XRT5897
Seven-Channel E1
Line Interface
December 2001-3
FEATURES
D Compliant with ITU G.703 Pulse Mask Template for
2.048Mbps (E1) Rates
D Compliant with ITU--T G.823 Jitter Tolerance Requirements
D Seven Independent CEPT Transceivers
D Logical Inputs Accept either 3.3V or 5.0V Levels
D Supports Differential Transformer Coupled
Receivers and Transmitters
D Ultra-Low Power Dissipation
D +3.3V Supply Operation
D On Chip Pulse Shaping for Both 75W and 120W Line
Drivers
D Individual Transmit Channel Over Temperature
Protection
D Compliant with ITU G.775 LOS Declaration/Clearing
Recommendation
APPLICATIONS
D Optional User Selectable LOS Declaration/Clearing
Delay
D SDH Multiplexer
D Digital Cross Connects
GENERAL DESCRIPTION
The XRT5897 is an optimized seven channel 3.3V line
interface unit fabricated using low power CMOS
technology. The device contains seven independent E1
channels. It is primarily targeted toward SDH multiplexers
that accommodate TU12 Tributary Unit Frames. Line
cards in these units multiplex 21 E1 interfaces into higher
SDH rates. Devices with seven E1 interfaces such as the
XRT5897 provide the most efficient method of
implementing 21 channel line cards. Each channel
performs the driver and receiver functions necessary to
convert bipolar signals to logical levels and vice versa.
The device requires transformers on both receiver and
transmitter sides, and supports both balanced and
unbalanced interfaces.
The device offers two distinct modes of LOS detection.
The first method, which does not require an external
clock, provides an LOS output indication signal with
thresholds and delay that comply with the ITU G.775
requirements. In the second mode, the user provides an
external clock that increases the delay for LOS
declaration and clearing. This feature provides the user
with the flexibility to implement LOS specifications that
require a delay greater than the G.775 requirements.
ORDERING INFORMATION
Part No.
Package
Operating
Temperature Range
XRT5897IV
100 Lead TQFP (14 x 14 x 1.4mm)
-40°C to +75°C
Rev. 1.11
E2001
EXAR Corporation, 48720 Kato Road, Fremont, CA 94538 z (510) 668-7000 z FAX (510) 668-7017
XRT5897
BLOCK DIAGRAM
Tranceiver 1
Tranceiver 2
Tranceiver 3
Tranceiver 4
Tranceiver 5
Tranceiver 6
Tranceiver 7
RTIP7 (69)
TIP
RX INPUT
RING
1:2
RXPOS7 (5)
R1
R2
Singnal
Peak
Detector
Receive
Comparators
RXNEG7 (6)
RRING7 (68)
VCC
LOS
Detect
LOSCNT (73)
LOSSEL (38)
Transmit
Line
Drivers
TIP
TX OUTPUT
RING
2:1
R3
TTIP7 (89)
9.1
R4
TRING7 (91)
0
0
Pulse
Shaping
1
MUX
O
Loss
Delay
Counter
MUX
NRZ
To
RZ
Duty
Cycle
Adjust
LOS7 (4)
TXCLK7 (87)
TXPOS7 (85)
TXNEG7 (86)
1
1
9.1
Figure 1. XRT5897 Block Diagram
Receiver Notes
D The same type 1:2CT ratio transformer may be
used at the receiver input and transmitter output.
D LOSCNT (pin 73) is unconnected when LOSSEL is
logic 1, or connected to an external clock when
LOSSEL is logic 0.
D R1 and R2 are both 150W for 75W operation, or
240W for 120W operation.
Transmitter Notes
D Return loss exceeds ITU G.703 specification with
these resistors and a 1:2CT ratio input transformer.
D Return loss exceeds ETSI 300 166 specification
with a 1:2 ratio transformer.
LOS (Loss of Signal) Notes
D R3 and R4 are always 9.1W for both 75W and 120W
applications.
D An approach exists that permits the user to operate
the XRT5897 with a 5V power supply. For more
information, please see application note TAN-12.
D LOSSEL (pin 38) is connected to logic “1” for ITU
G.775 compliant LOS delay, or to logic 0 for user
programmable additional delay.
