MB39A106 Datasheet, PDF (30/46 Pages) Fujitsu Component Limited. – 2-Channel DC/DC Converter IC with Overcurrent Protection Symmetrical-Phase Type

MB39A106
PC1 = ID2 × RDS (ON) × Duty (ON)
= 3² × 0.033 × 0.22
=: 0.065 W
PS1 (ON)
=
VD (Max)
× ID × tr × fOSC
6
=
15 × 3 × 13.8 × 10^−9 × 300 × 10³
6
=: 0.031 W
PS1 (OFF)
=
VD (Max) × ID (Max) × tf × fOSC
6
=
15 × 3.2 × 8 × 10^−9 × 300 × 10³
6
=: 0.019 W
PT1 = PC1 + PS1 (ON) + PS1 (OFF)
=: 0.065 + 0.031 + 0.019
=: 0.115 W
CH1 (Synchronous rectification side)
Input voltage VIN (Max) = 15 V, output voltage VO = 3.3 V, drain current ID = 3 A, oscillation frequency
fOSC = 300 kHz, L = 22 µH, drain-source on resistance RDS (ON) =: 28 mΩ, tr = 16.4 ns, tf = 5.2 ns.
Drain current (Max) : ID (Max)
ID (Max) = IO +
VO
2L
toff
=3 +
3.3
2 × 22 × 10^−6
=: 3.20 (A)
×
1
300 × 10³
× (1−0.22)
Drain current (Min) : ID (Min)
ID (Min) = IO −
VO
2L
toff
=3
−
3.3
2 × 22 × 10^−6
×
1
300 × 10³
×
(1−0.22)
=: 2.80 (A)
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