MB39A106 Datasheet, PDF (31/46 Pages) Fujitsu Component Limited. – 2-Channel DC/DC Converter IC with Overcurrent Protection Symmetrical-Phase Type

MB39A106
PC2 = ID2 × RDS (ON) × Duty (OFF)
= 3² × 0.028 × (1−0.22)
=: 0.197 W
PS2 (ON)
=
VD (Max)
× ID × tr × fOSC
6
=
15 × 3 × 16.4 × 10^−9 × 300 × 10³
6
=: 0.037 W
PS2 (OFF)
=
VD (Max) × ID (Max) × tf × fOSC
6
=
15 × 3.2 × 5.2 × 10^−9 × 300 × 10³
6
=: 0.012 W
PT2 = PC2 + PS2 (ON) + PS2 (OFF)
=: 0.197 + 0.037 + 0.012
=: 0.246 W
PT = PT1 + PT2
=: 0.115 + 0.246
=: 0.361 W
The above power dissipation figures for the IRF7901D1 are satisfied with ample margin at 2W (Ta = +100 °C) .
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