Rev. 1.11
2
XRT5897
RXPOS6
RXNEG6
LOSCNT
GND
RTIP6
RRING6
RTIP7
RRING7
VCC
GND
VCC
RRING5
RTIP5
GND
TTIP5
V CC
TRING5
GND
TRING4
V CC
TTIP4
GND
RTIP4
RRING4
TXCLK4
PIN CONFIGURATION
51
75
50
76
100
1
25
RXPOS1
RXNEG1
VCC
LOS7
RXPOS7
RXNEG7
RTIP1
RRING1
VCC
GND
VCC
RRING2
RTIP2
GND
TTIP2
VCC
TRING2
GND
TRING3
VCC
TTIP3
GND
RTIP3
RRING3
TXCLK3
LOS6
TXPOS6
TXNEG6
TXCLK6
GND
TTIP6
VCC
TRING6
GND
TXPOS7
TXNEG7
TXCLK7
GND
TTIP7
VCC
TRING7
GND
TRING1
VCC
TTIP1
GND
TXCLK1
TXNEG1
TXPOS1
LOS1
100 LEAD THIN QUAD FLAT PACK
(14 x 14 x 1.4 mm, TQFP)
Rev. 1.11
3
26
TXNEG4
TXPOS4
LOS4
RXPOS4
RXNEG4
TXPOS5
TXNEG5
TXCLK5
RXNEG5
RXPOS5
LOS5
GND
LOSSEL
VCC
LOS2
RXPOS2
RXNEG2
TXCLK2
TXNEG2
TXPOS2
RXNEG3
RXPOS3
LOS3
TXPOS3
TXNEG3
XRT5897
PIN DESCRIPTION
Pin #
Symbol
Type
Description
1
RXPOS1
O
Receiver 1 Positive Data Out. Positive RZ data output for channel 1.
2
RXNEG1
O
Receiver 1 Negative Data Out. Negative RZ data output for channel 1.
3
VCC
4
LOS7
O
Receiver 7 Loss of Signal. Asserted during LOS condition.
5
RXPOS7
O
Receiver 7 positive Data Out. Positive RZ data output for channel 7.
6
RXNEG7
O
Receiver 7 Negative Data Out. Negative RZ data output for channel 7.
7
RTIP1
I
Receiver 1 Positive Bipolar Input.
8
RRING1
I
Receiver 1 Negative Bipolar Input.
9
VCC
Positive Supply (+3.3V + 5%). Analog circuitry.
10
GND
Analog Ground.
11
VCC
Positive Supply (+3.3V + 5%). Receivers 1, 2, 3, and 7.
12
RRING2
I
Receiver 2 Negative Bipolar Input.
13
RTIP2
I
Receiver 2 Positive Bipolar Input.
Positive Supply (+3.3V + 5%). Digital circuitry.
14
GND
15
TTIP2
Analog Ground. Receivers 1, 2, 3, and 7.
16
VCC
17
TRING2
18
GND
19
TRING3
20
VCC
21
TTIP3
22
GND
23
RTIP3
I
Receiver 3 Positive Bipolar Input.
24
RRING3
I
Receiver 3 Negative Bipolar Input.
25
TXCLK3
I
Transmitter 3 Clock Input. Use for clocked mode with NRZ data.1
26
TXNEG3
I
Transmitter 3 Negative Data Input. Negative NRZ or RZ data input.1
27
TXPOS3
I
Transmitter 3 Positive Data Input. Positive NRZ or RZ data input.1
28
LOS3
O
Receiver 3 Loss of Signal. Asserted during LOS condition.
29
RXPOS3
O
Receiver 3 Positive Data Out. Positive RZ data output for channel 3.
30
RXNEG3
O
Receiver 3 Negative Data Out. Negative RZ data output for channel 3.
31
TXPOS2
I
Transmitter 2 Positive Data Input. Positive NRZ or RZ data input.1
32
TXNEG2
I
Transmitter 2 Negative Data Input. Negative NRZ or RZ data input.1
33
TXCLK2
I
Transmitter 2 Clock Input. Use for clocked mode with NRZ data.1
34
RXNEG2
O
Receiver 2 Negative Data Out. Negative RZ data output for channel 2.
