Download Ethernet Protection

Broadband Protection
Outline
Broadband Application Overview
Secondary Protection Issues





Broadband: ADSL / VDSL Data Rates
CPE Primary / Secondary / Tertiary
– GDT or P3002G / Fuse Solution

CO Primary / Secondary / Tertiary
– xDSL over POTS Interface
Basic CO Secondary Protection Circuits





HV Solutions
HV GDT & Fuse Solutions
T&R SIDACtor / TeleLink Solutions
Y SIDACtor / TeleLink Solutions
SDP / Enhanced TeleLink Solutions


HV Solutions / Stress Points
Longitudinal Conversion
AC Power Cross
– TeleLink / Enhanced
Capacitance
Capacitance Linearity
Summary Selection Chart
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Telecom Overview
Remote
Terminal (RT)
Satellite-Based
Video Content
(CBS, HBO, etc.)
CPE
Internet
Service
Network
CPE
Central Office
(CO)
Satellite
Base Station
Public Switched
Telephone
Network (PSTN)
CPE
Central Office
(CO)
Central Office
(CO)
CPE
Cable Head End
Cell Phone
Base Station
Remote
Terminal (RT)
Remote
Terminal
(RT)
CPE
CPE
CATV Line
Amp & Distrib
CPE
CPE
CPE
Remote
Terminal (RT)
CPE
CATV Line
Amp & Distrib
Satellite
Base Station
CPE
CPE
Broadband Overview
• Broadband encompasses many technologies and protocols.
• For this module we will be focusing on the xDSL technololgies.
• xDSL uses complex coding schemes to pack more data into less
bandwidth.
POTS
POTS
ADSL
T1
T1
E1
E1
ADSL2+
ADSL2+
ADSL2++
ADSL2++
10BaseT
10BaseT
VDSL
VDSL
VDSL2
VDSL2
T3
T3
100BaseT
100BaseT
0
20
40
60 Mhz 80
Data Rates
ADSL
Spectra
100
120
140
0
50
100
150
200
Mbps/Pair
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Customer End (CPE)
Primary / Secondary / Tertiary Protection
Protection is a coordinated layering of protection technologies
Outdoor
Cabling
Primary
Protection
Secondary
Protection
• OVP ~ 1000V
• Thermal Overload
• UL
• NEBS
• GR-974
• OVP ~ 300V
• OCP ~ Fuse / PTC
• GR-1089
• UL 60950
• ITU K.20 / K.21
NID or
Building Entrance
Tertiary
Protection
• OVP ~ 30V
• No Regulatory Need
Line Card
• Primary Protection is usually provided by GDT’s used in 5-Pin Modules, NID’s or BEP’s.
• Tertiary Protection is covered in the Tertiary Protection Module
• In North America, the more stringent CO End requirements may apply to equipment at the
customer’s site if the equipment is owned or installed by the service provider.
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Customer End (CPE)
Secondary Protection




