MB39A112EVB-01
9.2 CH2 3.3 V output
VIN 12 V (Typ) , Vo2 3.3 V, Io 1.0 A, fOSC 2300 kHz
9.2.1 P-ch MOS FET (MCH3312 (SANYO product) )
VDS 30 V, VGS 20 V, ID 2 A, RDS (ON) 205 m (Typ) , Qg 5.5 nC (Typ)
Drain current : Peak value
The peak drain current of this FET must be within its rated current.
If the FET’s peak drain current is ID, it is obtained by the following formula.
VIN Vo2
ID IO
tON
2L
12 3.3
1
1.0
2 3.3 10 2300 103 0.275
6
1.16 A
9.2.2 Inductor (A916CY-3R3M : TOKO product)
3.3 H (tolerance 20) , rated current 2.57 A
The L value for all load current conditions
It is set so that the peak to peak value of the ripple current is 1/2 of the load current or less.
2 (VIN Vo2)
L
tON
IO
2 (12 3.3)
1
0.275
1.0
2300 103
2.08 H
The load current satisfying the continuous current condition
Vo2
2L
IO
tOFF
3.3
1
(1 0.275)
2 3.3 10 2300 103
6
0.16 A
Document Number: 002-08322 Rev. *A
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