35
RXPOS2
O
Receiver 2 Positive Data Out. Positive RZ data output for channel 2.
O
Transmitter 2 Positive Bipolar Output.
Positive Supply (+3.3V + 5%). Transmitter channel 2.
O
Transmitter 2 Negative Bipolar Output.
Digital Ground. Transmitter channel 2.
O
Transmitter 3 Negative Bipolar Output.
Positive Supply (+3.3V + 5%). Transmitter channel 3.
O
Transmitter 3 Positive Bipolar Output.
Digital Ground. Transmitter channel 3.
Note:
1 Has internal pull-up 50KW resistor.
Rev. 1.11
4
XRT5897
PIN DESCRIPTION (CONT’D)
Pin #
Symbol
Type
36
LOS2
O
Description
Receiver 2 Loss of Signal. Asserted during LOS condition.
37
VCC
38
LOSSEL
39
GND
40
LOS5
O
Receiver 5 Loss of Signal. Asserted during LOS condition.
41
RXPOS5
O
Receiver 5 Positive Data Out. Positive RZ data output for channel 5.
42
RXNEG5
O
Receiver 5 Negative Data Out. Negative RZ data output for channel 5.
43
TXCLK5
I
Transmitter 5 Clock Input. Use for clocked mode with NRZ data.1
44
TXNEG5
I
Transmitter 5 Negative Data Input. Negative NRZ or RZ data input.1
45
TXPOS5
I
Transmitter 5 Positive Data Input. Positive NRZ or RZ data input.1
46
RXNEG4
O
Receiver 4 Negative Data Out. Negative RZ data output for channel 4.
47
RXPOS4
O
Receiver 4 Positive Data Out. Positive RZ data output for channel 4.
48
LOS4
O
Receiver 4 Loss of Signal. Asserted during LOS condition.
49
TXPOS4
I
Transmitter 4 Positive Data Input. Positive NRZ or RZ data input.1
50
TXNEG4
I
Transmitter 4 Negative Data Input. Negative NRZ or RZ data input.1
51
TXCLK4
I
Transmitter 4 Clock Input. Use for clocked mode with NRZ data.1
52
RRING4
I
Receiver 4 Negative Bipolar Input.
53
RTIP4
I
Receiver 4 Positive Bipolar Input.
54
GND
55
TTIP4
56
VCC
57
TRING4
58
GND
59
TRING5
60
VCC
61
TTIP5
Digital Supply (+3.3V + 5%). Digital circuitry.
I
Loss of Signal Delay Select. “Hi” selects G.775, “Lo” selects user programmable.1
Digital Ground.
Analog Ground.
O
Transmitter 4 Positive Bipolar Output.
Positive Supply (+3.3V + 5%). Transmitter channel 4.
O
Transmitter 4 Negative Bipolar Output.
Digital Ground. Transmitter channel 4.
O
Transmitter 5 Negative Bipolar Output.
Positive Supply (+3.3V + 5%). Transmitter channel 5.
O
Transmitter 5 Positive Bipolar Output.
62
GND
63
RTIP5
I
Digital Ground. Transmitter channel 5.
Receiver 5 Positive Bipolar Input.
64
RRING5
I
Receiver 5 Negative Bipolar Input.
65
VCC
Positive Supply (+3.3V + 5%). Low level transmitter analog circuitry.
66
GND
Analog Ground. Low level transmitter analog circuitry.
67
VCC
Positive Supply (+3.3V + 5%). Receiver channels 4, 5, and 6.
68
RRING7
I
Receiver 7 Negative Bipolar Input.
69
RTIP7
I
Receiver 7 Positive Bipolar Input.
70
RRING6
I
Receiver 6 Negative Bipolar Input.
Note:
1 Has internal pull-up 50KW resistor.
Rev. 1.11
5
XRT5897
PIN DESCRIPTION (CONT’D)
Pin #
Symbol
Type
Description
71
RTIP6
I
72
GND
73
LOSCNT
I
Loss of Signal Timing Clock Input. For user-programmable LOS delay.1
74
RXNEG6
O
Receiver 6 Negative Data Out. Negative RZ data output for channel 6.
