Fujitsu MB39A104 Datasheet page 25

= I × R ) × Duty
D 2
P (
C DS ON
= 3 × 0.05 × 0.263
2
: = 0.118 W
) × I × tr × f
V (
D Max D
) =
P (
S ON
6
19 × 3 × 100 × 10
=
: = 0.475 W
) × I
V ( (
D Max D Max
=
P ( )
S OFF
6
19 × 3.25 × 100 × 10
=
: = 0.515 W
= P + P ) + P
P ( (
T C S ON S OFF
: = 0.118 + 0.475 + 0.515
: = 1.108 W
The above power dissipation figures for the TPC8102 are satisfied with ample margin at 2.4 W (Ta = +25 °C) .
CH2
) = 19 V output voltage V
Input voltage V (
IN Max
= 500 kHz, L = 15 µH, drain-source on resistance R
f
OSC
Drain current (Max) : I (
D Max
− V
V
IN O
) = I +
I ( ton
D Max O
2L
19 − 3.3
= 3 +
2 × 15 × 10
: = 3.18 (A)
Drain current (Min) : I (
D Min
− V
V
IN O
) = I −
I (
ton
D Min O
2L
19 − 3.3
= 3 −
2 × 15 × 10
: = 2.82 (A)
OSC
× 500 × 10
−9
3
6
) × tf × f
OSC
× 500 × 10
−9
3
6
)
= 3.3 V, drain current I
O
)
1
× × 0.174
500 × 10
−6
3
)
1
× × 0.174
500 × 10
−6
3
= 3 A, Oscillation frequency
D
) : = 50 mΩ, tr = tf : = 100 ns.
(
DS ON
MB39A104
25