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IRFP4568PBF Datasheet, PDF (5/8 Pages) International Rectifier – HEXFETPower MOSFET
IRFP4568PbF
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0.1
0.01
0.001
0.0001
1E-006
1000
100
10
D = 0.50
0.20
0.10
0.05
0.02
0.01
SINGLE PULSE
( THERMAL RESPONSE )
τJ τJ
τ1 τ1
R1R1
Ci= τi/Ri
Ci i/Ri
R2R2
τ2 τ2
R3R3 Ri (°C/W) τi (sec)
τCτ 0.06336 0.000278
τ3τ3 0.11088 0.005836
0.11484 0.053606
Notes:
1. Duty Factor D = t1/t2
2. Peak Tj = P dm x Zthjc + Tc
1E-005
0.0001
0.001
0.01
0.1
t1 , Rectangular Pulse Duration (sec)
Fig 13. Maximum Effective Transient Thermal Impedance, Junction-to-Case
Duty Cycle = Single Pulse
0.01
0.05
0.10
Allowed avalanche Current vs avalanche
pulsewidth, tav, assuming ∆Tj = 150°C and
Tstart =25°C (Single Pulse)
1
Allowed avalanche Current vs avalanche
pulsewidth, tav, assuming ∆Τ j = 25°C and
Tstart = 150°C.
0.1
1.0E-06
1.0E-05
1.0E-04
1.0E-03
1.0E-02
tav (sec)
Fig 14. Typical Avalanche Current vs.Pulsewidth
1.0E-01
900
TOP
Single Pulse
800
BOTTOM 1.0% Duty Cycle
700
ID = 103A
600
500
400
300
200
100
Notes on Repetitive Avalanche Curves , Figures 14, 15:
(For further info, see AN-1005 at www.irf.com)
1. Avalanche failures assumption:
Purely a thermal phenomenon and failure occurs at a temperature far in
excess of Tjmax. This is validated for every part type.
2. Safe operation in Avalanche is allowed as long asTjmax is not exceeded.
3. Equation below based on circuit and waveforms shown in Figures 16a, 16b.
4. PD (ave) = Average power dissipation per single avalanche pulse.
5. BV = Rated breakdown voltage (1.3 factor accounts for voltage increase
during avalanche).
6. Iav = Allowable avalanche current.
7. ∆T = Allowable rise in junction temperature, not to exceed Tjmax (assumed as
25°C in Figure 14, 15).
tav = Average time in avalanche.
D = Duty cycle in avalanche = tav ·f
ZthJC(D, tav) = Transient thermal resistance, see Figures 13)
0
25 50 75 100 125 150 175
Starting TJ , Junction Temperature (°C)
Fig 15. Maximum Avalanche Energy vs. Temperature
PD (ave) = 1/2 ( 1.3·BV·Iav) = DT/ ZthJC
Iav = 2DT/ [1.3·BV·Zth]
EAS (AR) = PD (ave)·tav
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