75
RXPOS6
O
Receiver 6 Positive Data Out. Positive RZ data output for channel 6.
76
LOS6
O
Receiver 6 Loss of Signal. Asserted during LOS condition.
77
TXPOS6
I
Transmitter 6 Positive Data Input. Positive NRZ or RZ data input.1
78
TXNEG6
I
Transmitter 6 Negative Data Input. Negative NRZ or RZ data input.1
79
TXCLK6
I
Transmitter 6 Clock Input. Use for clocked mode with NRZ data.1
80
GND
81
TTIP6
Receiver 6 Positive Bipolar Input.
Analog Ground. Receiver channels 4, 5, and 6.
Digital Ground. Transmitter channel 6.
O
Transmitter 6 Positive Bipolar Output.
82
VCC
83
TRING6
Positive Supply (+3.3V + 5%). Transmitter channel 6.
84
GND
85
TXPOS7
I
Transmitter 7 Positive Data Input. Positive NRZ or RZ data input.1
86
TXNEG7
I
Transmitter 7 Negative Data Input. Negative NRZ or RZ data input.1
87
TXCLK7
I
Transmitter 7 Clock Input. Use for clocked mode with NRZ data.1
O
Transmitter 6 Negative Bipolar Output.
Digital Ground.
88
GND
89
TTIP7
90
VCC
91
TRING7
92
GND
93
TRING1
94
VCC
95
TTIP1
96
GND
97
TXCLK1
I
Transmitter 1 Clock Input. Use for clocked mode with NRZ data.1
98
TXNEG1
I
Transmitter 1 Negative Data Input. Negative NRZ or RZ data input.1
99
TXPOS1
I
Transmitter 1 Positive Data Input. Positive NRZ or RZ data input.1
100
LOS1
O
Receiver 1 Loss of Signal. Asserted during LOS condition.
Analog Ground.
O
Transmitter 7 Positive Bipolar Output.
Positive Supply (+3.3V + 5%). Transmitter channel 7.
O
Transmitter 7 Negative Bipolar Output.
Digital Ground. Transmitter channel 7.
O
Transmitter 1 Negative Bipolar Output.
Positive Supply (+3.3V + 5%). Transmitter channel 1.
O
Transmitter 1 Positive Bipolar Output.
Digital Ground. Transmitter channel 1.
Note:
1 Has internal pull-up 50KW resistor.
Rev. 1.11
6
XRT5897
ELECTRICAL CHARACTERISTICS
Test Conditions: VCC = 3.3V + 5%, TA = -40 to 25 to 75°C, Unless Otherwise Specified
Symbol
Parameter
Min.
Typ.
Max.
Unit
Voltage Supply
3.135
3.3
3.465
V
VIH
Input High Level
2.0
5.0
V
VIL
Input Low Level
0.8
V
Conditions
DC Electrical Characteristics
Parameters
VCC
3.3V operation
Inputs
Outputs
VOH
Output High Level
VOL
Output Low Level
2.4
V
IOH = -4mA
0.4
V
IOL = 4mA
12
dB
Cable loss at 1.024MHz (Relative
to 0dB = 2.37Vp measured from
RTIP or RRING to ground).
dB
With 6dB cable loss
%
% of peak input voltage at -3dB
cable loss
Receiver Specifications
RXCL
Allowable Cable Loss
0
RXIM
Interference Margin
-15
-12
RXXI
Receiver Slicing Threshold
45
50
55
RXLOSSET
LOS Must Be Set If RX Sig.
Atten. ² 32dB (For Any Valid
Data Pattern)
15
dB
Relative to 0dB = 2.37Vp
Measured from RTIP or RRING to
ground.
RXLOSCLR
LOS Must Be Cleared If RX Sig.
Atten. < 9dB
13
dB
Relative to 0dB = 2.37Vp
measured from RTIP or RRING to
ground.
RXLOSHYST
Hysteresis on Input Data
2
dB
For LOS output state change
5
kW
Up to 3.072MHz (Measured from
RTIP or RRING to ground).
