EXAR XRT82L24A

áç
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
AUGUST 2004
REV. 1.1.2
GENERAL DESCRIPTION
• Per-channel transmit power shutdown
The XRT82L24A is a fully integrated Quad (four channels) short-haul line interface unit for 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.
• Tri-state transmit output capability
XRT82L24A is a low power CMOS device operating
on a single 3.3V supply with 5V tolerant digital inputs.
• Meets or exceeds G.783 and G.823 Jitter Specifications
FEATURES
• Fully integrated quad, short-haul PCM transceivers
for E1 applications.
• 3.3V or 5.0V Logic level inputs
• On Chip Receive Equalizer and Transmit Pulse
Shaper for CEPT 75Ω and 120Ω line terminations
• On chip clock recovery circuit
• On chip per-channel driver failure monitoring circuit
• On chip HDB3/B8ZS/AMI encoder/decoder functions
• Supports Gapped Clock for Multiplexer Mapper
Applications
• 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; ETSI 300-166
• Single +3.3V Supply Operation
• New Patent# 6,313,671B1 Low Power IC I/O Buffer
APPLICATIONS
• Digital cross connects (DSX-1)
• Channel Banks
• Transformer or capacitor coupled receiver inputs
• Crystal-less jitter attenuator can be selected in the
transmit or receive path
• High speed data transmission line cards
• E1 Multiplexer
• Public switching systems and PBX interfaces
• High receiver interference immunity
FIGURE 1. BLOCK DIAGRAM OF THE XRT82L24A E1 LIU (HOST MODE)
Driver
Monitor
TxClk_n/RZData_n
TxPOS_n/TDATA_n
TxNEG_n
HDB3
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
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/TxOFF_0
ALE_AS/TxOFF_2
CS/TxOFF_3
RD_DS/TxOFF_1
HW/HOST
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (510) 668-7000 • FAX (510) 668-7017 • www.exar.com
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
FIGURE 2. BLOCK DIAGRAM OF THE XRT82L24A T1/E1/J LIU (HARDWARE MODE)
Driver
Monitor
One of four channels
TxClk_n/RZData
TxPOS _n/TDATA_n
TxNEG_n
HDB3
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
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]
ADD[1]
ADD[2]
ADD[3]/RxMute
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
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XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
ORDERING INFORMATION
PART NUMBER
PACKAGE
OPERATING TEMPERATURE RANGE
XRT82L24AIV
100 Lead TQFP (14 x 14 x 1.4mm)
-40°C to +85°C
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
75
100 Lead TQFP
50
26
51
RxPOS_1/RxData_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/RZData_0
RxLOS_0
TxNEG_0
TxPOS_0/TData_0
TxClk_0
Reset
PTS1/ClkE
PTS2/SR/DR
HW/HOST
PClk/Codes
AGND
AVDD
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/RZData_1
76
100
RxPOS_0/RData_0
RxNEG_0/LCV_0
DVDD
DGND
AGND
RRing_0
RTIP_0
AVDD
TGND_0
TRing_0
TVDD_0
TTIP_0
VDD
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 XRT82L24A
3
RxClk_3/RZData_3
RxLOS_3
TxNEG_3
TxPOS_3/TData_3
TxClk_3
A[0]
A[1]
A[2]
A[3]/RxMute
MClk
GND
VDD
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/RZData_2
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
TABLE OF CONTENTS
GENERAL DESCRIPTION ................................................................................................. 1
FEATURES ....................................................................................................................................................
APPLICATIONS ..............................................................................................................................................
Figure 1. Block Diagram of the XRT82L24A E1 LIU (Host Mode) .........................................................
Figure 2. Block Diagram of the XRT82L24A T1/E1/J LIU (Hardware Mode) ........................................
Figure 3. Pin Out of the XRT82L24A .......................................................................................................
1
1
1
2
3
TABLE OF CONTENTS ....................................................................................................... I
PIN DESCRIPTION ............................................................................................................. 4
RECEIVER SECTIONS ....................................................................................................................................
TRANSMITTER SECTIONS ..............................................................................................................................
MICROPROCESSOR INTERFACE ......................................................................................................................
CLOCKS .......................................................................................................................................................
JITTER ATTENUATOR ....................................................................................................................................
CONTROL .....................................................................................................................................................
POWER SUPPLIES AND GROUNDS .................................................................................................................
