© 2019 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: 06/18/19
TVS Diodes
Surface Mount > 400W > SZ1SMA Series
Zener Transient
Overvoltage Suppressors
Working Peak Reverse
Voltage Range −5V to 70V
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 86.0 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
Features
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
SZ1SMA Series
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)
Additional Information
Samples
Resources
Datasheet
Bi-directional
Uni-directional
Agency Approvals
Agency Agency File Number
E128662
RoHS
Pb
e3
© 2019 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: 06/18/19
TVS Diodes
Surface Mount > 400W > SZ1SMA Series
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-V Curve Characteristics (T
A
= 25°C unless otherwise noted) – For Bi-directional
I
PP
I
PP
I
R
I
T
I
T
I
R
V
RWM
V
C
V
BR
V
RWM
V
C
V
BR
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
For Bi-directional
Functional Diagram
Bi-directional
Uni-directional
Cathode
Anode
V
I