SEMTECH SLVU2.8-4.TB

SLVU2.8-4
EPD TVS Diode Array
For ESD and Latch-Up Protection
PRELIMINARY
PROTECTION PRODUCTS
Description
Features
The SLV series of transient voltage suppressors are
designed to protect low voltage, state-of-the-art CMOS
semiconductors from transients caused by electrostatic discharge (ESD), cable discharge events (CDE),
lightning and other induced voltage surges.
‹ 400 Watts peak pulse power (tp = 8/20µs)
‹ Transient protection for high speed data lines to
The devices are constructed using Semtech’s proprietary EPD process technology. The EPD process provides low standoff voltages with significant reductions
in leakage currents and capacitance over siliconavalanche diode processes. The SLVU2.8-4 features
integrated low capacitance compensation diodes that
reduce the typical capacitance to 5pF per line. This,
combined with low leakage current, means signal
integrity is preserved in high-speed applications such
as 10/100 Ethernet.
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Mechanical Characteristics
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The SLVU2.8-4 is in an SO-8 package and may be used
to protect two high-speed line pairs. The “flow-thru”
design minimizes trace inductance and reduces voltage
overshoot associated with ESD events. The low
clamping voltage of the SLVU2.8-4 minimizes the
stress on the protected IC.
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Circuit Diagram
Pin 2, 4
JEDEC SO-8 package
Molding compound flammability rating: UL 94V-0
Marking : Part number, date code, logo
Packaging : Tape and Reel
Applications
The SLV series TVS diodes will meet the surge requirements of IEC 61000-4-2, Level 4.
Pin 1, 3
IEC 61000-4-2 (ESD) ±15kV (air), ±8kV (contact)
IEC 61000-4-4 (EFT) 40A (5/50ns)
IEC 61000-4-5 (Lightning) 24A (8/20µs)
Protects two line pairs (four lines)
Comprehensive pin out for easy board layout
Low capacitance
Low leakage current
Low operating and clamping voltages
Solid-state EPD TVS process technology
10/100 Ethernet
WAN/LAN Equipment
Switching Systems
Desktops, Servers, and Notebooks
Instrumentation
Base Stations
Analog Inputs
Schematic & PIN Configuration
Pin 6, 8
Pin 5, 7
SO-8 (Top View)
Revision 1/18/2008
1
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SLVU2.8-4
PROTECTION PRODUCTS
Absolute Maximum Rating
R ating
Symbol
Value
Units
Peak Pulse Power (tp = 8/20µs)
Pp k
400
Watts
Peak Pulse Current (tp = 8/20µs)
IP P
24
A
ESD per IEC 61000-4-2 (Air)
ESD per IEC 61000-4-2 (Contact)
VESD
25
15
kV
Lead Soldering Temperature
TL
260 (10 seconds)
o
Operating Temperature
TJ
-55 to +125
o
TSTG
-55 to +150
o
Storage Temperature
C
C
C
Electrical Characteristics
SLVU2.8-4
Parameter
Reverse Stand-Off Voltage
Symbol
Conditions
Minimum
Typical
VRWM
Maximum
Units
2.8
V
Punch-Through Voltage
V PT
IPT = 2µA
3.0
V
Snap-Back Voltage
VSB
ISB = 50mA
2.8
V
Reverse Leakage Current
IR
VRWM = 2.8V, T=25°C
(Each Line)
1
µA
Clamping Voltage
VC
IPP = 2A, tp = 8/20µs
(Each Line)
5.5
V
Clamping Voltage
VC
IPP = 5A, tp = 8/20µs
(Each Line)
8.5
V
Clamping Voltage
VC
IPP = 24A, tp = 8/20µs
(Each Line)
15
V
Junction Capacitance
Cj
VR = 0V, f = 1MHz
(Each Line)