4
4
5
7
7
7
8
SYSTEM-FUNCTIONAL DESCRIPTION ......................................................................... 10
RECEIVER .................................................................................................................................................. 10
JITTER ATTENUATOR .................................................................................................................................. 10
GAPPED CLOCK (JA MUST BE ENABLED IN THE TRANSMIT PATH) ................................................................. 10
TABLE 1: MAXIMUM GAP WIDTH FOR MULTIPLEXER/MAPPER APPLICATIONS ............................................... 10
HDB3/AMI DECODER ................................................................................................................................. 10
RECEIVER LOSS OF SIGNAL (LOS) .............................................................................................................. 10
CONDITIONS FOR DECLARING AND CLEARING LOS IN THE E1 MODE. ............................................................ 11
RECEIVE DATA MUTING .............................................................................................................................. 11
LOOP-BACK MODES .............................................................................................................................. 11
REMOTE LOOP-BACK (RLOOP) MODE ...................................................................................................... 11
DIGITAL LOCAL LOOP-BACK (DLOOP) MODE ............................................................................................... 11
ANALOG LOCAL LOOP-BACK (ALOOP) MODE .............................................................................................. 12
Figure 4. Remote Loop-Back with jitter attenuator selected in receive path .................................... 12
Figure 5. Remote Loop-Back with jitter attenuator selected in transmit path .................................. 12
Figure 6. Digital Local Loop-Back with option to transmit all “ones” to the line (JA selected & in receive path) .............................................................................................................................. 13
Figure 7. Digital Local Loop-Back with option to transmit all “ones” to the line (JA selected & in
transmit path) ......................................................................................................................... 13
Figure 8. Analog Local Loop-Back signal flow Jitter Attenuator selected & in Receive path ........ 14
Figure 9. Analog Local Loop-Back signal flow Jitter Attenuator selected & in transmit path ........ 14
RESET OPERATION ..................................................................................................................................... 14
RECEIVER MODES OF OPERATION ............................................................................................................... 14
RECEIVE DATA INVERT MODE ..................................................................................................................... 14
Figure 10. Data changes on rising edge of Clk and Data is sampled on falling edge ..................... 15
Figure 11. Data changes on falling edge of Clk and is sampled on rising edge .............................. 15
TRANSMIT CLOCK SAMPLING EDGE ............................................................................................................. 15
SINGLE RAIL, DUAL RAIL .............................................................................................................................. 15
TRANSMIT ALL ONES (TAOS) ..................................................................................................................... 15
HDB3/AMI ENCODER ................................................................................................................................. 15
TRANSMIT PULSE SHAPER .......................................................................................................................... 16
DRIVER MONITOR ....................................................................................................................................... 16
TRANSMIT OFF CONTROL ............................................................................................................................ 16
INTERFACING THE XRT 82L24A TO THE LINE .............................................................................................. 16
Figure 12. XRT 82L24A Channel 1in an E1 unbalanced 75 W application ........................................ 16
Figure 13. XRT 82L24A Channel 1 - E1 120 W balanced application ................................................. 17
TABLE 2: E1 RECEIVER ELECTRICAL CHARACTERISTICS ............................................................................. 18
I
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XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
TABLE 3: E1 TRANSMITTER ELECTRICAL CHARACTERISTICS .......................................................................
TABLE 4: TRANSMIT PULSE MASK SPECIFICATION ......................................................................................
Figure 14. ITU G.703 E1 Pulse Template ..............................................................................................
TABLE 5: DC ELECTRICAL CHARACTERISTICS ............................................................................................
TABLE 6: POWER CONSUMPTION (TA=-40°C TO 85°C, VDD=3.3V + 5%, UNLESS OTHERWISE SPECIFIED.) ..
19
19
20
20
21
ABSOLUTE MAXIMUM RATINGS ................................................................................... 21
TABLE 7: AC ELECTRICAL CHARACTERISTICS ............................................................................................
Figure 15. Transmit Clock and Input Data Timing ..............................................................................
Figure 16. Receive Clock and Output Data Timing. ............................................................................
TABLE 8: MICROPROCESSOR INTERFACE SIGNAL ........................................................................................
TABLE 9: MICROPROCESSOR REGISTER MAP .............................................................................................
TABLE 10: COMMAND CONTROL REGISTER 0 .............................................................................................
TABLE 11: COMMAND CONTROL REGISTER 1 .............................................................................................
TABLE 12: CHANNEL STATUS REGISTER ....................................................................................................
TABLE 13: CHANNEL MASK REGISTER .......................................................................................................
TABLE 14: CHANNEL CONTROL REGISTER ................................................................................................
Figure 17. Intel Interface Timing (Read) ...............................................................................................
Figure 18. Intel Interface Timing (Write) ...............................................................................................
TABLE 15: INTEL INTERFACE TIMING SPECIFICATIONS .................................................................................
