SEMTECH LCDA24C-1

LCDA24C-1
Low Capacitance TVS Array
PRELIMINARY
PROTECTION PRODUCTS
Description
Features
The LCDA24C-1 is a low capacitance transient voltage
suppressor (TVS) diode array. It is designed to protect
sensitive CMOS ICs from the damaging effects of ESD
and lightning. Each device will protect one line in
common (line-to-ground) mode or one line pair in
metallic (Line-to-line) mode. They are low capacitance
(< 15pF) making them suitable for use on high-speed
telecom and datacom interfaces without signal degradation.
The configuration of the LCDA24C-1 has been optimized for easy layout on high density boards. The
small SOT-143 package minimizes required board
space. These devices will handle up to 10 Amps for an
8/20µs lightning impulse. The low inductance construction minimizes voltage overshoot during high
current surges.
The LCDA24C-1 may be used to protect ADSL interfaces, multi-protocol serial transceivers, portable
electronics, and wireless systems.
‹ Transient protection to high-speed data lines
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IEC 61000-4-2 (ESD) ±15kV (air), ±8kV (contact)
IEC 61000-4-4 (EFT) 40A (5/50ns)
IEC 61000-4-5 (Lightning) 0.5kV, 10A (8/20µs)
Configuration optimized for easy board layout
Protects one line pair
Low capacitance (<10pF) for high-speed interfaces
Low clamping voltage
Low leakage current
Operating voltage: 24V
Solid-state silicon-avalanche technology
Mechanical Characteristics
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JEDEC SOT-143 package
Lead Finish: Matte Tin
Molding compound flammability rating: UL 94V-0
Marking: Marking code
Packaging: Tape and Reel per EIA 481
Applications
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Circuit Diagram
ADSL Interfaces
RS-232, RS-422, V.90 Interfaces
Multi-Protocol Serial Transceivers
High-Speed Data Lines
Portable Electronics
WAN/LAN Equipment
Schematic & PIN Configuration
SOT-143 (Top View)
Revision 04/07/2004
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LCDA24C-1
PROTECTION PRODUCTS
Absolute Maximum Rating
R ating
Symbol
Value
Units
Peak Pulse Power (tp = 8/20µs)
Pp k
500
Watts
Peak Pulse Current (tp = 8/20µs)
IP P
10
Amps
Operating Temperature
TJ
-55 to +125
°C
TSTG
-55 to +150
°C
Storage Temperature
Electrical Characteristics (T=25oC)
Parameter
Symbol
Conditions
Minimum
Typical
Maximum
Units
24
V
Reverse Stand-Off Voltage
VRWM
Reverse Breakdown Voltage
V BR
It = 1mA
Reverse Leakage Current
IR
VRWM = 24V, T=25°C
1
µA
Clamp ing Voltage
VC
IPP = 1A, tp = 8/20µs
43
V
Clamp ing Voltage
VC
IPP = 10A, tp = 8/20µs
50
V
Peak Pulse Current
IP P
tp = 8/20µs
10
A
Junction Cap acitance
Cj
Between I/O p ins and
Ground
VR = 0V, f = 1MHz
10
pF
 2004 Semtech Corp.
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LCDA24C-1
PRELIMINARY
PROTECTION PRODUCTS
Typical Characteristics
Non-Repetitive Peak Pulse Power vs. Pulse Time
Power Derating Curve
10
110
% of Rated Power or IPP
Peak Pulse Power - Ppk (kW)
100
1
0.1
90
80
70
60
50
40
30
20
10
0
0.01
0.1
1
10
100
0
1000
25
50
75
100
125
150
Ambient Temperature - TA (oC)
Pulse Duration - tp (µs)
Pulse Waveform
Clamping Voltage vs. Peak Pulse Current
110
55
100
90
50
Percent of IPP
70
Clamping Voltage - VC (V)
80
e -t
60
50
40
td = I PP /2
30
45
40
20
35
10
Waveform:
tr = 8µs
td = 20µs
0
0
5
10
15
20
25
30
30
0
T im e (µs)
1
2
3
4
5
6
7
8
9
10
Peak Pulse Current - IPP (A)
Capacitance vs. Reverse Voltage
4.8
f - 1 MHz
Capacitance - Cj (pF)
4.7
4.6
4.5
4.4
4.3
4.2
0
5
10
15
20
25
Reverse Voltage - VR (V)
 2004 Semtech Corp.
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LCDA24C-1
PROTECTION PRODUCTS
Applications Information
Device Connection for Metallic Protection of HighSpeed Data Lines
The LCDA24C-1 is designed to protect high-speed data
lines from transient over-voltages which result from
lightning and ESD. The device is designed to protect
one line in common mode (Line-to-Ground) or one line
pair in metallic (Line-to-Line) mode. For metallic mode
protection, the input of line 1 is connected at pin 1 and
the output is connected at pin 4. Likewise, the input
of line 2 is connected at pin 2 and the output is connected at pin 3. For common mode protection, ground
either pins 1 and 4 or pins 2 and 3. The ground
connection should be made directly to the ground
plane for best results.
Line
In
1
Line
In
2
4
Line
Out
3
Line
Out
Figure 1 - Connection for Differential Protection
(Line-to-Line)
Line
In
ADSL Protection
A typical ADSL protection circuit is shown in Figure
3. A protection device with an operating voltage of
270 volts is connected on the line side of the circuit. A
high voltage device is used due to the presence of the
ring signal. Secondary IC side protection is achieved
with low voltage TVS devices. The LCDA24C-1 is
connected between to transmit line pairs. Since the
LCDA24C-1 has a working voltage of 24 volts, it may
be used on pairs with signal swings as high as +/-12
volts. The SD05C is used to protect the receive pairs.
The signal swings on these lines can be as high as +/5 volts.
1
2
4
Line
Out
3
Figure 2 - Connection for Common Mode
Protection (Line-to-Ground)
Figure 3 - Typical ADSL Protection Circuit
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LCDA24C-1
PRELIMINARY
PROTECTION PRODUCTS
Outline Drawing - SOT-143
Notes:
(1) Controlling dimension: Inch (unless otherwise specified).
(2) Dimension A and B do not include mold protrusions. Mold protrusions are .006” max.
Land Pattern - SOT-143
 2004 Semtech Corp.
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LCDA24C-1
PROTECTION PRODUCTS
Device Marking
Ordering Information
24L
Part Number
Working
Voltage
Qty per
Reel
R eel Size
LCDA24C-1.TCT
24V
3,000
7 Inch
Contact Information
Semtech Corporation
Protection Products Division
200 Flynn Road, Camarillo, CA 93012
Phone: (805)498-2111 FAX (805)498-3804
 2004 Semtech Corp.
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