3
UBS6
DI
8
D2
TPOS6
DI
8
D2
TDATA6
DI
TPOS
TNEG
Selection
0
0
Space
1
0
Positive Mark
0
1
Negative Mark
1
1
Space
Unipolar Mode:
When TNEG/UBS is pulled High for more than 16 consecutive TCLK
clock cycles, unipolar I/O is selected. In unipolar mode, B8ZS/HDB3 or
AMI encoding/decoding is determined by the CODEN pin (hardware
mode) or by the CODEN bit in the GCR register (software mode).
TDATA is the data input in unipolar I/O mode.
9
D1
TCLK6
DI
Transmit Clock Input.
Master Clock Input. MCLK is an independent, free-running reference
clock. It’s frequency should be 1.544 MHz for T1 operation and 2.048
MHz for E1 operation.
This reference clock is used to generate several internal reference
signals:
• Timing reference for the integrated clock recovery unit
• Timing reference for the integrated digital jitter attenuator
• Generation of RCLK signal during a loss of signal condition
• Reference clock during a blue alarm transmit all ones condition
10
E1
MCLK
DI
• Reference timing for the parallel processor wait state generation
logic
If MCLK is High, the PLL clock recovery circuit is disabled. In this mode,
the LXT384 operates as simple data receiver.
If MCLK is Low, the complete receive path is powered down and the
output pins RCLK, RPOS and RNEG are switched to tri-state mode.
MCLK is not required if LXT384 is used as a simple analog front-end
without clock recovery and jitter attenuation.
Note: Wait state generation via RDY/ACK is not available if MCLK is
not provided.
1. DI: Digital Input; DO: Digital Output; DI/O: Digital Bidirectional Port; AI: Analog Input; AO: Analog Output
S: Power Supply; N.C.: Not Connected.
Datasheet
13
LXT384 — Octal T1/E1/J1 Transceiver
Table 1.
LXT384 Pin Description (Sheet 4 of 12)
Pin #
QFP
Ball #
PBGA
Symbol
I/O1
Description
Mode Select Input. This pin is used to select the operating mode of the
LXT384. In Hardware Mode, the parallel processor interface is disabled
and hardwired pins are used to control configuration and report status.
In Parallel Host Mode, the parallel port interface pins are used to control
configuration and report status.
In Serial Host mode, the serial interface pins: SDI, SDO, SCLK and CS
are used.
11
E2
MODE
DI
MODE
Operating Mode
Low
Hardware Mode
High
Parallel Host Mode
Vcc/2
Serial Host Mode
For Serial Host Mode, the pin should connected to a resistive divider
consisting of two 10 kΩ resistors across VCC and Ground.
12
F4
A4
DI
Address Select Input. In non-multiplexed host mode, this pin is
Address 4 input pin. In hardware mode, this pin must be connected to
Ground.
1. DI: Digital Input; DO: Digital Output; DI/O: Digital Bidirectional Port; AI: Analog Input; AO: Analog Output
S: Power Supply; N.C.: Not Connected.
14
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 1.
LXT384 Pin Description (Sheet 5 of 12)
Pin #
QFP
Ball #
PBGA
Symbol
I/O1
Description
Protected Monitoring/Address Select Inputs.
Hardware Mode
In hardware mode, these pins are used to select a specific port for non
intrusive monitoring. During protection monitoring receiver 0 inputs are
internally connected to a specific transmit or receive port. Receiver 0
routes the data from the selected port to its data and clock recovery
circuits. The data on the monitor port can be routed to TTIP0/TRING0
by activating the remote loopback for channel 0 (TCLK0 must be active
in order for this operation to take place). In addition, the recovered clock
and data can be observed at the RCLK0/RPOS0/RNEG0 outputs.
If A0, A1, and A2 are Low, the LXT384 is configured as octal line
transceiver without monitoring capability.
A3
A2
A1
A0
Selection
0
0
0
0
No Protection Monitoring
0
0
0
1
Receiver 1
0
0
1
0
Receiver 2
0
0
1
1
Receiver 3
0
1
0
0
Receiver 4
13
F3
A3
DI
14
F2
A2
DI
15
F1
A1
DI
0
1
0
1
Receiver 5
16
G3
A0
DI
0
1
1
0
Receiver 6
0
1
1
1
Receiver 7
1
0
0
0
No Protection Monitoring
1
0
0
1
Transmitter 1
1
0
1
0
Transmitter 2
1
0
1
1
Transmitter 3
1
1
0
0
Transmitter 4
1
1
0
1
Transmitter 5
1
1
1
0
Transmitter 6
1
1
1
1
Transmitter 7
Transmitter monitoring is not supported when the respective channel is
set to analog loopback mode.
Host Mode
In non-multiplexed host mode, these pins function as non-multiplexed
address pins.
17
G1
VCCIO0
S
Power (I/O).
18
G4
GNDIO0
S
Ground (I/O).
19
H1
VCC0
S
Power (Core).
20
H4
GND0
S
Ground (Core).
1. DI: Digital Input; DO: Digital Output; DI/O: Digital Bidirectional Port; AI: Analog Input; AO: Analog Output
S: Power Supply; N.C.: Not Connected.
Datasheet
15
LXT384 — Octal T1/E1/J1 Transceiver
Table 1.
LXT384 Pin Description (Sheet 6 of 12)
Pin #
QFP
Ball #
PBGA
Symbol
I/O1
Description
Loopback Mode Select/Parallel Data bus Input &Output.
Host Mode
When a non-multiplexed microprocessor interface is selected, these
pins function as a bi-directional 8-bit data port.
When a multiplexed microprocessor interface is selected, these pins
carry both bi-directional 8-bit data and address inputs A0 -A7.
21
G2
LOOP0/D0
DI/O
22
H3
LOOP1/D1
DI/O
23
H2
LOOP2/D2
DI/O
24
J4
LOOP3/D3
DI/O
25
J3
LOOP4/D4
DI/O
26
J2
LOOP5/D5
DI/O
27
J1
LOOP6/D6
DI/O
28
K1
LOOP7/D7
DI/O
In serial Mode, D0-7 should be grounded.
Hardware Mode
In hardware mode, the LXT384 works in normal operation if this pin is
left open (unconnected).
The LXT384 enters remote loopback mode, if this pin is Low. In this
mode, data on TPOS and TNEG is ignored and data received on RTIP
and RRING is looped around and retransmitted on TTIP and TRING.
Note: in data recovery mode, the pulse template cannot be guaranteed
while in a remote loopback.
The LXT384 enters analog local loopback mode, if this pin is High. In
this mode, data received on RTIP and RRING is ignored and data
transmitted on TTIP and TRING is internally looped around and routed
back to the receive inputs.
Note: When these inputs are left open, they stay in a high impedance
state. Therefore, the layout design should not route signals with
fast transitions near the LOOP pins. This practice will minimize
capacitive coupling.
29
L1
TCLK1
DI
Transmit Clock Input.
30
L2
TPOS1
DI
Transmit Positive Data Input.
30
L2
TDATA1
DI
Transmit Data Input.
31
L3
TNEG1
DI
Transmit Negative Data Input.
31
L3
UBS1
DI
Unipolar/Bipolar Select Input.
32
M1
RCLK1
DO
Receive Clock Output.
33
M2
RPOS1
DO
Receive Positive Data Output.
33
M2
RDATA1
DO
Receive Data Output.
34
M3
RNEG1
DO
Receive Negative Data Output.
34
M3
BPV1
DO
Bipolar Violation Detect Output.
35
K3
LOS1
DO
Loss of Signal Output.
36
N1
TCLK0
DI
Transmit Clock Input.
37
N2
TPOS0
DI
Transmit Positive Data Input.
37
N2
TDATA0
DI
Transmit Data Input.
38
N3
TNEG0
DI
Transmit Negative Data Input.
38
N3
UBS0
DI
Unipolar/Bipolar Select Input.
39
P1
RCLK0
DO
Receive Clock Output.
40
P2
RPOS0
DO
Receive Positive Data.
40
P2
RDATA0
DO
Receive Data Output.
41
P3
RNEG0
DO
Receive Negative Data.
41
P3
BPV0
DO
Bipolar Violation Detect.
42
K4
LOS0
DO
Loss of Signal Output.
1. DI: Digital Input; DO: Digital Output; DI/O: Digital Bidirectional Port; AI: Analog Input; AO: Analog Output
S: Power Supply; N.C.: Not Connected.
16
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 1.
LXT384 Pin Description (Sheet 7 of 12)
Pin #
QFP
Ball #
PBGA
Symbol
I/O1
Description
Multiplexed/Non-Multiplexed Select Input.
43
K2
MUX
DI
44
N4, P4
TVCC0
S
When Low the parallel host interface operates in non-multiplexed mode.
When High the parallel host interface operates in multiplexed mode. In
hardware mode, tie this unused input low.
Transmit Driver Power Supply. Power supply pin for the output driver.
TVCC pins can be connected to either a 3.3V or 5V power supply.
Please refer to the Transmitter description.
Transmit Tip Output.
Transmit Ring Output.
These pins are differential line driver outputs. TTIP and TRING will be in
high impedance state if the TCLK pin is Low or the OE pin is Low. In
software mode, TTIP and TRING can be tristated on a port-by-port
basis by writing a ‘1’ to the OEx bit in the Output Enable Register
(OER).
45
N5
TTIP0
AO
46
P5
TRING0
AO
47
N6, P6
TGND0
S
48
P7
RTIP0
AI
Receive Ring Input.
49
N7
RRING0
AI
These pins are the inputs to the differential line receiver. Data and clock
are recovered and output on the RPOS/RNEG and RCLK pins.
50
L6, M6
TGND1
S
Transmit Driver Ground.
51
M5
TRING1
AO
Transmit Ring Output.
52
L5
TTIP1
AO
Transmit Tip Output.
53
L4, M4
TVCC1
S
Transmit Driver Power Supply.
54
L7
RRING1
AI
Receive Ring Input.
55
M7
RTIP1
AI
Receive Tip Input.
56
L11,
M11
TVCC2
S
Transmit Driver Power Supply.
Transmit Driver Ground. Ground pin for the output driver.
Receive TIP Input.
57
L10
TTIP2
AO
Transmit Tip Output.
58
M10
TRING2
AO
Transmit Ring Output.
59
L9, M9
TGND2
S
Transmit Driver Ground.
60
M8
RTIP2
AI
Receive TIP Input.
61
L8
RRING2
AI
Receive Ring Input.
62
N9, P9
TGND3
S
Transmit Driver Ground.
63
P10
TRING3
AO
Transmit Ring.
64
N10
TTIP3
AO
Transmit Tip Output.
65
N11,
P11
TVCC3
S
Transmit Driver Power Supply.
66
N8
RRING3
AI
Receive Ring Input.
67
P8
RTIP3
AI
Receive Tip Input.
68
K11
LOS3
DO
Loss of Signal Output.
1. DI: Digital Input; DO: Digital Output; DI/O: Digital Bidirectional Port; AI: Analog Input; AO: Analog Output
S: Power Supply; N.C.: Not Connected.
Datasheet
17
LXT384 — Octal T1/E1/J1 Transceiver
Table 1.
LXT384 Pin Description (Sheet 8 of 12)
Pin #
QFP
Ball #
PBGA
Symbol
I/O1
69
P12
RNEG3
DO
Receive Negative Data Output.
69
P12
BPV3
DO
Bipolar Violation Detect Output.
70
P13
RPOS3
DO
Receive Positive Data Output.
70
P13
RDATA3
DO
Receive Data Output.
Description
71
P14
RCLK3
DO
Receive Clock Output.
72
N12
TNEG3
DI
Transmit Negative Data Input.
72
N12
UBS3
DI
Unipolar/Bipolar Select Input.
73
N13
TPOS3
DI
Transmit Positive Data Input.
73
N13
TDATA3
DI
Transmit Data Input.
74
N14
TCLK3
DI
Transmit Clock Input.
75
K12
LOS2
DO
Loss of Signal Output.
76
M12
RNEG2
DO
Receive Negative Data Output.
76
M12
BPV2
DO
Bipolar Violation Detect Output.
77
M13
RPOS2
DO
Receive Positive Data Output.
77
M13
RDATA2
DO
Receive Data Output.
78
M14
RCLK2
DO
Receive Clock Output.
79
L12
TNEG2
DI
Transmit Negative Data Input.
79
L12
UBS2
DI
Unipolar/Bipolar Select Input.
80
L13
TPOS2
DI
Transmit Positive Data Input.
80
L13
TDATA2
DI
Transmit Data Input.
81
L14
TCLK2
DI
Transmit Clock Input.
OD
Interrupt. This active Low, maskable, open drain output requires an
external 10k pull up resistor. If the corresponding interrupt enable bit is
enabled, INT goes Low to flag the host when the LXT384 changes state
(see details in the interrupt handling section). The microprocessor INT
input should be set to level triggering.
82
K13
INT
Data Transfer Acknowledge Output (Motorola Mode).
Ready Output (Intel mode).
Serial Data Output (Serial Mode).
Motorola Mode
83
K14
ACK
DO
83
K14
RDY
DO
83
K14
SDO
DO
A Low signal during a data bus read operation indicates that the
information is valid. A Low signal during a write operation acknowledges
that a data transfer into the addressed register has been accepted
(acknowledge signal).Wait states only occur if a write cycle immediately
follows a previous read or write cycle (e.g. read modify write).
Intel Mode
A High signal acknowledges that a register access operation has been
completed. (Ready Signal) A Low signal on this pin signals that a data
transfer operation is in progress. The pin goes tristate after completion
of a bus cycle.
Serial Mode
If CLKE is High, SDO is valid on the rising edge of SCLK. If CLKE is
Low, SDO is valid on the falling edge of SCLK. This pin goes into High Z
state during a serial port write access.
1. DI: Digital Input; DO: Digital Output; DI/O: Digital Bidirectional Port; AI: Analog Input; AO: Analog Output
S: Power Supply; N.C.: Not Connected.
18
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 1.
LXT384 Pin Description (Sheet 9 of 12)
Pin #
QFP
Ball #
PBGA
Symbol
I/O1
Description
Data Strobe Input (Motorola Mode).
Write Enable Input (Intel mode).
Serial Data Input (Serial Mode).
84
J14
DS
DI
Line Length Equalizer Input (Hardware Mode).
84
J14
WR
DI
Host Mode
84
J14
SDI
DI
84
J14
LEN0
DI
This pin acts as data strobe in Motorola mode and as Write Enable in
Intel mode. In serial mode, this pin is used as Serial Data Input.
Hardware Mode
This pin determines the shape and amplitude of the transmit pulse.
Please refer to Table 2.
Read/Write Input (Motorola Mode).
Read Enable Input (Intel Mode).
Line Length Equalizer Input (Hardware Mode).
85
J13
R/W
DI
Host Mode
85
J13
RD
DI
85
J13
LEN1
DI
This pin functions as the read/write signal in Motorola mode and as the
Read Enable in Intel mode.
Hardware Mode
This pin determines the shape and amplitude of the transmit pulse.
Please refer to Table 2.
Address Latch Enable Input.
Shift Clock Input (Serial Mode).
Address Strobe (Motorola Mode).
Line Length Equalizer Input (Hardware Mode).