Figure 19. Microprocessor Interface Timing - Motorola Type Programmed I/O Read Operation ...
Figure 20. Microprocessor Interface Timing - Motorola Type Programmed I/O Write Operation ...
Figure 21. Microprocessor Interface Timing - Reset Pulse Width .....................................................
TABLE 16: MOTOROLA INTERFACE TIMING SPECIFICATION ..........................................................................
JITTER TOLERANCE ....................................................................................................................................
Figure 22. Receive Maximum Jitter Tolerance ....................................................................................
Figure 23. Receiver Jitter Transfer Function (Jitter Attenuator disabled) ........................................
Figure 24. Jitter Attenuation Function .................................................................................................
ORDERING INFORMATION ............................................................................................................................
PACKAGE DIMENSIONS 100 LEAD TQFP 14X14MM .....................................................................................
REVISION HISTORY .....................................................................................................................................
II
21
22
22
23
24
25
26
27
28
29
30
30
31
32
32
33
33
34
34
35
35
36
36
37
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
PIN DESCRIPTION
PIN DESCRIPTIONS
PIN #
NAME
TYPE
DESCRIPTION
RECEIVER SECTIONS
1
25
51
75
RxCLK_0/RZData_0
RxCLK_1/RZData_1
RxCLK_2/RZData_2
RxCLK_3/RZData_3
O
Receiver_n Clock Output
Rzdata Output:
In Data Slicer Mode, (register 0, bit 7 = 1) or in Hardware Mode when MClk is
absent, this signal is OR-ed RZdata after the slicers.
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
26
50
76
RxPOS_0/RData_0
RxPOS_1/RData_1
RxPOS_2/RData_2
RxPOS_3/RData_3
O
Receiver 1 Positive Data Output:
In dual-rail mode, this signal is the receive P-rail output data.
Receiver 1 NRZ Data Output:
In single-rail mode, this signal is the receive output data.
99
27
49
77
RxNEG_0/LCV_0
RxNEG_1/LCV_1
RxNEG_2/LCV_2
RxNEG_3/LCV_3
O
Receiver_n Negative Data Output:
In dual-rail mode, n-rail data are sent to the framer.
Line Code Violation Output - Channel_n:
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".
95
31
45
81
RRing_0
RRing_1
RRing_2
RRing_3
I
Receiver_n Differential Negative Input.
94
32
44
82
RTIP_0
RTIP_1
RTIP_2
RTIP_3
I
Receiver_n Differential Positive Input.
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.
TRANSMITTER SECTIONS
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 nrail input data for transmitter 0. In single-rail mode, this pin can be left unconnected.
4
22
54
72
TxPOS_0/TData_0
TxPOS_1/TData_1
TxPOS_2/TData_2
TxPOS_3/TData_3
I
Transmitter_n Positive Data Input. In dual-rail mode, this signal is the p-rail
input data for transmitter 0.
Transmitter 0 Data Input. In single-rail mode, this pin is used as the NRZ input
data for transmitter 0.
4
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XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
PIN DESCRIPTIONS
PIN #
NAME
TYPE
DESCRIPTION
5
21
55
71
TxClk_0
TxClk_1
TxClk_2
TxClk_3
I
Transmitter_n Clock Input: E1 rate at 2.048MHz ± 50ppm.
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. If TxClk is active
while MClk is not present, TxPOS and TxNEG accepts NRZ data input and the
transmit pulse width is determined by TxClk clock duty cycle. If TxClk is tied to
“Low”, TxPOS and TxNEG input accepts RZ data format and the pulse width is
determined by the duty cycle of the input data. In RZ Mode, single-rail data format is not supported.
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_0 is tied “Low” for more than 10 µs, the transmitter will be powered
down and the output will be tri-stated.
14
15
16
17
TxOFF_0
TxOFF_1
TxOFF_2
TxOFF_3
I
Powered-down Transmitter_n:
In 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.
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.
MICROPROCESSOR INTERFACE
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
PTS1
I
Processor Type Select bit 1:
Host Mode
In Host Mode the appropriate bits are set in the command mode
ClkE
I
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.)
Hardware Mode:
The state of the ClkE input controls the sampling edge of both TxClk and RxClk.
A “1” selects the positive edge of TxClk and RxClk
A “0” selects the negative edge of TxClk and RxClk.
5
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
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REV. 1.1.2
PIN DESCRIPTIONS
PIN #
NAME
TYPE
DESCRIPTION
8
PTS2
I
Host Mode:
Processor Type Select Input bit 2:
See description for pin 7.
Hardware Mode
Single rail/Dual Rail Control
Connect this pin “Low” to select transmit and receive data format in dual-rail
mode. In this mode, HDB3 encoder and decoder are not available. Connect this
pin "High" to select single-rail data format.
