SEMTECH LC04-12

LC04-12
Dual Low Capacitance TVS Array
for Telecom Line-Card Applications
PROTECTION PRODUCTS
Description
Features
u Transient protection for high-speed data lines to
The LC04-12 has been specifically designed to protect
sensitive components which are connected to highspeed telecommunications lines from over voltages
caused by lightning, ESD (electrostatic discharge), and
EFT (electrical fast transients).
The device is in a JEDEC SO-16 NB package. It is
designed to provide metallic (Tip to Ring) or common
mode (Tip to Ground & Ring to Ground) surge protection for up to two Tip and Ring pairs. The low capacitance topology means signal integrity is preserved on
high-speed lines. The high surge capability (600W,
tp=10/1000µs) makes the LC04-12 suitable for
telecommunications systems operating in harsh transient environments. The LC04-12 is designed to meet
the lightning surge requirements of Bellcore GR1089(intra-building), ITU K.20, and IEC 61000-4-5.
The features of the LC04-12 are ideal for protecting
ADSL, RS-232, RS-423, RS-422, and V.90 interfaces.
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Bellcore GR 1089 IPP=100A (2/10µs)
ITU K.20 IPP=100A (5/310µs)
IEC 61000-4-2 (ESD) 15kV (air), 8kV (contact)
IEC 61000-4-5 (Lightning) IPP=100A (8/20µs)
Protects two tip and ring line pairs
Low capacitance for high-speed interfaces
High surge capability
Low clamping voltage
Solid-state silicon avalanche technology
Mechanical Characteristics
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JEDEC SO-16 package
Molding compound flammability rating: UL 94V-0
Marking : Part number, date code, logo
Packaging : Tube or Tape and Reel per EIA 481
Applications
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Circuit Diagram
ADSL/HDSL
RS-232 & RS-423
V.90
WAN/LAN Equipment
Cable Modems
Schematic & PIN Configuration
TIP
RING
SO-16 (Top View)
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LC04-12
PROTECTION PRODUCTS
Absolute Maximum Rating
R ating
Symbo l
Value
Units
Peak Pulse Pow er (tp = 10/1000µs)
Pp k
600
Watts
Peak Pulse Current (tp = 10/1000 µ s)
I PP
25
A
Peak Pulse Current (tp = 8/20µs)
I PP
100
A
Lead Soldering Temp erature
TL
260 (10 sec.)
°C
Op erating Temp erature
TJ
-55 to +125
°C
TSTG
-55 to +150
°C
Storage Temp erature
Electrical Characteristics
LC04-12
Par ame te r
Symbo l
Co nd itio ns
Minimum
Typ ical
Maximum
Units
12
V
Reverse Stand-Off Voltage
VRWM
Reverse Breakdow n Voltage
V BR
It = 1mA
Reverse Leakage Current
IR
VRWM = 12V, T=25°C
2
µA
Clamp ing Voltage
VC
IPP = 10A,
tp = 10/1000µs
19.5
V
Clamp ing Voltage
VC
IPP = 25A,
tp = 10/1000µs
24
V
Junction Cap acitance
Cj
Each Line
V R = 0V, f = 1MHz
15
pF
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LC04-12
PROTECTION PRODUCTS
Typical Characteristics
Non-Repetitive Peak Pulse Power vs. Pulse Time
Power Derating Curve
100
110
Peak Pulse Power - PPP (kW)
100
% of Rated Power or IPP
90
10
1
80
70
60
50
40
30
20
10
0
0.1
0.1
1
10
100
0
1000
25
50
110
25
Percent of IPP
80
70
e
60
Clamping Voltage - Vc (V)
Waveform
Parameters:
tr = 8µs
td = 20µs
90
-t
50
40
100
125
td = IPP/2
30
20
Clamping Voltage vs. Peak Pulse Current
(tp=8/20ms)
20
15
10
Waveform
Parameters:
tr = 8µs
td = 20µs
5
10
0
0
0
5
10
15
20
25
30
0
Time (µs)
20
40
60
80
100
120
140
160
Peak Pulse Current - Ipp (A)
Clamping Voltage vs. Peak Pulse Current
(tp=10/1000ms)
30
Clamping Voltage - Vc (V)
150
Ambient Temperature - TA ( C)
Pulse Waveform
100
75
o
Pulse Duration - tp (µs)
25
20
15
10
Waveform
Parameters:
tr = 10µs
td = 1000µs
5
0
0
5
10
15
20
25
30
Peak Pulse Current - Ipp (A)
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LC04-12
PROTECTION PRODUCTS
Applications Information
Device Connection Options
Figure 1 - Connection for Differential (Line-to-Line)
Protection of two Tip/Ring Line Pairs
The LC04-12 is designed to protect up to four highspeed data lines (two differential pairs) from transient
over-voltages which result from lightning and ESD.