86
J12
ALE
DI
Host Mode
86
J12
SCLK
DI
86
J12
AS
DI
The address on the multiplexed address/data bus is clocked into the
device with the falling edge of ALE.
86
J12
LEN2
DI
In serial Host mode, this pin acts as serial shift clock.
In Motorola mode, this pin acts a active Low address strobe.
Hardware Mode
This pin determines the shape and amplitude of the transmit pulse.
Please refer to Table 2.
Chip Select/Jitter Attenuator Select Input.
Host Mode
This active Low input is used to access the serial/parallel interface. For
each read or write operation, CS must transition from High to Low, and
remain Low.
87
J11
CS
87
J11
JASEL
Hardware Mode
DI
This input determines the Jitter Attenuator position:
JASEL
JA Position
L
Transmit Path
H
Receive Path
Z
Disabled
1. DI: Digital Input; DO: Digital Output; DI/O: Digital Bidirectional Port; AI: Analog Input; AO: Analog Output
S: Power Supply; N.C.: Not Connected.
Datasheet
19
LXT384 — Octal T1/E1/J1 Transceiver
Table 1.
LXT384 Pin Description (Sheet 10 of 12)
Pin #
QFP
Ball #
PBGA
Symbol
I/O1
Description
Motorola/Intel/Codec Enable Select Input.
Host Mode:
88
H12
MOT/INTL/
CODEN
DI
When Low, the host interface is configured for Motorola
microcontrollers. When High, the host interface is configured for Intel
microcontrollers.
Hardware Mode:
Determines the line encode/decode selection when in unipolar mode.
When Low, B8ZS/HDB3 encoders/decoders are enabled for T1/E1
respectively. When High, enables AMI encoder/decoder (transparent
mode).
89
H11
GND1
S
Ground (Core).
90
91
H14
VCC1
S
Power (Core).
G11
GNDIO1
S
Ground (I/O).
92
G14
VCCIO1
S
Power (I/O).
93
G13
AT2
AO
JTAG Analog Output Test Port 2.
94
H13
AT1
AI
JTAG Analog Input Test Port 1.
95
G12
TRST
96
F11
TMS
DI
JTAG Test Mode Select Input. Used to control the test logic state
machine. Sampled on rising edge of TCK. TMS is pulled up internally
and may be left disconnected.
97
F14
TCK
DI
JTAG Clock Input. Clock input for JTAG. Connect to GND when not
used.
98
F13
TDO
DO
JTAG Data Output. Test Data Output for JTAG. Used for reading all
serial configuration and test data from internal test logic. Updated on
falling edge of TCK.
99
F12
TDI
DI
JTAG Data Input. Test Data input for JTAG. Used for loading serial
instructions and data into internal test logic. Sampled on rising edge of
TCK. TDI is pulled up internally and may be left disconnected.
100
D14
TCLK5
DI
Transmit Clock Input.
101
D13
TPOS5
DI
Transmit Positive Data Input.
101
D13
TDATA5
DI
Transmit Data Input.
102
D12
TNEG5
DI
Transmit Negative Data Input.
102
D12
UBS5
DI
Unipolar/Bipolar Select Input.
JTAG Controller Reset Input. Input is used to reset the JTAG
controller. TRST is pulled up internally and may be left disconnected.
103
C14
RCLK5
DO
Receive Clock Output.
104
C13
RPOS5
DO
Receive Positive Data Output.
104
C13
RDATA5
DO
Receive Data Output.
105
C12
RNEG5
DO
Receive Negative Data Output.
105
C12
BPV5
DO
Bipolar Violation Detect Output.
106
E12
LOS5
DO
Loss of Signal Output.
107
B14
TCLK4
DI
Transmit Clock Input.
1. DI: Digital Input; DO: Digital Output; DI/O: Digital Bidirectional Port; AI: Analog Input; AO: Analog Output
S: Power Supply; N.C.: Not Connected.
20
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 1.
LXT384 Pin Description (Sheet 11 of 12)
Pin #
QFP
Ball #
PBGA
108
108
Symbol
I/O1
B13
TPOS4
DI
Transmit Positive Data Input.
B13
TDATA4
DI
Transmit Data Input.
109
B12
TNEG4
DI
Transmit Negative Data Input.
109
B12
UBS4
DI
Unipolar/Bipolar Select Input.
110
A14
RCLK4
DO
Receive Clock Output.
111
A13
RPOS4
DO
Receive Positive Data Output.
111
A13
RDATA4
DO
Receive Data Output.
112
A12
RNEG4
DO
Receive Negative Data Output.
112
A12
BPV4
DO
Bipolar Violation Detect Output.
113
E11
LOS4
DO
Loss of Signal Output.
DI
Output Driver Enable Input. If this pin is asserted Low all analog driver
outputs immediately enter a high impedance mode to support
redundancy applications without external mechanical relays. All other
internal circuitry stays active. In software mode, TTIP and TRING can
be tristated on a port-by-port basis by writing a ‘1’ to the OEx bit in the
Output Enable Register (OER).
114
115
E14
E13
OE
CLKE
DI
Description
Clock Edge Select Input. In clock recovery mode, setting CLKE High
causes RDATA or RPOS and RNEG to be valid on the falling edge of
RCLK and SDO to be valid on the rising edge of SCLK. Setting CLKE
Low makes RDATA or RPOS and RNEG to be valid on the rising edge
of RCLK and SDO to be valid on the falling edge of SCLK. In Data
recovery Mode, RDATA or RPOS/RNEG are active High output polarity
when CLKE is High and active Low polarity when CLKE is Low.
CLKE
116
A11,
B11
117
118
RPOS/RNEG
SDO
L
RCLK
SCLK
H
RCLK
SCLK
TVCC4
S
Transmit Driver Power Supply.
B10
TTIP4
AO
Transmit Tip Output.
A10
TRING4
AO
Transmit Ring Output.
119
A9, B9
TGND4
S
Transmit Driver Ground.
120
A8
RTIP4
AI
Receive Tip Input.
121
B8
RRING4
AI
Receive Ring Input.
122
C9, D9
TGND5
S
Transmit Driver Ground.
123
C10
TRING5
AO
Transmit Ring Output.
124
D10
TTIP5
AO
Transmit Tip Output.
125
C11,
D11
TVCC5
S
Transmit Driver Power Supply.
126
D8
RRING5
AI
Receive Ring Input.
127
C8
RTIP5
AI
Receive Tip Input.
128
C4, D4
TVCC6
S
Transmit Driver Power Supply.
1. DI: Digital Input; DO: Digital Output; DI/O: Digital Bidirectional Port; AI: Analog Input; AO: Analog Output
S: Power Supply; N.C.: Not Connected.
Datasheet
21
LXT384 — Octal T1/E1/J1 Transceiver
Table 1.
LXT384 Pin Description (Sheet 12 of 12)
Pin #
QFP
Ball #
PBGA
129
130
Symbol
I/O1
D5
TTIP6
AO
Transmit Tip Output.
C5
TRING6
AO
Transmit Ring Output.
131
C6, D6
TGND6
S
Transmit Driver Ground.
132
C7
RTIP6
AI
Receive Tip Input.
133
D7
RRING6
AI
Receive Ring Input.
134
A6, B6
TGND7
S
Transmit Driver Ground.
135
A5
TRING7
AO
Transmit Ring Output.
136
B5
TTIP7
AO
Transmit Tip Output.
137
A4, B4
TVCC7
S
Transmit Driver Power Supply.
138
B7
RRING7
AI
Receive Ring Input.
139
A7
RTIP7
AI
Receive Tip Input.
140
E4
LOS7
DO
Loss of Signal Output.
141
A3
RNEG7
DO
Receive Negative Data Output.
141
A3
BPV7
DO
Bipolar Violation Detect Output.
142
A2
RPOS7
DO
Receive Positive Data Output.
142
A2
RDATA7
DO
Receive Data Output.
Description
143
A1
RCLK7
DO
Receive Clock Output.
144
B3
TNEG7
DI
Transmit Negative Data Input.
144
B3
UBS7
DI
Unipolar/Bipolar Select Input.
1. DI: Digital Input; DO: Digital Output; DI/O: Digital Bidirectional Port; AI: Analog Input; AO: Analog Output
S: Power Supply; N.C.: Not Connected.
2.0
Functional Description
Figure 1 is a block diagram of the LXT384. The LXT384 is a fully integrated octal line interface
unit designed for T1 1.544 Mbps and E1 2.048 Mbps short haul applications.
Each transceiver front end interfaces with four lines, one pair for transmit, one pair for receive.
These two lines comprise a digital data loop for full duplex transmission.
The LXT384 can be controlled through hard-wired pins or by a microprocessor through a serial or
parallel interface (Host mode).
The transmitter timing reference is TCLK, and the receiver reference clock is MCLK. The LXT384
is designed to operate without any reference clock when used as an analog front-end (line driver
and data recovery). MCLK is mandatory if the on chip clock recovery capability is used. All eight
clock recovery circuits share the same reference clock defined by the MCLK input signal.
2.1
Initialization
During power up, the transceiver remains static until the power supply reaches approximately 60%
of VCC. During power-up, an internal reset sets all registers to their default values and resets the
status and state machines for the LOS.
22
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
2.1.1
Reset Operation
Writing to the reset register (RES) initiates a 1 microsecond reset cycle, except in Intel nonmultiplexed mode. In Intel non-multiplexed mode, the reset cycle takes 2 microseconds. Please
refer to Host mode section for more information. This operation sets all LXT384 registers to their
default values.
2.2
Receiver
The eight receivers in the LXT384 are identical. The following paragraphs describe the operation
of one.
The twisted-pair input is received via a 1:2 step down transformer. Positive pulses are received at
RTIP, negative pulses at RRING. Recovered data is output at RPOS and RNEG in the bipolar mode
and at RDATA in the unipolar mode. The recovered clock is output at RCLK. RPOS/RNEG
validation relative to RCLK is pin selectable (CLKE).
The receive signal is processed through the peak detector and data slicers. The peak detector
samples the received signal and determines its maximum value. A percentage of the peak value is
provided to the data slicers as a threshold level to ensure optimum signal-to-noise ratio. For DSX-1
applications (line length inputs LEN2-0 from 011 to 111) the threshold is set to 70% (typical) of the
peak value. This threshold is maintained above the specified level for up to 15 successive zeros
over the range of specified operating conditions. For E1 applications (LEN2-0 = 000), the
threshold is 50% (typical).
The receiver is capable of accurately recovering signals with up to 12 dB of attenuation (from 2.4
V), corresponding to a received signal level of approximately 500 mV. Maximum line length is
1500 feet of ABAM cable (approximately 6 dB of attenuation). Regardless of received signal level,
the peak detectors are held above a minimum level of 0.150 V (typical) to provide immunity from
impulsive noise.
After processing through the data slicers, the received signal goes to the data and timing recovery
section. The data and timing recovery circuits provide an input jitter tolerance better than required
by Pub 62411 and ITU G.823, as shown in Test Specifications, Figure 33.
Depending on the options selected, recovered clock and data signals may be routed through the
jitter attenuator, through the B8ZS/HDB3/AMI decoder, and may be output to the framer as either
bipolar or unipolar data.
2.2.1
Loss of Signal Detector
The loss of signal detector in the LXT384 uses a dedicated analog and digital loss of signal
detection circuit. It is independent of its internal data slicer comparators and complies to the latest
ITU G.775 and ANSI T1.231 recommendations. Under software control, the detector can be
configured to comply to the ETSI ETS 300 233 specification (LACS Register). In hardware mode,
the LXT384 supports LOS per G.775 for E1 and ANSI T1.231 for T1 operation.
The receiver monitor loads a digital counter at the RCLK frequency. The counter is incremented
each time a zero is received, and reset to zero each time a one (mark) is received. Depending on the
operation mode, a certain number of consecutive zeros sets the LOS signal. The recovered clock is
replaced by MCLK at the RCLK output with a minimum amount of phase errors. MCLK is
Datasheet
23
LXT384 — Octal T1/E1/J1 Transceiver
required for receive operation. When the LOS condition is cleared, the LOS flag is reset and
another transition replaces MCLK with the recovered clock at RCLK. RPOS/RNEG will reflect the
data content at the receiver input during the entire LOS detection period for that channel.
2.2.1.1
E1 Mode
In G.775 mode, a loss of signal is detected if the signal is below 200mV typ. for 32 consecutive
pulse intervals. When the received signal reaches 12.5% ones density (4 marks in a sliding 32-bit
period) with no more than 15 consecutive zeros and the signal level exceeds 250mV typ., the LOS
flag is reset and another transition replaces MCLK with the recovered clock at RCLK.
In ETSI 300 233 mode, a loss of signal is detected if the signal is below 200mV for 2048
consecutive intervals (1 ms). The LOS condition is cleared and the output pin returns to Low when
the incoming signal has transitions when the signal level is equal or greater than 250mV for more
than 32 consecutive pulse intervals.
2.2.1.2
T1 Mode
The T1.231 LOS detection criteria is employed. LOS is detected if the signal is below 200mV for
175 contiguous pulse positions. The LOS condition is terminated upon detecting an average pulse
density of 12.5% over a period of 175 contiguous pulse positions starting with the receipt of a
pulse. The incoming signal is considered to have transitions when the signal level is equal or
greater than 250mV.
2.2.1.3
Data Recovery Mode
In data recovery mode, the LOS digital timing is derived from a internal self timed circuit. RPOS/
RNEG stay active during loss of signal. The analog LOS detector complies with ITU-G.775
recommendation. The LXT384 monitors the incoming signal amplitude. Any signal below 200mV
for more than 30µs (typical) will assert the corresponding LOS pin. The LOS condition is cleared
when the signal amplitude rises above 250mV. The LXT384 requires more than 10 and less than
255 bit periods to declare a LOS condition in accordance to ITU G.775.
2.2.2
Alarm Indication Signal (AIS) Detection
The AIS detection is performed by the receiver independent of any loopback mode. This feature is
available in host mode only with clock recovery. Because there is no clock in data recovery mode,
AIS detection will not work in that mode. AIS requires MCLK to have clock applied, since this
function depends on the clock to count the number of ones in an interval.
2.2.2.1
E1 Mode
Two different detection modes are available depending on the LACS register setting:
• ETSI ETS300233 Mode
The AIS condition is declared when the received data stream contains less than 3 zeros within
a period of 512 bits.
The AIS condition is cleared when 3 or more zeros within 512 bits are detected.
• ITU G.775 Mode
The AIS condition is declared when, within two consecutive 512 bit periods, less than 3 zeros
are detected for each 512 bit period.
24
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
The AIS condition is cleared when, within two consecutive 512 bit periods, 3 or more zeros
are detected for each 512 bit period.
2.2.2.2
T1 Mode
ANSI T1.231 detection is employed.
The AIS condition is declared when less than 9 zeros are detected in any string of 8192 bits. This
corresponds to a 99.9% ones density over a period of 5.3ms.
The AIS condition is cleared when the received signal contains 9 or more zeros in any string of
8192 bits.
2.2.3
Receive Alarm Indication Signal (RAIS)
The receiver will generate all ones to RPOS and RNEG outputs upon LOS, when bit 6, RAISEN,
for Receive Alarm Indication Signal Enable, is set in the Global Control Register, GCR. This can
affect the AIS status by setting to one if the signal at RTIP and RRING is all zeroes, or be clearing
to zero if the signal at RTIP and RRING is all ones. Because of this, mask the AIS interrupt enable
bits before setting or resetting RAISEN. This will prevent inadvertent interrupts during
programming.