NOTE: Internally pulled -downwith a 50kΩ resistor.
I
Mode Control Input:
SR/DR
9
HW/HOST
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.
10
PCLK
I
I
Codes
Processor Clock Input.
Input clock for synchronous microprocessor operation. Maximum clock rate is
16 MHz. This pin is internally pulled-up for asynchronous microprocessor interface when no clock is present.
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.
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.
6
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XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
PIN DESCRIPTIONS
PIN #
NAME
TYPE
DESCRIPTION
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.
67
68
69
70
A[3]
A[2]
A[1]
A[0]
I
Host Mode, Microprocessor Interface Address Bus [3]
Host Mode, Microprocessor Interface Address Bus [2]
Host Mode, Microprocessor Interface Address Bus [1]
Host Mode, Microprocessor Interface Address Bus [0].
56
57
58
59
60
61
62
63
D[7]
D[6]
D[5]
D[4]
D[3]
D[2]
D[1]
D[0]
I/O
MCLK
I
Master Clock Input.
This signal is an independent 2.048MHz clock 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 absent, all receive channels perform as analog front-end (AFE). The
OR-ed RZ data is also available at RxClk output in this mode, instead. The
clock recovery function is disabled.
Data Bus[7:0].
Microprocessor read/write data bus pins.
CLOCKS
66
JITTER ATTENUATOR
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.
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.
8
SR/DR
I
Single rail/Dual Rail Control:
Hardware Mode
Connect this pin “Low” to select transmit and receive data format in dual-rail
mode. In this mode, HDB3 encoder and decoder are not available. Connect this
pin "High" to select single-rail data format.
NOTE: Internally pulled -down 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.
CONTROL
7
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
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REV. 1.1.2
PIN DESCRIPTIONS
PIN #
NAME
TYPE
DESCRIPTION
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
DLoop-back Mode Select.
In 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 and Low to
select remote loop-back. Digital Loop-back is not supported in Hardware Mode.
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 loop-back operation. Remote or
local loop-back is determined by pin 58 setting.
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.
POWER SUPPLIES AND GROUNDS
12
AVDD
****
Analog Positive Supply(3.3V± 5%)
28
DVDD
****
Digital Positive Supply(3.3V± 5%)
33
DVDD
****
Digital Positive Supply(3.3V± 5%)
90
36
40
86
TVDD_0
TVDD_1
TVDD_2
TVDD_3
****
Transmitter_n Analog Positive Supply(3.3V± 5%).
43
AVDD
****
Analog Positive Supply(3.3V± 5%)
48
DVDD
****
Digital Positive Supply(3.3V± 5%)
64
DVDD
****
Digital Positive Supply(3.3V± 5%)
78
DVDD
****
Digital Positive Supply(3.3V± 5%)
11
AGND
****
Analog Ground
13
DGND
****
Digital Ground
29
DGND
****
Digital Ground
30
DGND
****
Digital Ground
92
34
42
84
TGND_0
TGND_1
TGND_2
TGND_3
****
Transmitter_n Analog Ground.
8
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XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
PIN DESCRIPTIONS
PIN #
NAME
TYPE
DESCRIPTION
38
AGND
****
Analog Ground
46
AGND
****
Analog Ground
47
DGND
****
Digital Ground
65
DGND
****
Digital Ground
79
DGND
****
Digital Ground
80
AGND
****
Analog Ground
83
AVDD
****
Analog Positive Supply(3.3V± 5%)
88
AVDD
****
Analog Positive Supply(3.3V± 5%)
93
AVDD
****
Analog Positive Supply(3.3V± 5%)
96
AGND
****
Analog Ground
97
DGND
****
Digital Ground
98
DVDD
****
Digital Positive Supply(3.3V± 5%)
9
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
SYSTEM-FUNCTIONAL DESCRIPTION
erate 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
the narrow bandwidth requirement as specified in
ITU- G.736 and ITU- I.431standards.
A simplified single channel block diagram of the XRT
82L24A is presented in Figure 1. The XRT 82L24A
consists of four identical transmit and receive channels for E1(2.048 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.
RECEIVER
At the receiver input, cable attenuated AMI signals
can be coupled to the receiver using a capacitor or a
1:2 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 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 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 standard.
GAPPED CLOCK (JA MUST BE ENABLED IN
THE TRANSMIT PATH)
The XRT82L24A LIU is ideal for multiplexer or
mapper applications where the network data crosses
multiple timing domains. As the higher data rates are
de-multiplexed down to T1 or E1 data, stuffing bits
are removed which can leave gaps in the incoming
data stream. If the jitter attenuator is enabled in the
transmit path, the 32-Bit or 64-Bit FIFO is used to
smooth the gapped clock into a steady T1 or E1
output. The maximum gap width of the XRT82L24A
is shown in Table 1.
