RT8008
Typical Application Circuit
V
IN
2.2V to 5.5V
4
C
IN
4.7µF
1
EN
3
L
2.2µH
V
OUT
VIN
RT8008
LX
VOUT
GND
2
5
C
OUT
10µF
Figure 1. Fixed Voltage Regulator
L
2.2µH
V
OUT
C1
R1
5
I
R2
R2
C
OUT
10µF
V
IN
2.2V to 5.5V
4
C
IN
4.7µF
1
VIN
LX
3
RT8008
EN
GND
2
FB
V
OUT
R1
⎞
⎛
=
V
REF
x
⎜
1
+
⎟
R2
⎠
⎝
with R2 = 300kΩ to 60kΩ so the I
R2
= 2μA to 10μA,
and (R1 x C1) should be in the range between 3x10
-6
and 6x10
-6
for component selection.
Figure 2. Adjustable Voltage Regulator
Layout Guide
V
IN
C
IN
GND
C
OUT
V
OUT
V
IN
C
IN
GND
C
OUT
V
OUT
L
VIN
4
3
2
LX
GND
L
VIN
4
3
2
LX
GND
EN
C1
VOUT
5
1
EN
FB
R1
R2
5
1
GND
V
OUT
GND
Figure 3
Layout note:
1. The distance that C
IN
connects to V
IN
is as close as possible (Under 2mm).
2. C
OUT
should be placed near RT8008.
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2
DS8008-07 March 2011