Metal Oxide Varistors - 25Dmm Series
Current Energy and Power Dissipation Ratings
Should transients occur in rapid succession, the average power dissipation is the energy (watt-seconds) per pulse times
the number of pulses per second. The power so developed must be within the specifications shown on the Device Ratings
and Specifications Table for the specific device. The operating values of a MOV need to be derated at high temperatures as
shown above. Because varistors only dissipate a relatively small amount of average power they are not suitable for repetitive
applications that involve substantial amounts of average power dissipation.
Figure 1A - Power Derating for Epoxy Coated
Figure 1B - Power Derating for Pholenic Coated
100
90
80
70
60
50
40
30
20
10
0
100
90
80
70
60
50
40
30
20
10
0
-55 50
60
70
80
90 100 110 120 130 140 150
o
-55
50
60
70
80
90 100 110 120 130 140 150
o
AMBIENTTEMPERATURE ( C)
AMBIENTTEMPERATURE ( C)
Peak Pulse Current Test Waveform
100
90
01
T1
T2
50
Example
8µ
µs Current Waveform:
1
20µ
10
2
O
T
TIME
1
T
1
Figure 2
T
2
Packaging
Part Number
25D
Component
Package
Packaging
Option
Quantity
200
Packaging Specification
400PCS
25.0
BOX
Specifications are subject to change without notice.
Circuit Protection
System
Page:3
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