BD9141MUV Datasheet, PDF (17/19 Pages) Rohm – Output 2A or More High-efficiency Step-down Switching Regulator with Built-in Power MOSFET

BD9141MUV
Technical Note
8. Ground wiring pattern
If small-signal GND and large-current GND are provided, It will be recommended to separate the large-current GND pattern
from the small-signal GND pattern and establish a single ground at the reference point of the set PCB so that resistance to
the wiring pattern and voltage fluctuations due to a large current will cause no fluctuations in voltages of the small-signal
GND. Pay attention not to cause fluctuations in the GND wiring pattern of external parts as well.
9 . Selection of inductor
It is recommended to use an inductor with a series resistance element (DCR) 0.1Ω or less. When using an inductor over
0.1Ω, be careful to ensure adequate margins for variation between external devices and this IC, including transient as well
as static characteristics. Furthermore, in any case, it is recommended to start up the output with EN after supply voltage is
within operation range.
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2009.06 - Rev.A