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 op-
TABLE 1: MAXIMUM GAP WIDTH FOR MULTIPLEXER/MAPPER APPLICATIONS
FIFO DEPTH
MAXIMUM GAP WIDTH
32-Bit
20 UI
64-Bit
50 UI
NOTE: If the LIU is used in a loop timing system, the jitter
attenuator should be enabled in the receive path.
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.
HDB3/AMI 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. Further, any bipolar violation of the HDB3 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
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 E1line signal at RTIP/
RRING drops 16dB (typical) below the 0dB nominal
level the digital circuit is activated to parse through
and check for 32 consecutive zeros before LOS is asserted, to indicate loss of input signal. The number of
10
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XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
consecutive zeros before LOS is declared can be increased to 4096 bits. During extended LOS Mode,
the LOS condition will be cleared when 4096 more
valid data bits are present (when operating in the
Host Mode). The LOS condition is cleared when the
input signal rises above 16dB below 0dB nominal level and meets 12.5% density of 4 ones in a 32 bit window with no more than 16 consecutive zeros.
The Digital LOS Detector will declare an LOS condition, if it detects a string of at least 32 consecutive
"0"s.
The Digital LOS Detector will clear the LOS condition,
if it determines that the incoming E1 line signal has a
pulse density of 12.5% or more without 16 consecutive “0’s” for at least 32 consecutive bit periods.
NOTE: The pulse density requirement of 12.5% accounts
for HDB3 coding.
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.
RECEIVE DATA MUTING
The XRT 82L24A 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 (Register 1, Bit 2 Location) or by
connecting pin 67 High in the Hardware Mode.
Complete Loss of Signal (Zero Amplitude)
If the XRT 82L24A experiences a complete Loss of
Signal (e.g., no signal amplitude), then the XRT
82L24A Clock Recovery PLL enters the Training
Mode, and 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.
Degraded Type of Loss of Signal Event (Non-Zero
Amplitude)
If the XRT 82L24A 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.
LOOP-BACK MODES
Each channel within the XRT 82L24A can be configured to operate in any of the following loop-back
modes:
CONDITIONS FOR DECLARING AND CLEARING
LOS IN THE E1 MODE.
Each E1 channel of the XRT 82L24A has two criteria
for LOS Detection, Analog and Digital. A channel
will declare a LOS condition when both of these LOS
Detectors detect an LOS condition.
Each of these loop-back modes are described in
some detail below.
• Remote Loop-Back Mode
• Digital Local Loop-Back Mode
• Analog Local Loop-Back Mode
REMOTE LOOP-BACK (RLOOP) MODE
With Remote Loop-Back activated, (Channel Control
Register bit 2 = “1”) in Host Mode or in Hardware
Mode with LoopSEL (pin 58) tied Low and LoopEN
tied High received data after the jitter attenuator (if
selected) is looped back to the transmit path using
RxClk as transmit timing. In 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 Loop-Back Mode in Figure 4 &
Figure 5). Remote loop-back has priority over TAOS.
Analog LOS Detector
The Analog LOS Detector will declare an 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.
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.
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
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
11
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
be sent to the line uninterrupted. This loop back feature allows users to configure the line interface as a
pure jitter attenuator. (see Loop-Back Mode in
Figure 6 & Figure 7).
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).
NOTE: Digital Local Loop-Back is not supported in Hardware Mode.
ANALOG LOCAL LOOP-BACK (ALOOP) MODE
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
12
RTIP
Rx
RRing
áç
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
“
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
13
RTIP
Rx
RRing
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
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 XRT 82L24A 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(Register 1, Bit 3 = “1”). In
single rail mode DATAP = “1”, (Register 0, Bit 7 = “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, XRT 82L24A offers several alternative receive
14
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XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
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
RxClk Clock Sampling Edge
Data Sampled
mission to the line using low impedance output drivers.
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”, (Bit 5 = “1”), data is validated on the rising
edge of RxClk and with RClkE=”0”, (Bit 5 = “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 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.
TRANSMIT CLOCK SAMPLING EDGE
NRZ Transmit data at TxPOS/TDATA or TxNEG is
clocked serially into the device using TxClk. With the
interface register bit 4 (TClkE=”1”), input data is sampled on the rising edge of TxClk. The sampling edge
is inverted when TClkE= “0”. In Hardware Mode, the
state of pin 7 (ClkE) controls the sampling edge of
both TxClk and RxClk.
