RT8008
V
V
IN
OUT
}Connect feedback network behind the output capacitors.
Keep the loop area small. Place the feedback
components near the RT8008.
L1
RT8008
4
3
VIN
EN
LX
FB
C1
C2
R1
5
2
1
} Connect all analog grounds to a command node and
then connect the command node to the power ground
behind the output capacitors.
C4
10uF
GND
R2
C3
V
IN
} An example of 2-layer PCB layout is shown in Figure 7
J1
to Figure 8 for reference.
Figure 6. EVB Schematic
Figure 7. Top Layer
Suggested Inductors
Figure 8. Bottom Layer
Component
Supplier
Inductance
DCR
Current Rating
(mA)
Dimensions
(mm)
Series
(mH)
2.2
4.7
2.2
4.7
2.2
4.7
(mW)
60
TAIYO YUDEN
TAIYO YUDEN
Sumida
NR 3015
NR 3015
1480
3 x 3 x 1.5
120
75
1020
3 x 3 x 1.5
CDRH2D14
CDRH2D14
GTSD32
1500
4.5 x 3.2 x 1.55
4.5 x 3.2 x 1.55
3.85 x 3.85 x 1.8
3.85 x 3.85 x 1.8
Sumida
135
58
1000
GOTREND
GOTREND
1500
GTSD32
146
1100
Suggested Capacitors for CIN and COUT
Component Supplier
Part No.
Capacitance (mF)
Case Size
0603
TDK
C1608JB0J475M
C2012JB0J106M
4.7
10
4.7
10
10
4.7
10
10
TDK
0805
MURATA
GRM188R60J475KE19
0603
MURATA
GRM219R60J106ME19
GRM219R60J106KE19
JMK107BJ475RA
0805
MURATA
0805
TAIYO YUDEN
TAIYO YUDEN
TAIYO YUDEN
0603
JMK107BJ106MA
0603
JMK212BJ106RD
0805
www.richtek.com
12
DS8008-04 March 2007
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
