# IGBT Modules - Technologies, Driver and Application (Second Edition) - page 526

514
Fig. 14.25
Determinationof the temperature increases
T
vj
of the IGBTs
T
vj1,min
= 50°C, T
vj1,max
= 100°C
⇒∆
T
vj1
= 50K
T
vj2,min
= 60°C, T
vj2,max
= 101°C
⇒∆
T
vj2
= 41K
T
vj3,min
= 60°C, T
vj3,max
= 125°C
⇒∆
T
vj3
= 65K
From thePC chart i
and the correction factor fro
r according to
3.0
on
corr
s5.1
t
n
=
Eq. 14.13
the following number of cycle
can bedetermined
:
T
vj1
= 50K, t
on1
= 11s
n
1(1.5s)
=
6
108.0
cycles andn
corr1
=0.55
6
1 corr
)s5.1(1 1
10 44.0 n n n
= ⋅
=
cycles
T
vj2
= 41K, t
on2
= 10s
n
2(1.5s)
=
6
103.2
cycles andn
corr2
=0.57
6
2 corr
)s5.1(2 2
10 31.1 n
n n
= ⋅
=
cycles
T
vj3
= 65K, t
on3
= 2s
n
3(1.5s)
=
6
103.0
cycles andn
corr3
=0.92
6
3 corr
)s5.1(3 3
10 28.0 n
n n
= ⋅
=
cycles
For the lifetime in cycles referenced to the bond wire connections, therefore, the
following value results from the example above:
6
The indicated number of cycles in this example is always referenced to the end value or themaximum value of
junction temperature of 125°C. As the determined junction temperatures of the sample, however, are partly below
this value, effectively then, higher numbers of cycles are to be expected, although they are not further specified in
thePC chart given.
1...,516,517,518,519,520,521,522,523,524,525 527,528,529,530,531,532,533,534,535,536,...548