1
1SMC5.0AT3/D
1SMC5.0AT3G Series,
SZ1SMC5.0AT3G Series
1500 Watt Peak Power
Zener Transient Voltage
Suppressors
Unidirectional*
The SMC series is designed to protect voltage
sensitive components from high voltage, high energy transients.
They have excellent clamping capability, high surge capability,
low zener impedance and fast response time. The SMC series is
supplied in Littelfuse exclusive, cost-effective, highly
reliable p ackage a nd is ideally sui ted for use in
communication systems, automotive, numerical controls, process
controls, medical equipment, business machines, power supplies and
many other industrial/consumer applications.
Features
Working Peak Reverse Voltage Range 5.0 V to 78 V
Standard Zener Breakdown Voltage Range 6.7 V to 91.25 V
Peak Power 1500 W @ 1 ms
ESD Rating of Class 3 (> 16 KV) per Human Body Model
Maximum Clamp Voltage @ Peak Pulse Current
Low Leakage < 5 A Above 10 V
UL 497B for Isolated Loop Circuit Protection
Maximum Temperature Coefficient Specified
Response Time is Typically < 1 ns
SZ Prefix for Automotive and Other Applications Requiring Unique
Site and Control Change Requirements; AECQ101 Qualified and
PPAP Capable
PbFree Packages are Available
Mechanical Characteristics:
CASE: Void-free, transfer-molded, thermosetting plastic
FINISH: All external surfaces are corrosion resistant and leads are
readily solderable
MAXIMUM CASE TEMPERATURE FOR SOLDERING PURPOSES:
260ºC for 10 Seconds
LEADS: Modified LBend providing more contact area to bond pads
POLARITY: Cathode indicated by molded polarity bend
MOUNTING POSITION: Any
PLASTIC SURFACE MOUNT
ZENER TRANSIENT
VOLTAGE SUPPRESSORS
5.078 VOLTS
1500 WATT PEAK POWER
Device Package Shipping
ORDERING INFORMATION
MARKING DIAGRAM
DEVICE MARKING INFORMATION
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Specifications subject to change without notice. © 2016 Littelfuse, Inc.
September 19, 2016Rev. 8
SMC
CASE 403
PLASTIC
OBSOLETE/EOL
DATE June/30/2018 PCN/ECN# LFPCN41246
REPLACED BY SMCJ Series
1SMC5.0AT3G Series, SZ1SMC5.0AT3G Series
MAXIMUM RATINGS
Rating Symbol Value Unit
Peak Power Dissipation (Note 1) @ TL = 25C, Pulse Width = 1 ms PPK 1500 W
DC Power Dissipation @ TL = 75C
Measured Zero Lead Length (Note 2)
Derate Above 75C
Thermal Resistance from JunctiontoLead
PD
RqJL
4.0
54.6
18.3
W
mW/C
C/W
DC Power Dissipation (Note 3) @ TA = 25C
Derate Above 25C
Thermal Resistance from JunctiontoAmbient
PD
RqJA
0.75
6.1
165
W
mW/C
C/W
Forward Surge Current (Note 4) @ TA = 25C IFSM 200 A
Operating and Storage Temperature Range TJ, Tstg 65 to +150 C
Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the
Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect
device reliability.
1. 10 x 1000 ms, nonrepetitive.
2. 1 in square copper pad, FR4 board.
3. FR4 board, using Littelfuse minimum recommended footprint, as shown in 403 case outline dimensions spec.
4. 1/2 sine wave (or equivalent square wave), PW = 8.3 ms, duty cycle = 4 pulses per minute maximum.
