TVS Diode Array
For ESD and Latch-Up Protection
PROTECTION PRODUCTS
Description
The SMS series of TVS arrays are designed to protect
sensitive electronics from damage or latch-up due to
ESD and other voltage-induced transient events. Each
device will protect up to five lines. They are available
with operating voltages of 5V, 12V, 15V and 24V. They
are unidirectional devices and may be used on lines
where the signal polarities are above ground.
TVS diodes are solid-state devices designed specifically
for transient suppression. They feature large cross-
sectional area junctions for conducting high transient
currents. They offer desirable characteristics for board
level protection including fast response time, low
operating and clamping voltage and no device degrada-
tion.
The SMS series devices may be used to meet the
immunity requirements of IEC 61000-4-2, level 4. The
low cost SOT23-6L package makes them ideal for use
in portable electronics such as cell phones, PDA’s, and
notebook computers.
SMS05C through SMS24C
Features
Transient protection for data lines to
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)
Small package for use in portable electronics
Protects five I/O lines
Working voltages: 5V, 12V, 15V and 24V
Low leakage current
Low operating and clamping voltages
Solid-state silicon avalanche technology
Mechanical Characteristics
EIAJ SOT23-6L package
Molding compound flammability rating: UL 94V-0
Marking : Marking Code
Packaging : Tape and Reel per EIA 481
Applications
Cell phone Handsets and Accessories
Microprocessor Based Equipment
Personal Digital Assistants (PDA’s)
Notebooks, Desktops, and Servers
Portable Instrumentation
Set Top Box
Peripherals
MP3 Players
Cordless Phones
Circuit Diagram
Schematic & PIN Configuration
SOT23-6L (Top View)
Revision 08/11/04
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SMS05C through SMS24C
PROTECTION PRODUCTS
Absolute Maximum Rating
Rating
Peak Pulse Power (t
p
= 8/20µs)
Peak Forward Voltage (I
F
=1A, t
p
=8/20µs)
Lead Soldering Temperature
Operating Temperature
Storage Temperature
Symbol
P
p k
V
FP
T
L
T
J
T
STG
Value
300
1.5
260 (10 sec.)
