Semiconductor Components Industries, LLC, 2002
February, 2002 Rev. 3
1
Publication Order Number:
1N5908/D
1N5908
1500 Watt Mosorb
TM
Zener
Transient Voltage Suppressors
Unidirectional*
Mosorb devices are designed to protect voltage sensitive
components from high voltage, highenergy transients. They have
excellent clamping capability, high surge capability, low zener
i m p e d a n c e a n d f a s t r e s p o n s e t i m e . T h e s e d e v i c e s a r e
ON Semiconductor's exclusive, cost-effective, highly reliable
Surmetic
TM
axial leaded package and are ideally-suited for use in
communication systems, numerical controls, process controls,
medical equipment, business machines, power supplies and many
other industrial/consumer applications, to protect CMOS, MOS and
Bipolar integrated circuits.
Specification Features:
Working Peak Reverse Voltage Range 5 V
Peak Power 1500 Watts @ 1 ms
Maximum Clamp Voltage @ Peak Pulse Current
Low Leakage < 5
A Above 10 V
Response Time is Typically < 1 ns
Mechanical Characteristics:
CASE:
Void-free, transfer-molded, thermosetting plastic
FINISH:
All external surfaces are corrosion resistant and leads are
readily solderable
MAXIMUM LEAD TEMPERATURE FOR SOLDERING PURPOSES:
230
C, 1/16
from the case for 10 seconds
POLARITY:
Cathode indicated by polarity band
MOUNTING POSITION:
Any
MAXIMUM RATINGS
Rating
Symbol
Value
Unit
Peak Power Dissipation (Note 1.)
@ T
L
25
C
P
PK
1500
Watts
Steady State Power Dissipation
@ T
L
75
C, Lead Length = 3/8
Derated above T
L
= 75
C
P
D
5.0
50
Watts
mW/
C
Thermal Resistance, JunctiontoLead
R
q
JL
20
C/W
Forward Surge Current (Note 2.)
@ T
A
= 25
C
I
FSM
200
Amps
Operating and Storage
Temperature Range
T
J
, T
stg
65 to
+175
C
1. Nonrepetitive current pulse per Figure 4 and derated above T
A
= 25
C
per Figure 2.
2. 1/2 sine wave (or equivalent square wave), PW = 8.3 ms,
duty cycle = 4 pulses per minute maximum.
* Bidirectional device will not be available in this device
AXIAL LEAD
CASE 41A
PLASTIC
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L = Assembly Location
1N5908 = JEDEC Device Code
YY = Year
WW = Work Week
Cathode
Anode
Device
Package
Shipping
ORDERING INFORMATION
1N5908
Axial Lead
500 Units/Box
1N5908RL4
Axial Lead
1500/Tape & Reel
L
1N
5908
YYWW
UniDirectional TVS
I
PP
I
F
V
I
I
R
I
T
V
RWM
V
C
V
BR
V
F
1N5908
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2
ELECTRICAL CHARACTERISTICS
(T
A
= 25
C unless
otherwise noted, V
F
= 3.5 V Max. @ I
F
(Note 3.) = 100 A)
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
ELECTRICAL CHARACTERISTICS
(T
A
= 25
C unless otherwise noted, V
F
= 3.5 V Max. @ I
F
(Note 3.
)
= 53 A)
V
RWM
Breakdown Voltage
V
C
(Volts) (Note 7.)
Device
V
RWM
(Note 5.)
I
R
@ V
RWM
V
BR
(Note 6.) (Volts)
@ I
T
Device
(Note 4.)
(Volts)
(
A)
Min
Nom
Max
(mA)
@ I
PP
= 120 A
@ I
PP
= 60 A
@ I
PP
= 30 A
1N5908
5.0
300
6.0
1.0
8.5
8.0
7.6
NOTES:
3. Square waveform, PW = 8.3 ms, Nonrepetitive duty cycle.
4. 1N5908 is JEDEC registered as a unidirectional device only (no bidirectional option)
5. A transient suppressor is normally selected according to the maximum working peak reverse voltage (V
RWM
), which should be equal to
or greater than the dc or continuous peak operating voltage level.
6. V
BR
measured at pulse test current I
T
at an ambient temperature of 25
C and minimum voltages in V
BR
are to be controlled.