ELECTRICAL CHARACTERISTICS (TA = 25C unless
otherwise noted, VF = 3.5 V Max @ IF = 100 A) (Note 5)
Symbol Parameter
IPP Maximum Reverse Peak Pulse Current
VCClamping Voltage @ IPP
VRWM Working Peak Reverse Voltage
IRMaximum Reverse Leakage Current @ VRWM
VBR Breakdown Voltage @ IT
ITTest Current
IFForward Current
VFForward Voltage @ IF
5. 1/2 sine wave or equivalent, PW = 8.3 ms nonrepetitive duty
cycle
UniDirectional TVS
IPP
IF
V
I
IR
IT
VRWM
VCVBR
VF
2Publication Order Number:
1SMC5.0AT3/D
Specifications subject to change without notice. © 2016 Littelfuse, Inc.
September 19, 2016 − Rev. 8
1SMC5.0AT3G Series, SZ1SMC5.0AT3G Series
ELECTRICAL CHARACTERISTICS (TA = 25C unless otherwise noted)
Device*
Device
Marking
VRWM
(Note 6) IR @ VRWM
Breakdown Voltage VC @ IPP (Note 8)
VBR V (Note 7) @ ITVCIPP
VmAMin Nom Max mA V A
1SMC5.0AT3G
1SMC6.0AT3G
1SMC6.5AT3G
GDE
GDG
GDK
5.0
6.0
6.5
1000
1000
500
6.4
6.67
7.22
6.7
7.02
7.6
7.0
7.37
7.98
10
10
10
9.2
10.3
11.2
163
145.6
133.9
1SMC7.5AT3G
1SMC8.0AT3G
1SMC9.0AT3G
GDP
GDR
GDV
7.5
8.0
9.0
100
50
10
8.33
8.89
10
8.77
9.36
10.55
9.21
9.83
11.1
1
1
1
12.9
13.6
15.4
116.3
110.3
97.4
1SMC10AT3G
1SMC12AT3G
1SMC13AT3G
GDX
GEE
GEG
10
12
13
5
5
5
11.1
13.3
14.4
11.7
14
15.15
12.3
14.7
15.9
1
1
1
17
19.9
21.5
88.2
75.3
69.7
1SMC14AT3G
1SMC15AT3G
1SMC16AT3G
1SMC17AT3G
GEK
GEM
GEP
GER
14
15
16
17
5
5
5
5
15.6
16.7
17.8
18.9
16.4
17.6
18.75
19.9
17.2
18.5
19.7
20.9
1
1
1
1
23.2
24.4
26
27.6
64.7
61.5
57.7
53.3
1SMC18AT3G
1SMC20AT3G
1SMC22AT3G
1SMC24AT3G
GET
GEV
GEX
GEZ
18
20
22
24
5
5
5
5
20
22.2
24.4
26.7
21.05
23.35
25.65
28.1
22.1
24.5
26.9
29.5
1
1
1
1
29.2
32.4
35.5
38.9
51.4
46.3
42.2
38.6
1SMC26AT3G
1SMC28AT3G
1SMC30AT3G
1SMC33AT3G
GFE
GFG
GFK
GFM
26
28
30
33
5
5
5
5
28.9
31.1
33.3
36.7
30.4
32.75
35.05
38.65
31.9
34.4
36.8
40.6
1
1
1
1
42.1
45.4
48.4
53.3
35.6
33
31
28.1
1SMC36AT3G
1SMC40AT3G
1SMC43AT3G
GFP
GFR
GFT
36
40
43
5
5
5
40
44.4
47.8
42.1
46.75
50.3
44.2
49.1
52.8
1
1
1
58.1
64.5
69.4
25.8
32.2
21.6
1SMC48AT3G
1SMC51AT3G
1SMC54AT3G
1SMC58AT3G
GFX
GFZ
GGE
GGG
48
51
54
58
5
5
5
5
53.3
56.7
60
64.4
56.1
59.7
63.15
67.8
58.9
62.7
66.3
71.2
1
1
1
1
77.4
82.4
87.1
93.6
19.4
18.2
17.2
16
1SMC60AT3G
1SMC64AT3G
1SMC70AT3G
1SMC75AT3G
1SMC78AT3G
GGK
GGM
GGP
GGR
GGT
60
64
70
75
78
5
5
5
5
5
66.7
71.1
77.8
83.3
86.7
70.2
74.85
81.9
87.7
91.25
73.7
78.6
86
92.1
95.8
1
1
1
1
1
96.8
103
113
121
126
15.5
14.6
13.3
12.4
11.4
6. A transient suppressor is normally selected according to the maximum working peak reverse voltage (VRWM), which should be equal to or
greater than the DC or continuous peak operating voltage level.