-55 to +125
-55 to +150
Units
Watts
V
°C
°C
°C
Electrical Characteristics
SMS05C
Par ame te r
Reverse Stand-Off Voltage
Reverse Breakdown Voltage
Reverse Leakage Current
Clamp ing Voltage
Clamp ing Voltage
Peak Pulse Current
Junction Cap acitance
Symbo l
V
RWM
V
BR
I
R
V
C
V
C
I
P P
C
j
I
t
= 1mA
V
RWM
= 5V, T=25°C
I
PP
= 5A, t
p
= 8/20µ s
I
PP
= 24A, t
p
= 8/20µ s
t
p
= 8/20µ s
Between I/O Pins and
Ground
V
R
= 0V, f = 1MHz
325
6
20
9.8
14.5
24
400
Co nditio ns
Minimum
Typical
Maximum
5
Units
V
V
µA
V
V
A
pF
SMS12C
Par ame te r
Reverse Stand-Off Voltage
Reverse Breakdown Voltage
Reverse Leakage Current
Clamp ing Voltage
Clamp ing Voltage
Peak Pulse Current
Junction Cap acitance
Symbo l
V
RWM
V
BR
I
R
V
C
V
C
I
P P
C
j
I
t
= 1mA
V
RWM
= 12V, T=25°C
I
PP
= 5A, t
p
= 8/20µ s
I
PP
= 15A, t
p
= 8/20µ s
t
p
= 8/20µ s
Between I/O Pins and
Ground
V
R
= 0V, f = 1MHz
135
13.3
1
19
23
15
150
Co nditio ns
Minimum
Typical
Maximum
12
Units
V
V
µA
V
V
A
pF
2004 Semtech Corp.
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SMS05C through SMS24C
PROTECTION PRODUCTS
Electrical Characteristics
(Continued)
SMS15C
Par ame te r
Reverse Stand-Off Voltage
Reverse Breakdown Voltage
Reverse Leakage Current
Clamp ing Voltage
Clamp ing Voltage
Peak Pulse Current
Junction Cap acitance
Symbo l
V
RWM
V
BR
I
R
V
C
V
C
I
P P
C
j
I
t
= 1mA
V
RWM
= 15V, T=25°C
I
PP
= 5A, t
p
= 8/20µ s
I
PP
= 12A, t
p
= 8/20µ s
t
p
= 8/20µ s
Between I/O Pins and
Ground
V
R
= 0V, f = 1MHz
100
16.7
1
24
29
12
125
Co nditio ns
Minimum
Typical
Maximum
15
Units
V
V
µA
V
V
A
pF
SMS24C
Par ame te r
Reverse Stand-Off Voltage
Reverse Breakdown Voltage
Reverse Leakage Current
Clamp ing Voltage
Clamp ing Voltage
Peak Pulse Current
Junction Cap acitance
Symbo l
V
RWM
V
BR
I
R
V
C
V
C
I
P P
C
j
I
t
= 1mA
V
RWM
= 24V, T=25°C
I
PP
= 5A, t
p
= 8/20µ s
I
PP
= 8A, t
p
= 8/20µ s
t
p
= 8/20µ s
Between I/O Pins and
Ground
V
R
= 0V, f = 1MHz
60
26.7
1
40
44
8
75
Co nditio ns
Minimum
Typical
Maximum
24
Units
V
V
µA
V
V
A
pF
2004 Semtech Corp.
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SMS05C through SMS24C
PROTECTION PRODUCTS
Typical Characteristics
Non-Repetitive Peak Pulse Power vs. Pulse Time
10
Peak Pulse Power - P
pk
(kW)
Power Derating Curve
110
100
90
% of Rated Power or I
PP
80
70
60
50
40
30
20
10
1
0.1
0.01
0.1
1
10
Pulse Duration - t
p
(µs)
100
1000
0
0
25
50
75
100
o
125
150
Ambient Temperature - T
A
( C)
Pulse Waveform
110
100
90
80
Percent of I
PP
70
60
50
40
30
20
10
0
0
5
10
15
T im e (µs)
20
25
30
td = I
PP
/2
e
-t
W aveform
Parameters:
tr = 8µs
td = 20µs
Clamping Voltage vs. Peak Pulse Current
45
40
Clamping Voltage - V
C
(V)
35
30
25
20
15
10
5
0
0
5
10
15
20
25
30
Peak Pulse Current - I
PP
(A)
SMS05C
SMS15C
SMS12C
SMS24C
Waveform
Parameters:
tr = 8µs
td = 20µs
Forward Voltage vs. Forward Current
5
4.5
Forward Voltage - V
F
(V)
4
3.5
3
2.5
2
1.5
1
0.5
0
0
5
10
15
20
25
30
35
40
45
Forward Current - I
F
(A)
Waveform
Parameters:
tr = 8µs
td = 20µs
2004 Semtech Corp.
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SMS05C through SMS24C
PROTECTION PRODUCTS
Applications Information
Device Connection for Protection of Five Data Lines
The SMSxxC is designed to protect up to five unidirec-
tional data lines. The device is connected as follows:
1. Unidirectional protection of five I/O lines is
achieved by connecting pins 1, 3, 4, 5 and 6 to the
data lines. Pin 2 is connected to ground. The
ground connection should be made directly to the
ground plane for best results. The path length is
kept as short as possible to reduce the effects of
parasitic inductance in the board traces.
Circuit Board Layout Recommendations for Suppres-
sion of ESD.
Good circuit board layout is critical for the suppression
of ESD induced transients. The following guidelines are
recommended:
Place the SMSxxC near the input terminals or
connectors to restrict transient coupling.
Minimize the path length between the SMSxxC and
the protected line.
Minimize all conductive loops including power and
ground loops.
The ESD transient return path to ground should be
kept as short as possible.
Never run critical signals near board edges.
Use ground planes whenever possible.
Matte Tin Lead Finish
Matte tin has become the industry standard lead-free
replacement for SnPb lead finishes. A matte tin finish
is composed of 100% tin solder with large grains.
Since the solder volume on the leads is small com-
pared to the solder paste volume that is placed on the
land pattern of the PCB, the reflow profile will be
determined by the requirements of the solder paste.
Therefore, these devices are compatible with both
lead-free and SnPb assembly techniques. In addition,
unlike other lead-free compositions, matte tin does not
have any added alloys that can cause degradation of
the solder joint.
Protection of Five Unidirectional Lines
SMSxxC Circuit Diagram
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