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IRFB4110PBF_15 Datasheet, PDF (5/9 Pages) International Rectifier – High Efficiency Synchronous Rectification in SMPS
IRFB4110PbF
1
0.1
0.01
D = 0.50
0.20
0.10
0.05
0.02
0.01
0.001
SINGLE PULSE
( THERMAL RESPONSE )
0.0001
1E-006
1E-005
τJ τJ
τ1 τ1
R 1R 1
Ci= τi/R i
Ci= τi/Ri
R 2R 2
τ2 τ2
R 3R 3
Ri (°C/W)
τCτC 0.09876251
τ3 τ3
0.2066697
0.09510464
τi (sec)
0.000111
0.001743
0.012269
Notes:
1. Duty Factor D = t1/t2
2. Peak Tj = P dm x Zthjc + Tc
0.0001
0.001
0.01
0.1
t1 , Rectangular Pulse Duration (sec)
Fig 13. Maximum Effective Transient Thermal Impedance, Junction-to-Case
1000
Duty Cycle = Single Pulse
100
0.01
Allowed avalanche Current vs avalanche
pulsewidth, tav, assuming ∆Tj = 150°C and
Tstart =25°C (Single Pulse)
0.05
10 0.10
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
tav (sec)
1.0E-03
1.0E-02
Fig 14. Typical Avalanche Current vs.Pulsewidth
1.0E-01
250
TOP
Single Pulse
BOTTOM 1.0% Duty Cycle
200
ID = 108A
150
100
50
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)
PD (ave) = 1/2 ( 1.3·BV·Iav) = DT/ ZthJC
Iav = 2DT/ [1.3·BV·Zth]
EAS (AR) = PD (ave)·tav
Fig 15. Maximum Avalanche Energy vs. Temperature
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April 28, 2014