HDB3/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. With register CODES=”1”, AMI
coding is selected. In Hardware Mode, HDB3 or AMI
coding selection is determined by the state of pin 10.
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 trans-
15
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XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
The choice of these codes is made such that an odd
number of “B” pulses is transmitted between consecutive bipolar violation “V” pulses
ated. Driver monitor function 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 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 selects 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.
TxPOS/TDATA and TxNEG Polarity
The intrinsic jitter at the transmit output using a jitterfree input clock source and with the jitter attenuator
disabled will generate no more than 0.03UIpp.
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.
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.
In the Host Mode, when the driver monitor detects no
transitions at TTIP and TRING for more than 128
clock cycles, the DMO bit (bit 7) in the interface register is set and results in an interrupt (INT) to be gener-
INTERFACING THE XRT 82L24A TO THE LINE
The XRT 82L24A in E1 configuration can be transformer coupled to 75Ω coaxial or 120Ω twisted pair
lines as shown in Figure 12 and Figure 13 below.
FIGURE 12. XRT 82L24A CHANNEL 1IN AN E1 UNBALANCED 75 Ω APPLICATION
TxPO S
TxN EG
TxLineC lk
4
3
5
TPO S_0
TTIP_0
R xPO S
R xN EG
R xLineC lk
Loss of signal
99
1
2
BN C
9.1 Ω
1
T1
5
1
C oaxial
C able
TN EG _0
2
TC lk_0
TR ing_0
100
R1
89
R PO S_0
R TIP_0
R2
91
1:2
9.1 Ω
94
8
4
BN C
5
T2
1
1
C oaxial
C able
R N EG _0
R3
18.7 Ω
R C lk_0
R LO S_0
R R ing_0
95
2
8
4
1:2
XR T82L24A
16
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XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
FIGURE 13. XRT 82L24A CHANNEL 1 - E1 120 Ω BALANCED APPLICATION
TxPO S
TxN EG
TxLineC lk
4
3
5
TPO S_0
TTIP_0
9.1 Ω
R xN EG
R xLineC lk
Loss of signal
100
99
1
2
1
T1
5
TN EG _0
TC lk_0
R PO S_0
R TIP_0
R6
91
5
T2
1
R R ing_0
95
4
8
1:2
XR T82L24A
17
R TIP
Twisted
Pair
R4
30.1 Ω
R C lk_0
TR IN G
1:2
9.1 Ω
94
8
4
R N EG _0
R LO S_0
TTIP
Twisted
Pair
TR ing_0
R xPO S
R5
89
R R ing
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
TABLE 2: E1 RECEIVER ELECTRICAL CHARACTERISTICS
(Vdd=3.3V±5%, Ta=-40°C 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
15
20
-
dB
12.5
-
-
% ones
Receiver Sensitivity
11
13
-
dB
With nominal pulse amplitude of 3.0V for
120Ω and 2.37V for 75Ω application.
With -18dB interference signal added.
Interference Margin
-18
-14
-
dB
With 6dB cable loss
Input Impedance
15
-
KΩ
Jitter Tolerance:
20 Hz
700KHz
10KHz---100KHz
10
5
0.3
-
-
UIpp
ITU G.823
-
36
0.5
KHz
dB
ITU G.736
-
10
-
Hz
ITU G.736
14
20
16
-
-
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
18
Cable attenuation @1024KHz
ITU-G.775, ETS1 300 233
áç
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
TABLE 3: E1 TRANSMITTER ELECTRICAL CHARACTERISTICS
(Ta=-40°C to 85°C, Vdd=3.3V±5%, unless otherwise specified)
PARAMETER
MIN
TYP.
MAX
UNIT
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
8
14
10
-
-
dB
dB
dB
Return Loss:
51KHz --- 102KHz
102KHz --- 2048KHz
2048KHz --- 3072KHz
TEST CONDITIONS
Use transformer with 1:2 ratio and 9.1Ω
resistor in series with each end of primary.
Broad Band with jitter free TxClk
applied to the input.
ETSI 300 166
TABLE 4: 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
19
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
FIGURE 14. ITU G.703 E1 PULSE TEMPLATE
TABLE 5: 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
20
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XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
TABLE 6: POWER CONSUMPTION (TA=-40°C TO 85°C, VDD=3.3V + 5%, UNLESS OTHERWISE SPECIFIED.)
PARAMETER
SYMBOL
MIN.
TYP.
MAX.