2.2.4
In Service Code Violation Monitoring
In unipolar I/O mode with HDB3/B8ZS decoding, the LXT384 reports bipolar violations on
RNEG/BPV for one RCLK period for every HDB3/B8ZS code violation that is not part of the zero
code substitution rules. In AMI mode, all bipolar violations (two consecutive pulses with the same
polarity) are reported at the BPV output.
2.3
Transmitter
The eight low power transmitters of the LXT384 are identical. Transmit data is clocked serially
into the device at TPOS/TNEG in the bipolar mode or at TDATA in the unipolar mode. The
transmit clock (TCLK) supplies the input synchronization. Unipolar I/O and HDB3/B8ZS/AMI
encoding/decoding is selected by pulling TNEG High for more than 16 consecutive TCLK clock
cycles. The transmitter samples TPOS/TNEG or TDATA inputs on the falling edge of TCLK. Refer
to the Test Specifications Section for MCLK and TCLK timing characteristics. If TCLK is not
supplied, the transmitter remains powered down and the TTIP/TRING outputs are held in a High Z
state. In addition, fast output tristatability is also available through the OE pin (all ports) and/or the
port’s OEx bit in the Output Enable Register (OER).
Zero suppression is available only in Unipolar Mode. The two zero-suppression types are B8ZS,
used in T1 environments, and HDB3, used in E1 environments. The scheme selected depends on
whether the device is set for T1 or E1 operation (determined by LEN2-0 pulse shaping settings).
The LXT384 also supports AMI line coding/decoding as shown in Figure 5. In Hardware mode,
AMI coding/decoding is selected by the CODEN pin. In host mode, AMI coding/decoding is
selected by bit 4 in the GCR (Global Control Register).
Datasheet
25
LXT384 — Octal T1/E1/J1 Transceiver
Figure 5. 50% AMI Encoding
TTIP
Bit Cell
1
0
1
TRING
Each output driver is supplied by a separate power supply (TVCC and TGND). The transmit pulse
shaper is bypassed if no MCLK is supplied while TCLK is pulled High. In this case TPOS and
TNEG control the pulse width and polarity on TTIP and TRING. With MCLK supplied and TCLK
pulled High, the driver enters TAOS (Transmit All Ones pattern). Note: the TAOS generator uses
MCLK as a timing reference. In order to assure that the output frequency is within specification
limits, MCLK must have the applicable stability. TAOS is inhibited during Remote Loopback.
2.3.1
Transmit Pulse Shaping
The transmitted pulse shape is internally generated using a high speed D/A converter. Shaped
pulses are further applied to the line driver for transmission onto the line at TTIP and TRING. The
line driver provides a constant low output impedance regardless of whether it is driving marks,
spaces or if it is in transition. This well controlled dynamic impedance provides excellent return
loss when used with external precision resistors (± 1% accuracy) in series with the transformer.
2.3.1.1
Hardware Mode
In hardware mode, pins LEN0-2 determine the pulse shaping as described in Table 2. The LEN
settings also determine whether the operating mode is T1 or E1.
Note:
In hardware mode, all eight ports will share the same pulse shaping setting. Independent pulse
shaping for each channel is available in host mode.
2.3.1.2
Host Mode
In Host Mode, the contents of the Pulse Shaping Data Register (PSDAT) determines the shape of
pulse output at TTIP/TRING. Please refer to Table 24 and Table 25.
26
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 2.
Line Length Equalizer Inputs
LEN2
LEN1
LEN0
Line Length1
Cable Loss2
0
1
1
0 - 133 ft. ABAM
0.6 dB
1
0
0
133 - 266 ft. ABAM
1.2 dB
1
0
1
266 - 399 ft. ABAM
1.8 dB
399 - 533 ft. ABAM
2.4 dB
533 - 655 ft. ABAM
3.0 dB
1
1
0
1
1
1
0
0
0
E1 G.703, 75Ω coaxial cable and 120 Ω twisted pair
cable.
Operation Mode
T1
E1
1. Line length from LXT384 to DSX-1 cross-connect point.
2. Maximum cable loss at 772KHz.
2.3.1.3
Output Driver Power Supply
The output driver power supply (TVCC pins) can be either 3.3V or 5V nominal. When TVCC=5V,
LXT384 drives both E1 (75Ω/120Ω) and T1 100Ω lines through a 1:2 transformer and 11Ω/9.1Ω
series resistors.
When TVCC=3.3V, the LXT384 drives E1 (75Ω/120Ω) lines through a 1:2 transformer and 11Ω
series resistor. A configuration with a 1:2 transformer and without series resistors should be used to
drive T1 100Ω lines.
The Channel 4 (TVCC4) power supply pin is used to determine 3.3V or 5.0V transmit operation.
Removing the series resistors for T1 applications with TVCC=3.3V, improves the power
consumption of the device. See Table 36.
On the other hand, series resistors in the transmit configuration improve the transmit return loss
performance. Good transmit return loss performance minimizes reflections in harsh cable
environments. In addition, series resistors provide protection against surges coupled to the device.
The resistors should be used in systems requiring protection switching without external relays.
Please refer to Figure 6 for the recommended external line circuitry.
2.3.1.4
Power Sequencing
For the LXT384, we recommend sequencing TVCC first then VCC second or at the same time as
TVCC to prevent excessive current draw.
2.4
Driver Failure Monitor
The LXT384 transceiver incorporates an internal power Driver Failure Monitor (DFM) in parallel
with TTIP and TRING that is capable of detecting secondary shorts without cable. DFM is
available only in configurations with no transmit series resistors (T1 mode with TVCC=3.3V).
This feature is available in the serial and parallel host modes but not available in the hardware
mode of operation.
A capacitor, charged via a measure of the driver output current and discharged by a measure of the
maximum allowable current, is used to detect a secondary short failure. Secondary shorted lines
draw excess current, overcharging the cap. When the capacitor charge deviates outside the nominal
Datasheet
27
LXT384 — Octal T1/E1/J1 Transceiver
charge window, a driver short circuit fail (DFM) is reported in the respective register by setting an
interrupt. During a long string of spaces, a short-induced overcharge eventually bleeds off, clearing
the DFM flag.
Note: unterminated lines of adequate length (λ/4) may effectively behave as short-circuits as seen
by the driver and therefore trigger the DFM. Under these circumstances, the alarm should be
disabled.
In addition, LXT384 features output driver short-circuit protection. When the output current
exceeds 100 mA, LXT384 limits the driver’s output voltage to avoid damage.
28
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Figure 6. External Transmit/Receive Line Circuitry
TVCC
TVCC
TVS1
68µF
1
0.1µF
TVCC
TGND
TVCC
4
D4
RT
1:2
TTIP
D3
0.47µF
3.3V
TVCC
0.1µF
Tx LINE
2
560pF
VCC
D2
GND
TRING
RT
3
D1
LXT384
(ONE CHANNEL)
1kΩ
1:2
RTIP
RR
Rx LINE
0.22µF
RR
RRING
1kΩ
1
Common decoupling capacitor for all TVCC and TGND pins.
2
Typical value. Adjust for actual board parasitics to obtain optimum return loss.
3
Refer to Transformer Specifications Table for transformer specifications.
4
DC blocking capacitor needed when pulse shaping is disabled. See pin
description for TCLK7, pin 2 of QFP package in Table 1.
Component
75Ω Coax
120Ω Twisted Pair
100Ω Twisted Pair
TVCC = 5V
100Ω Twisted Pair
TVCC = 3.3V
RT
11Ω ± 1%
11Ω ± 1%
9.1Ω ± 1%
0Ω
9.31Ω ± 1%
15.0Ω ± 1%
12.4Ω ± 1%
12.4Ω ± 1%
RR
D1 - D4
TVS1
Datasheet
International Rectifier.............11DQ04 or 10BQ060
Motorola.......................................MBR0540T1
SGS-Thomson..............SMLVT 3V3 3.3V Transient Voltage Suppressor (TVCC=3.3V)
Semtech.......................SMCJ5.0AC 5.0V Transient Voltage Suppressor (TVCC=5.0V)
29
LXT384 — Octal T1/E1/J1 Transceiver
2.5
Line Protection
Figure 6 on page 29 shows recommended line interface circuitry. In the receive side, the 1 kΩ
series resistors protect the receiver against current surges coupled into the device. Due to the high
receiver impedance (70 kΩ typ.) the resistors do not affect the receiver sensitivity. In the transmit
side, the Schottky diodes D1-D4 protect the output driver.While not mandatory for normal
operation, these protection elements are strongly recommended to improve the design robustness.
2.6
Jitter Attenuation
A digital Jitter Attenuation Loop (JAL) combined with a FIFO provides Jitter attenuation. The JAL
is internal and requires no external crystal nor high-frequency (higher than line rate) reference
clock.
In Host Mode, the Global Control Register (GCR) determines whether the JAL is positioned in the
receive or transmit path. In Hardware Mode, the JAL position is determined by the JASEL pin.
The FIFO is a 32 x 2-bit or 64 x 2-bit register (selected by the FIFO64 bit in the GCR). Data is
clocked into the FIFO with the associated clock signal (TCLK or RCLK), and clocked out of the
FIFO with the dejittered JAL clock (Figure 7). When the FIFO is within two bits of overflowing or
underflowing, the FIFO adjusts the output clock by 1/8 of a bit period. The Jitter Attenuator
produces a constant delay of 16 or 32 bits in the associated path (refer to test specifications). This
feature can be used for hitless switching applications. This advanced digital jitter attenuator meets
latest jitter attenuation specifications. See Table 3.
Under software control, the low limit jitter attenuator corner frequency depends on FIFO length
and the JACF bit setting (this bit is in the GCR register). In Hardware Mode, the FIFO length is
fixed to 64 bits. The corner frequency is fixed to 6 Hz for T1 mode and 3.5 Hz for E1 mode.
Table 3.
Jitter Attenuation Specifications
T1
E1
AT&T Pub 62411
1
GR-253-CORE
ITU-T G.736
ITU-T G.7423
ITU-T G.7834
TR-TSY-000009
2
ETSI CTR12/13
BAPT 220
1.
2.
3.
4.
30
Category I, R5-203.
Section 4.6.3.
Section 6.2 When used with the SXT6234 E2-E1 mux/demux.
Section 6.2.3.3 combined jitter when used with the SXT6251 21E1 mapper.
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Figure 7. Jitter Attenuator Loop
FIFO64
TPOS
RPOSi
TPOSo
RPOS
TNEG
RNEGi
TNEGo
FIFO
IN CK
TCLK
DPLL
IN
RCLKi
TCLK
RCLK
OUT
JASEL0-1
JASEL0-1
x 32
MCLK
RNEG
OUT CK
JACF
GCR control bits
2.7
Loopbacks
The LXT384 offers three loopback modes for diagnostic purposes. In hardware mode, the loopback
mode is selected with the LOOPn pins. In software mode, the ALOOP, DLOOP and RLOOP
registers are employed.
2.7.1
Analog Loopback
When selected, the transmitter outputs (TTIP & TRING) are connected internally to the receiver
inputs (RTIP & RRING) as shown in Figure 8. Data and clock are output at RCLK, RPOS &
RNEG pins for the corresponding transceiver. Note: signals on the RTIP & RRING pins are
ignored during analog loopback.
TCLK
TPOS
TNEG
HDB3/B8ZS
Encoder*
JA*
RCLK
RPOS
RNEG
HDB3/B8ZS
Decoder *
Figure 8. Analog Loopback
JA*
Timing &
Control
TTIP
Timing
Recovery
RTIP
TRING
RRING
* If Enabled
Datasheet
31
LXT384 — Octal T1/E1/J1 Transceiver
2.7.2
Digital Loopback
The digital loopback function is available in software mode only. When selected, the transmit clock
and data inputs (TCLK, TPOS & TNEG) are looped back and output on the RCLK, RPOS &
RNEG pins (see Figure 9). The data presented on TCLK, TPOS & TNEG is also output on the
TTIP & TRING pins. Note: signals on the RTIP & RRING pins are ignored during digital
loopback.
RCLK
RPOS
RNEG
HDB3/B8ZS
Encoder*
TCLK
TPOS
TNEG
Timing &
Control
TTIP
JA*
HDB3/B8ZS
Decoder*
Figure 9. Digital Loopback
JA*
Timing
Recovery
RTIP
TRING
RRING
* If Enabled
2.7.3
Remote Loopback
During remote loopback (see Figure 10), the RCLK, RPOS & RNEG outputs routed to the transmit
circuits and output on the TTIP & TRING pins. Note: input signals on the TCLK, TPOS & TNEG
pins are ignored during remote loopback.
TCLK
TPOS
TNEG
HDB3/B8ZS
Encoder*
JA*
RCLK
RPOS
RNEG
HDB3/B8ZS
Decoder*
Figure 10. Remote Loopback
JA*
Timing &
Control
TTIP
Timing
Recovery
RTIP
TRING
RRING
* If Enabled
Note:
2.7.4
In data recovery mode, the pulse template cannot be guaranteed while in a remote loopback.
Transmit All Ones (TAOS)
In Hardware mode, the TAOS mode is set by pulling TCLK High for more than 16 MCLK cycles.
In software mode, TAOS mode is set by asserting the corresponding bit in the TAOS Register. In
addition, automatic ATS insertion (in case of LOS) may be set using the ATS Register. Note: the
TAOS generator uses MCLK as a timing reference, therefore TAOS doesn’t work in data recovery
mode. In order to assure that the output frequency is within specification limits, MCLK must have
the applicable stability. DLOOP does not function when TAOS is active.
32
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Figure 11. TAOS Data Path
MCLK
TCLK
TPOS
TNEG
HDB3/B8ZS
Encoder*
RCLK
RPOS
RNEG
HDB3/B8ZS
Decoder*
TAOS mode
Timing &
Control
TTIP
TRING
(ALL 1’s)
Timing
Recovery
JA*
RTIP
RRING
* If Enabled
Figure 12. TAOS with Digital Loopback
MCLK
HDB3/B8ZS
Encoder*
JA*
RCLK
RPOS
RNEG
HDB3/B8ZS
Decoder*
TAOS Mode
TCLK
TPOS
TNEG
JA*
Timing &
Control
TTIP
TRING
(ALL 1’s)
Timing
Recovery
RTIP
RRING
* If Enabled
Figure 13. TAOS with Analog Loopback
MCLK
TAOS Mode
RCLK
RPOS
RNEG
Timing &
Control
HDB3/B8ZS
Encoder*
HDB3/B8ZS
Decoder*
TCLK
TPOS
TNEG
TTIP
TRING
(ALL 1’s)
JA*
Timing
Recovery
RTIP
RRING
* If Enabled
2.8
G.772 Performance Monitoring
The LXT384 can be configured as an octal line interface unit with all channels working as regular
transceivers. In applications using only seven channels, the eighth channel can be configured to
monitor any of the remaining channels inputs or outputs. The monitoring is non-intrusive per ITUT G.772. Figure 1 on page 7 illustrates this concept.