Differential protection of two line pairs is achieved by
connecting the device as follows (Figure 1): Pins 1-4
are connected to line 1 of the first pair (i.e. Tip 1) and
pins 13-16 are connected to line 2 of the first pair (i.e.
Ring 1). Pins 5-8 are connected to line 1 of the second
pair (i.e. Tip 2) and pins 9-12 are connected to line two
of the second pair (i.e. Ring 2).
Common mode protection of one line pair is achieved
by connecting the device as shown in Figure 2. The
protected lines are connected at pins 1-4 and pins 912. connection to ground is made at pins 5-8 and 1316. optionally, the lines may be connected at pins 1-4
and 5-8 with pins 9-16 being connected to ground.
TIP 1
RING 1
TIP 2
RING 2
Figure 2 - Connection for Common Mode (Line-toGround) Protection of one Tip/Ring Line Pair
All pins should be connected for best results. Minimize
parasitic inductance in the protection circuit path by
keeping the trace length between the protected line
and the LC04-12 as short as possible. Ground connections should be made directly to the ground plane.
TIP
GND
GND
RING
ADSL Protection
Configuring The LC04-12 for Remote Terminal ADSL
Applications
A typical ADSL protection circuit for remote terminals is
shown in Figure 3. The LC04-12 is connected between
Tip & Ring on the transmit and receive line pairs. It
provides protection to common mode (line-to-ground)
lightning and ESD surges. It is designed to meet the
intra-building requirements of Bellcore GR-1089. To
complete the protection circuit, the LCDA12C-1 is
employed as the IC side protection element. This
device helps prevent the transceiver from latching up
by providing fine clamping of transients that are
coupled through the transformer.
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LC04-12
PROTECTION PRODUCTS
Applications Information (Continued)
Configuring The LC04-12 for Central Office ADSL
Applications
For Central Office applications, the LC04-12 can be
configured for operation to 24V with the addition of
two external steering diodes. This is accomplished by
connecting two adjacent legs of the LC04-12 in series
and adding the steering diodes as shown in Figure 4.
Each of the TVS diodes has a working voltage of 12V.
Since the voltages are additive when series connected,
the device will have a working voltage of 24V. The
power rating of the device is effectively doubled since
the surge current capability remains unchanged.
During positive duration transients, the internal TVS
diodes of the LC04-12 will be reversed biased when
the line voltage exceeds 24V. Transient current will
flow through the LC04-12 to ground. For negative
duration transient, the external steering diodes (D1 &
D2) will be forward biased when the voltage exceeds
the forward voltage (VF) of the device.
The steering diodes are required to insure that the
internal compensation diodes of the LC04-12 are not
reverse biased as this would result in their destruction.
The ES1A ultrafast rectifiers have been found to work
well in this application. These devices will survive the
Bellcore 1089 (intra-building) and ITU K.20/K.21
surges and have a repetitive reverse voltage rating of
50V, and a typical junction capacitance of 10pF.
The total capacitance seen by the line will typically be
<25pF. This is determined by the sum of the capacitance of the steering diode and 1/2 of the capacitance
of each line pair of the LC04-12.
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LC04-12
PROTECTION PRODUCTS
Typical Applications
Figure 3 - ADSL Protection (Remote Terminal)
Com p on en t
P ar t
N u m b er
D e scr i p t i o n
T VS
LC04-12
Low cap acitance
T VS diode array
D1 & D2
ES1A
Ultrafast sur face
mount rectifier
Figure 4- LC04-12 Configured for 24V Lines (ADSL Central Office)
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LC04-12
PROTECTION PRODUCTS
Outline Drawing - SO-16
Land Pattern - SO-16
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LC04-12
PROTECTION PRODUCTS
Ordering Information
P ar t
Numbe r
Wo r king
Vo ltage
Qty p e r
Reel
R e e l Size
LC04-12.TB
12V
500
7 Inch
LC04-12.TE
12V
2500
13 Inch
Note:
(1) No suffix indicates tube pack.
Contact Information
Semtech Corporation
Protection Products Division
652 Mitchell Rd., Newbury Park, CA 91320
Phone: (805)498-2111 FAX (805)498-3804
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