ETC XRT82L34IV

áç
XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
JUNE 2001
REV. 1.1.0
GENERAL DESCRIPTION
The XRT82L34 is a fully integrated Quad (four channels) short-haul line interface unit for T1(1.544Mbps)
100Ω and E1(2.048Mbps) 75Ω or 120Ω applications.
Each channel consists of a receiver with equalizer for
reliable data and clock recovery, and a transmitter
which accepts either single or dual-rail digital inputs
for signal transmission to the line using a low output
impedance line driver. The device also includes a
crystal-less jitter attenuator which, depending on system requirements, can be selected in the receive or
transmit path through the Host or Hardware Mode
control.
XRT82L34 is a low power CMOS device operating on
a single 3.3V supply with 5V tolerant digital inputs.
FEATURES
• Fully integrated quad, short-haul PCM transceivers
for E1 and T1 applications.
• On Chip Receive Equalizer and Transmit Pulse
Shaper for DS1 Digital Cross Connect (DSX-1) and
CEPT 75Ω and 120Ω line terminations
• Crystal-less jitter attenuator can be selected in the
transmit or receive path
• High receiver interference immunity
• Per-channel transmit power shutdown
• Tri-state transmit output capability
• On chip per-channel driver failure monitoring circuit
• On chip HDB3/B8ZS/AMI encoder/decoder functions
• Transmit return loss meets or exceeds ETSI 300
166 standard
• Meets or exceeds specifications in ITU G.703,
G.775, G.736 and G.823; Bellcore GR-499-CORE;
ANSI T1.403 and ETSI 300-166
• 3.3V or 5.0V Logic level inputs
• Single +3.3V Supply Operation
APPLICATIONS
• Digital cross connects (DSX-1)
• Channel Banks
• High speed data transmission line cards
• On chip clock recovery circuit
• T1/E1 Multiplexer
• Transformer or capacitor coupled receiver inputs
• Public switching systems and PBX interfaces
FIGURE 1. BLOCK DIAGRAM OF THE XRT82L34 T1/E1/J1 LIU (HOST MODE)
Driver
Monitor
TxClk[n]
TxPOS[n]/TDATA[n]
TxNEG[n]
HDB3/
B8ZS
Encoder
Enable/
Disable
RxClk[n]
RxPOS[n]/RDATA[n]
RxNEG[n]/LCV[n]
MUX
Tx/Rx Jitter
Attenuator
Tx Timing
Control
Tx Pulse
Shaper
Remote
LoopBack
Digital
LoopBack
HDB3/
B8ZS
Decoder
MUX
Tx/Rx Jitter
Attenuator
Timing & Data
Recovery
TTIP[n]
TRing[n]
Line
Driver
Local
Analog
LoopBack
Clock
Generator
TVDD[n]
TGND[n]
MClk
Peak
Detector
& Slicer
Rx
Equalizer
RTIP[n]
RRing[n]
LOS
Detect
RxLOS[n]
Channel 0
Channel 1
Channel 2
Channel 3
INT
RDY_DTACK
PClk/Codes
PTS1/ClkE
PTS2/SR_DR
Reset
ICT
µP Controller & Hardware Interface
Test
ADD [0:3]
D[0:7]
WR_R/W/TxOFF0
ALE_AS/TxOFF2
CS/TxOFF3
RD_DS/TxOFF1
HW/HOST
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (510) 668-7000 • FAX (510) 668-7017 • www.exar.com
áç
XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
FIGURE 2. BLOCK DIAGRAM OF THE XRT82L34 T1/E1/J LIU (HARDWARE MODE)
Driver
Monitor
One of four channels
TxClk[n]
TxPOS [n]/TDATA[n]
TxNEG[n]
HDB3/
B8ZS
Encoder
Enable/
Disable
RxClk[n]
RxPOS[n]/RDATA[n]
RxNEG[n]/LCV[n]
Tx/Rx Jitter
Attenuator
Tx Timing
Control
Tx Pulse
Shaper
Remote
LoopBack
Digital
LoopBack
HDB3/
B8ZS
Decoder
Tx/Rx Jitter
Attenuator
Timing & Data
Recovery
TTIP[n]
TRing[n]
Local
Analog
LoopBack
Clock
Generator
MUX
Line
Driver
TGND[n]
MClk
Peak
Detector
& Slicer
Rx
Equalizer
RTIP[n]
RRing[n]
LOS
Detect
RxLOS[n]
INT
RDY_DTACK
PClk/Codes
PTS1/ClkE
PTS2/SR/DR
Reset
WR_R/W/TxOFF0
ALE_AS/TxOFF2
CS/TxOFF3
RD_DS/TxOFF1
HW/HOST
ICT
MUX
TVDD[n]
µP Controler & Hardware Interface
Test
2
ADD[0]/ECC
ADD[1]/ECD
ADD[2]/ECA
ADD[3]/RxMute
D[0]/FIFOS
D[1]/LOOPEN0
D[2]/LOOPEN1
D[3]/LOOPEN2
D[4]LOOPEN3
D[5]/LOOPSEL
D[6]/RxJA
D[7]TxJA
áç
XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
ORDERING INFORMATION
PART NUMBER
PACKAGE
OPERATING TEMPERATURE RANGE
XRT82L34IV
100 Lead TQFP (14 x 14 x 1.4mm)
-40°C to +85°C
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
RxPOS_0/RData_0
RxNEG_0/LCV_0
DVDD
DGND
AGND
RRing_0
RTIP_0
AVDD
TGND_0
TRing_0
TVDD_0
TTIP_0
AVDD
TTIP_3
TVDD_3
TRing_3
TGND_3
AVDD
RTIP_3
RRing_3
AGND
DGND
DVDD
RxNEG_3/LCV_3
RxPOS_3/RData_3
FIGURE 3. PIN OUT OF THE XRT82L34
XRT82L34
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
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
RxPOS_1/RData_1
RxNEG_1/LCV_1
DVDD
DGND
DGND
RRing_1
RTIP_1
DVDD
TGND_1
TRing_1
TVDD_1
TTIP_1
AGND
TTIP_2
TVDD_2
TRing_2
TGND_2
AVDD
RTIP_2
RRing_2
AGND
DGND(PLL)
DVDD(PLL)
RxNEG_2/LCV_2
RxPOS_2/RData_2
RxClk_0
RxLOS_0
TxNEG_0
TxPOS_0/TData_0
TxClk_0
Reset
PTS1/ClkE
PTS2/SR/DR
HW/HOST
PClk/Codes
DGND
DVDD
DGND
WR_R/W/TxOFF_0
RD_DS/TxOFF_1
ALE_AS/TxOFF_2
CS/TxOFF_3
RDY_DTACK
INT
ICT
TxClk_1
TxPOS_1/TData_1
TxNEG_1
RxLOS_1
RxClk_1
3
75
74
73
72
71
70
69
68
67
66
65
64
63
62
61
60
59
58
57
56
55
54
53
52
51
RxClk_3
RxLOS_3
TxNEG_3
TxPOS_3/TData_3
TxClk_3
A[0]/ECC
A[1]/ECB
A[2]/ECA
A[3]/RxMute
MClk
DGND
DVDD
D[0]/FIFOS
D[1]/LOOPEN_0
D[2]/LOOPEN_1
D[3]/LOOPEN_2
D[4]/LOOPEN_3
D[5]/LOOPSEL
D[6]/RxJA
D[7]/TxJA
TxClk_2
TxPOS_2/TData_2
TxNEG_2
RxLOS_2
RxClk_2
áç
XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE OF CONTENTS
GENERAL DESCRIPTION ................................................................................................. 1
FEATURES ....................................................................................................................................................
APPLICATIONS ..............................................................................................................................................
Figure 1. Block Diagram of the XRT82L34 T1/E1/J1 LIU (Host Mode) .................................................
Figure 2. Block Diagram of the XRT82L34 T1/E1/J LIU (Hardware Mode) ...........................................
Figure 3. Pin Out of the XRT82L34 ..........................................................................................................
1
1
1
2
3
TABLE OF CONTENTS ....................................................................................................... I
PIN DESCRIPTIONS - BY FUNCTION ............................................................................... 4
MICROPROCESSOR PINS ............................................................................................................................... 4
RECEIVER .................................................................................................................................................... 6
TRANSMITTER ............................................................................................................................................... 7
CONTROL, ALARM, AND OTHER ..................................................................................................................... 8
JITTER ATTENUATOR .................................................................................................................................. 10
POWER AND GROUND ................................................................................................................................. 11
SYSTEM-FUNCTIONAL DESCRIPTION ......................................................................... 12
RECEIVER .................................................................................................................................................. 12
JITTER ATTENUATOR .................................................................................................................................. 12
HDB3/B8ZS DECODER .............................................................................................................................. 12
RECEIVER LOSS OF SIGNAL (LOS) .............................................................................................................. 12
CLOCK SIGNALS GENERATED WHEN LOS IS DECLARED ................................................................................ 12
DECLARING AND CLEARING LOS IN THE DS1 MODE. ................................................................................... 13
CONDITIONS FOR DECLARING AND CLEARING LOS IN THE E1 MODE. ............................................................ 13
RECEIVE DATA MUTING .............................................................................................................................. 13
LOOP-BACK MODES .............................................................................................................................. 13
REMOTE LOOP-BACK (RLOOP) MODE ...................................................................................................... 13
DIGITAL LOCAL LOOP-BACK (DLOOP) MODE ............................................................................................... 14
ANALOG LOCAL LOOP-BACK (ALOOP) MODE .............................................................................................. 14
Figure 4. Remote Loop-Back with jitter attenuator selected in receive path .................................... 14
Figure 5. Remote Loop-Back with jitter attenuator selected in transmit path .................................. 14
Figure 6. Digital Local Loop-Back with option to transmit all “ones” to the line (JA selected & in receive path) .............................................................................................................................. 15
Figure 7. Digital Local Loop-Back with option to transmit all “ones” to the line (JA selected & in
transmit path) ......................................................................................................................... 15
Figure 8. Analog Local Loop-Back signal flow Jitter Attenuator selected & in Receive path ........ 16
Figure 9. Analog Local Loop-Back signal flow Jitter Attenuator selected & in transmit path ........ 16
RESET OPERATION ..................................................................................................................................... 16
RECEIVER MODES OF OPERATION ............................................................................................................... 16
RECEIVE DATA INVERT MODE ..................................................................................................................... 16
Figure 10. Data changes on rising edge of Clk and Data is sampled on falling edge ..................... 17
Figure 11. Data changes on falling edge of Clk and is sampled on rising edge .............................. 17
TRANSMIT CLOCK SAMPLING EDGE ............................................................................................................. 17
SINGLE RAIL, DUAL RAIL .............................................................................................................................. 17
TRANSMIT ALL ONES (TAOS) ..................................................................................................................... 17
HDB3/B8ZS/AMI ENCODER ....................................................................................................................... 17
TRANSMIT PULSE SHAPER .......................................................................................................................... 18
DRIVER MONITOR ....................................................................................................................................... 18
TRANSMIT OFF CONTROL ............................................................................................................................ 18
TABLE 1: EXAMPLES OF B8ZS ENCODING .................................................................................................. 18
TABLE 2: TRANSMIT EQUALIZER CONTROL ................................................................................................. 18
INTERFACING THE XRT82L34 TO THE LINE ................................................................................................. 18
Figure 12. XRT82L34 Channel_0 in an E1 unbalanced 75 W application - 1:2 or (1:2.45) transformer
19
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
Figure 13. XRT82L34 Channel_0 - E1 120 W balanced application - 1:2 or (1:2.45) transformer ...