Datasheet
33
LXT384 — Octal T1/E1/J1 Transceiver
The monitored line signal (input or output) goes through channel 0 clock and data recovery. The
signal can be observed digitally at the RCLK/RPOS/RNEG outputs. This feature can also be used
to create timing interfaces derived from a E1 signal. Channel 0 also displays the appropriate LOS
state for the monitored channel, both in transmit and receive directions.
In addition, channel 0 can be configured to a Remote Loopback while in monitoring mode (TCLK0
must be active in order for this operation to take place). This will output the same data as in the
signal being monitored at the channel 0 output (TTIP/TRING). The output signal can then be
connected to a standard test equipment with an E1 electrical interface for monitoring purposes (non
-intrusive monitoring).
2.9
Hitless Protection Switching (HPS)
The LXT384 transceivers include an output driver tristatability feature for T1/E1 redundancy
applications. This feature greatly reduces the cost of implementing redundancy protection by
eliminating external relays. Please refer to Application Note 119 for guidelines for implementing
redundancy systems for both T1 and E1 operation using the LXT380/1/4/6/8.
2.10
Operation Mode Summary
Table 4 lists summarizes all the LXT384 hardware settings and corresponding operating modes.
Table 4.
Operation Mode Summary
MCLK
TCLK
LOOP1
Receive Mode
Transmit Mode
Clocked
Clocked
Open
Data/Clock recovery
Pulse Shaping ON
No Loopback
Clocked
Clocked
L
Data/Clock recovery
Pulse Shaping ON
Remote Loopback
Clocked
Clocked
H
Data/Clock recovery
Pulse Shaping ON
Analog Loopback
Clocked
L
Open
Data/Clock recovery
Power down
No Loopback
Loopback
Clocked
L
L
Data/Clock Recovery
Power down
No effect on op.
Clocked
L
H
Data/Clock Recovery
Power down
No Analog Loopback
Clocked
H
Open
Data/Clock Recovery
Transmit All Ones
No Loopback
Clocked
H
L
Data/Clock Recovery
Pulse Shaping ON
Remote Loopback
Clocked
H
H
Data/Clock Recovery
Transmit All Ones
No effect on op.
L
Clocked
Open
Power Down
Pulse Shaping ON
No Loopback
L
Clocked
L
Power Down
Pulse Shaping ON
No Remote Loopback
L
Clocked
H
Power Down
Pulse Shaping ON
No effect on op.
L
H
Open
Power Down
Pulse Shaping OFF
No Loopback
L
H
L
Power Down
Pulse Shaping OFF
No Remote Loop
L
H
H
Power Down
Pulse Shaping OFF
No effect on op.
L
L
X
Power Down
Power down
No Loopback
H
Clocked
Open
Data Recovery
Pulse Shaping ON
No Loopback
H
Clocked
L
Data Recovery
Pulse Shaping OFF
Remote Loopback
1. Hardware mode only.
34
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 4.
Operation Mode Summary (Continued)
MCLK
TCLK
H
Clocked
H
L
H
L
H
H
H
H
LOOP1
Receive Mode
Transmit Mode
Loopback
H
Data Recovery
Pulse Shaping ON
Analog Loopback
Open
Data Recovery
Power down
No Loopback
L
Data Recovery
Pulse Shaping OFF
Remote Loopback
Open
Data Recovery
Pulse Shaping OFF
No Loopback
H
L
Data Recovery
Pulse Shaping OFF
Remote Loopback
H
H
Data Recovery
Pulse Shaping OFF
Analog Loopback
1. Hardware mode only.
2.11
Interfacing with 5V Logic
The LXT384 can interface directly with 5V TTL family devices. The internal input pads are
tolerant to 5V outputs from TTL and CMOS family devices.
2.12
Parallel Host Interface
The LXT384 incorporates a highly flexible 8-bit parallel microprocessor interface. The interface is
generic and is designed to support both non-multiplexed and multiplexed address/data bus systems
for Motorola and Intel bus topologies. Two pins (MUX and MOT/INTL) select four different
operating modes as shown in Table 5.
Table 5.
Microprocessor Interface Selection
Pin
Operating Mode
MUX
MOT/INTL
Low
Low
Motorola, Non-Multiplexed
Low
High
Intel, Non-Multiplexed
High
Low
Motorola, Multiplexed
High
High
Intel, Multiplexed
The interface includes an address bus (A4 - A0) and a data bus (D7 - D0) for non-multiplexed
operation and an 8-bit address/data bus for multiplexed operation. WR, RD, R/W, CS, ALE, DS,
INT and RDY/ACK are used as control signals. A significant enhancement is an internal wait-state
generator that controls an Intel and Motorola compatible handshake output signal (RDY/ACK). In
Motorola mode, ACK Low signals valid information is on the data bus. During a write cycle a Low
signal acknowledges the acceptance of the write data.
In Intel mode, RDY High signals to the controlling processor that the bus cycle can be completed.
While Low the microprocessor must insert wait states. This allows the LXT384 to interface with
wait-state capable microcontrollers, independent of the processor bus speed. To activate this
function a reference clock is required on the MCLK pin.
There is one exception to write cycle timing for Intel non-multiplexed mode: Register 0Ah, the
reset register. Because of timing issues, the RDY line remains high after the first part of the cycle is
done, not signalling write cycle completion with another transition low. Add 2 microseconds of
Datasheet
35
LXT384 — Octal T1/E1/J1 Transceiver
delay to allow the reset cycle to completely initialize the device before proceeding. The overall
duration of the Reset cycle from CS low to Reset cycle completion is 3 microseconds when using
Intel non-multiplexed host mode.
An additional active Low interrupt output signal indicates alarm conditions like LOS and DFM to
the microprocessor.
The LXT384 has a 5-bit address bus and provides 22 user accessible 8-bit registers for
configuration, alarm monitoring and control of the chip.
2.12.1
Motorola Interface
The Motorola interface is selected by asserting the MOT/INTL pin Low. In non-multiplexed mode,
the falling edge of DS is used to latch the address information on the address bus. In multiplexed
operation the address on the multiplexed address data bus is latched into the device with the falling
edge of AS. In non-multiplexed mode, AS should be pulled High.
The R/W signal indicates the direction of the data transfer. The DS signal is the timing reference
for all data transfers and typically has a duty cycle of 50%. A read cycle is indicated by asserting R/
W High with a falling edge on DS. A write cycle is indicated by asserting R/W Low with a rising
edge on DS.
Both cycles require the CS signal to be Low and the Address pins to be actively driven by the
microprocessor. Note: CS and DS can be connected together in Motorola mode. In a write cycle,
the data bus is driven by the microprocessor. In a read cycle, the bus is driven by the LXT384.
2.12.2
Intel Interface
The Intel interface is selected by asserting the MOT/INTL pin High. The LXT384 supports nonmultiplexed interfaces with separate address and data pins when MUX is asserted Low, and
multiplexed interfaces when MUX is asserted High. The address is latched in on the falling edge of
ALE. In non-multiplexed mode, ALE should be pulled High. R/W is used as the RD signal and DS
is used as the WR signal. A read cycle is indicated to the LXT384 when the processor asserts RD
Low while the WR signal is held High. A write operation is indicated to the LXT384 by asserting
WR Low while the RD signal is held High. Both cycles require the CS signal to be Low.
2.13
Interrupt Handling
2.13.1
Interrupt Sources
There are three interrupt sources:
• Status change in the LOS (Loss of Signal) status register (04H). The LXT384 analog/digital
loss of signal processor continuously monitors the receiver signal and updates the specific
LOS status bit to indicate presence or absence of a LOS condition.
• Status change in the DFM (Driver Failure Monitoring) status register (05H). The LXT384
smart power driver circuit continuously monitors the output drivers signal and updates the
specific DFM status bit to indicate presence or absence of a secondary driver short circuit
condition.
• Status change in the AIS (Alarm Indication Signal) status register (13H). The LXT384
receiver monitors the incoming data stream and updates the specific AIS status bit to indicate
presence or absence of a AIS condition.
36
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
2.13.2
Interrupt Enable
The LXT384 provides a latched interrupt output (INT). An interrupt occurs any time there is a
transition on any enabled bit in the status register. Registers 06H, 07H and 14H are the LOS, DFM
and AIS interrupt enable registers (respectively). Writing a logic “1” into the mask register will
enable the respective bit in the respective Interrupt status register to generate an interrupt. The
power-on default value is all zeroes. The setting of the interrupt enable bit does not affect the
operation of the status registers.
Registers 08H, 09H and 15H are the LOS, DFM and AIS (respectively) interrupt status registers.
When there is a transition on any enabled bit in a status register, the associated bit of the interrupt
status register is set and an interrupt is generated (if one is not already pending). When an interrupt
occurs, the INT pin is asserted Low. The output stage of the INT pin consists only of a pull-down
device; an external pull-up resistor of approximately 10k ohm is required to support wired-OR
operation.
2.13.3
Interrupt Clear
When an interrupt occurs, the interrupt service routine (ISR) should read the interrupt status
registers (08H, 09H and 15H) to identify the interrupt source. Reading the Interrupt Status register
clears the "sticky" bit set by the interrupt. Automatically clearing the register prepares it for the
next interrupt.
The ISR should then read the corresponding status monitor register to obtain the current status of
the device. Note: there are three status monitor registers: the LOS (04H), the DFM (05H) and the
AIS (013H). Reading either status monitors register will clear its corresponding interrupts on the
rising edge of the read or data strobe. When all pending interrupts are cleared, the INT pin goes
High.
2.14
Serial Host Mode
The LXT384 operates in Serial Host Mode when the MODE pin is tied to VCCIO÷2. Figure 14
shows the SIO data structure. The registers are accessible through a 16 bit word: an 8bit Command/
Address byte (bits R/W and A1-A7) and a subsequent 8bit data byte (bits D0-7). Bit R/W
determines whether a read or a write operation occurs. Bits A5-0 in the Command/Address byte
address specific registers (the address decoder ignores bits A7-6). The data byte depends on both
the value of bit R/W and the address of the register as set in the Command/Address byte.
Datasheet
37
LXT384 — Octal T1/E1/J1 Transceiver
Figure 14. Serial Host Mode Timing
CS
SCLK
INPUT DATA BYTE
ADDRESS/COMMAND BYTE
SDI
R/W
A1
A2
A3
A4
A5
A6
X
A7
X
SDO - REMAINS HIGH Z
D0
D1
D2
D3
D4
D5
D6
D7
SDO IS DRIVEN WHEN R/W = 1
R/W = 1: Read from LXT384
R/W = 0: Write to LXT384
X = Don’t care
3.0
Table 6.
Register Descriptions
Serial and Parallel Port Register Addresses (Sheet 1 of 2)
Address
38
Name
Symbol
ID Register
Mode
Serial Port
A7-A1
Parallel Port
A7-A0
ID
xx00000
xxx00000
R
Analog Loopback
ALOOP
xx00001
xxx00001
R/W
Remote Loopback
RLOOP
xx00010
xxx00010
R/W
TAOS Enable
TAOS
xx00011
xxx00011
R/W
LOS Status Monitor
LOS
xx00100
xxx00100
R
DFM Status Monitor
DFM
xx00101
xxx00101
R
LOS Interrupt Enable
LIE
xx00110
xxx00110
R/W
DFM Interrupt Enable
DIE
xx00111
xxx00111
R/W
LOS Interrupt Status
LIS
xx01000
xxx01000
R
DFM Interrupt Status
DIS
xx01001
xxx01001
R
Software Reset Register
RES
xx01010
xxx01010
R/W
Performance Monitoring
MON
xx01011
xxx01011
R/W
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 6.
Serial and Parallel Port Register Addresses (Sheet 2 of 2)
Address
Name
Table 7.
Symbol
Serial Port
A7-A1
Parallel Port
A7-A0
Digital Loopback
DL
xx01100
xxx01100
R/W
LOS/AIS Criteria Selection
LOSC
xx01101
xxx01101
R/W
Automatic TAOS Select
ATS
xx01110
xxx01110
R/W
Global Control Register
GCR
xx01111
xxx01111
R/W
Pulse Shaping Indirect Address Register
PSIAD
xx10000
xxx10000
R/W
Pulse Shaping Data Register
PSDAT
xx10001
xxx10001
R/W
Output Enable Register
OER
xx10010
xxx10010
R/W
AIS Status Register
AIS
xx10011
xxx10011
R
AIS Interrupt Enable
AISIE
xx10100
xxx10100
R/W
AIS Interrupt Status
AISIS
xx10101
xxx10101
R
Register Bit Names (Sheet 1 of 2)
Register
Name
ID Register
Bit
Sym
RW
ID
R
7
6
5
4
3
2
1
0
ID7
ID6
ID5
ID4
ID3
ID2
ID1
ID0
ALOOP R/W
AL7
AL6
AL5
AL4
AL3
AL2
AL1
AL0
Remote Loopback RLOOP R/W
RL7
RL6
RL5
RL4
RL3
RL2
RL1
RL0
TAOS2
TAOS1
TAOS0
Analog Loopback
TAOS Enable
TAOS R/W TAOS7
TAOS6 TAOS5 TAOS4 TAOS3
LOS Status
Monitor
LOS
R
LOS7
LOS6
LOS5
LOS4
LOS3
LOS2
LOS1
LOS0
DFM Status
Monitor
DFM
R
DFM7
DFM6
DFM5
DFM4
DFM3
DFM2
DFM1
DFM0
LOS Interrupt
Enable
LIE
R/W
LIE7
LIE6
LIE5
LIE4
LIE3
LIE2
LIE1
LIE0
DFM Interrupt
Enable
DIE
R/W
DIE7
DIE6
DIE5
DIE4
DIE3
DIE2
DIE1
DIE0
LOS Interrupt
Status
LIS
R
LIS7
LIS6
LIS5
LIS4
LIS3
LIS2
LIS1
LIS0
DFM Interrupt
Status
DIS
R
DIS7
DIS6
DIS5
DIS4
DIS3
DIS2
DIS1
DIS0
Software Reset
Register
RES
R/W
RES7
RES6
RES5
RES4
RES3
RES2
RES1
RES0
Performance
Monitoring
MON
R/W
Reserved
Reserved
A3
A2
A1
A0
DL
R/W
DL7
DL6
DL3
DL2
DL1
DL0
LACS2
LACS1
LACS0
ATS2
ATS1
ATS0
Digital Loopback
LOS/AIS Criteria
Select
Automatic TAOS
Select
Datasheet
Mode
LACS R/W LACS7
ATS
R/W
ATS7
Reserved Reserved
DL5
DL4
LACS6 LACS5 LACS4 LACS3
ATS6
ATS5
ATS4
ATS3
39
LXT384 — Octal T1/E1/J1 Transceiver
Table 7.
Register Bit Names (Sheet 2 of 2)
Register
Name
Sym
RW
7
GCR
R/W
Reserved
Pulse Shaping
Indirect Address
Register
PSIAD R/W
Reserved
Reserved
Reserved Reserved
Reserved
Pulse Shaping
Data Register
PSDAT R/W
Reserved
Reserved
Reserved Reserved
Reserved
LEN2
LEN1
LEN0
Global Control
Register
Table 8.
