MB39A119 Datasheet, PDF (38/53 Pages) Fujitsu Component Limited. – DC/DC Converter IC of Synchronous Rectification for charging Li-ion battery

MB39A119
The load current satisfying the continuous current condition
Vo
Io ≥
tOFF
2L
16.8
1
≥
×
× (1−0.7)
2 × 5.2 × 10^−6
500 × 10^−3
≥ 0.97 A
Ripple current : Peak value
The peak ripple current must be within the rated current of the inductor.
If the peak ripple current is IL, it is obtained by the following formula.
IL ≥ IO
VIN−Vo
tON
2L
24−16.8
1
≥ 4.0 +
×
× 0.7
2 × 5.2 × 10^−6 500 × 10³
≥ 4.97 A
Ripple current : peak-to-peak value
If the peak-to-peak ripple current is ∆IL, it is obtained by the following formula.
VIN−Vo
∆IL =
tON
L
24−16.8
1
=
×
× 0.7
5.2 × 10^−6
500 × 10³
=: 1.94 A
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