Figure 14. XRT82L34 Channel_0 - DS1 100 W Balanced application ................................................
TABLE 3: E1 RECEIVER ELECTRICAL CHARACTERISTICS .............................................................................
TABLE 4: T1 RECEIVER ELECTRICAL CHARACTERISTICS .............................................................................
TABLE 5: E1 TRANSMITTER ELECTRICAL CHARACTERISTICS .......................................................................
TABLE 6: T1 TRANSMITTER ELECTRICAL CHARACTERISTICS .......................................................................
TABLE 7: TRANSMIT PULSE MASK SPECIFICATION ......................................................................................
Figure 15. ITU G.703 E1 Pulse Template ..............................................................................................
TABLE 8: DS1 INTERFACE ISOLATED PULSE MASK AND CORNER POINTS. ....................................................
Figure 16. DSX-1 Pulse Template .........................................................................................................
TABLE 9: DC ELECTRICAL CHARACTERISTICS ............................................................................................
TABLE 10: POWER DISSIPATION (XRT82L34 ONLY) ...................................................................................
TABLE 11: POWER CONSUMPTION (XRT82L34 AND LOAD: PD=VDD X IDD) ...............................................
19
20
21
22
23
23
24
24
25
25
26
26
26
ABSOLUTE MAXIMUM RATINGS ................................................................................... 27
TABLE 12: AC ELECTRICAL CHARACTERISTICS .......................................................................................... 27
Figure 17. Transmit Clock and Input Data Timing .............................................................................. 28
Figure 18. Receive Clock and Output Data Timing. ............................................................................ 28
TABLE 13: MICROPROCESSOR INTERFACE SIGNAL ...................................................................................... 29
TABLE 14: MICROPROCESSOR REGISTER MAP ........................................................................................... 30
TABLE 15: COMMAND CONTROL REGISTER 0 ............................................................................................. 31
TABLE 16: COMMAND CONTROL REGISTER 1 ............................................................................................. 32
TABLE 17: CHANNEL STATUS REGISTER .................................................................................................... 33
TABLE 18: CHANNEL MASK REGISTER ....................................................................................................... 34
TABLE 19: CHANNEL CONTROL REGISTER ................................................................................................ 35
Figure 19. Intel Interface Timing (Read) ............................................................................................... 36
Figure 20. Intel Interface Timing (Write) ............................................................................................... 36
TABLE 20: INTEL INTERFACE TIMING SPECIFICATIONS ................................................................................. 37
Figure 21. Microprocessor Interface Timing - Motorola Type Programmed I/O Read Operation ... 38
Figure 22. Microprocessor Interface Timing - Motorola Type Programmed I/O Write Operation ... 38
Figure 23. Microprocessor Interface Timing - Reset Pulse Width ..................................................... 38
TABLE 21: MOTOROLA INTERFACE TIMING SPECIFICATION .......................................................................... 39
JITTER TOLERANCE IN DS1 APPLICATIONS .................................................................................................. 40
Figure 24. Input Jitter Tolerance performance of the XRT82L34, for DS1 Applications, with the Jitter
Attenuator Disabled .............................................................................................................. 40
JITTER ATTENUATOR ENABLED AND CONFIGURED TO OPERATE IN THE RECEIVE PATH ................................. 41
Figure 25. Input Jitter Tolerance Capability of the XRT82L34 for DS1 Applications with the Jitter Attenuator Enabled and operating in the Receive Path ........................................................ 41
JITTER TRANSFER CHARACTERISTICS OF THE XRT82L34 CONFIGURED TO OPERATE IN THE DS1 MODE ...... 42
Figure 26. Jitter Transfer Characteristics of the XRT82L34 for DS1 Applications with the Jitter Attenuator Enabled and Operating in the Receive Path ............................................................. 42
APPENDIX A ..................................................................................................................... 43
XRT82LL34 AND XRT82L24 EVALUATION KIT (XRT82L34/L24EVAL) ...................................................... 43
Figure 27. XRT82L34/L24 GUI Software Interface for Evaluating the XRT82L24/L34EVAL Application
Board ...................................................................................................................................... 43
Figure 28. Photograph of the XRT82L34/L24EVAL Application Board ............................................. 44
Figure 29. Block Layout of the XRT82L34/L24EVAL Application Board ........................................... 45
ORDERING INFORMATION ............................................................................................................................ 46
PACKAGE DIMENSIONS 100 LEAD TQFP 14X14MM ..................................................................................... 46
REVISION HISTORY ..................................................................................................................................... 47
II
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
PIN DESCRIPTIONS - BY FUNCTION
MICROPROCESSOR PINS
PIN #
NAME
TYPE
7
PTS1
I
DESCRIPTION
Processor Type Select bit 1:
Host Mode
In Host Mode the appropriate bits are set in the command mode
PTS1
PTS2
0
0
8HC11,8081,80C188 (async.)
1
0
Motorola 68K (async.)
0
1
Intel x86 (sync.)
1
1
Intel i906,Motorola 860 (sync.)
8
PTS2
I
Host Mode:
Processor Type Select Input bit 2:
See description for pin 7.
10
PCLK
I
Processor Clock Input.
Input clock for synchronous microprocessor operation. Maximum clock rate is
16 MHz. This pin is internally pull-up for asynchronous microprocessor interface
when no clock is present.
14
WR_R/W
I
Write Input (Read/Write).
With Intel bus timing, a Low pulse on WR selects a write operation when CS pin
is Low. When configured in Motorola bus timing, a "High" pulse on R/W selects
a read operation and a Low pulse on R/W selects a write operation when CS is
Low.
15
RD_DS
I
Read Input (Data Strobe).
With Intel bus timing, a Low pulse on RD selects a read operation when CS pin
is Low. When configured in Motorola bus timing, a Low pulse on DS indicates a
read or write operation when CS pin is Low.
16
ALE_AS
I
Address Latch Input (Address Strobe).
With Intel bus timing, the address inputs are latched into the internal register on
the falling edge of ALE. When configured in Motorola bus timing, the address
inputs are latched into the internal register on the falling edge of AS.
17
CS
I
Chip Select Input.
This signal must be Low in order to access the parallel port.
18
RDY_DTACK
O
Ready Output (Data Transfer Acknowledge Output).
With Intel bus timing, RDY is asserted "High" to indicate the device has completed a read or write operation. When configured in Motorola bus timing,
DTACK is asserted Low to indicate the device has completed a read or write
cycle.
NOTE: Internally pulled -up with a 50kΩ resistor.
4
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
MICROPROCESSOR PINS
PIN #
NAME
TYPE
63
62
61
60
59
58
57
56
D[0]
D[1]
D[2]
D[3]
D[4]
D[5]
D[6]
D[7]
I/O
70
69
68
67
A[0]
A[1]
A[2]
A[3]
I
DESCRIPTION
Data Bus[7:0].
Microprocessor read/write data bus
Host Mode, Microprocessor Interface Address Bus [3:0].
5
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
RECEIVER
PIN #
NAME
TYPE
1
25
51
75
RxCLK_0
RxCLK_1
RxCLK_2
RxCLK_3
O
Receiver_n Clock Output
2
24
52
74
RxLOS_0
RxLOS_1
RxLOS_2
RxLOS_3
O
Receiver_n Loss of Signal. This signal is asserted "High" to indicate
loss of signal at the receive input.
100
RxPOS_0
O
Receiver_n Positive Data Output:
In dual-rail mode, p-rail data are sent to the framer.
Receiver 0 NRZ Data Output:
In single-rail mode, the received data are sent in NRZ format to the
framer.
O
Receiver_n Negative Data Output:
In dual-rail mode, n-rail data are sent to the framer.
Line Code Violation Output:
In single-rail mode, this signal output "High" for one receive clock cycle to
indicate a code violation is detected in the received data. If AMI coding is
selected, every bipolar violation received will cause this pin to go "High".
/RData_0
26
50
76
RxPOS_1/RData_1
RxPOS_2/RData_2
RxPOS_3/RData_3
99
RxNEG_0
/LCV_0
DESCRIPTION
27
49
77
RxNEG_1/LCV_1
RxNEG_2/LCV_2
RxNEG_3/LCV_0
94
32
44
82
RTIP_0
RTIP_1
RTIP_2
RTIP_3
I
Receiver_n Differential Positive Input.
95
31
45
81
RRing_0
RRing_1
RRing_2
RRing_3
I
Receiver_n Differential Negative Input.
6
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TRANSMITTER
PIN #
NAME
TYPE
DESCRIPTION
3
23
53
73
TxNEG_0
TxNEG_1
TxNEG_2
TxNEG_3
I
Transmitter_n Negative NRZ Data Input. In dual-rail mode, this signal
is the n-rail input data for transmitter n. In single-rail mode, this pin can
be left unconnected.
NOTE: Internally pulled -up with a 50kΩ resistor.
4
TxPOS_0
I
Transmitter_n Positive Data Input. In dual-rail mode, this signal is the
p-rail input data for transmitter n.
Transmitter 0 Data Input. In single-rail mode, this pin is used as the
NRZ input data for transmitter 0.
NOTE: Internally pulled -up with a 50kΩ resistor.
TData_0
22
54
72
TxPOS_1/TData_1
TxPOS_2/TData_2
TxPOS_3/TData_3
5
21
55
71
TxClk_0
TxClk_1
TxClk_2
TxClk_3
I
Transmitter_n Clock Input.
E1 rate at 2.048MHz ± 50ppm. T1 rate at 1.544MHz ± 32ppm. During
normal operation both in Host Mode and Hardware Mode, TxClk is used
for sampling input data at TxPOS/TData and TxNEG, while MCLK is
used as the timing reference for the transmit pulse shaping circuit. In
Hardware Mode, if TxClk is tied "High" for more than 10 µs, then TAOS (a
continuous all one's AMI signal) will be transmitted to the line using
MCLK as timing reference.
If TxClk_n is tied “Low” for more than 10 µs, the transmitter will be powered down and the output will be tri-stated.
NOTES:
1. Internally pulled -up with a 50kΩ resistor.
2. See Figure 10 and Figure 11.
91
35
41
85
TRing_0
TRing_1
TRing_2
TRing_3
O
Transmitter_n Ring Output. Negative Differential data output to the
line.
89
37
39
87
TTIP_0
TTIP_1
TTIP_2
TTIP_3
O
Transmitter_n Tip Output. Positive Differential data output to the line.
7
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
CONTROL, ALARM, AND OTHER
PIN #
NAME
TYPE
DESCRIPTION
66
MCLK
I
Master Clock Input.
