TVS Diode Datasheet
© 2021 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: GD. 11/30/21
1
SMF3.3
Surface Mount – 200W
RoHS
Pb
e3
Description
Features
Maximum Ratings and Thermal Characteristics
(T
A
=25
O
C unless otherwise noted)
Parameter Symbol Value Unit
Peak Pulse Power
Dissipation at
T
A
=25ºC (Note 1)
8/20µs (Note 2)
P
PPM
2000 W
10/1000µs (Note 3)
400 W
Thermal Resistance Junction- to- Ambient R
θJA
220 °C/W
Thermal Resistance Junction- to- Lead R
θJL
100 °C/W
Operating Temperature Range T
J
-55 to 150 °C
Storage Temperature Range T
STG
-55 to 150 °C
Notes:
1. Non-repetitive current pulse, per Fig. 4 and derated above T
J
(initial) =25ºC per Fig. 3.
SMF3.3 is designed specifically to protect sensitive electronic
equipment from voltage transients induced by lightning and other
transient voltage events.
Applications
SMF3.3 devices are ideal for the protection of portable devices/
hard drives, notebooks, VCC busses, POS terminal, SSDs, power
supplies, monitors, and vulnerable circuit used in other consumer
applications.
■ 200W peak pulse power
capability at 10/1000µs
waveform, repetition rate
(duty cycle): 0.01%
■ 1200W peak pulse power
capability at 8/20us waveform
■ Excellent clamping capability
■ Compatible with industrial
standard package SOD-123FL
■ Low profile: maximum height
of 1.1mm.
■ For surface mounted
applications to optimize board
space
■ Typical failure mode is short
from over-specified voltage or
current
■ Whisker test is conducted
based on JEDEC JESD201A
per its table 4a and 4c
■ IEC 61000-4-2 ESD 30kV(Air),
30kV (Contact)
■ ESD protection of data lines
in accordance with IEC
61000-4-2
■ EFT protection of data lines in
accordance with IEC 61000-
4-4
■ Fast response time: typically
less than 1.0ns from 0 Volts
to VBR min
■ High temperature soldering:
260°C/30 seconds at
terminals
■ Built-in strain relief
■ Meet MSL level1, per J-STD-
020C, LF maximun peak of
260°C
■ Matte tin lead–free plated
■ Halogen-free and RoHS-
compliant
■ Pb-free E3 means 2nd level
interconnect is Pb-free and
the terminal finish material is
tin(Sn) (IPC/JEDEC J-STD-
609A.01)
Functional Diagram
Bi-directional
Uni-directional
Cathode
Anode
Electrical Characteristics (T
A
=25°C unless otherwise noted)
Part
Number
Marking
Code
Breakdown
Voltage V
BR
(Volts) @ I
T
Test
Current
I
T
(mA)
Reverse
Stand off
Voltage V
R
(V)
Maximum
Reverse
Leakage @ V
R
I
R
(µA)
Maximum
Peak Pulse
Current
(10/1000μS)
I
pp
(A)
Maximum
Clamping
Voltage @I
pp
(10/1000μS)
V
C
(V)
Maximum
Peak Pulse
Current
(8/20μS)
I
pp
(A)
Maximum
Clamping
Voltage @I
pp
(8/20μS)
V
C
(V)
MIN MAX
SMF3.3 33 3.4 4.3 10 3.3 0.5 30.0 6.8 120.0 10.0
Notes:
1. V
BR
measured after I
T
applied for 300µs, I
T
= sequare wave pulse or equivalent.
2. Surge current waveform per 10/1000µs exponential wave and derated per Fig.2.
3. All terms and symbols are consistent with ANSI/IEEE C62.35.
4. Surge current waveform per 8/20µs exponential wave and derated per Fig.6.
Agency Agency File Number
E230531
Agency Approvals
Uni-directional
Resources Accessories Samples
Additional Information
TVS Diode Datasheet
© 2021 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: GD. 11/30/21
2
SMF3.3
Surface Mount – 200W
Figure 3 -
Peak Pulse Power Derating Curve
I
PPM
- Peak Pulse Current, % I
RSM
0
0
50
100
150
1.0 2.0 3.0 4.0
t
r
=10µsec
Peak Value
I
PPM
I
PPM
2
T
J
=25°C
Pulse Width(td) is defined
as the point where the peak
current decays to 50% of I
PPM
10/1000µsec. Waveform
as defined by R.E.A
t
d
t-Time (ms)
Half Value
I
PPM
( )
Figure 4 -
10/1000µS Pulse Waveform
0
20
40
60
80
100
0255075 100 125 175
Peak Pulse Power (P
PP
) or Current (I
PP
)
Derating in Percentage %
150
T
J
- Initial Junction Temperature (ºC)
Ratings and Characteristic Curves (T
A
=25°C unless otherwise noted)
Voltage Transients
Time
Voltage Across TVS
Current Through TVS
Voltage or Current
Figure 1 -
TVS Transients Clamping Waveform
0.1
1
10
0.001 0.01 0.
11
t
d
-Pulse Width (ms)
P
PPM
-Peak Pulse Power (kW)
T
J
initial = T
amb
Figure 2 -
Peak Pulse Power Rating Curve
I-V Curve Characteristics
P
PPM
Peak Pulse Power Dissipation -- Max power dissipation
V
R
Stand-off Voltage -- Maximum voltage that can be applied to the
TVS without operation
V
BR
Breakdown Voltage -- Maximum voltage that flows though the
TVS at a specified test current (IT)
V
C
Clamping Voltage -- Peak voltage measured across the TVS at a
specified Ippm (peak impulse current)
I
R
Reverse Leakage Current -- Current measured at VR
V
F
Forward Voltage Drop for Uni-directional
Note: VF distribution range from 7V to 16V at IF 1mA.
Vc
V
BR
V
R
I
R
I
T
I
pp
V
Uni-directional
V
F