Bit
6
5
4
3
RAISEN CDIS CODEN FIFO64
2
JACF
1
0
JASEL1 JASEL0
LENAD2 LENAD1 LENAD0
Output Enable
Register
OER
R/W
OE7
OE6
OE5
OE4
OE3
OE2
OE1
OE0
AIS Status
Register
AIS
R
AIS7
AIS6
AIS5
AIS4
AIS3
AIS2
AIS1
AIS0
AIS Interrupt
Enable
AISIE
R/W
AISIE7
AISIE6 AISIE5 AISIE4 AISIE3
AISIE2
AISIE1
AISIE0
AIS Interrupt
Status
AISIS
R
AISIS7
AISIS6 AISIS5 AISIS4 AISIS3
AISIS2
AISIS1
AISIS0
ID Register, ID (00h)
Bit
Name
7-0
ID7-ID0
Function
This register contains a unique revision code and is mask programmed.
For Rev. A4, 00h
For Rev. A5, 15h
Table 9.
Analog Loopback Register, ALOOP (01h)
Bit
Name
7-0
AL7-AL0
Function
Setting a bit to “1” enables analog local loopback for transceivers 7- 0 respectively.
Table 10. Remote Loopback Register, RLOOP (02h)
Bit
Name
7-0
RL7-RL0
Function
Setting a bit to “1” enables remote loopback for transceivers 7-0 respectively.
Table 11. TAOS Enable Register, TAOS (03h)
Bit1
Name
Function2
7-0
TAOS7-TAOS0
Setting a bit to “1” causes a continuous stream of marks to be sent out at the TTIP and
TRING pins of the respective transceiver 7-0.
1. On power up all register bits are set to “0”.
2. MCLK is used as timing reference. If MCLK is not available then the channel TCLK is used as the
reference.This feature is not available in data recovery and line driver mode (MCLK= High and TCLK =
High).
40
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 12. LOS Status Monitor Register, LOS (04h)
Bit1
Name
7-0
LOS7-LOS0
Function
Respective bit(s) are set to “1” every time the LOS processor detects a valid loss of
signal condition in transceivers 7-0.
1. On power up all register bits are set to “0”. Any change in the state causes an interrupt. All LOS interrupts
are cleared by a single read operation.
Table 13. DFM Status Monitor Register, DFM (05h)
Bit
Name
7-0
DFM7-DFM0
Function1
Respective bit(s) are set to “1” every time the short circuit monitor detects a valid
secondary output driver short circuit condition in transceivers 7-0. Note: DFM is
available only in configurations with no transmit series resistors (T1 mode with
TVCC=3.3V).
1. On power-up all the register bits are set to “0”. All DFM interrupts are cleared by a single read operation.
Table 14. LOS Interrupt Enable Register, LIE (06h)
Bit
Name
7-0
LIE7-LIE0
Function1
Transceiver 7-0 LOS interrupts are enabled by writing a “1” to the respective bit.
1. On power-up all the register bits are set to “0” and all interrupts are disabled.
Table 15. DFM Interrupt Enable Register, DIE (07h)
Bit
Name
7-0
DIE7-DIE0
Function1
Transceiver 7-0 DFM interrupts are enabled by writing a “1” to the respective bit.
1. On power-up all the register bits are set to “0” and all interrupts are disabled.
Table 16. LOS Interrupt Status Register, LIS (08h)
Bit
Name
7-0
LIS7-LIS0
Function1
These bits are set to “1” every time a LOS status change has occurred since the last
cleared interrupt in transceivers 7-0 respectively.
1. On power up all register bits are set to “0”.
Table 17. DFM Interrupt Status Register, DIS (09h)
Bit
Name
Function1
7-0
DIS7-DIS0
These bits are set to “1” every time a DFM status change has occurred since the last
cleared interrupt in transceivers 7-0 respectively.
1. On power up all register bits are set to “0”.
Datasheet
41
LXT384 — Octal T1/E1/J1 Transceiver
Table 18. Software Reset Register, RES (0Ah)
Bit
Name
7-0
RES7-RES0
Function
Writing to this register initiates a 1 microsecond reset cycle, except in Intel nonmultiplexed mode. This operation sets all LXT384 registers to their default values.
When using Intel non-multiplexed host mode, extend cycle time to 2 microseconds.
Please refer to Host Mode section for details.
Table 19. Performance Monitoring Register, MON (0Bh)
Bit
Name
3-0
A3:A0
4-7
reserved
Function
Protected Monitoring selection. See Table 1, page 15.
Reserved.
Table 20. Digital Loopback Register, DL (0Ch)
Bit1
Name
7-0
DL7-DL0
Function2
Setting a bit to “1” enables digital loopback for the respective transceiver.
1. On power up all register bits are set to “0”.
2. During digital loopback LOS and TAOS stay active and independent of TCLK, while data received on
TPOS/TNEG/CKLK is looped back to RPOS/RNEG/RCLK.
Table 21. LOS/AIS Criteria Register, LCS (0Dh)
Bit1
Function2
Name
T1 Mode
Don’t care. T1.231 compliant LOS/AIS detection is used.
7-0
LCS7-LCS0
E1 Mode
Setting a bit to “1” selects the ETSI 300233 LOS. Setting a bit to “0” selects G.775
LOS mode. AIS works correctly for both ETSI and ITU when the bit is cleared to “0”.
See errata 10.3 or higher for a way to implement ETSI LOS and AIS.
1. On power-on reset the register is set to “0”.
2. T1 or E1 operation mode is determined by the PSDAT settings.
Table 22. Automatic TAOS Select Register, ATS (0Eh)
Bit1
Name
7-0
ATS7-ATS0
Function
Setting a bit to “1” enables automatic TAOS generation whenever a LOS condition is
detected in the respective transceiver.
1. On power-on reset the register is set to “0”.
2. This feature is not available in data recovery and line driver mode (MCLK= High and TCLK = High).
42
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 23. Global Control Register, GCR (0Fh)
Bit1
Name
0
JASEL0
1
Function
These bits determine the jitter attenuator position:
JASEL0
JASEL1
JA Position
1
0
Transmit Path
1
1
Receive Path
0
x
Disabled
JASEL1
2
JACF
3
FIFO64
4
CODEN
5
CDIS
This bit determines the jitter attenuator low limit 3dB corner frequency. Refer to the
Jitter Attenuator specifications for details. See Table 42 on page 59.
This bit determines the jitter attenuator FIFO depth:
0 = 32 bit
1 = 64 bit
This bit selects the zero suppression code for unipolar operation mode:
0 = B8ZS/HDB3 (T1/E1 respectively)
1 = AMI
This bit controls enables/disables the short circuit protection feature:
0 = enabled
1 = disabled
This bit controls automatic AIS insertion in the receive path when LOS occurs:
6
RAISEN
0 = Receive AIS insertion disabled on LOS
1 = RPOS/RNEG = AIS on LOS
Note: this feature is not available in data recovery mode (MCLK=High). Disable AIS
interrupts when changing this bit value to prevent inadvertent interrupts.
7
-
Reserved.
1. On power-on reset the register is set to “0”.
Table 24. Pulse Shaping Indirect Address Register, PSIAD (10h)
Bit1
Name
Function
The three bit value written to these bits determine the channel to be addressed. Data
can be read from (written to) the Pulse Shaping Data Register (PSDAT).
LENAD 0-2
0-2
37
LENAD 0-2
-
Channel
LENAD 0-2
Channel
0h
0
4h
4
1h
1
5h
5
2h
2
6h
6
3h
3
7h
7
Reserved.
1. On power-on reset the register is set to “0”.
Datasheet
43
LXT384 — Octal T1/E1/J1 Transceiver
Table 25. Pulse Shaping Data Register, PSDAT (11h)
Bit
Name
Function
LEN0-2 determine the LXT384 operation mode: T1 or E1. In addition, for T1 operation,
LEN2-0 set the pulse shaping to meet the T1.102 pulse template at the DSX-1 crossconnect point for various cable lengths:
0-2
37
LEN 0-21, 3
-
Line Length
Cable Loss2
LEN2
LEN1
LEN0
0
1
1
0 - 133 ft. ABAM
0.6 dB
1
0
0
133 - 266 ft. ABAM
1.2 dB
1
0
1
266 - 399 ft. ABAM
1.8 dB
1
1
0
399 - 533 ft. ABAM
2.4 dB
1
1
1
533 - 655 ft. ABAM
3.0 dB
0
0
0
E1 G.703, 75Ω coaxial cable and 120Ω
twisted pair cable.
Operation
Mode
T1
E1
Reserved.
1. On power-on reset the register is set to “0”.
2. Maximum cable loss at 772 KHz.
3. When reading LEN, bit values appear inverted. “B2” revision silicon will fix this so the bits read back
correctly.
Table 26. Output Enable Register, OER (12h)
Bit1
Name
7-0
OE7 - OE0
Function
Setting a bit to “1” tristates the output driver of the corresponding transceiver.
1. On power-up all the register bits are set to “0”.
Table 27. AIS Status Monitor Register, AIS (13h)
Bit1
Name
7-0
AIS7-AIS0
Function
Respective bit(s) are set to “1” every time the receiver detects a AIS condition in
transceivers 7-0.
1. On power-up all the register bits are set to “0”. All AIS interrupts are cleared by a single read operation.
Table 28. AIS Interrupt Enable Register, AISIE (14h)
Bit1
Name
7-0
AISIE7-AISIE0
Function
Transceiver 7-0 AIS interrupts are enabled by writing a “1” to the respective bit.
1. On power-up all the register bits are set to “0”.
44
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 29. AIS Interrupt Status Register, AISIS (15h)
Bit1
Name
7-0
AISIS7-AISIS0
Function
These bits are set to “1” every time a AIS status change has occurred since the last
clear interrupt in transceivers 7-0 respectively.
1. On power-up all the register bits are set to “0”.
4.0
JTAG Boundary Scan
4.1
Overview
The LXT384 supports IEEE 1149.1 compliant JTAG boundary scan. Boundary scan allows easy
access to the interface pins for board testing purposes.
In addition to the traditional IEE1149.1 digital boundary scan capabilities, the LXT384 also
includes analog test port capabilities. This feature provides access to the TIP and RING signals in
each channel (transmit and receive). This way, the signal path integrity across the primary winding
of each coupling transformer can be tested.
4.2
Architecture
The basic JTAG architecture of the LXT384 is illustrated in Figure 15.
The LXT384 JTAG architecture includes a TAP Test Access Port Controller, data registers and an
instruction register. The following paragraphs describe these blocks in detail.
Datasheet
45
LXT384 — Octal T1/E1/J1 Transceiver
Figure 15. JTAG Architecture
Boundry Scan Data Register
BSR
Analog Port Scan Register
ASR
Device Identification Register
IDR
TDI
MUX
TDO
Bypass Register
BYR
Instruction Register
IR
TCK
TAP
Controller
TMS
TRST
4.3
TAP Controller
The TAP controller is a 16 state synchronous state machine controlled by the TMS input and
clocked by TCK (see Figure 16).The TAP controls whether the LXT384 is in reset mode, receiving
an instruction, receiving data, transmitting data or in an idle state. Table 30 describes in detail each
of the states represented in Figure 16.
Table 30. TAP State Description (Sheet 1 of 2)
46
State
Description
Test Logic Reset
In this state the test logic is disabled. The device is set to normal operation mode. While in
this state, the instruction register is set to the ICODE instruction.
Run -Test / Idle
The TAP controller stays in this state as long as TMS is Low. Used to perform tests.
Capture - DR
The Boundary Scan Data Register (BSR) is loaded with input pin data.
Shift - DR
Shifts the selected test data registers by one stage tword its serial output.
Update - DR
Data is latched into the parallel output of the BSR when selected.
Capture - IR
Used to load the instruction register with a fixed instruction.
Shift - IR
Shifts the instruction register by one stage.
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 30. TAP State Description (Sheet 2 of 2)
Datasheet
State
Description
Update - IR
Loads a new instruction into the instruction register.
Pause - IR
Pause - DR
Momentarily pauses shifting of data through the data/instruction registers.
Exit1 - IR
Exit1 - DR
Exit2 - IR
Exit2 - DR
Temporary states that can be used to terminate the scanning process.
47
LXT384 — Octal T1/E1/J1 Transceiver
Figure 16. JTAG State Diagram
1
TEST-LOGIC
RESET
0
0
RUN TEST/IDLE
1
SELECT-DR
1
SELECT-IR
0
1
0
1
CAPTURE-DR
CAPTURE-IR
0
0
0
0
SHIFT-DR
SHIFT-IR
1
1
EXIT1-DR
1
EXIT1-IR
0
0
0
PAUSE-IR
1
1
EXIT2-DR
0
EXIT2-IR
1
0
UPDATE-DR
1
4.4
1
0
PAUSE-DR
0
1
0
UPDATE-IR
1
0
JTAG Register Description
The following paragraphs describe each of the registers represented in Figure 15.
48
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
4.4.1
Boundary Scan Register (BSR)
The BSR is a shift register that provides access to all the digital I/O pins. The BSR is used to apply
and read test patterns to/from the board. Each pin is associated with a scan cell in the BSR register.
Bidirectional pins or tristatable pins require more than one position in the register. Table 31 shows
the BSR scan cells and their functions. Data into the BSR is shifted in LSB first.
The Analog Test Port can be used to verify continuity across the coupling transformer’s primary
winding as shown in Figure 17. By applying a stimulus to the AT1 input, a known voltage will
appear at AT2 for a given load. This, in effect, tests the continuity of a receive or transmit interface.
Table 31. Boundary Scan Register (BSR) (Sheet 1 of 4)
Bit #
Pin
Signal
I/O Type
Bit
Symbol
0
LOOP0
I/O
PADD0
1
LOOP0
I/O
PDO0
2
LOOP1
I/O
PADD1
3
LOOP1
I/O
PDO1
4
LOOP2
I/O
PADD2
5
LOOP2
I/O
PDO2
6
LOOP3
I/O
PADD3
7
LOOP3
I/O
PDO3
8
LOOP4
I/O
PADD4
9
LOOP4
I/O
PDO4
10
LOOP5
I/O
PADD5
11
LOOP5
I/O
PDO5
12
LOOP6
I/O
PADD6
13
LOOP6
I/O
PDO6
14
LOOP7
I/O
PADD7
Comments
PDOENB controls the LOOP0 through LOOP7 pins.
15
N/A
-
PDOENB
Setting PDOENB to “0” configures the pins as outputs. The
output value to the pin is set in PDO[0..7].
Setting PDOENB to “1” tristates all the pins. The input value
to the pins can be read in PADD[0..7].
16
Datasheet
LOOP7
I/O
PDO7
17
TCLK1
I
TCLK1
18
TPOS1
I
TPOS1
19
TNEG1
I
TNEG1
20
RCLK1
O
RCLK1
21
RPOS1
O
RPOS1
22
N/A
-
HIZ1
23
RNEG1
O
RNEG1
24
LOS1
O
LOS1
HIZ1 controls the RPOS1, RNEG1 and RCLK1 pins. Setting
HIZ1 to “0” enables output on the pins. Setting HIZ1 to “1”
tristates the pins.