This signal is an independent 2.048MHz clock for E1 and 1.544Mhz
clock for T1 system with accuracy better than ±50ppm and duty cycle
within 40% to 60%. The function of MCLK is to provide internal timing for
the PLL clock recovery circuit, jitter attenuator block, reference clock during transmit all ones data and timing reference for the microprocessor in
Host Mode operation.
If MCLK is not present for more than 10 µs the transmitter will be powered down and the output will be tri-stated.
NOTE: Internally pulled -up with a 50kΩ resistor.
9
HW/HOST
I
Mode Control Input:
This pin is used to select the operating mode of the device, (Hardware
Mode or Host Mode.)
In Hardware Mode, the parallel Microprocessor interface is disabled and
enables all hardware control pin functions.
In Host Mode, the parallel microprocessor interface pins are used for
control functions.
Pin 9
Operating Mode
“Low”
Host Mode
“High”
Hardware Mode
NOTE: Internally pulled "High" with 50kΩ.
14
15
16
17
TxOff_0
TxOff_
TxOff_
TxOff_
I
Powered-down Transmitter_n.
Hardware Mode,
tie this pin "High" to power-down channel 0 transmitter and set TTIP_n
and TRing_n to high impedance.
NOTE: Internally pulled -up with a 50kΩ resistor.
10
Codes
I
Coding/Decoding Select. In Hardware Mode, if single-rail data format is
selected (pin 8 =”1”), connect this pin "High" to select AMI encoding and
decoding. Connect this pin Low to select HDB3 in E1 or B8ZS in T1 system.
6
RESET
I
Hardware Reset (Active Low). When this pin is tied Low for more than
10µS, the device is put in the reset state.
NOTE: Internally pulled -up with a 50kΩ resistor.
7
CLKE
I
Hardware Mode
Clock Edge:
In Hardware Mode, connect this pin Low to select falling edge of TxClk to
sample input data and also select RxPOS/RxNEG data to be valid on
falling edge of RxClk. Connect this pin "High" to select rising edge of
TxClk to sample input data and also selects RxPOS/RxNEG data to be
updated on the rising edge of RxClk.
8
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
CONTROL, ALARM, AND OTHER
PIN #
NAME
TYPE
DESCRIPTION
8
SR/DR
I
Hardware Mode
Single rail/Dual Rail Control
Connect this pin “Low” to select transmit and receive data format in dualrail mode. In this mode, HDB3 or B8ZS encoder and decoder are not
available. Connect this pin "High" to select single-rail data format.
NOTE: Internally pulled -up with a 50kΩ resistor.
19
INT
O
Interrupt Output.
This pin is asserted Low to indicate an alarm condition has occurred
within the device. Interrupt generation can be globally disabled by setting the GIE bit to a "0" in the command control register.
NOTE: This pin is an open drain output and requires an external 10KΩ
pull-up resistor.
20
ICT
I
In-Circuit Testing (Active Low).
When this pin is tied Low, all output pins are forced to high impedance
state for in-circuit testing.
NOTE: Internally pulled -up with 50kΩ.
58
LOOPSEL
I
Loop-back Mode Select.
Hardware Mode:
If LOOPEN_(0-3) is “High”, this pin is used for selecting loop-back mode.
Connect this pin "High" to select local loop-back .
Connect this pin “Low” to select remote loop-back.
Digital Loop-back is not supported in Hardware Mode.
NOTE: Internally pulled -up with a 50kΩ resistor.
62
61
60
59
LOOPEN_0
LOOPEN_1
LOOPEN_2
LOOPEN_3
I
Loop-back Enable: Channel_n
In Hardware Mode, connect this pin “High” to enable channel_n loopback operation. Remote or local loop-back is determined by pin 58 setting. Digital Loop-back is not supported in Hardware Mode.
NOTE: Internally pulled -up with a 50kΩ resistor.
67
RXMUTE
I
Hardware Mode, Receive Muting:
Connect this pin "High" to mute RxPOS/RxNEG output to a low state
upon receive LOS condition to prevent data chattering. Connect Low to
disable muting function.
NOTE: Internally pulled -up with a 50kΩ resistor.
68
ECA
I
Hardware Mode, Transmit Equalizer Control A
This pin together with ECB and ECC are used for controlling transmit
pulse shaping and also selects T1 or E1 Mode of operation.
See Table 2 Section 1.
NOTES:
1. All transmit channels in T1 mode share the same pulse setting in
Hardware Mode.
2. Internally pulled -up with a 50kΩ resistor.
69
ECB
I
Hardware Mode, Transmit Equalizer Control B
This pin together with ECA and ECC are used for controlling transmit
pulse shaping and also selects T1 or E1 Mode of operation.
NOTE: Internally pulled -up with a 50kΩ resistor.
9
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
CONTROL, ALARM, AND OTHER
PIN #
NAME
TYPE
70
ECC
I
DESCRIPTION
Hardware Mode, Transmit Equalizer Control C
This pin together with ECB and ECA are used for controlling transmit
pulse shaping and also selects T1 or E1 Mode of operation.
NOTE: Internally pulled -up with a 50kΩ resistor.
JITTER ATTENUATOR
PIN #
NAME
TYPE
DESCRIPTION
56
TXJA
I
Transmit Jitter Attenuator Select.
In Hardware Mode, connect this pin “High” to select jitter attenuator in
the transmit path and connect Low to disable jitter attenuator.
Setting RXJA simultaneously "High" also disables jitter attenuator selection.
NOTE: Internally pulled -up with a 50kΩ resistor.
57
RXJA
I
Receive Jitter Attenuator Select.
In Hardware Mode, connect this pin “High” to select jitter attenuator in
the receive path and connect Low to disable jitter attenuator.
Setting TXJA simultaneously "High" also disables jitter attenuator selection.
NOTE: Internally pulled -up with a 50kΩ resistor.
63
FIFOS
I
FIFO Size Select.
In Hardware Mode, connect this pin "High" selects 64 bit FIFO depth and
connect Low to select 32 bit FIFO depth.
NOTE: Internally pulled -up with a 50kΩ resistor.
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
POWER AND GROUND
PIN #
NAME
TYPE
DESCRIPTION
12
DVDD
****
Digital Positive Supply(3.3V± 5%)
28
DVDD
****
Digital Positive Supply(3.3V± 5%)
33
DVDD
****
Digital Positive Supply(3.3V± 5%)
64
DVDD
****
Digital Positive Supply(3.3V± 5%)
78
DVDD
****
Digital Positive Supply(3.3V± 5%)
98
DVDD
****
Digital Positive Supply(3.3V± 5%)
11
DGND
****
Digital Ground
13
DGND
****
Digital Ground
29
DGND
****
Digital Ground
30
DGND
****
Digital Ground
65
DGND
****
Digital Ground
79
DGND
****
Digital Ground
97
DGND
****
Digital Ground
90
36
40
86
TVDD_0
TVDD_1
TVDD_2
TVDD_3
****
Transmitter_n Analog Positive Supply(3.3V± 5%)
92
34
42
84
TGND_0
TGND_1
TGND_2
TGND_3
****
Transmitter_n Analog Ground.
48
DVDD(PLL)
****
Analog Positive Supply(3.3V± 5%), used for PLL
47
DGND(PLL)
****
Analog Ground (used for PLL)
43
AVDD
****
Analog Positive Supply(3.3V± 5%)
83
AVDD
****
Analog Positive Supply(3.3V± 5%)
88
AVDD
****
Analog Positive Supply(3.3V± 5%)
93
AVDD
****
Analog Positive Supply(3.3V± 5%)
38
AGND
****
Analog Ground
46
AGND
****
Analog Ground
80
AGND
****
Analog Ground
96
AGND
****
Analog Ground
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
SYSTEM-FUNCTIONAL DESCRIPTION
the narrow bandwidth requirement as specified in
ITU- G.736, ITU- I.431 and AT&T Pub 62411 standards.
A simplified single channel block diagram of the
XRT82L34 is presented in Figure 1. The XRT82L34
consists of four identical transmit and receive channels for E1(2.048 Mbps) and T1(1.544 Mbps) PCM
systems. The operational mode of each channel of
the line interface can be configured by the microprocessor interface (Host Mode) or by Hardware control.
HDB3/B8ZS DECODER
The decoder function is only active if the chip has
been configured to operate in the single-rail mode.
When the single-rail mode is selected, the receive
line signal will be decoded according to HDB3 rules
for E1 and B8ZS for T1. Further, any bipolar
violaHDB3 or B8ZS line coding scheme will be
flagged as a Line Code Violation via the LCV output
pin. The LCV output pin will be pulsed high for one
RxClk cycle for each line code violation that is detected. Excessive number of zeros in the receive data
stream are also flagged as a line code violation via
the same output pin. If AMI decoding is selected in
single-rail mode operation, every bipolar violation in
the receive data stream is reported as error at the
LCV pin.
RECEIVER
At the receiver input, cable attenuated AMI signals
can be coupled to the receiver using a capacitor or a
2:1 step-down transformer. The receive signal first
goes through the equalizer for signal conditioning before being applied to the data recovery circuit. The
data recovery circuit includes a peak detector which
is set typically at 50% for E1 (65% for T1) of the
equalizer output peak amplitude for data slicing. After
the data slicers, the digital representation of the AMI
signals goes to the clock recovery circuit for timing recovery and subsequently to the HDB3 or B8ZS decoder (if selected) before they are output via the RxPOS/RDATA and RxNEG/LCV pins. The digital data
output can be in dual-rail or single-rail mode depending on the option selected. Clock and timing recovery
is accomplished by means of a digital PLL scheme
which can tolerate high input jitter and meets or exceeds the jitter tolerance requirements as specified in
the ITU - G.823 and Bellcore GR-499-CORE standards.
RECEIVER LOSS OF SIGNAL (LOS)
The receiver loss of signal monitoring function is implemented using both analog and digital detection
schemes compatible with ITU G.775 requirements.
When the amplitude of the E1 or T1 line signal at
RTIP/RRING drops 20dB below the 0dB nominal level, the digital circuit is activated to parse through and
check for 32 consecutive zeros in E1 and 175 zeros in
T1 modes, before LOS is asserted to indicate loss of
input signal. The number of consecutive zeros before
LOS is declared can be increased to 4096 bits in both
E1 and T1 mode (when operating in the Host Mode).
The LOS condition is cleared when the input signal
rises above 20dB below 0dB nominal level and meets
12.5% density of 4 ones in a 32 bit window with no
more than 16 consecutive zeros for E1 and 16 ones
in a 128 bit window with no more than 100 consecutive zeros in the T1 data stream.
JITTER ATTENUATOR
To reduce jitter in the transmit line signal or recovered
clock and data signals, a crystal-less jitter attenuator
with a 32x2 bit or 64x2 bit FIFO is provided for each
channel. The jitter attenuator can be configured to operate in either the transmit or receive path, or it can
be disabled through Host or Hardware Mode control.