20Hz
10
UIpp
700Hz
5
UIpp
0.3
UIpp
51khz -- 102kHz
14
dB
102kHz -- 2048kHz
20
dB
2048kHz -- 3072kHz
16
dB
RXIN
Input Impedance
Jitter Tolerance:
10kHz -- 100kHz
Return Loss:
Per ITU--T G.703
Power Specifications VCC = 3.3V
PD
Power Dissipation
715
920
mW
All 1’s Transmit and Receive 75W
PD
Power Dissipation
117
155
mW
All Drivers Power Down
PC
Power Consumption 75W
1260
1465
mW
All 1’s Transmit and Receive
PC
Power Consumption 75W
880
1065
mW
50% data density, Transmit and Receive
Rev. 1.11
7
XRT5897
PC
Power Consumption 120W
1025
1255
mW
All 1’s Transmit and Receive
PC
Power Consumption 120W
745
945
mW
50% data density, Transmit and Receive
Note:
Bold face parameters are covered by production test and guaranteed over operating temperature range.
Rev. 1.11
8
XRT5897
ELECTRICAL CHARACTERISTICS (CONT’D)
Test Conditions: VCC = 3.3V + 5%, TA = -40 to 25 to 75°C, Unless Otherwise Specified
Symbol
Parameter
Min.
Typ.
Max.
Unit
Conditions
AC Electrical Characteristics
VTXOUT
Output Pulse Amplitude
(RL = 75W)
2.13
2.37
2.60
V
Trans. = 1:2 ratio, 9.1W in series
with each end of primary
VTXOUT
Output Pulse Amplitude
(RL = 120W)
2.70
3.0
3.30
V
Trans. = 1:2 ratio, 9.1W in series
with each end of primary
TXPW
Output Pulse Width
224
244
264
ns
PNIMP
Pos/Neg Pulse Unbalanced
5
%
488
ns
T1
TXCLK Clock Period (E1)
T2
TXCLK Duty Cycle
30
TSU
Data Set-up Time, TDATA to
TXCLK
75
ns
50% TXCLK Duty Cycle
THO
Data Hold Time, TDATA to
TXCLK
30
ns
50% TXCLK Duty Cycle
50
70
%
TR
TXCLK Rise Time (10% to 90%)
40
ns
TF
TXCLK Fall Time (10% to 90%)
40
ns
Data Prop. Delay No-Clock
Mode
35
Data Prop. Delay Clock Mode
470
T3-noclk
T3-clk
ns
ns
50% TXCLK Duty Cycle
T4
Receive Data High
269
ns
0dB Cable Loss
T5
RX Data Prop. Delay
40
ns
15pF Load
T6
Receive Rise Time
40
ns
15pF Load
T7
Receive Rise Time
40
ns
15pF Load
219
244
50
Note:
Bold face parameters are covered by production test and guaranteed over operating temperature range.
ABSOLUTE MAXIMUM RATINGS
Storage Temperature . . . . . . . . . . . . -65°C to +150°C
Operating Temperature . . . . . . . . . . -40°C to +75°C
Supply Voltage . . . . . . . . . . . . . . . . . . +0.3V to +6.0V
Rev. 1.11
9
XRT5897
Disabling Output Drivers
Output drivers may be individually disabled (hi-z output) by either of the following methods.
1. Either connect the transmit data inputs TXPOS
and TXNEG for the channel to be disabled to a logic 1 source (VCC), or allow them to float (inputs
have internal pull--up resistors).
2. Connect TXCLK for the channel to be disabled to
logic 0 source (Ground), and also apply data to the
TXPOS and TXNEG inputs of that channel.
TRANSFORMER REQUIREMENTS
Turns Ratio
Line Impedance
Turns Ratio
Line Impedance
1:2 CT
75W or 120W
1:2
75W or 120W
Table 1. Input Transformer Requirements
Table 2. Output Transformer Requirements
Note:
The same type 1:2 CT ratio device may be used at both receiver input and transmitter output.
The following transformers have been tested with the XRT5897:
HALO type TG26-1205(package contains two 1 CT:2 CT ratio transformers)
Pulse type PE-65535 (1:2 CT ratio)
Transpower Technologies type TTI 7154-R (1:2 CT ratio)
Magnetic Supplier Information:
HALO Electronics, Inc.
