MB3881 Datasheet, PDF (36/40 Pages) Fujitsu Component Limited. – 8-ch DC/DC Converter IC with Synchronous Rectifier for Voltage Step-up and Step-down

MB3881
s REFERENCE DATA
Conversion efficiency vs. load current
(CH1 : Down conversion method with synchronous rectification)
95
94
Iin
Q1
A
VO1
L2 ^{(2.0 V)}
93
Vin
To OUT1-1
R1
240 Ω
33 µH
IL
92
C37
C1
91
C15
2200 pF
90
To OUT1-2
89
88
87
Ta = +25 °C
2 V output
86
VCC (O) = Vin + 2.2 V
VSS (O) = Vin − 1.8 V
85
0 50 100 150 200 250 300 350 400 450 500
Vin = 2.5 V
Vin = 3 V
Vin = 3.6 V
Vin = 4.2 V
Vin = 6 V
1 µF
Q9 ^{D1 2.2 µF}
η = ^{VO1 × IL} × 100 (%)
Vin × Iin
Load current IL (mA)
Conversion efficiency vs. load current
(CH2 : Zeta method with synchronous rectification)
90
Iin
88
86
Vin
R2
75 Ω
84
To OUT2-1
C38
82
C16 ^{1 µF}
3900 pF
80
78
To OUT2-2
76
74
Ta = +25 °C
2.8 V output
72
VCC (O) = Vin + 2.2 V
VSS (O) = Vin − 1.8 V
70
0 50 100 150 200 250 300 350 400 450 500
Load current IL (mA)
Vin = 2.5 V
Vin = 3 V
Vin = 3.6 V
Vin = 4.2 V
Vin = 6 V
Q2 C10
L3
B
2.2 µF ^L4
15 µH
VO2
(2.8 V)
IL
15 µH
C2
Q10 ^{D2 2.2 µF}
η = ^{VO2 × IL} × 100 (%)
Vin × Iin
(Continued)
36