UNITS
CONDITIONS
Power Consumption
PC
-
450
650
mW
E1(75 Ohm) load. At 50% Mark Density
Power Consumption
PC
-
650
680
mW
E1(75 Ohm) load. At 100% Mark Density
Power Consumption
PC
-
400
500
mW
E1(120 Ohm) load. At 50% Mark Density
Power Consumption
PC
-
540
600
mW
E1(120 Ohm) load. At 100% Mark Density
Power Consumption
PC
-
80
100
mW
All Transmitters Powered-Down
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 7: AC ELECTRICAL CHARACTERISTICS
(Vdd=3.3V±5%, Ta=25°C unless otherwise specified)
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS
-
2.048
-
MHz
MCLK Clock Duty Cycle
40
-
60
%
MCLK Clock Tolerance
-
±50
-
ppm
E1 MCLK Clock Frequency
E1 TxClk Clock Period
TCLKP
-
488
-
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
448
ns
RxClk Fall Time(90%/10%) with 25pF
Loading
RCLKF
Data Pulse Width in Data Slice Mode
RZData
210
21
244
-
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
FIGURE 15. 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 "High" in Command Control Register 0 to select TxCLK inversion.
FIGURE 16. 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 "High"in Command Control Register 0 to select RxCLK inversion.
MICROPROCESSOR INTERFACE
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 8.
XRT 82L24A is equipped with a microprocessor interface for easy device configuration. The parallel port of
the XRT 82L24A is compatible with both Intel and
Motorola address and data buses.
22
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XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
TABLE 8: MICROPROCESSOR INTERFACE SIGNAL
D[7:0]
ADD[3:0]
PTS1
PTS2
Data Input (Output): 8 bits bi-directional data bus for register access.
Address Input: 4 bit address to select internal register location.
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.)
PCLK
Process Clock Input: Input clock for synchronous microprocessor operation. Maximum clock speed is
16MHz. This pin is internally pulled up 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
Chip Select Input: This signal must be low in order to access the parallel port.
RD_DS
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_DTACK 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 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.
23
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
TABLE 9: 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
RZData
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
Channel 0 Register
2
0010
DMO0
LOS0
LCV0
3
0011
Reserved
Reserved
Reserved Reserved
MDMO0
MLOS0
MLCV0
MTCKL0
4
0100
Reserved
Reserved
Reserved ALOOP0
DLOOP0
RLOOP0
TAOS0
TxOFF0
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
DMO1IS
LLOSIS1
LCV1
TCKL1IS
reset=0
TCLK0
reset=0
Channel 1 Register
5
0101
DMO1
LOS1
LCV1
6
0110
Reserved
Reserved
Reserved Reserved
MDMO1
MLOS1
MLCV1
MTCKL1
7
0111
Reserved
Reserved
Reserved ALOOP1
DLOOP1
RLOOP1
TAOS1
TxOFF1
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
DMO2IS
LLOS2IS
LCV2
TCKL2IS
reset=0
TCLK1
reset=0
Channel 2 Register
8
1000
DMO2
LOS2
LVC2
9
1001
Reserved
Reserved
Reserved Reserved
MDMO2
MLOS2
MLCV2
MTCKL2
10
1010
Reserved
Reserved
Reserved ALOOP2
DLOOP2
RLOOP2
TAOS2
TxOFF2
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
DMO3IS
LLOS3IS
LCV3
TCKL3IS
reset=0
TCLK2
reset=0
Channel 3 Register
11
1011
DMO3
LOS3
LCV3
12
1100
Reserved
Reserved
Reserved Reserved
MDMO3
MLOS3
MLCV3
MTCKL3
13
1101
Reserved
Reserved
Reserved ALOOP3
DLOOP3
RLOOP3
TAOS3
TxOFF3
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
reset=0
NOTE: Address 1110 and 1111 R/W Registers (14 and 15)
are Reserved for Exar Testing Purposes
24
TCLK3
reset=0
áç
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
TABLE 10: COMMAND CONTROL REGISTER 0
COMMAND CONTROL REGISTER 0
PARALLEL PORT ADDRESS: 0000
REGISTER
TYPE
RESET
VALUE
R/W
0
BIT NO.
NAME
FUNCTION
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
RZData
RZ Data:
Writing a “1” to this bit selects receive data to pass to the output
after the slicers without re-timing. In this mode, PLL clock recovery, jitter attenuator, decoder and remote loop-back functions are
disabled.
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. 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
NOTE: Register Type Abrbreviation:
R = Read Only, R/W = Read or Write, RUR = Reset Upon Read
25
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
TABLE 11: 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, (approximately 2mS), 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
NOTE: Register Type Abrbreviation:
R = Read Only, R/W = Read or Write, RUR = Reset Upon Read
26
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XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
TABLE 12: 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
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
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.
