pm75cs1d120 Mitsumi Electronics, Corp., pm75cs1d120 Datasheet - Page 43

• Manufacturer Part Number: pm75cs1d120
• Description: Mitsubishi Ipm L1/s1-series Application Note Igbt Modules
• Manufacturer: Mitsumi Electronics, Corp.

(1) tw1<<1ms
(2) 1ms<tw1<tw2<1s
turn-off moment of tw2 while the case temperature is stationary. (See Fig.12.7)
Temperature difference between junction and case can be calculated by using the following formula.
Tj(max)=150°C, therefore the allowable case temperature Tc(max) is, Tc(max)=150- T(j-c).
R
Z
Z
Tc(max) 150
In case of short on interval or low duty as in Fig.12.5, Junction temperatures rise to the highest value at the
In this case, ripple should be considered in calculation of average power loss P1.
Using approximation similar to (1) Fig.12.9 is obtained for calculation.
th(j-c)(tw2)
th(j-c)(tw1)
th(j-c)
T(j-c) R
Tj Tc
T(j-c) R
Tj Tc
R
Z
th(j-c)(tw2)
th(j-c)
R
th(j-c)
th(j-c)
T(j-c)
th(j-c)
T(j-c)
P
P
thermal impedance between junction and case at tw2 moment
AV
thermal resistance between junction and case
thermal impedance between junction and case at tw2 moment
thermal impedance between junction and case at tw1 moment
AV
T(j-c)
P
AV
(Pav P
Z
(Tc is measured by thermo-couple.)
th(tw2)
Z
th(j-c)(tw2)
thermal resistance between junction and case
PAV Z
AV
) Z
(Tc is measured by thermo-couple.)
Power Loss and Junction Temperature
P
th(j-c)(tW2)
AV
th(j-c)(tw2)
Z
th(j-c)(tw2)
(Pl Pav) Z
Pav Z
Fig.12.7
Fig.12.8
Fig.12.9
43
Pav R
th(j-c)(tw1)
th(j-c)
th(j-c)(tw1)
Pav Z
P
AV
(Pav P
th(j-c)(tw1)
AV
P1
) Z
th(j-c)(tw2)
Sep. 2008