The jitter attenuator design is based on a digital
scheme that uses the MCLK signal as a reference input. No other high frequency clock is necessary. With
the jitter attenuator selected, the typical throughput
delay is 16 bits for a 32 bit FIFO depth or 32 bit for a
64 bit FIFO depth. The design of the jitter attenuator
is such that if the write and read pointers of the FIFO
are within two bits of overflowing or underflowing, the
bandwidth of the jitter attenuator is automatically widened in order to permit the “Jitter Attenuator” PLL to
track the short term input jitter to avoid data corruption. When this situation occurs, the jitter attenuator
will not attenuate input jitter until the read/write pointer's position is outside the two bit window. Under normal condition, the jitter transfer characteristic meets
CLOCK SIGNALS GENERATED WHEN LOS IS
DECLARED
The output signal at the RxClk output pin depends
upon the type of LOS condition that is occurring.
Complete Loss of Signal (Zero Amplitude)
If the XRT82L34 experiences a complete Loss of Signal (e.g., no signal amplitude), then the XRT82L34
Clock Recovery PLL enters the Training Mode, an Differentially begins to lock onto the signal applied to the
MCLK input pin. As a consequence, the Clock Recovery PLL will begin to drive a clock signal to the Terminal Equipment (via the RxClk output pin), which is derived from the MCLK input pin.
12
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
Degraded Type of Loss of Signal Event (Non-Zero
Amplitude)
LOS condition, if it determines that the amplitude of
the incoming line signal has dropped to less than
-15dB (below the nominal pulse amplitude of 3V for
twisted-pair, or 2.37V for coaxial-cable) for at least
32 bit-periods.
If the XRT82L34 experiences a degraded type of LOS
event (e.g., where there is still a small amount of discernible signal amplitude in the line signal, but small
enough to qualify as an LOS event) then the Clock
Recovery PLL could lock onto this degraded line signal and will subsequently drive the same frequency
via the RxClk output pins.
The Analog LOS Detector will clear the LOS condition, if it determines that the incoming line signal is no
more than 12.5dB below the nominal 3V pulse amplitude.
NOTE: The difference in the signal level required to declare
and clear LOS is 2.5dB. This 2.5dB hysteresis is designed
into the Analog LOS Detector circuitry, in order to prevent
chattering in the LOS output pin or bit-field.
DECLARING AND CLEARING LOS IN THE DS1
MODE.
Each channel of the XRT82L34 has two criteria for
LOS Detection, Analog and Digital. A channel will
declare an LOS condition when both of these LOS
Detectors detects an LOS condition.
Digital LOS Detector
If a given channel is configured to operate in the E1
Mode, then the Digital LOS Detector will declare an
LOS condition, if it detects a string of at least 32 consecutive "0"s.
Analog LOS Detector
If a given channel is configured to operate in the DS1
Mode, then the Analog LOS Detector will declare an
LOS condition, if it determines that the amplitude of
the incoming line signal has dropped -15dB (below
the nominal pulse amplitude of 3V) for at least 175
consecutive bit-periods.
The Digital LOS Detector will clear the LOS condition,
if it determines that the incoming E1 line signal has a
pulse density of 25% or more, for at least 32 consecutive bit periods.
NOTE: The pulse density requirement of 25% accounts for
HDB3 coding.
Conversely, the Analog LOS Detector will clear the
LOS condition, if it determines that the incoming line
signal is no more than 12.5dB below the nominal 3V
pulse amplitude.
RECEIVE DATA MUTING
The XRT82L34 permits the user to “MUTE” the recovered data output signals anytime the LOS condition is declared. If the user invokes this function, then
the RPOS/RDAT and RNEG output pins will be pulled
to GND for the duration that the LOS condition exists.
This feature is useful in that it prevents the LIU from
routing electrical noise (which has been “recovered”
by the Clock Recovery PLL) to the Framer IC and preventing it from declaring an LOS condition. This feature is enabled by setting the RXMUTE bit to a “1” in
the Host Mode or by connecting pin 67 High in the
Hardware Mode.
NOTE: The difference in the signal level required to declare
and clear LOS is 2.5dB. This 2.5dB hysteresis is designed
into the Analog LOS Detector circuitry, in order to prevent
chattering in the LOS output pin or bit-field.
Digital LOS Detector
If a given channel is configured to operate in the DS1
Mode, then the Digital LOS Detector will declare an
LOS condition, if it detects a string of at least 175
consecutive zeroes within the receive data stream.
The Digital LOS Detector will clear the LOS condition,
if it determines that the incoming DS1 line signal has
a pulse density of 12.5% or more.
LOOP-BACK MODES
Each channel within the XRT82L34 can be configured to operate in any of the following loop-back
modes:
NOTE: The pulse density requirement of 12.5% accounts
for B8ZS coding.
CONDITIONS FOR DECLARING AND CLEARING
LOS IN THE E1 MODE.
Similar to the DS1 mode, each E1 channel of the
XRT82L34 has two criteria for LOS Detection, Analog and Digital. A channel will declare an LOS condition when both of these LOS Detectors detect an
LOS condition.
• Remote Loop-Back Mode
• Digital Local Loop-Back Mode
• Analog Local Loop-Back Mode
Each of these loop-back modes are described in
some detail below.
REMOTE LOOP-BACK (RLOOP) MODE
With Remote Loop-Back activated, received data after the jitter attenuator (if selected) is looped back to
the transmit path using RxClk as transmit timing. In
Analog LOS Detector
If a given channel is configured to operate in the E1
Mode, then the Analog LOS Detector will declare an
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
ture allows users to configure the line interface as a
pure jitter attenuator. (see Loop-Back Mode in
Figure 6 & Figure 7).
this mode the data/signals applied to the TxClk,
TPOS/TDAT and TNEG input pins are ignored, while
RxClk and received data will continue to be available
at their respective output pins. Simultaneously setting
RLOOP and ALOOP active is not allowed (see LoopBack Mode in Figure 4 & Figure 5). Remote loopback has priority over TAOS.
NOTE: Digital Local Loop-Back is not supported in Hardware Mode.
ANALOG LOCAL LOOP-BACK (ALOOP) MODE
With Analog Local Loop-Back activated, the transmit
data at TTIP and TRING are looped-back to the analog input of the receiver. External inputs at RTIP/
RRING in this mode are ignored while valid transmit
data continues to be sent to the line. Analog LoopBack exercises most of the functional blocks of the
line interface (see Loop-Back Mode in Figure 8 &
Figure 9).
DIGITAL LOCAL LOOP-BACK (DLOOP) MODE
The Digital Local Loop-Back mode allows the transmit clock and data to be looped back to the corresponding receiver output pins through the encoder/
decoder and the jitter attenuator. In this mode, the receive line signal is ignored, but the transmit data will
be sent to the line uninterrupted. This loop back fea-
FIGURE 4. REMOTE LOOP-BACK WITH JITTER ATTENUATOR SELECTED IN RECEIVE PATH
TxPOS
TxNEG
Timing
Control
Encoder
TTIP
Tx
TRing
TxClk
RxClk
RxPOS
Decoder
RTIP
Clock &
Data
Recovery
JA
Rx
RRing
RxNEG
FIGURE 5. REMOTE LOOP-BACK WITH JITTER ATTENUATOR SELECTED IN TRANSMIT PATH
TxPOS
TxNEG
Encoder
Timing
Control
JA
TTIP
Tx
TRing
TxClk
RxClk
RxPOS
Clock &
Data
Recovery
Decoder
RxNEG
14
RTIP
Rx
RRing
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
“
FIGURE 6. DIGITAL LOCAL LOOP-BACK WITH OPTION TO TRANSMIT ALL “ONES” TO THE LINE (JA SELECTED & IN
RECEIVE PATH)
TAOS
TxPOS
TxNEG
Timing
Control
Encoder
TTIP
Tx
TRing
TxClk
RxClk
RxPOS
Decoder
RTIP
Clock &
Data
Recovery
JA
Rx
RRing
RxNEG
FIGURE 7. DIGITAL LOCAL LOOP-BACK WITH OPTION TO TRANSMIT ALL “ONES” TO THE LINE (JA SELECTED & IN
TRANSMIT PATH)
TxPOS
TxNEG
Encoder
Timing
Control
JA
TTIP
Tx
TRing
TxClk
TAOS
RxClk
RxPOS
Clock &
Data
Recovery
Decoder
RxNEG
15
RTIP
Rx
RRing
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
FIGURE 8. ANALOG LOCAL LOOP-BACK SIGNAL FLOW JITTER ATTENUATOR SELECTED & IN RECEIVE PATH
TxPOS
TxNEG
TTIP
Timing
Control
Encoder
Tx
TRing
TxClk
RxClk
RxPOS
Decoder
Clock &
Data
Recovery
JA
RTIP
Rx
RRing
RxNEG
FIGURE 9. ANALOG LOCAL LOOP-BACK SIGNAL FLOW JITTER ATTENUATOR SELECTED & IN TRANSMIT PATH
TxPOS
TxNEG
Encoder
TTIP
Timing
Control
JA
Tx
TRing
TxClk
RxClk
RxPOS
Decoder
Clock &
Data
Recovery
RTIP
Rx
RRing
RxNEG
RESET OPERATION
The XRT82L34 provides both Hardware and Software resets. In Hardware reset, with pin 6 forced to
"0" for more than 10µs, the entire state of the device
including the microprocessor R/W registers are reset.
In Software reset, only the state of the interface is reset (the microprocessor registers are not affected).
modes of operation making it flexible for different applications as dictated by the system requirements.
RECEIVE DATA INVERT MODE
Receive output data by default is active high at RxPOS/RDATA and RxNEG/LCV pins. These signals
can be changed to active Low by setting the DATAP
bit in the interface register. In single rail mode
(DataF=1), LCV output also becomes active Low. Data invert Mode is only available in Host Mode.
RECEIVER MODES OF OPERATION
Through the microprocessor interface or in Hardware
Mode, XRT82L34 offers several alternative receive
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QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
FIGURE 10. DATA CHANGES ON RISING EDGE OF CLK AND DATA IS SAMPLED ON FALLING EDGE
Clk
Data
Data Sampled
Data Sampled
FIGURE 11. DATA CHANGES ON FALLING EDGE OF CLK AND IS SAMPLED ON RISING EDGE
Clk
Data
Data Sampled
Data Sampled
TRANSMIT ALL ONES (TAOS)
In the Host Mode, individual channels can be programmed to transmit an all “Ones” AMI signal by setting the per channel bit control TAOS=1. In this mode,
input data at TxPOS/TDATA and TxNEG are ignored.
In Host Mode, reference clock for TAOS is TxClk. If
TxClk is not available, MCLK is used for transmission.
In Hardware Mode, if TxClk is not present and High
for more than 10µs, TAOS is transmitted using MCLK
as a reference. Remote Loop-Back has priority over
TAOS request.
RxClk Clock Sampling Edge
The sampling edge of the RxClk output can be
changed through control bit RClkE within the interface register for receive output data re-timing. With
RClkE=1, data is validated on the rising edge of RxClk and with RClkE=0, receive data is validated on
the falling edge of RxClk. In Hardware Mode, the
state of pin 7 (ClkE) controls the rising or falling edge
of RxClk for data re-timing.
TRANSMIT CLOCK SAMPLING EDGE
Transmit data at TxPOS/TDATA or TxNEG is clocked
serially into the device using TxClk. With the interface
register bit 4 (TClk=1), input data is sampled on the
rising edge of TxClk. The sampling edge is inverted
when TxClk= 0. In Hardware Mode, the state of pin 7
(CLKE) controls the sampling edge of both TxClk and
RxClk.