NOTE: n = channel number 0 to 3.
NOTE: Register Type Abrbreviation:
R = Read Only, R/W = Read or Write, RUR = Reset Upon Read
27
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
TABLE 13: 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.
NOTE: Register Type Abrbreviation:
R = Read Only, R/W = Read or Write, RUR = Reset Upon Read
28
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XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
TABLE 14: 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
7
6
5
****
4
FUNCTION
REGISTER TYPE
RESET VALUE
These bits are Reserved.
R/W
R/W
R/W
0
0
0
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.
NOTE: Register Type Abrbreviation:
R = Read Only, R/W = Read or Write, RUR = Reset Upon Read
29
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
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 17 and Figure 18 is described in
Table 15.
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
FIGURE 17. 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 18. 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
30
áç
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
TABLE 15: 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
31
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
Motorola Interface Timing
family with up to 16.67 MHz clock frequency. The interface timing is shown in Figure 19, Figure 20 and
Figure 21. The I/O specifications are shown in
Table 16.
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
with the timing of a Motorola 68000 microprocessor
FIGURE 19. 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 20. 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
32
áç
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
.
FIGURE 21. MICROPROCESSOR INTERFACE TIMING - RESET PULSE WIDTH
t90
Reset
TABLE 16: MOTOROLA INTERFACE TIMING SPECIFICATION
SYMBOL
PARAMETER
MIN
TYP
MAX
UNITS
Microprocessor Interface - Motorola Read Operations (see Figure 19)
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 20)
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 21)
t90
Reset pulse width
33
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
JITTER TOLERANCE
Input Jitter Tolerance Measurements are presented
for the following two situations.
The results of the Input Jitter Tolerance Measurements are plotted in Figure 22.
1. The Jitter Attenuator within the Channel-UnderTest is disabled.
• Test Pattern 2^15-1
Test Conditions
• (-6dB) Cable Loss
2. The Jitter Attenuator within the Channel-UnderTest is enabled and configured to operate in the Receive Path.
FIGURE 22. RECEIVE MAXIMUM JITTER TOLERANCE
3
10
1000
JAT D isabled
JAT 64bits
JAT 32bits
2
Input Jitter (UIp−p)
10
100
1
10
10
IT U -T G .823 M ask
0
1
10
.1
10
−1
0
10
1
10
2
3
10
10
(Freq.(MHz))
34
4
10
5
10
áç
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
Receiver Jitter Transfer Function (Jitter Attenuator disabled)
Test Conditions:
• Test Pattern 2^15-1
- Input Jitter 0.5UIp-pThe results of the Input Jitter
Tolerance Measurements with the Jitter Attenuator
enabled and configured to operate in the receive path
are plotted in Figure 23.
FIGURE 23. RECEIVER JITTER TRANSFER FUNCTION (JITTER ATTENUATOR DISABLED)
2
G .735-G 739 S pecification
0
−2
20log(Jout/Jin) (dB)
−4
X RT 82L24A
P erform ance
−6
−8
−10
−12
−14
2
3
10
4
10
5
10
10
(Freq.(MHz))
Receiver Jitter Transfer Function (Jitter Attenuator enabled)
Test Conditions:
• Test Pattern 2^15-1
• Input Jitter 75% of Maximum Jitter Tolerance
FIGURE 24. JITTER ATTENUATION FUNCTION
10
0
IT U .G .736 M ask
Jitter Attenuation (dB)
−10
−20
−30
X RT 82L24A P erform ance
−40
−50
−60
0
10
1
10
2
3
10
10
(Freq.(MHz))
35
4
10
5
10
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
áç
REV. 1.1.2
ORDERING INFORMATION
PART NUMBER
PACKAGE
OPERATING TEMPERATURE RANGE
XRT82L24AIV
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°
36
D
áç
XRT82L24A
QUAD E1 LINE TRANSCEIVER WITH CLOCK RECOVERY AND JITTER ATTENUATOR
REV. 1.1.2
REVISION HISTORY
REVISION
DATE
DESCRIPTION
1.0.0
11/02
Initial issue
1.1.0
10/03
Table 8 corrected PCLK frequency from 33MHz to16MHz and changed pulled down to pulled
up. Figures 12 & 13 transformer ratio on Receive side changed from 2:1 to 1:2.
1.1.1
06/04
Added the Manufacturing Mark on the Package Drawing.
1.1.2
07/04
Changed Max power consumption for 100% Mark Density to 680 and 600 mW respectively for
75 and 120 Ohm Loads.
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 2004 EXAR Corporation
Datasheet August 2004.
Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited.
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