TVS Diodes Datasheet
© 2023 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: GD. 03/27/23
1
SZ1SMA Series
Surface Mount > 400W
■ Zener Transient Overvoltage
Suppressors
■ Working Peak Reverse
Voltage Range −5V to 170V
for uni-directional and 10 V to
78 V for bi-directional
■ Standard Zener Breakdown
Voltage Range −11.1 V to
95.83 V for bi-directional, 6.4
V to 209 V for uni-directional
■ Peak Power − 400 W @ 1 ms
■ ESD Rating of Class 3 (> 16
kV) per Human Body Model
■ Response Time is Typically
< 1 ns
■ Flat Handling Surface for
Accurate Placement
■ Package Design for Top Slide
or Bottom Circuit
■ Board Mounting
■ Low Profile Package
■ Pb-free means 2nd level
interconnect is Pb-free and
the terminal finish material is
tin(Sn) (IPC/JEDEC J-STD-
609A.01)
■ SZ Prefix for Automotive and
Other Applications Requiring
Unique Site and Control
Change Requirements; AEC−
Q101 Qualified and PPAP
Capable
■ Recognized to UL 497B
as an Isolated Loop Circuit
Protector
■ RoHS-compliant and halogin-
free
Features & Benefits
The SZ1SMA 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 SZ1SMA series is supplied
in the Littelfuse exclusive, cost-effective, highly reliable package
and is ideally suited for use in communication systems,
automotive, numerical controls, process controls, medical
equipment, business machines, power supplies and many other
industrial and consumer applications.
Description
Parameter Symbol Value Unit
Peak Power Dissipation (Note 1) @ T
L
= 25°C,
Pulse Width = 1 ms
P
PK
400 W
DC Power Dissipation @ TL = 75°C Measured
Zero Lead Length (Note 2) Derate Above 75°C
Thermal Resistance from Junction-to-Lead
P
D
R
ƟJL
1. 5
20
50
W
mW/°C
��C/W
DC Power Dissipation (Note 3) @ TA = 25°C
Derate Above 25°C
Thermal Resistance from Junction-to-Ambient
P
D
R
ƟJA
0.5
4.0
250
W
mW/°C
°C/W
Forward Surge Current (Note 4) @ TA = 25°C
(for uni-directional)
I
FSM
40 A
Operating and Storage Temperature Range
T
J
T
stg
-65 to
+150
°C
Maximum Ratings and Thermal Characteristics
Stresses exceeding those listed in the Maximum Ratings table may damage the device. If any of these limits
are exceeded, device functionality should not be assumed, damage may occur and reliability may be affected.
1. 10 X 1000 µs, non−repetitive.
2. 1” square copper pad, FR−4 board.
3. FR−4 board, using Littelfuse minimum recommended footprint
4. 1/2 sine wave (or equivalent square wave), PW = 8.3 ms, duty cycle = 4 pulses per minute maximum. (for uni-
directional)
Bi-directional
Uni-directional
Agency Approvals
Agency Agency File Number
E128662
RoHS
Pb
e3
Functional Diagram
Bi-directional
Uni-directional
Cathode
Anode
Resources Accessories Samples
Additional Information
TVS Diodes Datasheet
© 2023 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: GD. 03/27/23
2
SZ1SMA Series
Surface Mount > 400W
Symbol Parameter
I
PP
Maximum Reverse Peak Pulse Current
V
C
Clamping Voltage @ I
PP
V
RWM
Working Peak Reverse Voltage
I
R
Maximum Reverse Leakage Current @ V
RWM
V
BR
Breakdown Voltage @ I
T
I
T
Test Current
I
PP
I
PP
I
R
I
T
I
T
I
R
V
RWM
V
C
V
BR
V
RWM
V
C
V
BR
For Bi-directional
I-V Curve Characteristics
(T
A
= 25°C unless otherwise noted) – For Bi-directional
Symbol Parameter
I
PP
Maximum Reverse Peak Pulse Current
V
C
Clamping Voltage @ I
PP
V
RWM
Working Peak Reverse Voltage
I
R
Maximum Reverse Leakage Current @ V
RWM
V
BR
Breakdown Voltage @ I
T
I
T
Test Current
I
F
Forward Current
V
F
Forward Voltage @ I
F
I-V Curve Characteristics
(T
A
= 25°C unless otherwise noted, V
F
= 3.5 V Max. @ I
F
= 30 A for all types) (Note 5) – For Uni-directional
5. 1/2 sine wave or equivalent, PW = 8.3 ms, non−repetitive duty cycle.
For Uni-directional
V
I