HDB3/B8ZS/AMI ENCODER
The encoder is only available in single-rail mode (SR/
DR=1) in Host Mode, or pin 8 set High in Hardware
Mode. In an E1 system, if interface register
CODES=0, HDB3 encoding is selected. Input data
applied to TxPOS/TDATA which contains more than
four consecutive zeros will be removed and replaced
by “000V” or “B00V”, where "B” indicates a pulse conforming with bipolar rule and "V" represents a pulse
violating the rule. In a T1 system, input data with
more than 8 consecutive zeros will be removed and
replaced using B8ZS encoding rule. An example of
Bipolar with 8 Zero Substitution (B8ZS) encoding
scheme is shown in Table 1. With register
CODES=1, AMI coding is selected for both E1 or T1
SINGLE RAIL, DUAL RAIL
Transmit data format can be in dual-rail (SR/DR=1) or
single-rail modes (SR/DR=0). In Hardware Mode, dual or single-rail format is determined by the state of
pin 8. For single-rail mode operation, NRZ data can
be applied to TxPOS/TDATA with TxClk, while TxNEG
input is left unconnected. The transmitter converts
NRZ input data into differential signal for transmission
to the line using low impedance output drivers.
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REV. 1.1.0
modes. In Hardware Mode, HDB3, B8ZS or AMI coding selection is determined by the state of pin 10.
lects active High data and a "1" selects active Low
data. This control bit also selects receive output data
polarity (see Receive Data Invert Mode description).
This feature is not supported in Hardware Mode.
TRANSMIT PULSE SHAPER
The transmit pulse shaper uses high a speed clock
derived from MCLK to synthesize the shape and
width of the transmitted pulse applied to TTIP and
TRING. The internal high speed timing generator
eliminates the need for a tightly controlled transmit
clock TxClk duty cycle. In a T1 system, three control
bits (ECC, ECB and ECA) are available in the Host
Mode, for every channel to select 5 different cable
length pulse settings to meet DSX-1 pulse template.
Table 2 summaries the function of these control bits.
In Hardware Mode, all 4 transmit channels share the
same pulse synthesizer control settings.
TRANSMIT OFF CONTROL
Each transmit channel of the line interface can be
shut down by writing a "1" to TxOFF in the channel
control interface register. In the “Transmitter off”
mode, the entire transmitter is disabled and the outputs at TTIP and TRING are placed in a high impedance state. In Hardware Mode, pins 14 through pin 17
are used for powering down each transmit channel independently. If MCLK is missing, then all transmitters
will be powered down and the outputs are tri-stated.
DRIVER MONITOR
The driver monitor circuit is used for detecting transmit driver failure by monitoring the activity at TTIP
and TRING. Driver failure may be caused by a shortcircuit in the primary of the transformer or system
problems at the input.
TABLE 1: EXAMPLES OF B8ZS ENCODING
CASE 1
PRECEDING PULSE
Input
+
B8ZS
In the Host Mode, when the driver monitor detects no
transitions at TTIP and TRING for more than 128
clock cycles, the DMO bit in the interface register is
set and results in an interrupt (INT) to be generated.
Driver monitor function is not supported in Hardware
Mode.
NEXT 8 BITS
00000000
000VB0VB
AMI Output
+
000+ -0- +
-
00000000
Case 2
Input
TxPOS/TDATA and TxNEG Polarity
B8ZS
In HOST Mode, transmit data at TxPOS/TDATA and
TxNEG can be configured for active Low or active
High operation, by controlling the state of the DATAP
bit in the interface register. Writing a "0" to this bit se-
000VB0VB
AMI Output
-
000- +0+ -
TABLE 2: TRANSMIT EQUALIZER CONTROL
ECC
ECB
ECA
SYSTEM
CABLE LENGTH
0
0
0
T1
0-133 ft.
B8ZS/AMI (DS1)
1:2 or (1:2.45)
0
0
1
T1
133-266 ft.
B8ZS/AMI (DS1)
1:2 or (1:2.45)
0
1
0
T1
266-399 ft.
B8ZS/AMI (DS1)
1:2 or (1:2.45)
0
1
1
T1
399-533 ft.
B8ZS/AMI (DS1)
1:2 or (1:2.45)
1
0
0
T1
533-655 ft.
B8ZS/AMI (DS1)
1:2 or (1:2.45)
1
0
1
Not used
1
1
0
E1
--
HDB3/AMI (E1)
1:2.45
1
1
1
E1
--
HDB3/AMI (E1)
1:2
INTERFACING THE XRT82L34 TO THE LINE
The XRT82L34 in E1 configuration can be transformer coupled to 75Ω coaxial or 120Ω twisted pair lines
CODES
TRANSFORMER RATIO
as shown in Figure 12 and Figure 13 below. For DS1
applications connecting to a 100Ω twisted pair line is
shown in Figure 14.
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
FIGURE 12. XRT82L34 CHANNEL_0 IN AN E1 UNBALANCED 75 Ω APPLICATION - 1:2 OR (1:2.45) TRANSFORMER
TxPOS
TxNEG
TxLineClk
4
3
5
TxPOS_0
TTIP_0
RxPOS
RxNEG
RxLineClk
Loss of signal
99
1
2
Ω
9.1Ω
(6.2Ω)
TxNEG_0
1
T1
BNC
5
1
Coaxial
Cable
2
TxClk_0
TRing_0
100
R1
89
R2
91
RxPOS_0
RxNEG_0
RTIP_0
4
Ω
9.1Ω
(6.2Ω)
94
5
RxClk_0
8
1:2
(1:2.45)
T2
1
R3
18.7Ω
RxLOS_0
RRing_0
95
BNC
1
Coaxial
Cable
2
4
8
1:2
XRT82L34
FIGURE 13. XRT82L34 CHANNEL_0 - E1 120 Ω BALANCED APPLICATION - 1:2 OR (1:2.45) TRANSFORMER
TxPOS
TxNEG
TxLineClk
4
3
5
TxPOS_0
TTIP_0
RxPOS
RxNEG
RxLineClk
Loss of signal
99
1
2
Ω
9.1Ω
(6.2Ω)
TxNEG_0
TxClk_0
TRing_0
100
R5
89
R6
91
RTIP_0
4
Ω
9.1Ω
(6.2Ω)
RxPOS_0
RxNEG_0
1
94
5
RxClk_0
T1
5
8
1:2
(1:2.45)
T2
1
RRing_0
95
8
4
1:2
XRT82L34
19
Twisted
Pair
TRING
RTIP
Twisted
Pair
RRing
R4
30.1Ω
RxLOS_0
TTIP
áç
XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
FIGURE 14. XRT82L34 CHANNEL_0 - DS1 100 Ω BALANCED APPLICATION
TxPOS
TxNEG
TxLineClk
4
3
5
TxPOS_0
TTIP_0
RxNEG
RxLineClk
Loss of signal
100
99
1
2
1 : 2 or 1:2.45
1 T1 5
3Ω
TxNEG_0
TxClk_0
RxPOS_0
TTIP
Twisted
Pair
TRing_0
RxPOS
R2
89
RTIP_0
R3
91
TRING
8
4
3Ω
94
5
T2
1
RTIP
RxNEG_0
R1
25 Ω
RxClk_0
RxLOS_0
Twisted
Pair
RRing_0
95
4
8
1:2
XRT82L34
20
RRing
áç
XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 3: E1 RECEIVER ELECTRICAL CHARACTERISTICS
(Vdd=3.3V±5%, Ta=-40 to 85°C unless otherwise specified)
PARAMETER
MIN
TYP.
MAX
UNIT
TEST CONDITIONS
Number of consecutive
zeros before LOS is set
-
32
-
bit
Input signal level at LOS
18
20
-
dB
12.5
-
-
% ones
Receiver Sensitivity
11
15.5
-
dB
With nominal pulse amplitude of 3.0V for
120Ω and 2.37V for 75Ω application.
With -18dB interference signal added.
Interference Margin
-18
-15
-
dB
With 6dB cable loss
Input Impedance
15
20
-
KΩ
Measured across RTIP/RRing
Jitter Tolerance:
1 Hz
10KHz---100KHz
>64
0.4
-
-
UIpp
ITU G.823
-
20
0.5
KHz
dB
ITU G.736
-
3
-
Hz
ITU G.736
12
18
14
18
22
20
-
dB
dB
dB
ITU G.703
Receiver loss of signal:
LOS De-asserted
Recovered Clock Jitter
Transfer Corner Frequency
Peaking Amplitude
Jitter Attenuator Corner
Frequency(-3dB curve)
Return Loss:
51KHz --- 102KHz
102KHz --- 2048KHz
2048KHz --- 3072KHz
21
75 Ω Cable attenuation @1024KHz
ITU-G.775, ETS1 300 233
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 4: T1 RECEIVER ELECTRICAL CHARACTERISTICS
(Vdd=3.3V±5%, Ta=-40 to 85°C unless otherwise specified)
PARAMETER
MIN
TYP.
MAX
UNIT
TEST CONDITIONS
Number of consecutive
zeros before LOS is set
-
175
-
bit
Input signal level at LOS
15
20
-
dB
12.5
-
-
% ones
Receiver Sensitivity
11
15
-
dB
With nominal pulse amplitude of 3.0V for
100Ω termination.
Interference Margin
-18
-14
-
dB
With 6dB cable loss
Input Impedance
5
20
-
KΩ
Measured across RTIP/RRing
Jitter Tolerance:
1 Hz
10KHz---100KHz
138
0.4
-
-
UIpp
-
12
0.1
KHz
dB
Jitter Attenuator Corner
Frequency(-3dB curve)
-
3
-
Hz
Return Loss:
51KHz --- 102KHz
102KHz --- 2048KHz
2048KHz --- 3072KHz
-
20
25
25
-
dB
dB
dB
Receiver loss of signal:
LOS Clear
Recovered Clock Jitter
Transfer Corner Frequency
Peaking Amplitude
22
75 Ω Cable attenuation @772KHz
ITU-G.775, ETS1 300 233
AT&T Pub 62411
AT&T Pub 62411
áç
XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 5: E1 TRANSMITTER ELECTRICAL CHARACTERISTICS
(Ta=-40 to 85°C, Vdd=3.3V±5%, unless otherwise specified and 1:2 Transformer with 9.1Ω
Ω or 1:2.45
Transformer with 6.2Ω)
Ω)
PARAMETER
MIN
TYP.
MAX
UNIT
TEST CONDITIONS
AMI Output Pulse Amplitude:
75Ω Application
120Ω Application
2.13
2.70
2.37
3.0
2.60
3.30
V
V
Output Pulse Width
224
244
264
ns
Output Pulse Width Ratio
0.95
-
1.05
-
ITU-G.703
Output Pulse Amplitude Ratio
0.95
-
1.05
-
ITU-G.703
Jitter Added by the Transmitter Output
-
0.025
0.05
UIpp
Return Loss:
51KHz --- 102KHz
102KHz --- 2048KHz
2048KHz --- 3072KHz
6
8
8
8
10
10
-
dB
dB
dB
Use transformer with 1:2 ratio and 9.1Ω
resistor in series with each end of primary.
or
Use transformer with 1:2.45 ratio and 6.2Ω
resistor.
