OBSOLETE/EOL
DATE June/30/2018 PCN/ECN# LFPCN41246
REPLACED BY SMBJ Series
NSB12ANT3G
600 Watt Peak Power Zener
Transient Voltage
Suppressor
Littelfuse.com
Unidirectional
The NSB12ANT3G is designed to protect voltage sensitive
components from high voltage, high energy transients. This device has
excellent clamping capability, high surge capability, low zener
impedance and fast response time. The NSB12ANT3G is ideally
suited for use in computer hard disk drives, communication systems,
automotive, numerical controls, process controls, medical equipment,
business machines, power supplies, and many other industrial/
consumer applications.
PLASTIC SURFACE MOUNT
ZENER OVERVOLTAGE
TRANSIENT SUPPRESSOR
600 WATT PEAK POWER
Specification Features:
•Working Peak Reverse Voltage Range - 12 V
•Peak Power - 600 Watts @ 1 ms at Maximum Clamp Voltage @
Cathode
Anode
Peak Pulse Current
•ESD Rating of Class 3 (> 16 kV) per Human Body Model
•ESD Rating IEC 61000-4-2 Level 4 (> 30 kV)
•Low Leakage < 5 mA at 12 V
•UL 497B for Isolated Loop Circuit Protection
•Response Time is Typically < 1 ns
•Pb-Free Package is Available
SMB
CASE 403A
PLASTIC
MARKING DIAGRAM
Mechanical Characteristics:
CASE: Void‐free, transfer‐molded, thermosetting plastic
FINISH: All external surfaces are corrosion resistant and leads are
AYWW
LEKG
G
readily Solderable
MAXIMUM CASE TEMPERATURE FOR SOLDERING PURPOSES:
260°C for 10 Seconds
LEADS: Modified L-Bend providing more contact area to bond pads
POLARITY: Cathode indicated by polarity band
MOUNTING POSITION: Any
MAXIMUM RATINGS
A
Y
WW
LEK
G
= Assembly Location
= Year
= Work Week
= Specific Device Code
= Pb-Free Package
(Note: Microdot may be in either location)
Please See the Table on the Following Page
ORDERING INFORMATION
Device
NSB12ANT3G
Specifications subject to change without notice. © 2016 Littelfuse, Inc.
September 19, 2016 − Rev. 0
1
Package
Shipping
SMB
(Pb-Free)
2500/Tape & Reel
Publication Order Number:
NSB12AN/D
NSB12ANT3G
MAXIMUM RATINGS
Symbol
Value
Unit
Peak Power Dissipation (Note 1) @ TL = 25°C, Pulse Width = 1 ms
Rating
PPK
600
W
DC Power Dissipation @ TL = 75°C
Measured Zero Lead Length (Note 2)
Derate Above 75°C
Thermal Resistance from Junction to Lead
PD
3.0
W
RqJL
40
25
mW/°C
°C/W
RqJA
0.55
4.4
226
W
mW/°C
°C/W
TJ, Tstg
-65 to +150
°C
DC Power Dissipation (Note 3) @ TA = 25°C
Derate Above 25°C
Thermal Resistance from Junction to Ambient
PD
Operating and Storage Temperature Range
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, non-repetitive a t maximum IPPM and VCM, see electrical characteristics.
2. 1″ square copper pad, FR-4 board
3. FR-4 board, using Littelfuse minimum recommended footprint, as shown in 403A case outline dimensions spec.
ELECTRICAL CHARACTERISTICS
I
(TA = 25°C unless otherwise noted)
IPP
Maximum Reverse Peak Pulse Current
VC
Clamping Voltage @ IPP
VRWM
IR
VBR
IF
Parameter
Symbol
VC VBR VRWM
Working Peak Reverse Voltage
Maximum Reverse Leakage Current @ VRWM
V
IR VF
IT
Breakdown Voltage @ IT
IT
Test Current
IF
Forward Current
VF
Forward Voltage @ IF
IPP
Uni-Directional TVS
ELECTRICAL CHARACTERISTICS (TJ = 25°C unless otherwise noted)
Parameter
Zener Voltage (Note 5)
Reverse Leakage Current
Clamping Voltage
Forward Peak Voltage
Conditions
Symbol
Min
Typ
Max
Unit
IT = 1 mA
VBR
13.2
13.75
14.3
V
VRWM = 12 V
IR
5.0
mA
IPPM = 30.2 A
(Per Figure 1, Note 6)
VCM
19.9
V
IF = 30 A
(Note 4)
VF
3.5
V
4. 1/2 sine wave (or equivalent square wave), PW = 8.3 ms, non-repetitive duty cycle.