CPE Fuse Selection
Compliance w/ ITU K.21, TIA 968-A
and GR-1089 Intra-building.
Worst Case: Must not open on a
100A 5x310 lightning surge.
The I2T of this surge is 2.21 A2S
Suggested Fuses:
–
–
–
–
–
–
SL0902A350
SL1011A350
229.75P 2AG Slow Cartridge
230001P 2AG Slow Pigtail
224003P 2AG Fast Cartridge
2321.25XP 5x20 Med Pigtail
3721100 TR5 Slow
4651.25 6mm Slow Nano
P3002SB
P3002G
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Central Office (CO) End
Primary / Secondary / Tertiary Protection
Protection is a coordinated layering of protection technologies
Outdoor
Cabling
Primary
Protection
Secondary
Protection
• OVP ~ 1000V
• Thermal Overload
• UL
• NEBS
• GR-974
• OVP ~ 300V
• OCP ~ Fuse / PTC
• GR-1089
• UL 60950
• ITU K.20 / K.21
Main Dist. Frame
Tertiary
Protection
• OVP ~ 30V
• No Regulatory Need
Line Card
• CO End may refer to the Central Office or RT’s (Remote Terminals).
• Primary Protection is usually provided in the Main Distributing Frame by 5-Pin
Modules or other modular protectors.
• Tertiary Protection is covered in the Tertiary Protection Module.
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xDSL Interface Overview
SLIC
A
Splitter
C
Tertiary Protection
DSL Line
Driver
A.
B.
C.
D.
E.
F.
SLIC
Protection
B
Secondar
y
Protection
SLIC Circuit
Splitter
DSL Line Driver
Coupling Transformer
DC Blocking Capacitor
Telephone Line
Primary
Protection
F
E
D
Splitter blocks high frequency DSL noise from
interfering with voice circuits.
See these modules for more information
• SLIC Protection Module
• Tertiary Protection Module
Coupling Transformer blocks HV from damaging
DSL Line Driver.
DC Blocking Capacitor keeps transformer from
shorting out phone line.
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Outline
Broadband Application Overview
Secondary Protection Issues





Broadband: ADSL / VDSL Data Rates
CPE Primary / Secondary / Tertiary
– GDT or P3002G / Fuse Solution

CO Primary / Secondary / Tertiary
– xDSL over POTS Interface
Basic CO Secondary Protection Circuits





HV Solutions
HV GDT & Fuse Solutions
T&R SIDACtor / TeleLink Solutions
Y SIDACtor / TeleLink Solutions
SDP / Enhanced TeleLink Solutions


HV Solutions / Stress Points
Longitudinal Conversion
AC Power Cross
– TeleLink / Enhanced
Capacitance
Capacitance Linearity
Summary Selection Chart
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High Voltage Capacitor Solution
HV
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GDT / TeleLink Fuse Solution
If GDT is HV, Fuses
are not used.
F1
F2
GDT: SL1003A350
Fuse: TeleLink 04611.25ER
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Standard SIDACtor / TeleLink Solution
SIDACtor: P3500SCMC
Fuse: TeleLink 04611.25ER
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“Y” SIDACtor / TeleLink Solution
SIDACtor: P3403ACMC
Fuse: TeleLink 04611.25ER
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SDP / Enhanced TeleLink Solution
SIDACtor: SDP3500Q38CB
Fuse: Enhanced TeleLink 04611.25EER
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Outline
Broadband Application Overview
Secondary Protection Issues





Broadband: ADSL / VDSL Data Rates
CPE Primary / Secondary / Tertiary
– GDT or P3002G / Fuse Solution

CO Primary / Secondary / Tertiary
– xDSL over POTS Interface
Basic CO Secondary Protection Circuits





HV Solutions
HV GDT & Fuse Solutions
T&R SIDACtor / TeleLink Solutions
Y SIDACtor / TeleLink Solutions
SDP / Enhanced TeleLink Solutions


HV Solutions / Stress Points
Longitudinal Conversion
AC Power Cross
– TeleLink / Enhanced
Capacitance
Capacitance Linearity
Summary Selection Chart
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Surge Voltage Let-Through
Splitter
DSL
Chipset
D
E
F
A
C
B
Surge Voltage Let-Through Threatens:
A.
Capacitor (differential surge tests) – HV Caps are bigger and more expensive.
B.
Transformer insulation – HV transformers are bigger and more expensive.
C.
Driver IC’s – Higher performance drivers may be more susceptible.
D.
LP Filter – Higher voltage components are bigger and more expensive.
E.
PCB traces – Must be spaced further apart, using up valuable board space.
F.
Backplane connectors – More robust connectors will cost more.
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Transformer Coupled Applications
No Conversion of Common-Mode Events to Differential Mode
300V
R
DSL Chipset
2-Element Solution
310V
R
150V
OVP Switches Close
when VBO is present.
R
3-Element Solution
DSL Chipset
150V
160V
R
R
SDP/ SEP Solution
DSL Chipset
300V
R
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AC Power Cross Testing
 Intended to simulate accidental contact of telephone wires
with power cables.
 Requirements around the globe vary widely.
 Most Stringent: GR-1089
– 600 VRMS @ 2.2 Amps for 15 Minutes Minimum
 Passing Criteria varies as well
– Some require equipment to remain operational
– Some only require fire prevention
 PTC’s may be used, but their resistance will cause signal
issues with higher bandwidth signals, such as VDSL.
 GDT’s have a higher on-state voltage which can cause
heating problems during AC Power Cross events.
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VDSL Overcurrent Protection
 Only Littelfuse offers an Enhanced TeleLink® Fuse
to assure compliance with power cross test
requirements!
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Low Capacitance


