© 2000 IXYS All rights reserved
MDD 44
Fig. 5 Three phase rectifier bridge:
Power dissipation versus direct
output current and ambient
temperature
Fig. 6 Transient thermal impedance
junction to case (per diode)
RthJC for various conduction angles d:
d
DC
180°
120°
60°
30°
RthJC (K/W)
0.59
0.61
0.63
0.66
0.70
Constants for Z calculation:
thJC
i
Rthi (K/W)
ti (s)
1
0.012
0.0012
2
0.045
0.095
3
0.533
0.455
Fig. 7 Transient thermal impedance
junction to heatsink (per diode)
RthJK for various conduction angles d:
d
DC
180°
120°
60°
30°
R (K/W)
thJK
0.79
0.81
0.83
0.86
0.90
Constants for ZthJK calculation:
i
Rthi (K/W)
ti (s)
1
0.012
0.0012
2
0.045
0.095
3
0.533
0.455
4
0.2
0.495
3-3