P.O. Box 5826
Redwood City, CA 94063
Tel. (415) 568-5800
Fax. (415)568-6161
Pulse
Telecom Product Group
P.O. Box 12235
San Diego, CA 92112
Tel. (619) 674-8100
Fax. (619) 674-8262
Transpower Technologies, Inc.
24 Highway 28, Suite 202
Crystal Bay, NV 89402--0187
Tel. (702) 831--0140
Fax. (702) 831--3521
Rev. 1.11
10
XRT5897
TSU
THO
TXPOS (n)
TSU
TXNEG (n)
T2
T1
TR
TXCLK (n)
THO
TF
TXPW
T3
T3
VTXOUT
TXOUT (n)
VTXOUT
TXPW
Figure 2. Transmit Timing Diagram
RXIN (n)
T5
T4
T6
T7
RPOS (n)
T5
T4
RXNEG (n)
Figure 3. Receive Timing Diagram
Rev. 1.11
11
T6
T7
XRT5897
RETURN LOSS SPECIFICATIONS
The following transmitter and receiver return loss specifications are based on a typical 1:2CT ratio transformer.
75W
120W
Frequency Range
Min.
Typ.
Min.
Typ.
Unit
51kHz to 102kHz
16
22
10
15
dB
102kHz to 2.048MHz
16
22
10
15
dB
2.048MHz to 3.072MHz
11
18
10
14
dB
Table 3. Transmitter Return Loss Specification
Transmit Return Loss Notes
D Output transformer ratio is 1:2 (return loss exceeds
ETSI 300 166 with this transformer).
D For both 75W and 120W applications, 9.1W, 1% resistors are connected between each end of the
transformer primary and the XRT5897 TTIP and
TRING pins.
75W
120W
Frequency Range
Min.
Typ.
Min.
Typ.
Unit
51kHz to 102kHz
16
28
15
18
dB
102kHz to 2.048MHz
22
34
22
25
dB
2.048MHz to 3.072MHz
18
26
20
30
dB
Table 4. Receiver Return Loss Specification
Receiver Return Loss Notes
D Input transformer ratio is 1:2 CT.
D Each half of transformer secondary is terminated
with 150W for 75W operation, or 240W for 120W operation (resistors are 1% tolerance).
D Transformer center tap is grounded.
Rev. 1.11
12
XRT5897
SYSTEM DESCRIPTION
This device is a seven channel E1 transceiver that
provides an electrical interface for 2.048Mbps
applications. Its unique architecture includes seven
receiver circuits that convert ITU G.703 compliant bipolar
signals to TTL compatible logic levels. Each receiver
includes a LOS (Loss of Signal) detection circuit that may
be configured for either a fixed or a user-programmable
LOS response time delay. Similarly, in the transmit
direction, seven transmitters convert TTL compatible
logic levels to G.703 compatible bipolar signals. Each
transmitter may be operated either with RZ, or NRZ data
types. In NRZ mode a transmit clock is required as well.
The following description applies to any of the seven
receivers or transmitters contained in the XRT5897.
Therefore, the suffix numbers for a particular channel are
deleted for simplicity. i.e. “RTIP” applies to RTIP1 through
RTIP7.
compliance with ITU G.775 specification. When LOSSEL
is connected to logic “0”, the user-programmable delay
mode is enabled. In this mode the user has the option of
extending the delay of LOS declaration and clearing
specified in the ITU G.775. This is done by providing a
user-supplied clock to LOSCNT (pin 73). The “user
programmable mode” is provisioned to allow systems
designers to comply with older versions of LOS
specifications in legacy systems. It needs to be stressed
that the delay for declaration and clearing of the LOS
condition will never be less than the range specified in the
G.775 specification (10-255 pulse intervals).
The LOS detection/clearing circuitry of the XRT5897 in
“automatic” mode will detect LOS when the incoming
signal has “no transitions,” i.e. when the signal level is less
than or equal to a signal level AD dB below nominal signal
level, for N consecutive pulse intervals, where 10