49
LXT384 — Octal T1/E1/J1 Transceiver
Table 31. Boundary Scan Register (BSR) (Sheet 2 of 4)
50
Bit #
Pin
Signal
I/O Type
Bit
Symbol
25
TCLK0
I
TCLK0
26
TPOS0
I
TPOS0
27
TNEG0
I
TNEG0
28
RCLK0
O
RCLK0
29
RPOS0
O
RPOS0
30
N/A
-
HIZ0
31
RNEG0
O
RNEG0
32
LOS0
O
LOS0
33
MUX
I
MUX
34
LOS3
O
LOS3
35
RNEG3
O
RNEG3
36
N/A
-
HIZ3
37
RPOS3
O
RPOS3
38
RCLK3
O
RCLK3
39
TNEG3
I
TNEG3
40
TPOS3
I
TPOS3
41
TCLK3
I
TCLK3
42
LOS2
O
LOS2
43
RNEG2
O
RNEG2
44
N/A
-
HIZ2
45
RPOS2
O
RPOS2
46
RCLK2
O
RCLK2
47
TNEG2
I
TNEG2
48
TPOS2
I
TPOS2
49
TCLK2
I
TCLK2
50
INT
O
INT
51
N/A
-
SDOACKENB
52
ACK
O
ACK
53
DS
I
WRB
54
R/W
I
RDB
55
ALE
I
ALE
56
CS
I
CSB
Comments
HIZ0 controls the RPOS0, RNEG0 and RCLK0 pins. Setting
HIZ0 to “0” enables output on the pins. Setting HIZ0 to “1”
tristates the pins.
HIZ3 controls the RPOS3, RNEG3 and RCLK3 pins. Setting
HIZ3 to “0” enables output on the pins. Setting HIZ3 to “1”
tristates the pins.
HIZ2 controls the RPOS2, RNEG2 and RCLK2 pins. Setting
HIZ2 to “0” enables output on the pins. Setting HIZ2 to “1”
tristates the pins.
SDOACKENB controls the ACK pin. Setting SDOACKEN to
“0” enables output on ACK pin. Setting SDOACKEN to “1”
tristates the pin.
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 31. Boundary Scan Register (BSR) (Sheet 3 of 4)
Datasheet
Bit #
Pin
Signal
I/O Type
Bit
Symbol
57
MOT/INTL
I
MOTO
58
TCLK5
I
TCLK5
59
TPOS5
I
TPOS5
60
TNEG5
I
TNEG5
61
RCLK5
O
RCLK5
62
RPOS5
O
RPOS5
63
N/A
-
HIZ5
64
RNEG5
O
RNEG5
65
LOS5
O
LOS5
66
TCLK4
I
TCLK4
67
TPOS4
I
TPOS4
68
TNEG4
I
TNEG4
69
RCLK4
O
RCLK4
70
RPOS4
O
RPOS4
71
N/A
-
HIZ4
72
RNEG4
O
RNEG4
73
LOS4
O
LOS4
74
OE
I
OE
75
CLKE
I
CLKE
76
LOS7
O
LOS7
77
RNEG7
O
RNEG7
78
N/A
-
HIZ7
79
RPOS7
O
RPOS7
80
RCLK7
O
RCLK7
81
TNEG7
I
TNEG7
82
TPOS7
I
TPOS7
83
TCLK7
I
TCLK7
84
LOS6
O
LOS6
85
RNEG6
O
RNEG6
86
N/A
-
HIZ6
87
RPOS6
O
RPOS6
88
RCLK6
O
RCLK6
Comments
HIZ5 controls the RPOS5, RNEG5 and RCLK5 pins. Setting
HIZ5 to “0” enables output on the pins. Setting HIZ5 to “1”
tristates the pins.
HIZ4 controls the RPOS4, RNEG4 and RCLK4 pins. Setting
HIZ4 to “0” enables output on the pins. Setting HIZ4 to “1”
tristates the pins.
HIZ7 controls the RPOS7, RNEG7 and RCLK7 pins. Setting
HIZ7 to “0” enables output on the pins. Setting HIZ7 to “1”
tristates the pins.
HIZ6 controls the RPOS6, RNEG6 and RCLK6 pins. Setting
HIZ6 to “0” enables output on the pins. Setting HIZ6 to “1”
tristates the pins.
51
LXT384 — Octal T1/E1/J1 Transceiver
Table 31. Boundary Scan Register (BSR) (Sheet 4 of 4)
4.4.2
Bit #
Pin
Signal
I/O Type
Bit
Symbol
89
TNEG6
I
TNEG6
90
TPOS6
I
TPOS6
91
TCLK6
I
TCLK6
92
MCLK
I
MCLK
93
MODE
I
MODE
94
A4
I
A4
95
A3
I
A3
96
A2
I
A2
97
A1
I
A1
98
A0
I
A0
Comments
Analog Port Scan Register (ASR)
The ASR is a 5 bit shift register used to control the analog test port at pins AT1, AT2. When the
INTEST_ANALOG instruction is selected, TDI connects to the ASR input and TDO connects to
the ASR output. After 5 TCK rising edges, a 5 bit control code is loaded into the ASR. Data into
the ASR is shifted in LSB first.
Table 32 shows the 16 possible control codes and the corresponding operation on the analog port.
Table 32. Analog Port Scan Register (ASR)
52
ASR Control Code
AT1 Forces Voltage To:
AT2 Senses Voltage From:
11111
TTIP0
TRING0
11110
TTIP1
TRING1
11101
TTIP2
TRING2
11100
TTIP3
TRING3
11011
TTIP4
TRING4
11010
TTIP5
TRING5
11001
TTIP6
TRING6
11000
TTIP7
TRING7
10111
RTIP0
RRING0
10110
RTIP1
RRING1
10101
RTIP2
RRING2
10100
RTIP3
RRING3
10011
RTIP4
RRING4
10010
RTIP5
RRING5
10001
RTIP6
RRING6
10000
RTIP7
RRING7
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Figure 17. Analog Test Port Application
JTAG Port
ASR Register
RTIP7
Transceiver 7
RRING7
TTIP7
TRING7
RTIP6
Analog Mux
RRING6
TTIP6
TRING6
1K
Transceiver 6
RTIP0
Transceiver 0
RRING0
1K
AT2
AT1
4.4.3
Device Identification Register (IDR)
The IDR register provides access to the manufacturer number, part number and the LXT384
revision. The register is arranged per IEEE 1149.1 and is represented in Table 33. Data into the IDR
is shifted in LSB first.
Table 33. Device Identification Register (IDR)
Bit #
31 - 28
Revision number
27 - 12
Part number
11 - 1
0
4.4.4
Comments
Manufacturer number
Set to “1”
Bypass Register (BYR)
The Bypass Register is a 1 bit register that allows direct connection between the TDI input and the
TDO output.
4.4.5
Instruction Register (IR)
The IR is a 3 bit shift register that loads the instruction to be performed. The instructions are shifted
LSB first. Table 34 shows the valid instruction codes and the corresponding instruction description.
Datasheet
53
LXT384 — Octal T1/E1/J1 Transceiver
Table 34. Instruction Register (IR)
5.0
Instruction
Code #
Comments
EXTEST
000
Connects the BSR to TDI and TDO. Input pins values are loaded into the
BSR. Output pins values are loaded from the BSR.
INTEST_ANALOG
010
Connects the ASR to TDI and TDO. Allows voltage forcing/sensing through
AT1 and AT2. Refer to Table 32.
SAMPLE / PRELOAD
100
Connects the BSR to TDI and TDO. The normal path between the LXT384
logic and the I/O pins is maintained. The BSR is loaded with the signals in
the I/O pins.
IDCODE
110
Connects the IDR to the TDO pin.
BYPASS
111
Serial data from the TDI input is passed to the TDO output through the 1 bit
Bypass Register.
Test Specifications
Note:
Table 35 through Table 54 and Figure 18 through Figure 35 represent the performance
specifications of the LXT384 and are guaranteed by test except, where noted, by design. The
minimum and maximum values listed in Table 37 through Table 54 are guaranteed over the
recommended operating conditions specified in Table 36.
Table 35. Absolute Maximum Ratings
Parameter
Symbol
Min.
Max
Unit
DC supply voltage
Vcc0, Vcc1,
Vccio0, Vccio1
-0.5
4.0
V
DC supply voltage
Tvcc 0-7
-0.5
7.0
V
Input voltage on any digital pin
Vin
GND-0.5
5.5
V
Input voltage on RTIP, RRING1
Vin
GND-0.5
VCC0 + 0.5
VCC1 + 0.5
V
ESD voltage on any Pin 2
Vin
2000
–
V
Transient latch-up current on any pin
Iin
100
mA
Input current on any digital pin 3
Iin
-10
10
mA
DC input current on TTIP, TRING 3
Iin
–
±100
mA
3
Iin
–
±100
mA
Tstor
-65
DC input current on RTIP, RRING
+150
°C
PP
1.6
W
Case Temperature, 144 pin LQFP package
Tcase
120
°C
Case Temperature, 160 pin PBGA package
Tcase
120
°C
Storage temperature
Maximum power dissipation in package
Caution: Exceeding these values may cause permanent damage. Functional operation under these
conditions is not implied. Exposure to absolute maximum rating conditions for extended periods may
affect device reliability.
1. Referenced to ground.
2. Human body model.
3. Constant input current.
54
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 36. Recommended Operating Conditions
Parameter
LEN
Sym
Min.
Typ
Max
Unit
Test Condition
Digital supply voltage (VCC and VCCIO)
-
VCC
3.135
3.3
3.465
V
3.3V ± 5%
Transmitter supply voltage, TVCC=5V
nominal
-
TVCC
4.75
5.0
5.25
V
5V ± 5%
Transmitter supply voltage, TVCC=3.3V
nominal
-
TVCC
3.135
3.3
3.465
V
3.3V ± 5%
Ambient operating temperature
-
Ta
-40
25
+85
°C
ITVCC
-
440
490
mA
100% 1’s density
230
-
mA
50% 1’s density
IVCC
-
90
120
mA
Rl
25
–
–
Ω
Typ
Max1
Unit
Test Conditions
Average transmitter power supply current,
T1 Mode 1, 2
Average digital power
supply current 1, 3
Output load at TTIP and
TRING
Device Power Consumption
Mode
E1
T12
E1
T12
TVCC
Load
LEN
75 Ω
000
120 Ω
000
-
-
760
-
mW
50% 1’s
-
-
1270
1420
mW
100% 1’s
-
-
640
-
mW
50% 1’s
-
-
1110
1280
mW
100% 1’s
-
-
1020
-
mW
50% 1’s
-
-
1820
2100
mW
100% 1’s
-
-
1000
-
mW
50% 1’s
-
-
1730
1940
mW
100% 1’s
-
-
820
-
mW
50% 1’s
-
-
1500
1730
mW
100% 1’s
-
-
1400
-
mW
50% 1’s
-
-
2670
2960
mW
100% 1’s
3.3V
3.3V
100 Ω
101-111
75 Ω
000
5.0V
5.0V
120 Ω
000
100 Ω
101-111
1. Current consumption over the full operating temperature and power supply voltage range. Includes all
channels.
2. T1 maximum values measured with maximum cable length (LEN = 111). Typical values measured with
typical cable length (LEN = 101).
3. Digital inputs are within 10% of the supply rails and digital outputs are driving a 50pF load.
Table 37. DC Characteristics (Sheet 1 of 2)
Parameter
Sym
Min.
Typ
Max
Unit
VIH
2
–
–
V
VIL
–
–
0.8
V
High level output voltage
VOH
2.4
–
VCCIO
V
IOUT= 400µA
1
VOL
–
–
0.4
V
IOUT= 1.6mA
High level input voltage
Low level input voltage
1
Low level output voltage
Test Condition
1. Output drivers will output CMOS logic levels into CMOS loads.
Datasheet
55
LXT384 — Octal T1/E1/J1 Transceiver
Table 37. DC Characteristics (Sheet 2 of 2)
Parameter
Sym
Min.
Typ
Max
Unit
Vinl
–
–
1/3VCC-0.2
V
Midrange level input
voltage
Vinm
1/3VCC+0.2
1/2VCC
2/3VCC-0.2
V
High level input
voltage
Vinh
2/3VCC+0.2
–
–
V
Low level input
current
Iinl
–
–
50
µA
High level input
current
Iinh
–
–
50
µA
Low level input
voltage
MODE,
LOOP0-7
and
JASEL
Input leakage current
Iil
-10
+10
µA
Tri state leakage current
Ihz
-10
+10
µA
Tri state output current
Ihz
–
–
1
µA
–
–
–
50
TMS
TDI
TRST
–
–
50
Line short circuit current
Input leakage
mA
RMS
Test Condition
The VCC supply
refers to VCC0 or
VCC1 only.
TTIP, TRING
2 x 11 Ω series
resistors and 1:2
transformer
µA
1. Output drivers will output CMOS logic levels into CMOS loads.
Table 38. E1 Transmit Transmission Characteristics (Sheet 1 of 2)
Parameter
Output pulse
amplitude
Peak voltage of a
space
75Ω
120Ω
75Ω
120Ω
Sym
–
–
Transmit amplitude variation with supply
–
Difference between pulse sequences
–
Pulse width ratio of the positive and negative
pulses
–
Transmit transformer turns ratio for
75/120Ω characteristic impedance
Transmit return
loss 75 Ω coaxial
cable1
51kHz to 102 kHz
Transmit return
loss 120 Ω twisted
pair cable1
51kHz to 102 kHz
102 kHz to 2.048 MHz
2.048 MHz to 3.072 MHz
Typ
Max
Unit
2.14
2.37
2.60
V
2.7
3.0
3.3
V
-0.237
0.237
V
-0.3
0.3
V
-1
+1
%
200
mV
0.95
–
–
2.048 MHz to 3.072 MHz
102 kHz to 2.048 MHz
Min.
–
17
17
15
17
15
20
15
20
15
20
For 17 consecutive
pulses
Rt = 11 Ω ± 1%
1:2
15
Tested at the line side
At the nominal half
amplitude
1.05
15
Test Condition
dB
–
dB
dB
dB
–
dB
dB
Using components in
the LXD384
evaluation board.
Using components in
the LXD384
evaluation board
1. Guaranteed by design and other correlation methods.
56
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 38. E1 Transmit Transmission Characteristics (Sheet 2 of 2)
Parameter
Sym
Min.
Typ
Max
Unit
–
–
0.030
0.050
U.I.
Transmit intrinsic jitter; 20Hz to 100kHz
Transmit path
delay
Bipolar mode
2
U.I.
Unipolar mode
7
U.I.
Test Condition
Tx path TCLK is jitter
free
JA Disabled
1. Guaranteed by design and other correlation methods.
Table 39. E1 Receive Transmission Characteristics
Parameter
Permissible cable attenuation
Sym
Min.
Typ
Max
Unit
Test Condition
–
–
–
12
dB
Receiver dynamic range
DR
0.5
–
–
Vp
Signal to noise interference margin
S/I
-15
–
–
dB
Per G.703, O.151 @ 6
dB cable Attenuation
SRE
43
50
57
%
Rel. to peak input
voltage
Data slicer threshold
–
–
150
–
mV
Loss of signal threshold
–
–
200
–
mV
LOS hysteresis
–
–
50
–
mV
Data decision threshold
Consecutive zeros before loss of signal
–
–
LOS reset
–
12.5%
Low limit
1Hz to 20Hz
input jitter
20Hz to 2.4kHz
tolerance 1
18kHz to 100kHz
32
2048
–
–
–
–
–
36
–
1.5
–
–
0.2
Note 1
U.I.