7. VBR measured at pulse test current IT at an ambient temperature of 25C.
8. Surge current waveform per Figure 2 and derate per Figure 3 of the General Data 1500 Watt at the beginning of this group.
*Include SZ-prefix devices where applicable.
3Publication Order Number:
1SMC5.0AT3/D
Specifications subject to change without notice. © 2016 Littelfuse, Inc.
September 19, 2016 − Rev. 8
1SMC5.0AT3G Series, SZ1SMC5.0AT3G Series
NONREPETITIVE
PULSE WAVEFORM
SHOWN IN FIGURE 2
tP
, PULSE WIDTH
1
10
100
0.1 ms1 ms10 ms 100 ms1 ms 10 ms
Figure 1. Pulse Rating Curve
01234
0
50
100
t, TIME (ms)
VALUE (%)
HALF VALUE - IPP
2
PEAK VALUE - IPP
Figure 2. Pulse Waveform
Figure 3. Pulse Derating Curve
PEAK PULSE DERATING IN % OF
PEAK POWER OR CURRENT @ T
A= 25 C
100
80
60
40
20
00 25 50 75 100 125 150
TA, AMBIENT TEMPERATURE (C)
120
140
160
tP
PULSE WIDTH (tP) IS DEFINED
AS THAT POINT WHERE THE PEAK
CURRENT DECAYS TO 50%
OF IPP
.
DVBR, INSTANTANEOUS INCREASE IN VBR ABOVE VBR (NOM) (VOLTS
)
0.3 0.5 0.7 1 2 3 5 7 10 20 30
1000
500
200
100
50
1
2
5
10
20
TL=25C
tP=10ms
VBR(NOM)=6.8TO13V
20V
24V 43V
75V
120V
180V
Figure 4. Dynamic Impedance
Ppk, PEAK POWER (kW)
tr 10 ms
IT
, TEST CURRENT (AMPS)
UL RECOGNITION
The entire series has Underwriters Laboratory
Recognition for the classification of protectors (QVGQ2)
under the UL standard for safety 497B and File .
Many competitors only have one or two devices recognized
or have recognition in a non-protective category. Some
competitors have no recognition at all. With the UL497B
recognition, our parts successfully passed several tests
including Strike Voltage Breakdown test, Endurance
Conditioning, Temperature test, Dielectric Voltage-Withstand
test, Discharge test and several more.
Whereas, some competitors have only passed a
flammability test for the package material, we have been
recognized for much more to be included in their Protector
category.
4Publication Order Number:
1SMC5.0AT3/D
Specifications subject to change without notice. © 2016 Littelfuse, Inc.
September 19, 2016 − Rev. 8
#E128662
1SMC5.0AT3G Series, SZ1SMC5.0AT3G Series
APPLICATION NOTES
Response Time
In most applications, the transient suppressor device is
placed in parallel with the equipment or component to be
protected. In this situation, there is a time delay associated
with the capacitance of the device and an overshoot
condition associated with the inductance of the device and
the inductance of the connection method. The capacitive
effect is of minor importance in the parallel protection
scheme because it only produces a time delay in the
transition from the operating voltage to the clamp voltage as
shown in Figure 5.