Broad Band with jitter free TxClk
applied to the input.
ETSI 300 166, CHPTT
TABLE 6: T1 TRANSMITTER ELECTRICAL CHARACTERISTICS
(Vdd=3.3V±5%, Ta=-40 to 85°C unless otherwise specified)
PARAMETER
MIN
TYP.
MAX
UNIT
TEST CONDITIONS
2.4
3.0
3.60
V
Use transformer with 1:2.45 ratio and measured at DSX-1.
Output Pulse Width
338
350
362
ns
ANSI T1.102
Output Pulse Width Ratio
0.95
-
1.05
ANSI T1.102
Output Pulse Amplitude Ratio
0.95
-
1.05
ANSI T1.102
Jitter Added by the Transmitter Output
-
0.025
0.05
UIpp
Return Loss:
51KHz --- 102KHz
102KHz --- 2048KHz
2048KHz --- 3072KHz
-
6.5
6.5
6.5
-
dB
dB
dB
Return Loss:
51KHz --- 102KHz
102KHz --- 2048KHz
2048KHz --- 3072KHz
-
4.5
4.5
4.5
-
dB
dB
dB
AMI Output Pulse Amplitude:
23
Broad Band with jitter free TxClk
applied to the input.
1:2.45 transformer ratio, RTIP =
RRing= 3Ω, VLine =3.0V
1:2 transformer ratio, RTIP = RRing=
3Ω, VLine =2.7V
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 7: TRANSMIT PULSE MASK SPECIFICATION
Test Load Impedance
75 Ω resistive (Coax)
120 Ω resistive (Twisted Pair)
Nominal peak voltage of a mark
2.37V
3.0V
Peak voltage of a space (no mark)
0 ± 0.237V
0± 0.3V
Nominal pulse width
244ns
244ns
Ratio of positive and negative pulses imbalance
0.95 to 1.05
0.95 to 1.05
FIGURE 15. ITU G.703 E1 PULSE TEMPLATE
24
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 8: DS1 INTERFACE ISOLATED PULSE MASK AND CORNER POINTS.
MINIMUM CURVE
MAXIMUM CURVE
TIME (UI)
NORMALIZED AMPLITUDE
TIME (UI)
NORMALIZED AMPLITUDE
-0.77
-0.05V
-0.77
0.05V
-0.23
-0.05V
-0.39
0.05V
-0.23
0.5V
-0.27
0.8V
-0.15
0.95V
-0.27
1.15V
0.0
0.95V
-0.12
1.15V
0.15
0.9V
0.0
1.05V
0.23
0.5V
0.27
1.05V
0.23
-0.45V
0.35
-0.07V
0.46
-0.45V
0.93
0.05V
0.66
-0.2V
1.16
0.05V
0.93
-0.05V
1.16
-0.05V
FIGURE 16. DSX-1 PULSE TEMPLATE
Normalized Amplitude
25
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 9: DC ELECTRICAL CHARACTERISTICS
(Vdd=3.3V±5%, Ta=25°C unless otherwise specified)
PARAMETER
SYMBOL
MIN
TYP.
MAX
UNITS
Power Supply Voltage
Vdd
3.13
3.3
3.46
V
Input High Voltage
VIH
2.0
-
5.0
V
Input Low Voltage
VIL
-0.5
-
0.8
V
Output High Voltage @ IOH=-5mA
VOH
2.4
-
-
V
Output Low Voltage @IOL=5mA
VOL
-
-
0.4
V
Input Leakage Current (except Input pins with Pull-up
resistor.)
IL
-
-
+ 10
µA
Input Capacitance
CI
-
5.0
-
pF
Output Load Capacitance
CL
-
-
25
pF
TABLE 10: POWER DISSIPATION (XRT82L34 ONLY)
( Vdd=3.3V±5%, Ta=-40 to 85°C unless otherwise specified)
PARAMETER
SYMBO
L
MIN
TYP
MAX
UNITS
CONDITIONS
Power Dissipation
Pd
-
480
530
mW
E1(75Ω) load. All four transmitters running with
PRBS.
Power Dissipation
Pd
-
380
420
mW
E1(120Ω) load. All four transmitters running with
PRBS.
Power Dissipation
Pd
-
550
725
mW
T1(100Ω) load. All four transmitters running with
PRBS.
Power Dissipation
Pd
-
80
100
mW
All Transmitters Powered-down.
TABLE 11: POWER CONSUMPTION (XRT82L34 AND LOAD: PD=VDD X IDD)
( Vdd=3.3V±5%, Ta=-40 to 85°C unless otherwise specified)
PARAMETER
SYMBO
L
MIN
TYP
MAX
UNITS
CONDITIONS
Power Consumption
Pc
-
630
700
mW
E1(75Ω) load. All four transmitters running with
PRBS.
Power Consumption
Pc
-
500
550
mW
E1(120Ω) load. All four transmitters running
with PRBS.
Power Consumption
Pc
-
725
980
mW
T1(100Ω) load. All four transmitters running with
PRBS.
Power Consumption
Pc
-
80
100
mW
All Transmitters Powered-down.
26
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
ABSOLUTE MAXIMUM RATINGS
Storage Temperature
-65°C to + 150°C
Operating Temperature
-40°C to + 85°C
Supply Voltage
-0.5V to + 6.0V
Theta-JA
38° C/W
Theta-JC
6° C/W
TABLE 12: AC ELECTRICAL CHARACTERISTICS
(Vdd=3.3V±5%, Ta=25°C unless otherwise specified)
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS
E1 MCLK Clock Frequency
-
2.048
-
MHz
T1 MCLK Clock Frequency
-
1.544
-
MHz
MCLK Clock Duty Cycle
40
-
60
%
MCLK Clock Tolerance
-
±50
-
ppm
E1 TxClk Clock Period
TCLKP
-
488
-
ns
T1 TxClk Clock Period
TCLKP
-
648
-
ns
TxClk Duty Cycle
TCDU
30
50
70
%
Transmit Data Setup Time
TSU
50
-
-
ns
Transmit Data Hold Time
THO
30
-
-
ns
TxClk Rise Time (10%/90%)
TCLKR
-
-
40
ns
TxClk Fall Time (90%/10%)
TCLKF
-
-
40
ns
RxClk Duty Cycle
RCDU
45
50
55
%
Receive Data Setup Time
RSU
150
-
Receive Data Hold Time
RHO
150
-
-
ns
RxClk to Data Delay
RDY
-
-
40
ns
RxClk Rise Time (10%/90%) with 25pF
Loading.
RCLKR
-
-
40
ns
40
ns
RxClk Fall Time(90%/10%) with 25pF
Loading
RCLKF
27
-
áç
XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
FIGURE 17. TRANSMIT CLOCK AND INPUT DATA TIMING
TCLKR
TCLKF
TCLKP
TxCLK
TxPOS/TDATA
or
TxNEG
Data can be active
high or active low.
THO
TSU
Note: Set TCLKE bit-4 in Command Control Register 0 to select
TxCLK inversion.
FIGURE 18. RECEIVE CLOCK AND OUTPUT DATA TIMING.
RCLKR
RDY
RCLKF
RxCLK
RxPOS
or
RxNEG
RSU
Data can be active
high or active low.
RHO
Note: Set RCLKE bit=5 in Command Control Register 0 to select
MICROPROCESSOR INTERFACE
RxCLK inversion.
The device has 4-bit address ADD[3:0] input and 8-bit
bi-directional data bus ADD[7:0]. The signals required
for a generic microprocessor to access the internal
registers are described in Table 13.
XRT82L34 is equipped with a microprocessor interface for easy device configuration. The parallel port of
the XRT82L34 is compatible with both Intel and Motorola address and data buses.
28
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 13: MICROPROCESSOR INTERFACE SIGNAL
D[7:0]
Data Input (Output): 8 bits bi-directional data bus for register access.
ADD[3:0] Address Input: 4 bit address to select internal register location.
PTS1
PTS2
PCLK
Processor Type Select:
PTS1
PTS2
0
0
8HC11,8081,80C188 (async.)
1
0
Motorola 68K (async.)
0
1
Intel x86 (sync.)
1
1
Intel i906,Motorola 860 (sync.)
Process Clock Input: Input clock for synchronous microprocessor operation. Maximum clock speed is 16MHz.
This pin is internally pulled down for asynchronous microprocessor operation if no clock is present.
ALE_AS Address Latch Input (Address Strobe): With Intel bus timing, the address inputs are latched into the internal
register on the falling edge of ALE. When configured in Motorola bus timing, the address inputs are latched into
the internal register on the falling edge of AS.
CS
RD_DS
Chip Select Input: This signal must be low in order to access the parallel port.
Read Input (Data Strobe): With Intel bus timing, a low pulse on RD selects a read operation when CS pin is
low. When configured in Motorola bus timing, a low pulse on DS indicates a read or write operation when CS
pin is low.
WR_R/W Write Input (Read/Write): With Intel bus timing, a low pulse on WR selects a write operation when CS pin is
low. When configured in Motorola bus timing, a high pulse on R/W selects a read operation and a low pulse on
R/W selects a write operation when CS pin is low.
RDY_DTA Ready Output (Data Transfer Acknowledge Output): With Intel bus timing, RDY is asserted high to indicate the
CK
device has completed a read or write operation. When configured in Motorola bus timing, DTACK is asserted
low to indicate the device has completed a read or write operation.
INT
Interrupt Output: This pin is asserted low to indicate an interrupt caused by an alarm condition in the device
status registers. The activation of this pin can be blocked by the interrupt status register bit.
29
áç
XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 14: MICROPROCESSOR REGISTER MAP
REGISTER
NUMBER
ADDRESS
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Command Control Registers (Read/Write)
0
0000
SR/DR
ATAOS
RCLKE
TCLKE
DATAP
CODES
IMASK
SRESET
1
0001
Reserved
(Set to 0)
Reserved
(Set to 0)
FIFOS
RXJA
TXJA
RXMUTE
EXLOS
ICT
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
DMO0IS
LOS0IS
LVC0IS
TCKL0IS
MDMO0
MLOS0
MLCV0
MTCKL0
Channel 0 Register
2
0010
DMO0
LOS0
LCV0
TCLK0
3
0011
reserved
reserved
4
0100
ECA0
ECB0
ECC0
ALOOP0
DLOOP0
RLOOP0
TAOS0
TxOFF0
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
DMO1IS
LLOSIS1
LCV1
TCKL1IS
MDMO1
MLOS1
MLCV1
MTCKL1
reserved reserved
Channel 1 Register
5
0101
DMO1
LOS1
LCV1
TCLK1
6
0110
reserved
reserved
7
0111
ECA1
ECB1
ECC1
ALOOP1
DLOOP1
RLOOP1
TAOS1
TxOFF1
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
DMO2IS
LLOS2IS
LCV2
TCKL2IS
MDMO2
MLOS2
MLCV2
MTCKL2
reserved reserved
Channel 2 Register
8
1000
DMO2
LOS2
LVC2
TCLK2
9
1001
reserved
reserved
10
1010
ECA2
ECB2
ECC2
ALOOP2
DLOOP2
RLOOP2
TAOS2
TxOFF2
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
DMO3IS
LLOS3IS
LCV3
TCKL3IS
MDMO3
MLOS3
MLCV3
MTCKL3
reserved reserved
Channel 3 Register
11
1011
DMO3
LOS3
LCV3
TCLK3
12
1100
reserved
reserved
13
1101
ECA3
ECB3
ECC3
ALOOP3
DLOOP3
RLOOP3
TAOS3
TxOFF3
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
reserved reserved
30
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 15: COMMAND CONTROL REGISTER 0
COMMAND CONTROL REGISTER 0
PARALLEL PORT ADDRESS: 0000
FUNCTION
REGISTER
TYPE
RESET
VALUE
R/W
0
BIT NO.