Cable Attenuation is 6
dB
@1.024 MHz
–
70
–
kΩ
–
–
–
±1
%
Common mode input impedance to ground
–
–
20
–
kΩ
102 - 2048 kHz
–
2048kHz - 3072 kHz
dB
20
–
20
1’s density
U.I.
–
20
ETSI 300 233
specification
U.I.
Input termination resistor tolerance
51 kHz - 102 kHz
G.775
recommendation
G735
recommendation
Differential receiver input impedance
Input return
loss1
@1024 kHz
dB
dB
Measured against
nominal impedance
using components in
the LXD384
evaluation board.
LOS delay time
–
–
30
–
µs
Data recovery mode
LOS reset
–
10
–
255
marks
Data recovery mode
Receive intrinsic jitter, RCLK output
–
–
0.040
0.0625
U.I.
Receive
path delay
Bipolar mode
1
U.I.
Unipolar mode
6
U.I.
Wide band jitter
JA Disabled
1. Guaranteed by design and other correlation methods.
Datasheet
57
LXT384 — Octal T1/E1/J1 Transceiver
Table 40. T1 Transmit Transmission Characteristics
Parameter
Sym
Min.
Typ
Max
Unit
Test Condition
Output pulse amplitude
–
2.4
3.0
3.6
V
Peak voltage of a space
–
-0.15
–
+0.15
V
Driver output impedance1
–
–
1
–
Ω
Transmit amplitude variation with power
supply
–
-1
–
+1
%
Ratio of positive to negative pulse amplitude
–
0.95
–
1.05
–
T1.102, isolated pulse
Difference between pulse sequences
–
–
–
200
mV
Pulse width variation at half amplitude
–
–
–
20
ns
For 17 consecutive
pulses, GR-499-CORE
8KHz - 40KHz
–
10Hz - 40KHz
–
–
@ 772 KHz
–
@ 1544 KHz
12.6
-29
UIpk-pk
–
17.9
dBm
dBm
21
15
21
15
21
dB
Bipolar mode
2
U.I.
Unipolar mode
7
U.I.
102 kHz to 2.048 MHz
–
2.048 MHz to 3.072 MHz
Transmit path
delay
0.025
15
51kHz to 102 kHz
Transmit Return
Loss 1
0.025
AT&T Pub 62411
TCLK is jitter free
0.050
Wide Band
Output power
levels2
@ 772 KHz
0.020
10Hz - 8KHz
Jitter added by
Transmitter1
Measured at the DSX
dB
–
dB
T1.102 - 1993
Referenced to power at
772 KHz
With transmit series
resistors (TVCC=5V).
Using components in
the LXD384 evaluation
board.
JA Disabled
1. Guaranteed by design and other correlation methods.
2. Power measured in a 3 KHz bandwidth at the point the signal arrives at the distribution frame for an all 1’s
pattern.
Table 41. T1 Receive Transmission Characteristics (Sheet 1 of 2)
Parameter
Permissible cable attenuation
Sym
Min.
Typ
Max
Unit
Test Condition
–
–
–
12
dB
Receiver dynamic range
DR
0.5
–
–
Vp
Signal to noise interference margin
S/I
-16.5
–
–
dB
@ 655 ft. of 22 ABAM
cable
SRE
63
70
77
%
Rel. to peak input
voltage
Data slicer threshold
–
–
150
–
mV
Loss of signal threshold
–
–
200
–
mV
Data decision threshold
@ 772 KHz
LOS hysteresis
–
–
50
–
mV
Consecutive zeros before loss of signal
–
100
175
250
–
T1.231 - 1993
LOS reset
–
12.5%
–
–
–
1’s density
1. Guaranteed by design and other correlation methods.
58
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 41. T1 Receive Transmission Characteristics (Sheet 2 of 2)
Parameter
Sym
Low limit
0.1Hz to 1Hz
input jitter
4.9Hz to 300Hz
tolerance 1
10KHz to 100KHz
Min.
-
-
0.4
-
Input termination resistor tolerance
-
-
Common mode input impedance to ground
-
-
51 KHz - 102 KHz
-
70
20
-
kΩ
±1
%
-
kΩ
-
-
20
LOS delay time
LOS reset
1
Receive intrinsic jitter, RCLK output
U.I.
dB
20
2048 KHz - 3072 KHz
Test Condition
AT&T Pub. 62411
U.I.
20
102 - 2048 KHz
Unit
U.I.
28
-
Receive
path delay
Max
138
-
Differential receiver input impedance
Input return
loss1
Typ
dB
dB
@772 kHz
Measured against
nominal impedance.
Using components in
the LXD384 evaluation
board.
-
-
30
-
µs
Data recovery mode
-
10
-
255
-
Data recovery mode
-
-
0.035
0.0625
U.I.
Bipolar mode
1
U.I.
Unipolar mode
6
U.I.
Wide band jitter
JA Disabled
1. Guaranteed by design and other correlation methods.
Table 42. Jitter Attenuator Characteristics (Sheet 1 of 2)
Parameter
Min.
Typ
Max
Unit
32bit
FIFO
-
2.5
-
Hz
64bit
FIFO
-
3.5
-
Hz
32bit
FIFO
-
2.5
-
Hz
64bit
FIFO
-
3.5
-
Hz
32bit
FIFO
-
3
-
Hz
64bit
FIFO
-
3
-
Hz
32bit
FIFO
-
6
-
Hz
64bit
FIFO
-
6
-
Hz
E1
-
3.5
-
Hz
T1
-
6
-
Hz
32bit
FIFO
-
16
-
UI
64bit
FIFO
-
32
-
UI
Test Condition
JACF=0
E1 jitter attenuator 3dB
corner frequency, host
mode1
JACF=1
Sinusoidal jitter modulation
JACF=0
T1 jitter attenuator 3dB
corner frequency, host
mode1
JACF=1
Jitter attenuator 3dB corner frequency,
hardware mode1
Data latency delay
Delay through the Jitter
attenuator only. Add receive and
transmit path delay for total
throughput delay.
1. Guaranteed by design and other correlation methods.
Datasheet
59
LXT384 — Octal T1/E1/J1 Transceiver
Table 42. Jitter Attenuator Characteristics (Sheet 2 of 2)
Parameter
Input jitter tolerance before FIFO
overflow or underflow
Min.
Typ
Max
Unit
32bit
FIFO
-
24
-
UI
64bit
FIFO
-
56
-
UI
Test Condition
E1 jitter attenuation
@ 3 Hz
@ 40 Hz
@ 400 Hz
@ 100 KHz
-0.5
-0.5
+19.5
+19.5
–
–
dB
ITU-T G.736, See Figure 34 on
page 75
T1 jitter attenuation
@ 1 Hz
@ 20 Hz
@ 1 KHz
@ 1.4 KHz
@ 70 KHz
0
0
33.3
40
40
–
–
dB
AT&T Pub. 62411, See Figure
34 on page 75
0.060
0.11
UI
ETSI CTR12/13 Output jitter
Output Jitter in remote loopback1
1. Guaranteed by design and other correlation methods.
Table 43. Analog Test Port Characteristics
Parameter
3 dB bandwidth
Sym
Min.
Typ
Max
Unit
At13db
-
5
-
MHz
V
V
Input voltage range
At1iv
0
-
VCC0
VCC1
Output voltage range
At2ov
0
-
VCC0
VCC1
Test Condition
Table 44. Transmit Timing Characteristics (Sheet 1 of 2)
Parameter
Sym
Min.
Typ
Max
Unit
E1
MCLK
–
2.048
–
MHz
T1
MCLK
–
1.544
–
MHz
Master clock tolerance
–
-100
–
100
ppm
Master clock duty cycle
–
40
–
60
%
Test Condition
Master clock frequency
E1
Tw
219
244
269
ns
T1
Tw
291
324
356
ns
E1
Tclke1
-
2.048
-
MHz
T1
Tclkt1
-
1.544
-
MHz
Output pulse width
Transmit clock frequency
Transmit clock tolerance
Tclkt
-50
–
+50
ppm
Transmit clock burst rate
Tclkb
-
–
20
MHz
Transmit clock duty cycle
Tdc
10
–
90
%
NRZ mode
Tmpwe1
236
–
252
ns
RZ mode (TCLK = H for
>16 clock cycles)
Tsut
20
-
-
ns
E1 TPOS/TNEG pulse width (RZ mode)
TPOS/TNEG to TCLK setup time
60
Gapped transmit clock
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 44. Transmit Timing Characteristics (Sheet 2 of 2)
Parameter
Sym
Min.
Typ
TCLK to TPOS/TNEG hold time
Delay time OE Low to driver High Z
Max
Unit
Tht
20
-
-
ns
Toez
-
-
1
µs
Ttz
50
60
75
µs
Delay time TCLK Low to driver High Z
Test Condition
Figure 18. Transmit Clock Timing Diagram
TCLK
tSUT
TPOS
tHT
TNEG
Table 45. Receive Timing Characteristics (Sheet 1 of 2)
Parameter
Sym
Min.
Typ
Max
Unit
E1
–
–
±80
–
ppm
Relative to nominal
frequency
T1
–
–
±180
–
ppm
MCLK = ±100 ppm
Rckd
40
50
60
%
E1
Tpw
447
488
529
ns
T1
Tpw
583
648
713
ns
E1
Tpwl
203
244
285
ns
T1
Tpwl
259
324
389
ns
E1
Tpwh
203
244
285
ns
T1
Tpwh
259
324
389
ns
Tr
20
–
–
ns
E1
Tpwdl
200
244
300
ns
T1
Tpwdl
250
324
400
ns
200
244
–
ns
200
324
–
ns
Clock recovery capture range
Receive clock duty cycle 1
Receive clock pulse width 1
Test Condition
Receive clock pulse width Low time
Receive clock pulse width High time
Rise/fall time
4
RPOS/RNEG pulse width (MCLK=H) 2
E1
RPOS/RNEG to RCLK rising setup time
@ CL=15 pF
Tsur
T1
1. RCLK duty cycle widths will vary depending on extent of received pulse jitter displacement. Maximum and
minimum RCLK duty cycles are for worst case jitter conditions (0.2UI displacement for E1 per ITU G.823).
2. Clock recovery is disabled in this mode.
3. If MCLK = H the receive PLLs are replaced by a simple EXOR circuit.
4. For all digital outputs.
Datasheet
61
LXT384 — Octal T1/E1/J1 Transceiver
Table 45. Receive Timing Characteristics (Sheet 2 of 2)
Parameter
Sym
E1
RCLK Rising to RPOS/RNEG hold time
Min.
Typ
Max
Unit
200
244
–
ns
200
324
–
ns
–
–
5
ns
Test Condition
Thr
T1
Delay time between RPOS/RNEG and RCLK
–
MCLK = H 3
1. RCLK duty cycle widths will vary depending on extent of received pulse jitter displacement. Maximum and
minimum RCLK duty cycles are for worst case jitter conditions (0.2UI displacement for E1 per ITU G.823).
2. Clock recovery is disabled in this mode.
3. If MCLK = H the receive PLLs are replaced by a simple EXOR circuit.
4. For all digital outputs.
Figure 19. Receive Clock Timing Diagram
tPW
RCLK
tPWH
tPWL
tSUR
tHR
RPOS
RNEG
CLKE = 1
tSUR
tHR
RPOS
RNEG
CLKE = 0
Table 46. JTAG Timing Characteristics
Parameter
Sym
Min.
Typ
Max
Unit
Cycle time
Tcyc
200
-
-
ns
J-TMS/J-TDI to J-TCK rising edge time
Tsut
50
-
-
ns
Tht
50
-
-
ns
Tdod
-
-
50
ns
J-CLK rising to J-TMS/L-TDI hold time
J-TCLK falling to J-TDO valid
62
Test Conditions
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Figure 20. JTAG Timing
tCYC
TCK
tSUR
tHT
TMS
TDI
tDOD
TDO
Table 47. Intel Mode Read Timing Characteristics2
Sym
Min.
Typ1
Max
Unit
Tsalr
10
–
–
ns
Valid address latch pulse width
Tvl
30
–
–
ns
Latch active to active read setup time
Tslr
10
–
–
ns
Chip select setup time to active read
Tscsr
0
–
–
ns
Chip select hold time from inactive read
Thcsr
0
–
–
ns
Address hold time from inactive ALE
Thalr
5
Active read to data valid delay time
Tprd
10
–
50
ns
Parameter
Address setup time to latch
ns
Address setup time to RD inactive
Thar
1
–
–
ns
Address hold time from RD inactive
Tsar
5
–
–
ns
Inactive read to data tri-state delay time
Tzrd
3
–
35
ns
Valid read signal pulse width
Tvrd
60
–
–
ns
Inactive read to inactive INT delay time
Test Conditions
Tint
–
–
10
ns
Active chip select to RDY delay time
Tdrdy
0
–
12
ns
Active ready Low time
Tvrdy
–
–
40
ns
Inactive ready to tri-state delay time
Trdyz
–
–
3
ns
1. Typical figures are at 25 C and are for design aid only; not guaranteed and not subject to production
testing.
2. CL= 100pF on D0-D7, all other outputs are loaded with 50pF.
Datasheet
63
LXT384 — Octal T1/E1/J1 Transceiver
Figure 21. Non-Multiplexed Intel Mode Read Timing
tSAR
ADDRESS
A4 - A0
tHAR
ALE
(pulled High)
tHCSR
tSCSR
CS
tVRD
RD
tPRD
tZRD
D7 - D0
DATA OUT
tINT
INT
tDRDY
tDRDY
tRDYZ
tVRDY
Tristate
Tristate
RDY
Figure 22. Multiplexed Intel Mode Read Timing
tVL
tSLR
ALE
tSCSR
tHSCR
CS
tVRD
tPRD
RD
tSALR
tZRD
tHALR
ADDRESS
AD7-AD0
DATA OUT
tINT
INT
tDRDY
tDRDY
Tristate
RDY
64
tVRDY
tRDYZ
Tristate
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 48. Intel Mode Write Timing Characteristics2
Parameter
Sym
Address setup time to latch
Min.
Typ1
Max
Unit
Tsalw
10
–
–
ns
Valid address latch pulse width
Tvl
30
–
–
ns
Latch active to active write setup time
Tslw
10
–
–
ns
Chip select setup time to active write
Tscsw
0
–
–
ns
Chip select hold time from inactive write
Thcsw
0
–
–
Address hold time from inactive ALE
Thalw
5
Data valid to write active setup time
Tsdw
40
–
–
ns
Data hold time to active write
Thdw
30
–
–
ns
ns
ns
Address setup time to WR inactive
Thaw
2
–
–
ns
Address hold time from WR inactive
Tsaw
6
–
–
ns
Valid write signal pulse width
Tvwr
60
–
–
ns
Tint
–
–
10
ns
Chip select to RDY delay time
Tdrdy
0
–
12
ns
Active ready Low time
Tvrdy
–
–
40
ns
Inactive ready to tri-state delay time3
Trdyz
–
–
3
ns
Inactive write to inactive INT delay time
3
Test Conditions
1. Typical figures are at 25 C and are for design aid only; not guaranteed and not subject to production
testing.
2. CL= 100pF on D0-D7, all other outputs are loaded with 50pF.
3. These times don't apply for Reset Register 0Ah, since RDY line goes low once during the cycle. Please
refer to Reset Operation and Host Mode sections for more information.