High Capacitance will rob power
from the signal.
Capacitance gains in
importance as the data rate of
the signal increases.
– Non-Issue for Voice, T1/E1
– Minor Issue for T3, ADSL
– Major Issue for VDSL, Ethernet

Only GDT & SDP devices
have capacitance values that
are low enough to preserve
signal power on VDSL lines.
Typical Capacitance Values
(Zero Line Voltage)
SDPxxx0Q38CB
VBIAS = 50V
11 pF
SDPxxx0Q38B
23 pF
P0080SCMC
73 pF
P3100SCMC
50 pF
P1553ACMC
28 pF
P3203ACMC
25 pF
GDT
<1 pF
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Constant Capacitance / Changing Voltage





Error-Free Broadband Requires Unchanging Capacitance As Line
Voltage Varies
Changing Capacitance Causes Data Errors
Constant Capacitance Becomes More Critical as Data Rates
Increase
Only the Patented Circuit of the SDP / SEP Can Offer Constant
Capacitance in a Semiconductor Protector
Because they are not semiconductor devices, GDT’s have none of
these issues.
SIDACtor Capacitance vs Line Voltage
100
90
P0080SAMC
P0300SAMC
70
P0300SCMC
P0640SCMC
pF
60
P2600SCMC
P3100SCMC
50
P3100D
40
P3500SCMC
30
20
10
Increasing Bias Voltage
P0080SCMC
80
0
0.1
1
Line Voltage
10
100
Ideal Constant
Capacitance
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Outline
Broadband Application Overview
Secondary Protection Issues





Broadband: ADSL / VDSL Data Rates
CPE Primary / Secondary / Tertiary
– GDT or P3002G / Fuse Solution

CO Primary / Secondary / Tertiary
– xDSL over POTS Interface
Basic CO Secondary Protection Circuits





HV Solutions
HV GDT & Fuse Solutions
T&R SIDACtor / TeleLink Solutions
Y SIDACtor / TeleLink Solutions
SDP / Enhanced TeleLink Solutions


HV Solutions / Stress Points
Longitudinal Conversion
AC Power Cross
– TeleLink / Enhanced
Capacitance
Capacitance Linearity
Summary Selection Chart
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Solution Comparison Chart
Regulatory Test Performance
Secondary Protection
Scheme
↓
DSL Performance
Board
Space
Required
Surge Voltage
Let-Through
Common-Mode
Surge
Conversion
AC Power
Cross
Survival
Capacitance
Cap
Voltage
Linearity
HV Cap
Good
Good
Good
Excellent
Excellent
Fair
HV Cap + HV GDT
Good
Good
Good
Excellent
Excellent
Poor
GDT + Fuses
Good
Good
Fair
Excellent
Excellent
Fair
SIDACtor + Fuses
Excellent
Poor
Excellent
Poor
Poor
Good
“Y” SIDACtor + Fuses
Excellent
Good
Excellent
Fair
Fair
Good
SDP + Fuses
Excellent
Excellent
Excellent
Excellent
Excellent
Excellent
This table assumes that quality tertiary protection is in place!
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Thank You!
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