BD9870FPS_09 Datasheet, PDF (8/12 Pages) Rohm – Simple Step-down Switching Regulator with Built-in Power MOSFET

BD9870FPS
Technical Note
3.0
2.5
2.0
1.5
1.0
0.5
0.0
0.0
VCC=8V
VCC=12V
VCC=35V
0.5
1.0
1.5
2.0
Output Current[A]
Fig.11 Driver Drain-Source Voltage vs. Output Current
100
90
80
70
60
50
40
30
20
10
0
0
VCC=8V
VCC=12V
VCC=24V
500
1000
1500
Load Current[mA]
Fig.12 Efficiency vs. Load Current
2000
7
6
Ro=50Ω
5
4
3
2
1
0
0
10
20
30
40
Input Voltage[V]
5.05
5.04
5.03
5.02
5.01
5.00
4.99
4.98
4.97
4.96
4.95
0
VCC=35V
VCC=12V
VCC=8V
500
1000
Load Current[mA]
1500
Fig.13 Output Voltage vs. Supply Voltage
6.0
5.5
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Load Current[A]
Fig.15 Over Current Protection Characteristics
Fig.14 Output Voltage vs. Load Current
STBY 0→3V
1V/div
Vo
2V/div
Ta=25_℃
Ro=5Ω
L:C10-H5R(MITSUMI)
Fig.16 Output Start-up Characteristics
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2009.05 - Rev.A