BD9109FVM-LB Datasheet, PDF (11/23 Pages) Rohm – Synchronous Buck Converter Integrated FET

BD9109FVM-LB
Application Example
1 ^VOUT
RITH
2 ITH
EN
3 ^EN
CITH
4 GND
③
VCC ₈
PVCC
SW
7
CIN
6
PGND 5
VCC
L
①
VOUT
CO
②
GND
Figure 26. Board layout
① For the sections drawn with heavy line, use thick conductor pattern as short as possible.
② Lay out the input ceramic capacitor CIN closer to the pins PVCC and PGND, and the output capacitor Co closer to the
pin PGND.
③ Lay out CITH and RITH between the pins ITH and GND as neat as possible with least necessary wiring.
Recommended Component Lists With Above Applications
Symbol
Part
Value
Manufacturer
Series
L Coil
4.7μH
Sumida
TDK
CMD6D11B
VLF5014AT-4R7M1R1
CIN Ceramic capacitor
10μF
Kyocera
CM316X5R106K10A
CO Ceramic capacitor
10μF
Kyocera
CM316X5R106K10A
CITH Ceramic capacitor
330pF
murata
GRM18 Series
RITH Resistance
30kΩ
Rohm
MCR10 3002
The parts list presented above is an example of recommended parts. Although the parts are sound, actual circuit characteristics should be checked on your
application carefully before use. Be sure to allow sufficient margins to accommodate variations between external devices and this IC when employing the
depicted circuit with other circuit constants modified. Both static and transient characteristics should be considered in establishing these margins. When
switching noise is substantial and may impact the system, a low pass filter should be inserted between the VCC and PVCC pins, and a schottky barrier
diode established between the SW and PGND pins.
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TSZ22111 • 15 • 001
11/20
TSZ02201-0J4J0AJ00600-1-2
21.Feb.2014 Rev.002