The inductive effects in the device are due to actual
turn-on time (time required for the device to go from zero
current to full current) and lead inductance. This inductive
effect produces an overshoot in the voltage across the
equipment or component being protected as shown in
Figure 6. Minimizing this overshoot is very important in the
application, since the main purpose for adding a transient
suppressor is to clamp voltage spikes. The SMC series have
a very good response time, typically < 1 ns and negligible
inductance. However, external inductive effects could
produce unacceptable overshoot. Proper circuit layout,
minimum lead lengths and placing the suppressor device as
close as possible to the equipment or components to be
protected will minimize this overshoot.
Some input impedance represented by Zin is essential to
prevent overstress of the protection device. This impedance
should be as high as possible, without restricting the circuit
operation.
Duty Cycle Derating
The data of Figure 1 applies for non-repetitive conditions
and at a lead temperature of 25C. If the duty cycle increases,
the peak power must be reduced as indicated by the curves
of Figure 7. Average power must be derated as the lead or
ambient temperature rises above 25C. The average power
derating curve normally given on data sheets may be
normalized and used for this purpose.
At first glance the derating curves of Figure 7 appear to be
in error as the 10 ms pulse has a higher derating factor than
the 10 ms pulse. However, when the derating factor for a
given pulse of Figure 7 is multiplied by the peak power value
of Figure 1 for the same pulse, the results follow the
expected trend.
6Publication Order Number:
1SMC5.0AT3/D
Specifications subject to change without notice. © 2016 Littelfuse, Inc.
September 19, 2016 − Rev. 8
1SMC5.0AT3G Series, SZ1SMC5.0AT3G Series
VL
V
Vin
Vin (TRANSIENT)
VL
td
V
Vin (TRANSIENT)
OVERSHOOT DUE TO
INDUCTIVE EFFECTS
tD = TIME DELAY DUE TO CAPACITIVE EFFECT
t t
Figure 5. Figure 6.
Figure 7. Typical Derating Factor for Duty Cycle
DERATING FACTOR
1 ms
10 ms
1
0.7
0.5
0.3
0.05
0.1
0.2
0.01
0.02
0.03
0.07
100 ms
0.1 0.2 0.5 2 5 10 501 20 100
D, DUTY CYCLE (%)
PULSE WIDTH
10 ms
TYPICAL PROTECTION CIRCUIT
Vin VL
Zin
LOAD
6Publication Order Number:
1SMC5.0AT3/D
Specifications subject to change without notice. © 2016 Littelfuse, Inc.
September 19, 2016 − Rev. 8
1SMC5.0AT3G Series, SZ1SMC5.0AT3G Series
PACKAGE DIMENSIONS
SMC
DIM
A
MIN NOM MAX MIN
MILLIMETERS INCHES
A1
b
c
D
E
L
NOM MAX
HE
c
L1L A1
A
NOTES:
1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982.
2. CONTROLLING DIMENSION: INCH.
3. D DIMENSION SHALL BE MEASURED WITHIN DIMENSION P.
4. 403-01 THRU -02 OBSOLETE, NEW STANDARD 403-03.
L1
mm
inches
SOLDERING FOOTPRINT
.com
1SMC5.0AT3/D
Specifications subject to change without notice. © 2016 Littelfuse, Inc.
September 19, 2016 − Rev. 8
Information furnished is believed to be accurate and reliable. However, users should independently evaluate the suitability of and test each product
selected for their own applications. Littelfuse products are not designed for, and shall not be used for, any purpose (including, without limitation,
military, aerospace, medical, life-saving, life-sustaining or nuclear facility applications, devices intended for surgical implant into the body, or any
other application in which the failure or lack of desired operation of the product may result in personal injury, death, or property damage) other than
those expressly set forth in applicable Littelfuse product documentation. Warranties granted by Littelfuse shall be deemed void for products used for
any purpose not expressly set forth in applicable Littelfuse documentation. Littelfuse shall not be liable for any claims or damages arising out of
products used in applications not expressly intended by Littelfuse as set forth in applicable Littelfuse documentation. The sale and use of Littelfuse
products is subject to Littelfuse Terms and Conditions of Sale, unless otherwise agreed by Littelfuse.
E
b D
HE