NAME
7
SR/DR
Single/Dual Rail:
Writing a "1" to this bit selects transmit and receive data format in
single-rail mode. In this mode, HDB3/B8ZS/AMI encoder and
decoder are available.
Writing a "0" selects dual-rail mode.
6
ATAOS
Automatic Transmit “All Ones”:
Writing a “1” in this bit position enables the automatic transmission
of an all one AMI pattern from the transmitter of any channel that
the receiver of that channel detects an LOS condition.
Writing a “0” in this bit position disables this feature.
R/W
0
5
RCLKE
RxClk Clock Edge: Writing a "1" to this bit selects receive output
data to be updated on positive edge of RxClk.
Writing a "0" to this bit selects the negative edge of RxClk.
R/W
0
4
TCLKE
TxClk Clock Edge: Writing a "1" to this bit selects positive edge of
TxClk to sample input data.
Write "0" to select negative edge.
R/W
0
3
DATAP
DATA Polarity: Writing a "0" to this bit selects transmit input and
receive output data to be active-high.
Write "1" to select active-low.
R/W
0
2
CODES
Coding/Decoding Select: This bit is used in conjunction with SR/DR
bit 1. If SR/DR is "1", writing a "0" to this bit selects HDB3 coding in
E1 and B8ZS in T1. Writing a "1" to this bit position selects AMI
code.
R/W
0
1
GIE
Global Interrupt Enable: Writing a "0" to this bit globally disables
interrupt generation caused by any alarm generated within the line
interface. Write a "1" to enable interrupt generation.
R/W
0
0
SRESET
Software Reset: Writing a "1" to this bit longer than 10µs initiates a
device reset through the microprocessor interface. All internal circuits are placed in the reset state with this bit set to a "1" except the
microprocessor register bits.
R/W
0
31
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 16: COMMAND CONTROL REGISTER 1
COMMAND CONTROL REGISTER 1
PARALLEL PORT ADDRESS: 0001
REGISTER
TYPE
RESET
VALUE
Reserved. Must be set to “0” for proper operation.
R/W
0
Reserved. Must be set to “0” for proper operation.
R/W
0
FIFOS
FIFO Size Select: Writing a "1" to this bit selects 64 bit FIFO
depth. Write "0" to select 32 bit FIFO depth.
R/W
0
4
RxJA
Receive Jitter Attenuator Select: Writing a "1" to this bit selects jitter attenuator in the receive path. If bit 3(TxJA) is also set, jitter
attenuator is disabled.
R/W
0
3
TxJA
Transmit Jitter Attenuator Select: Writing a "1" to this bit selects
jitter attenuator in the transmit path. If bit 4(RxJA) is also set, jitter
attenuator is disabled.
R/W
0
2
RXMUTE
Receive Muting: Writing a "1" to this bit mutes receive data output
to a low state during LOS condition to prevent data chattering.
R/W
0
1
EXLOS
Extended LOS: Writing a "1" to this bit extends the number of
zeros at the input to 4096 bits before LOS is declared.
R/W
0
0
ICT
In-Circuit-Testing: Writing a "1" to this bit causes all output pins to
be in high impedance mode for in-circuit testing. The software
ICT function is equivalent to connecting pin 20 to ground.
R/W
0
BIT NO.
NAME
7
--
6
--
5
FUNCTION
32
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 17: CHANNEL STATUS REGISTER
CHANNEL STATUS REGISTER
PARALLEL PORT ADDRESS CHANNEL 0: 0010
PARALLEL PORT ADDRESS CHANNEL 1: 0101
PARALLEL PORT ADDRESS CHANNEL 2: 1000
PARALLEL PORT ADDRESS CHANNEL 3: 1011
REGISTER
TYPE
RESET
VALUE
Driver Monitor Output: This bit is set to a "1" to indicate current DMO is
detected. Any change in the state of this bit causes an interrupt to be generated. Reading this register bit does not clear the DMO bit.
R
0
LOSn
Loss of Signal: This bit is set to a "1" to indicate current LOS condition is
detected. Any change in the state of this bit causes an interrupt to be generated. Reading this register bit does not clear the LOS bit.
R
0
5
LCVn
Line Code Violation: This bit is set to a "1" to indicate current LCV condition
is detected. Any change in the state of this bit causes an interrupt to be generated. Reading this register bit does not clear the LCV bit.
R
0
4
TCKLn
Transmit Clock Loss: This bit is set to a "1" to indicate current TxClk clock
loss is detected. Any change in the state of this bit causes an interrupt to be
generated. Reading this register bit does not clear the TCKL bit.
R
0
BIT NO.
SYMBOL
7
DMOn
6
FUNCTION
3
DMOnIS Driver Monitor Output: This bit is set to a "1" every time the state of DMO
status changes since last read. This bit is cleared by a read operation.
RUR
0
2
LOSnIS Latched- Loss of signal: This bit is set to a "1" every time the state of LOS
changes since last read. This bit is cleared by a read operation.
RUR
0
1
LCVnIS
Latched- Line Code Violation: This bit is set to a "1" every time the state of
LCV changes since last read. This bit is cleared by a read operation.
RUR
0
0
TCLKnIS Latched-Transmit Clock Loss. This bit is set to a "1" every time the state of
TCKL changes since last read. This bit is cleared by a read operation.
RUR
0
NOTE: n = channel number 0 to 3.
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 18: CHANNEL MASK REGISTER
CHANNEL MASK REGISTER
PARALLEL PORT ADDRESS CHANNEL 0: 0011
PARALLEL PORT ADDRESS CHANNEL 1: 0110
PARALLEL PORT ADDRESS CHANNEL 2: 1001
PARALLEL PORT ADDRESS CHANNEL 3: 1100
Bit No.
Name
7
--
6
Function
Register Type
Reset Value
This bit is reserved.
R/W
0
--
This bit is reserved.
R/W
0
5
--
This bit is reserved.
R/W
0
4
--
This bit is reserved.
R/W
0
3
DMOnIS
Driver Monitor Output Interrupt Status: Writing a "1" to this
bit enables DMO alarm interrupt generation.
R/W
0
2
LOSnIS
Loss of Signal Interrupt Status: Writing a "1" to this bit
enables LOS alarm interrupt generation.
R/W
0
1
LCVnIS
Line Code Violation Interrupt Status: Writing a "1" to this
bit enables LCV interrupt generation.
R/W
0
0
TCKLnIS
Transmit Clock Loss Interrupt Status: Writing a "1" to this
bit enables TxClk clock loss interrupt generation.
R/W
0
NOTE: n = channel number 0 to 3.
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 19: CHANNEL CONTROL REGISTER
CHANNEL CONTROL REGISTER
Parallel Port Address Channel 0: 0100
Parallel Port Address Channel 1: 0111
Parallel Port Address Channel 2: 1010
Parallel Port Address Channel 3: 1101
BIT NO.
SYMBOL
FUNCTION
REGISTER TYPE
RESET VALUE
7
ECAn
These 3 control bits are used to control the transmit pulse
shape for T1 and E1 operations. See Table 2 for details.
R/W
0
6
5
ECBn
ECCn
R/W
R/W
0
0
4
LLOOPn
Local Loop-Back: Writing a "1" to this bit enables Analog
Local Loop-Back. Simultaneously setting RLOOP High is
not allowed.
R/W
0
3
DLOOPn
Digital Loop-Back: Writing a "1" to this bit enables Digital
Loop-Back.
R/W
0
2
RLOOPn
Remote Loop-Back: Writing a "1" to this bit enables
Remote Loop-back. Simultaneously setting LLOOP High
is not allowed.
R/W
0
1
TAOSn
Transmit All Ones: Writing a "1" to this bit enables the All
Ones AMI signal to be transmitted to the line.
R/W
0
0
TxOFFn
Transmitter Off: Writing a "1" to this bit powers down the
transmitter and places the corresponding output driver in
a high impedance mode.
R/W
0
NOTE: n = channel number 0 to 3.
Microprocessor Interface I/0 Timing
minimum external glue logic and is compatible with
the timings of the 8051 or 80C188 with an 8-16 MHz
clock frequency, and with the timings of x86 or I960
family or microprocessors. The interface timing
shown in Figure 19 and Figure 20 is described in
Table 20.
Intel Interface Timing
The signals used for the Intel microprocessor interface are: Address Latch Enable (ALE), Read Enable
(RD), Write Enable (WR), Chip Select (CS), Address
and Data bits. The microprocessor interface uses
35
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
FIGURE 19. INTEL INTERFACE TIMING (READ)
t64
t65
ALE_AS
A[8:0]
Address of Target Register
t68
CS
t67
D[7:0]
Not Valid
RD_DS
t69
WR_R/W
Valid
t66
t701
RDY_DTCK
t70
FIGURE 20. INTEL INTERFACE TIMING (WRITE)
t64
t65
ALE_AS
A[8:0]
CS
D[7:0]
Address of Target Register
t770
t71
t72
Data to be Written
RD_DS
t73
t66
WR_R/W
36
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 20: INTEL INTERFACE TIMING SPECIFICATIONS
SYMBOL
PARAMETER
MIN
TYP
MAX
CONDITION
t64
A8 - A0 Setup Time to ALE_AS
Low
4
ns
t65
A8 - A0 Hold Time from ALE_AS
Low.
2
ns
Intel Type Read Operation
t66
RDS_DS Pulse Width
260
ns
t67
Data Valid from RDS_DS* Low.
240
ns
t68
Data Bus Floating from
RDS_DS* High
2
ns
t69
ALE to RD Time
4
ns
t701
RD Time to "NOT READY" (e.g.,
RDY_DTCK toggling "Low")
t76
Minimum Time between Read
Burst Access (e.g., the rising
edge of RD to falling edge of RD)
145
ns
60
ns
160
ns
Intel Type Write Operations
t71
Data Setup Time to WR_R/W
High
t72
Data Hold Time from WR_R/W
High
0
ns
t73
High Time between Reads and/
or Writes
60
ns
t74
ALE to WR Time
4
ns
t77
Min Time between Write Burst
Access (e.g., the rising edge of
WR to the falling edge of WR)
60
ns
t770
CS Assertion to falling edge of
WR_R/W
20
ns
Motorola Interface Timing
with the timing of a Motorola 68000 microprocessor
family with up to 16.67 MHz clock frequency. The interface timing is shown in Figure 21, Figure 22 and
Figure 23. The I/O specifications are shown in
Table 21.
