Datasheet

IXYS Thyristor/Diode Module Types M##501-12io1 to M##501-18io1
Rating Report. Types M##501-12io1 and M##501-18io1 Issue 3 Page 5 of 10 March, 2008
8.3 D.C. Thermal Impedance Calculation
∑
=
=
−








−⋅=
np
p
t
pt
p
err
1
1
τ
Where p = 1 to n and:
n = number of terms in the series
t = Duration of heating pulse in seconds
r
t
= Thermal resistance at time t
r
p
= Amplitude of p
th
term
τ
p
= Time Constant of r
th
term
The coefficients for this device are shown in the table below:
D.C.
Term
12345
r
p
1.37×10
-3
4.86×10
-3
0.0114 0.0223 0.0221
τ
p
7.6×10
-4
8.6×10
-3
0.101 0.56 3.12
9.0 Reverse recovery ratings
(i) Q
ra
is based on 50% I
RM
chord as shown in Fig. 1
Fig. 1
(ii) Q
rr
is based on a 150 µs integration time i.e.
∫
=
s
rrrr
dtiQ
µ 150
0
.
(iii)
2
1
t
t
FactorK =