 2008 Semtech Corp.
2
5
pF
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SLVU2.8-4
PRELIMINARY
PROTECTION PRODUCTS
Typical Characteristics
Non-Repetitive Peak Pulse Power vs. Pulse Time
Power Derating Curve
110
10
100
% of Rated Power or IPP
Peak Pulse Power - Ppk (kW)
90
1
0.1
80
70
60
50
40
30
20
10
0
0.01
0.1
1
10
100
0
1000
25
75
100
125
150
o
Pulse Waveform
Clamping Voltage vs. Peak Pulse Current
110
14
100
12
Clamping Voltage - VC (V)
90
80
Percent of IPP
50
Ambient Temperature - TA ( C)
Pulse Duration - tp (µs)
70
e
-t
60
50
40
td = I PP /2
30
10
8
6
4
Waveform
Parameters:
tr = 8µs
td = 20µs
2
20
10
0
0
0
5
10
15
20
25
0
30
5
10
15
20
25
Peak Pulse Current - IPP (A)
T im e (µs)
Normalized Capacitance vs. Reverse Voltage
Insertion Loss S21
CH1
1.6
S21
LOG
10 dB/
REF 0 dB
1.4
CJ(VR) / C J(VR=0)
1.2
1
0.8
0.6
0.4
0.2
f = 1 MHz
0
0
0.5
1
1.5
2
2.5
3
Reverse Voltage - VR (V)
START
 2008 Semtech Corp.
3
.030 000 MHz
STOP 3 000. 000 000 MHz
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SLVU2.8-4
PROTECTION PRODUCTS
Applications Information
SLVU2.8-4 Circuit Diagram
Device Connection for Protection of Four Data Lines
Electronic equipment is susceptible to transient disturbances from a variety of sources including: ESD to an
open connector or interface, direct or nearby lightning
strikes to cables and wires, and charged cables “hot
plugged” into I/O ports. The SLVU2.8-4 is designed to
protect sensitive components from damage and latchup which may result from such transient events. The
SLVU2.8-4 can be configured to protect two highspeed line pairs. The device is connected as follows:
1 . Protection of two high-speed line pairs:
The SLVU2.8-4 is designed such that the data lines
are routed through the device. The first line pair
enters at pins 1 and 2 and exit at pins 8 and 7
respectively. The second line pair enters at pins 3
and 4 and exits at pins 6 and 5. The traces must
be connected at the bottom of the device as
shown.
Low Capacitance Protection of Two Differential Line
Pairs
Circuit Board Layout Recommendations for Suppression of ESD.
Good circuit board layout is critical for the suppression
of ESD induced transients. The following guidelines are
recommended:
z Place the SLVU2.8-4 near the input terminals or
connectors to restrict transient coupling.
z Minimize the path length between the TVS and the
protected line.
z Minimize all conductive loops including power and
ground loops.
z The ESD transient return path to ground should be
kept as short as possible.
z Never run critical signals near board edges.
z Use ground planes whenever possible.
 2008 Semtech Corp.
4
Line 1
1
8
Line 1
Line 2
2
7
Line 2
Line 3
3
6
Line 3
Line 4
4
5
Line 4
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SLVU2.8-4
PRELIMINARY
PROTECTION PRODUCTS
Typical Applications
10/100 Ethernet Protection Circuit
 2008 Semtech Corp.
5
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SLVU2.8-4
PROTECTION PRODUCTS
Applications Information (continued)
EPD TVS Characteristics
IPP
The SLVU2.8-4 is constructed using Semtech’s proprietary EPD technology. The structure of the EPD TVS is
vastly different from the traditional pn-junction devices.
At voltages below 5V, high leakage current and junction
capacitance render conventional avalanche technology
impractical for most applications. However, by utilizing
the EPD technology, the SLVU2.8-4 can effectively
operate at 2.8V while maintaining excellent electrical
characteristics.
ISB
IPT
VBRR
IR
VRWM
VSB VPT VC
IBRR
The EPD TVS employs a complex nppn structure in
contrast to the pn structure normally found in traditional silicon-avalanche TVS diodes. The EPD mechanism is achieved by engineering the center region of
the device such that the reverse biased junction does
not avalanche, but will “punch-through” to a conducting state. This structure results in a device with superior dc electrical parameters at low voltages while
maintaining the capability to absorb high transient
currents.