The signals used in the Motorola microprocessor interface mode are: Address Strobe (AS), Data Strobe
(DS), Read/Write Enable (R/W), Chip Select (CS),
Address and Data bits. The interface is compatible
37
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
FIGURE 21. MICROPROCESSOR INTERFACE TIMING - MOTOROLA TYPE PROGRAMMED I/O READ OPERATION
t78
ALE_AS
A[8:0]
Address of Target Register
CS
D[7:0]
Valid Data
Not Valid
RD_DS
WR_RW
t79
RDY_DTCK
t80
FIGURE 22. MICROPROCESSOR INTERFACE TIMING - MOTOROLA TYPE PROGRAMMED I/O WRITE OPERATION
t78
ALE_AS
A[8:0]
CS
D[7:0]
Address of Target Register
t81
Data to be Written
RD_DS
WR_RW
t82
RDY_DTCK
.
FIGURE 23. MICROPROCESSOR INTERFACE TIMING - RESET PULSE WIDTH
t90
Reset
38
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
TABLE 21: MOTOROLA INTERFACE TIMING SPECIFICATION
SYMBOL
PARAMETER
MIN
TYP
MAX
UNITS
Microprocessor Interface - Motorola Read Operations (see Figure 21)
t78
A3 - A0 Setup Time to falling edge of ALE_AS
5
ns
t79
Rising edge of RD_DS to rising edge of RDY_DTCK delay
0
ns
t80
Rising edge of RDY_DTCK to tri-state of D[7:0]
0
ns
Microprocessor Interface - Motorola Write Operations (see Figure 22)
t78
A3 - A0 Setup Time to falling edge of ALE_AS
5
ns
t81
D[7:0] Setup Time to falling edge of RD_DS
10
ns
t82
Rising edge of RD_DS to rising edge of RDY_DTCK delay
0
ns
30
ns
Reset pulse width - both Motorola and Intel Operations (see Figure 23)
t90
Reset pulse width
39
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
3. The "Maximum Tolerable Input Jitter Amplitude"
values reflect the amount of Jitter that will cause
the XRT82L34 to experience a Bit Error Rate (BER)
of 1x10-9.
4. 64UI-pp is the maximum amount of "Input Jitter
Amplitude" that the Test Equipment used (W&G
ANT-20) can insert into the DS1 line signal.
5. Measurements were performed with 6.4dB of cable
loss inserted into the Receive Line signal (between
the ANT-20 and the Receive Input of the device).
JITTER TOLERANCE IN DS1 APPLICATIONS
Input Jitter Tolerance Measurements are presented
for the following two situations.
1. The Jitter Attenuator within the Channel-UnderTest is disabled.
2. The Jitter Attenuator within the Channel-UnderTest is enabled and configured to operate in the Receive Path.
The results of the Input Jitter Tolerance Measurements are plotted in Figure 24.
FIGURE 24. INPUT JITTER TOLERANCE PERFORMANCE OF THE XRT82L34, FOR DS1 APPLICATIONS, WITH THE JITATTENUATOR DISABLED
TER
DS1 Jitter Tolerance: Jitter Attenuator Disabled
Input Jitter Amplitude (UIpp)
100
10
;57;5/67#'64#-LWWHU#7ROHUDQFH=
1R#-$
Bellcore GR-499-CORE (Cat I): Jitter
Tolerance Requirements for DS1
1
Bellcore GR-499-CORE (Cat II): Jitter
Tolerance Requirements for DS1
0.1
1
10
100
1000
10000
100000
Jitter Frequency (Hz)
Bellcore GR-499-CORE requires that the Jitter Tolerance Measurements always be above both curves.
The curve with square boxes and the curve with Triangular boxes are the Jitter Tolerance Requirements
per Bellcore Category I and II GR-499-CORE (for
DS1 Applications).
The Maximum Jitter Tolerance measurements for the
XRT82L38 (for DS1 applications) is shown by the
curve marked with the Diamond boxes.
40
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
NOTES:
1. The "Maximum Tolerable Input Jitter Amplitude"
values reflect the amount of Jitter that will cause
the XRT82L34 to experience a Bit Error Rate (BER)
of 1x10-9.
2. 64UI-pp is the maximum amount of "Input Jitter
Amplitude" that the Test Equipment used (W&G
ANT-20) can insert into the DS1 line signal.
3. Measurements were performed with 6.4dB of cable
loss inserted into the Receive Line signal (between
the ANT-20 and the Receive Input of the device).
JITTER ATTENUATOR ENABLED AND CONFIGURED TO OPERATE IN THE RECEIVE PATH
The results of the Input Jitter Tolerance Measurements with the Jitter Attenuator enabled and configured to operate in the receive path are plotted in
Figure 25.
FIGURE 25. INPUT JITTER TOLERANCE CAPABILITY OF THE XRT82L34 FOR DS1 APPLICATIONS WITH THE JITTER
ATTENUATOR ENABLED AND OPERATING IN THE RECEIVE PATH
DS1/E1 Jitter Tolerance: Jitter Attenuator in Receive Path
Input Jitter Amplitude (UIpp)
100
10
;57;5/67#-LWWHU#7ROHUDQFH
0#'642-$#LQ#5[#SDWK
Bellcore GR-499-CORE (Cat I):
Jitter Tolerance Requirements for
DS1
1
Bellcore GR-499-CORE (Cat II):
Jitter Tolerance Requirements for
DS1
0.1
1
10
100
1000
10000
Jitter Frequency (Hz)
41
100000
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
NOTE: No cable loss was applied to the Receive Line Signal, during these measurements.
JITTER TRANSFER CHARACTERISTICS OF THE
XRT82L34 CONFIGURED TO OPERATE IN THE
DS1 MODE
FIGURE 26. JITTER TRANSFER CHARACTERISTICS OF THE XRT82L34 FOR DS1 APPLICATIONS WITH THE JITTER
ATTENUATOR ENABLED AND OPERATING IN THE RECEIVE PATH
J i tter Transfer Characteri sti cs o f the XRT8 2 L3 4 Devi c e (DS1 Appl i cati o ns - J A Enabl ed, Rx P ath)
0
-5
-10
Jitte r Gain (dB)
-15
-20
-25
Jit ter G ain (dB)
-30
-35
-40
-45
-50
1
10
100
Jitte r Fre qu e n cy, Hz
42
1000
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
APPENDIX A
contains an executable file called xrt82L24_34.exe.
This file contains the executable code used to run the
GUI software interface. Figure 27 is a picture of the
GUI software interface and its configuration options.
For more information on the XRT82L/L24 evaluation
kit GUI software, see the XRT82L34/L24EVAL User
Manual.
XRT82LL34 AND XRT82L24 EVALUATION KIT
(XRT82L34/L24EVAL)
The XRT82L34/L24EVAL is a complete printed circuit
board for characterizing Exar's XRT82L34 or
XRT82L24 products. This application board combines a proven PC board layout with optimized analog
and digital interface circuitry. The XRT82L34/
L24EVAL comes with a CD ROM or Floppy Disk that
FIGURE 27. XRT82L34/L24 GUI SOFTWARE INTERFACE FOR EVALUATING THE XRT82L24/L34EVAL APPLICABOARD
TION
The Evaluation Kit Contains the Following:
· XRT82L34 or XRT82L24 100-Pin TQFP
· XRT82L34/L24EVAL Application Board
· XRT82L34/L24EVAL User Manual
· XRT82L34/L24 GUI Evaluation Software (CD ROM
or Floppy Disk)
· XRT82L34 Datasheet
43
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
FIGURE 28. PHOTOGRAPH OF THE XRT82L34/L24EVAL APPLICATION BOARD
44
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XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
FIGURE 29. BLOCK LAYOUT OF THE XRT82L34/L24EVAL APPLICATION BOARD
áç
+ 5.0V
CORPORATION AD INFINITUM
C
Transformer
J16
LINE 0
Osillator
XRT82L34IV
á
J14
LINE 1
J13
Transformer
PLD
µP
Emulator
ε XILINX
GND
Transformer
975H
16.3840M
M
*PC
J115
J12
LINE 2
J11
Transformer
PC Parallel Connector
J18
J17
XRT82L34
XRT82L24
45
EVAL PCB
LINE 3
áç
XRT82L34
QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
ORDERING INFORMATION
PART NUMBER
PACKAGE
OPERATING TEMPERATURE RANGE
XRT82L34IV
100 Lead TQFP (14 x 14 x 1.4mm)
-40°C to +85°C
PACKAGE DISSIPATION
Theta-JA 38° C/W
Theta-JC 6° C/W
PACKAGE DIMENSIONS 100 LEAD TQFP 14X14MM
D
D1
75
51
76
50
D1
100
26
1
25
A2
B
e
C
A
Seating Plane
α
A1
L
NOTE: The control dimension is the millimeter column
INCHES
MILLIMETERS
SYMBOL
MIN
MAX
MIN
MAX
A
0.055
0.063
1.40
1.60
A1
0.002
0.006
0.05
0.15
A2
0.053
0.057
1.35
1.45
B
0.007
0.011
0.17
0.27
C
0.004
0.008
0.09
0.20
D
0.622
0.638
15.80
16.20
D1
0.547
0.555
13.90
14.10
e
0.020 BSC
0.50 BSC
L
0.018
0.030
0.45
0.75
α
0°
7°
0°
7°
46
D
XRT82L34
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QUAD T1/E1/J1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.0
REVISION HISTORY
Rev. P1.0.1 to P1.0.5 editor revisions
Rev. P1.0.6 Power Consumption, Table 10, changed to Tables 10 and 11, Power Dissipation and Power
Consumption. Changed channel indicators for pin names (example TxClk0 = TxClk_0). Added both 1:2
and 1:2.45 output transformer applications info, modified table 2 and figures 12, 13 and 14. Updated Return Loss numbers in Table 5.
Rev. 1.0.0 Removed “Preliminary” designation. Corrected receive side transformer ratio in figures 12, 13
and 14 from 2:1 to 1:2.
Rev. 1.1.0 Table 19: Channel Control Register, change bit 7 to ECAn and bit 5 to ECCn.
NOTICE
EXAR Corporation reserves the right to make changes to the products contained in this publication in order
to improve design, performance or reliability. EXAR Corporation assumes no responsibility for the use of
any circuits described herein, conveys no license under any patent or other right, and makes no representation that the circuits are free of patent infringement. Charts and schedules contained here in are only for
illustration purposes and may vary depending upon a user’s specific application. While the information in
this publication has been carefully checked; no responsibility, however, is assumed for inaccuracies.
EXAR Corporation does not recommend the use of any of its products in life support applications where
the failure or malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation receives, in writing, assurances to its satisfaction that: (a) the risk of injury
or damage has been minimized; (b) the user assumes all such risks; (c) potential liability of EXAR Corporation is adequately protected under the circumstances.
Copyright 2001 EXAR Corporation
Datasheet June 2001.
Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited.
47