Datasheet
65
LXT384 — Octal T1/E1/J1 Transceiver
Figure 23. Non-Multiplexed Intel Mode Write Timing
tSAW
A4-A0
ALE
ADDRESS
(pulled High)
tHAW
tSCSW
tHCSW
CS
tVWR
WR
tHDW
tSDW
D7-D0
WRITE DATA
tINT
INT
tDRDY
tDRDY
tVRDY
tRDYZ
Tristate
Tristate
RDY
Figure 24. Multiplexed Intel Mode Write Timing
tSLW
ALE
tVL
tSCSW
tHCSW
CS
tVWR
WR
tHALW
tHDW
tSALW
tSDW
ADDRESS
AD7-AD0
WRITE DATA
tINT
INT
tDRDY
tDRDY
Tristate
tVRDY
tDRDYZ
Tristate
RDY
66
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 49. Motorola Bus Read Timing Characteristics2
Parameter
Sym
Min.
Typ1
Max
Unit
Address setup time to address or data strobe
Tsar
10
–
–
ns
Address hold time from address or data strobe
Thar
5
–
–
ns
Valid address strobe pulse width
Tvas
95
–
–
ns
R/W setup time to active data strobe
Tsrw
10
–
–
ns
R/W hold time from inactive data strobe
Thrw
0
–
–
ns
Chip select setup time to active data strobe
Tscs
0
–
–
ns
Chip select hold time from inactive data strobe
Thcs
0
–
–
ns
Address strobe active to data strobe active delay
Tasds
20
–
–
ns
Delay time from active data strobe to valid data
Tpds
3
–
30
ns
Delay time from inactive data strobe to data High Z
Tdz
3
–
30
ns
Valid data strobe pulse width
Tvds
60
–
–
ns
Inactive data strobe to inactive INT delay time
Tint
–
–
10
ns
Data strobe inactive to address strobe inactive delay
Tdsas
15
–
–
ns
DS asserted to ACK asserted delay
Tdackp
–
–
40
ns
DS deasserted to ACK deasserted delay
Tdack
–
–
10
ns
Active ACK to valid data delay
Tpack
–
–
0
ns
Test Conditions
1. Typical figures are at 25 C and are for design aid only; not guaranteed and not subject to production
testing.
2. CL= 100pF on D0-D7, all other outputs are loaded with 50pF.
Datasheet
67
LXT384 — Octal T1/E1/J1 Transceiver
Figure 25. Non-Multiplexed Motorola Mode Read Timing
A4-A0
ADDRESS
tSAR
AS
tHAR
(pulled High)
tSRW
tHRW
R/W
tSCS
tHCS
CS
tVDS
DS
tPDS
tDZ
D7-D0
DATA OUT
tINT
INT
tDACKP
tPACK
tDACK
ACK
Figure 26. Multiplexed Motorola Mode Read Timing
tVAS
tDSAS
AS
tSRW
tHRW
R/W
tSCS
tHCS
CS
tASDS
tVDS
DS
tSAR
D7-D0
tPDS
tHAR
tDZ
DATA OUT
ADDRESS
tINT
INT
tDACKP
tPACK
tDACK
ACK
68
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Table 50. Motorola Mode Write Timing Characteristics2
Parameter
Sym
Min.
Typ1
Max
Unit
Address setup time to address strobe
Tsas
10
–
–
ns
Address hold time to address strobe
Thas
5
–
–
ns
Valid address strobe pulse width
Tvas
95
–
–
ns
R/W setup time to active data strobe
Tsrw
10
–
–
ns
R/W hold time from inactive data strobe
Thrw
0
–
–
ns
Chip select setup time to active data strobe
Tscs
0
–
–
ns
Chip select hold time from inactive data strobe
Thcs
0
–
–
ns
Address strobe active to data strobe active delay
Tasds
20
–
–
ns
Data setup time to DS deassertion
Tsdw
40
–
–
ns
Data hold time from DS deassertion
Thdw
30
–
–
ns
Valid data strobe pulse width
Tvds
60
–
–
ns
Inactive data strobe to inactive INT delay time
Tint
–
–
10
ns
Data strobe inactive to address strobe inactive delay
Tdsas
15
–
–
ns
Active data strobe to ACK output enable time
Tdack
0
–
12
ns
DS asserted to ACK asserted delay
Tdackp
–
40
ns
Test Conditions
1. Typical figures are at 25 C and are for design aid only; not guaranteed and not subject to production
testing.
2. CL= 100pF on D0-D7, all other outputs are loaded with 50pF.
Figure 27. Non-Multiplexed Motorola Mode Write Timing
A4-A0
ADDRESS
tSAS
tHAS
AS (pulled High)
tSRW
tHRW
R/W
tSCS
tHCS
CS
tVDS
DS
tSDW
tHDW
WRITE DATA
D7-D0
tINT
INT
tDACKP
tDACK
ACK
Datasheet
69
LXT384 — Octal T1/E1/J1 Transceiver
Figure 28. Multiplexed Motorola Mode Write Timing
tVAS
tDSAS
AS
tHRW
tSRW
R/W
tHCS
tSCS
CS
tASDS
tVDS
DS
tSAS
D7-D0
tHDW
tHAS
tSDW
ADDRESS
WRITE DATA
tINT
INT
tDACKP
tDACK
ACK
Table 51. Serial I/O Timing Characteristics
Sym
Min.
Typ1
Max
Unit
Test Condition
Rise/fall time any pin
Trf
-
-
100
ns
Load 1.6mA, 50 pF
SDI to SCLK setup time
Tdc
5
-
-
ns
SCLK to SDI hold time
Tcdh
5
-
-
ns
Parameter
SCLK Low time
Tcl
25
-
-
ns
SCLK High time
Tch
25
-
-
ns
Tr, Tf
-
-
50
ns
Tcc
10
-
-
ns
SCLK rise and fall time
CS falling edge to SCLK rising edge
Last SCLK edge to CS rising edge
Tcch
10
-
-
ns
CS inactive time
Tcwh
50
-
-
ns
SCLK to SDO valid delay time
Tcdv
-
-
5
ns
SCLK falling edge or CS rising edge to SDO High Z
Tcdz
-
10
-
ns
1. Typical figures are at 25 C and are for design aid only; not guaranteed and not subject to production
testing.
70
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Figure 29. Serial Input Timing
CS
tCWH
tCC
tCH
tCCH
tCL
SCLK
tCDH
tDC
tCDH
LSB
LSB
SDI
MSB
CONTROL BYTE
DATA BYTE
Figure 30. Serial Output Timing
CLKE = 0
1
2
3
4
5
6
7
8
9
10
11
1
2
12
13
14
15
5
6
16
SCLK
CS
tCCH
tCDZ
SDO
0
4
3
7
CLKE = 1
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
SCLK
CS
0
SDO
1
2
3
4
5
tCDZ
6
tCCH
7
Table 52. Transformer Specifications
Tx/Rx
Turns Ratio2
Primary
Inductance
mH
(min.)
Leakage
Inductance
µH
(max.)
Interwinding
Capacitance
pF
(max.)
TX
1:2
1.2
0.60
60
RX
1:2
1.2
0.60
60
DCR
Ω
(max.)
0.70 pri
1.20 sec
1.10 pri
1.10 sec
Dielectric Breakdown
Voltage
V1
(min.)
1500 Vrms
1500 Vrms
1. This parameter is application dependent.
2. LIU side: Line side. Transformer turns ratio accuracy is ± 2%.
Datasheet
71
LXT384 — Octal T1/E1/J1 Transceiver
Table 53. G.703 2.048 Mbit/s Pulse Mask Specifications
Cable
Parameter
Unit
TWP
Coax
Test load impedance
120
75
Ω
Nominal peak mark voltage
3.0
2.37
V
Nominal peak space voltage
0 ±0.30
0
±0.237
V
244
244
ns
Ratio of positive and negative pulse amplitudes at center of pulse
95-105
95-105
%
Ratio of positive and negative pulse amplitudes at nominal half amplitude
95-105
95-105
%
Nominal pulse width
Figure 31. E1, G.703 Mask Templates
20%
194 ns
(244- 50)
20%
V = 100%
10% 10%
269 ns
(244+25)
NOMINAL PULSE
50%
244 ns
20%
10% 10%
0%
10% 10%
219 ns
(244-25)
488 ns
(244+244)
Table 54. T1.102 1.544 Mbit/s Pulse Mask Specifications
Cable
Parameter
Unit
TWP
Test load impedance
100
Ω
Nominal peak mark voltage
3.0
V
Nominal peak space voltage
0 ±0.15
V
324
ns
95-105
%
Nominal pulse width
Ratio of positive and negative pulse amplitudes
72
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Figure 32. T1, T1.102 Mask Templates
1.20
1.00
0.80
Normalized Amplitude
0.60
0.40
0.20
-0.80
-0.60
-0.40
-0.20
0.00
0.00
0.20
0.40
0.60
0.80
1.00
1.20
-0.20
-0.40
-0.60
Tim e [UI]
Datasheet
73
LXT384 — Octal T1/E1/J1 Transceiver
Figure 33. LXT384 Jitter Tolerance Performance
1000 UI
Jitter
100 UI
28 UI
@ 4.9 Hz
AT&T 62411, Dec 1990 (T1)
18 UI @ 1.8 Hz
LXT384 typ.
28 UI
@ 300 Hz
10 UI
GR-499-CORE, Dec 1995
(T1)
5 UI @ 500 Hz
1 UI
1.5 UI
@ 2.4 kHz
1.5 UI
@ 20 Hz
.1 UI
1 Hz
0.4 UI
@ 10 kHz
ITU G.823, Mar 1993
(E1)
0.2 UI
@ 18 kHz
0.1 UI @ 8 kHz
10 Hz
100 Hz
1 kHz
10 kHz
100 kHz
Frequency
74
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Figure 34. LXT384 Jitter Transfer Performance
E1
10 dB
ITU G.736 Template
0.5 dB @ 3Hz
0.5 dB @ 40Hz
0 dB
-10 dB
Gain
f
3dB=2.5
Hz
-19.5 dB @ 20 kHz
-20 dB
f
3dB=3.5
Hz
-19.5 dB @ 400 Hz
-30 dB
-40 dB
LXT384 typ.
-60 dB
-80 dB
1 Hz
10 Hz
100 Hz
1 kHz
10 kHz
100 kHz
Frequency
T1
10 dB
0 dB @ 1 Hz
0 dB @ 20 Hz 0.1 dB @ 40 Hz
0 dB
0.5 dB @ 350 Hz
AT&T Pub 62411
GR-253-CORE
TR-TSY-000009
Gain
-10 dB
-6 dB @
2 Hz
-20 dB
-33.3 dB @ 1 kHz
f
-30 dB
3dB=
f
-33.7 dB @ 2.5kHz
3 Hz
3dB=
-40 dB @ 1.4 kHz
6 Hz
-40 dB
-40 dB @ 70 kHz
-49.2 dB @ 15kHz
LXT384 typ.
-60 dB
-60 dB @ 57 Hz
-80 dB
1 Hz
10 Hz
100 Hz
1 kHz
10 kHz
100 kHz
Frequency
Datasheet
75
LXT384 — Octal T1/E1/J1 Transceiver
Figure 35. LXT384 Output Jitter for CTR12/13 Applications
Jitter Amplitude
(Ulpp)
0.2
0.15
0.1
LXT384 typ, f 3dB = 2.5Hz & 3.5 Hz
0.05
0
10 Hz
5.1
20 Hz
100 Hz
1 kHz
Frequency
10 kHz
100 kHz
Recommendations and Specifications
• AT&T Pub 62411
• ANSI T1.102 - 199X Digital Hierarchy Electrical Interface
• ANSI T1.231 -1993 Digital Hierarchy Layer 1 In-Service Digital Transmission Performance
Monitoring
76
•
•
•
•
•
•
•
•
Bellcore TR-TSY-000009 Asynchronous Digital Multiplexes Requirements and Objectives
•
•
•
•
G.736 Characteristics of a synchronous digital multiplex equipment operating at 2048 kbit/s
Bellcore GR-253-CORE SONET Transport Systems Common Generic Criteria
Bellcore GR-499-CORE Transport Systems Generic Requirements
ETS 300166 Physical and Electrical Characteristics
ETS 300386-1 Electromagnetic Compatibility Requirement
G.703 Physical/electrical characteristics of hierarchical digital interfaces
G. 704 Functional characteristics of interfaces associated with network nodes
G.735 Characteristics of Primary PCM multiplex equipment operating at 2048 kbit/s and
offering digital access at 384 kbit/s and/or synchronous digital access at 64 kbit/s
G.772 Protected Monitoring Points provided on Digital Transmission Systems
G.775 Loss Of Signal (LOS) and alarm indication (AIS) defect detection and clearance criteria
G.783 Characteristics of Synchronous Digital Hierarchy (SDH) Equipment Functional Blocks
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
• G.823 The control of jitter and wander within digital networks which are based on the 2048
kbit/s hierarchy
• O.151 Specification of instruments to measure error performance in digital systems
• OFTEL OTR-001 Short Circuit Current Requirements
Datasheet
77
LXT384 — Octal T1/E1/J1 Transceiver
6.0
Mechanical Specifications
Figure 36. Low Quad Flat Packages (LQFP) Dimensions
144 Pin LQFP
• Part Number LXT384LE
• Extended Temperature Range (-40°C to 85° C)
D
NOTE: All dimensions in millimeters.
D/2
b
e
E/2
E1/2
e/2
E1
E
M
0 DEG. MIN.
A2
0.08 / 0.20 R.
D1/2
A1
D1
0.08 R. MIN.
0.25
A
L
1.00
REF.
0 - 7 DEG.
Millimeters
Dimension1
Minimum
Nominal
Maximum
A
-
-
1.60
A1
0.05
0.10
0.15
A2
1.35
1.40
1.45
b
0.17
0.22
0.27
D
22.00 B.S.C.
D1
20.00 B.S.C.
E
22.00 B.S.C.
E1
20.00 B.S.C.
e
0.50 B.S.C.
L
0.45
0.60
0.75
M
0.14
-
-
1. See JEDEC Publication for additional specifications.
78
Datasheet
Octal T1/E1/J1 Transceiver — LXT384
Figure 37. Plastic Ball Grid Array (PBGA) Package Dimensions
160 Pin PBGA
• Part Number LXT384BE
• Extended Temperature Range (-40°C to 85° C)
15.00
13.00 ±0.20
1.00 REF
13.00
4.72 ±0.10
PIN #A1
CORNER
1.00
A
0.50 B
±0.10 C
PIN #A1 ID
D
4.72 ±0.10
1.00
E
F
13.00
15.00
±0.20
G
13.0
H
J
K
L
M
N
P
Ø1.00
(3 plcs)
14 13 12 11 10 9
TOP VIEW
8
7 6
5 4
3
2 1
1.00 R
BOTTOM VIEW
0.85
1.81
± 0.19
NOTE:
1. ALL DIMENSIONS IN MILLIMETERS.
SEATING PLANE
SIDE VIEW
Datasheet
0.56
±0.04
0.40
± 0.10
2. ALL DIMENSIONS AND TOLERANCES
CONFORM TO ASME Y 14.5M-1994.
3. TOLERANCE = ± 0.05 UNLESS
SPECIFIED OTHERWISE.
79