EPD TVS IV Characteristic Curve
The IV characteristic curve of the EPD device is shown
in Figure 1. The device represents a high impedance
to the circuit up to the working voltage (VRWM). During a
transient event, the device will begin to conduct as it is
biased in the reverse direction. When the punchthrough voltage (VPT) is exceeded, the device enters a
low impedance state, diverting the transient current
away from the protected circuit. When the device is
conducting current, it will exhibit a slight “snap-back” or
negative resistance characteristic due to its structure.
This must be considered when connecting the device
to a power supply rail. To return to a non-conducting
state, the current through the device must fall below
the snap-back current (approximately < 50mA).
 2008 Semtech Corp.
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SLVU2.8-4
PRELIMINARY
PROTECTION PRODUCTS
Applications Information - SPICE Model
0.8 nH
SLVU2.8-4 Spice Model
SLVU2.8-4 Spice Parameters
 2008 Semtech Corp.
Parameter
Unit
D1 (T VS)
D2 (LCR D)
IS
Amp
6.09E-14
8.57E-9
BV
Volt
3.4
420
VJ
Volt
13.8
0.62
RS
Ohm
0.389
0.15
IB V
A mp
10E-3
10E-3
CJO
Farad
24.75E-12
3.15E-12
TT
sec
2.541E-9
2.541E-9
M
--
0.145
0.113
N
--
1.1
1.1
EG
eV
1.11
1.11
7
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SLVU2.8-4
PROTECTION PRODUCTS
Outline Drawing - SO-8
A
h
D
e
N
h
H
2X E/2
E1 E
1
0.25
L
(L1)
e/2
DETAIL
B
01
A
D
aaa C
SEATING
PLANE
A2 A
C
SEE DETAIL
A
.053
.069
.010
.004
.065
.049
.012
.020
.010
.007
.189 .193 .197
.150 .154 .157
.236 BSC
.050 BSC
.010
.020
.016 .028 .041
(.041)
8
8°
0°
.004
.010
.008
1.35
1.75
0.10
0.25
1.25
1.65
0.31
0.51
0.17
0.25
4.80 4.90 5.00
3.80 3.90 4.00
6.00 BSC
1.27 BSC
0.25
0.50
0.40 0.72 1.04
(1.04)
8
0°
8°
0.10
0.25
0.20
SIDE VIEW
A1
bxN
bbb
DIMENSIONS
INCHES
MILLIMETERS
MIN NOM MAX MIN NOM MAX
A
A1
A2
b
c
D
E1
E
e
h
L
L1
N
01
aaa
bbb
ccc
c
GAGE
PLANE
2
ccc C
2X N/2 TIPS
DIM
C A-B D
NOTES:
1.
CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES).
2. DATUMS -A- AND -B- TO BE DETERMINED AT DATUM PLANE -H3. DIMENSIONS "E1" AND "D" DO NOT INCLUDE MOLD FLASH, PROTRUSIONS
OR GATE BURRS.
4. REFERENCE JEDEC STD MS-012, VARIATION AA.
Land Pattern - SO-8
X
DIM
(C)
G
C
G
P
X
Y
Z
Z
Y
DIMENSIONS
INCHES
MILLIMETERS
(.205)
.118
.050
.024
.087
.291
(5.20)
3.00
1.27
0.60
2.20
7.40
P
NOTES:
1.
THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY.
CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR
COMPANY'S MANUFACTURING GUIDELINES ARE MET.
2. REFERENCE IPC-SM-782A, RLP NO. 300A.
 2008 Semtech Corp.
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SLVU2.8-4
PRELIMINARY
PROTECTION PRODUCTS
Marking
SC YYWW
SLVU2.8
-4
1
Top View
Note:
(1) yyww = Date Code
Ordering Information
Part Number
Working
Voltage
Qty/Pkg
R eel Size
SLVU2.8-4.TB
2.8V
500/Reel
7 Inch
2.8V
500/Reel
7 Inch
2.8V
98/Tube
N /A
2.8V
98/Tube
N /A
SLVU2.8-4.TBT
(1)
SLVU2.8-4
SLVU2.8-4.T
(1)
Note:
(1) Lead-Free Product
Contact Information
Semtech Corporation
Protection Products Division
200 Flynn Road, Camarillo, CA 93012
Phone: (805)498-2111 FAX (805)498-3804
 2008 Semtech Corp.
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