© 2020 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: GD. 12/18/20
TVS Diodes
Surface Mount > 400W > SZ1SMA Series
• 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
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
Functional Diagram
Bi-directional
Uni-directional
Cathode
Anode
© 2020 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: GD. 12/18/20
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
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