7. Surge current waveform per Figure 4 and derate per Figure 2 of the General Data 1500 W at the beginning of this group
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3
Figure 1. Pulse Rating Curve
100
80
60
40
20
0
0
25
50
75
100 125 150 175
200
PEAK PULSE DERA
TING IN % OF
PEAK POWER OR CURRENT
@
T A
= 25
C
T
A
, AMBIENT TEMPERATURE (
C)
Figure 2. Pulse Derating Curve
5
4
3
2
1
25
50
75
100
125
150
175
200
P D
, STEADY
ST
A
TE POWER DISSIP
A
TION (W
A
TTS)
T
L
, LEAD TEMPERATURE (
C)
3/8
3/8
Figure 3. Steady State Power Derating
0
0
100
50
0
0
1
2
3
4
t, TIME (ms)
V
ALUE (%)
t
r
10
s
t
P
PEAK VALUE - I
PP
HALF VALUE -
I
PP
2
Figure 4. Pulse Waveform
PULSE WIDTH (t
P
) IS DEFINED
AS THAT POINT WHERE THE
PEAK CURRENT DECAYS TO 50%
OF I
PP
.
1
s
10
s
100
s
1 ms
10 ms
100
10
1
t
P
, PULSE WIDTH
P PK
, PEAK POWER (kW)
NONREPETITIVE
PULSE WAVEFORM
SHOWN IN FIGURE 5
0.1
s
Figure 5. Typical Derating Factor for Duty Cycle
DERA
TING F
ACT
OR
1 ms
10
s
1
0.7
0.5
0.3
0.05
0.1
0.2
0.01
0.02
0.03
0.07
100
s
0.1
0.2
0.5
2
5
10
50
1
20
100
D, DUTY CYCLE (%)
PULSE WIDTH
10 ms
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4
APPLICATION NOTES
RESPONSE TIME
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 capacitance
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 6.
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 7. Minimizing this overshoot is very important in the
application, since the main purpose for adding a transient
suppressor is to clamp voltage spikes. These devices have
excellent response time, typically in the picosecond range
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 Z
in
is essential to
prevent overstress of the protection device. This impedance
should be as high as possible, without restricting the circuit
operation.
DUTY CYCLE DERATING
The data of Figure 1 applies for non-repetitive conditions
and at a lead temperature of 25
C. 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.
At first glance the derating curves of Figure 5 appear to be
in error as the 10 ms pulse has a higher derating factor than
the 10
s pulse. However, when the derating factor for a
given pulse of Figure 5 is multiplied by the peak power value
of Figure 1 for the same pulse, the results follow the
expected trend.
TYPICAL PROTECTION CIRCUIT
V
in
V
L
V
V
in
V
in
(TRANSIENT)
V
L
t
d
V
V
L
V
in
(TRANSIENT)
Z
in
LOAD
OVERSHOOT DUE TO
INDUCTIVE EFFECTS
t
D
= TIME DELAY DUE TO CAPACITIVE EFFECT
t
t
Figure 6.
Figure 7.
1N5908
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5
CLIPPER BIDIRECTIONAL DEVICES
1. Clipper-bidirectional devices are available in the
1.5KEXXA series and are designated with a "CA"
suffix; for example, 1.5KE18CA. Contact your nearest
ON Semiconductor representative.
2. Clipper-bidirectional part numbers are tested in both
directions to electrical parameters in preceeding table
(except for V
F
which does not apply).
3. The 1N6267A through 1N6303A series are JEDEC
registered devices and the registration does not include
a "CA" suffix. To order clipper-bidirectional devices
one must add CA to the 1.5KE device title.
1N5908
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6
OUTLINE DIMENSIONS
1500 Watt Mosorb
Transient Voltage Suppressors Axial Leaded
MOSORB
CASE 41A04
ISSUE D
DIM
A
MIN
MAX
MIN
MAX
MILLIMETERS
0.335
0.374
8.50
9.50
INCHES
B
0.189
0.209
4.80
5.30
D
0.038
0.042
0.96
1.06
K
1.000
---
25.40
---
P
---
0.050
---
1.27
NOTES:
1. DIMENSIONING AND TOLERANCING PER ANSI
Y14.5M, 1982.
2. CONTROLLING DIMENSION: INCH.
3. LEAD FINISH AND DIAMETER UNCONTROLLED
IN DIMENSION P.
4. 041A-01 THRU 041A-03 OBSOLETE, NEW
STANDARD 041A-04.
D
K
P
P
A
K
B
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7
Notes
1N5908
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8
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4321 NishiGotanda, Shinagawaku, Tokyo, Japan 1410031
Phone: 81357402700
Email: r14525@onsemi.com
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For additional information, please contact your local
Sales Representative.
1N5908/D
Mosorb and Surmetic are trademarks of Semiconductor Components Industries, LLC.
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