5. VZ measured at pulse test IT at an ambient temperature of 25°C.
6. Absolute Maximum Peak Current, IPPM.
Specifications subject to change without notice. © 2016 Littelfuse, Inc.
September 19, 2016 − Rev. 0
2
Publication Order Number:
NSB12AN/D
NSB12ANT3G
tr≤ 10 ms
100
VALUE (%)
PEAK VALUE - IPP
HALF VALUE 50
IPP
2
tP
0
0
1
2
3
160
PEAK PULSE DERATING IN % OF
PEAK POWER OR CURRENT @ TA = 25° C
PULSE WIDTH (tP) IS DEFINED AS
THAT POINT WHERE THE PEAK
CURRENT DECAYS TO 50% OF IPP.
140
120
100
80
60
40
20
0
4
0
25
50
75
100
t, TIME (ms)
TA, AMBIENT TEMPERATURE (°C)
Figure 1. 10 × 1000 ms Pulse Waveform
Figure 2. Pulse Derating Curve
125
150
TYPICAL PROTECTION CIRCUIT
Zin
LOAD
Vin
Specifications subject to change without notice. © 2016 Littelfuse, Inc.
September 19, 2016 − Rev. 0
3
VL
Publication Order Number:
NSB12AN/D
NSB12ANT3G
APPLICATION NOTES
RESPONSE TIME
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.
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 3.
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 4. Minimizing this overshoot is very important in the
application, since the main purpose for adding a transient
suppressor is to clamp voltage spikes. The SMB series have
V
DUTY CYCLE DERATING
If the duty cycle increases, the peak power must be
reduced as indicated by the curves of Figure 5. Average
power must be derated as the lead or ambient temperature
rises above 25°C. The average power derating curve
normally given on data sheets may be normalized and used
for this purpose.
V
Vin (TRANSIENT)
OVERSHOOT DUE TO
INDUCTIVE EFFECTS
Vin (TRANSIENT)
VL
VL
Vin
td
tD = TIME DELAY DUE TO CAPACITIVE EFFECT
t
t
Figure 3.
Figure 4.
1
0.7
DERATING FACTOR
0.5
0.3
0.2
PULSE WIDTH
10 ms
0.1
0.07
0.05
1 ms
0.03
100 ms
0.02
0.01
10 ms
0.1 0.2
0.5
1
2
5
10
D, DUTY CYCLE (%)
20
50 100
Figure 5. Typical Derating Factor for Duty Cycle
Specifications subject to change without notice. © 2016 Littelfuse, Inc.
September 19, 2016 − Rev. 0
4
Publication Order Number:
NSB12AN/D
NSB12ANT3G
UL RECOGNITION
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.
The entire series has Underwriters Laboratory
Recognition for the classification of protectors (QVGV2)
under the UL standard for safety 497B and File #116110.
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
Specifications subject to change without notice. © 2016 Littelfuse, Inc.
September 19, 2016 − Rev. 0
5
Publication Order Number:
NSB12AN/D
NSB12ANT3G
PACKAGE DIMENSIONS
SMB
CASE 403A-03
ISSUE F
HE
NOTES:
1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982.
2. CONTROLLING DIMENSION: INCH.
3. D DIMENSION SHALL BE MEASURED WITHIN DIMENSION P.
E
b
DIM
A
A1
b
c
D
E
HE
L
L1
D
MIN
1.90
0.05
1.96
0.15
3.30
4.06
5.21
0.76
MILLIMETERS
NOM
MAX
2.13
2.45
0.10
0.20
2.03
2.20
0.23
0.31
3.56
3.95
4.32
4.60
5.44
5.60
1.02
1.60
0.51 REF
MIN
0.075
0.002
0.077
0.006
0.130
0.160
0.205
0.030
INCHES
NOM
0.084
0.004
0.080
0.009
0.140
0.170
0.214
0.040
0.020 REF
MAX
0.096
0.008
0.087
0.012
0.156
0.181
0.220
0.063
A
L
L1
A1
c
SOLDERING FOOTPRINT
2.261
0.089
2.743
0.108
2.159
0.085
SCALE 8:1
mm Ǔ
ǒinches
Littelfuse products are not designed for, and shall not be used for, any purpose (including, without limitation, automotive, 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.
Littelfuse.com
Specifications subject to change without notice. © 2016 Littelfuse, Inc.
September 19, 2016 − Rev. 0
Publication Order Number:
NSB12AN/D
