RT6218A/B
Typical Application Circuit
RT6218A/B
V
IN
3
C
IN
22μF
7
R
PGOOD
4
5
C
SS
VIN
BOOT
LX
EN
PGOOD
SS
GND
1
FB
6
R
T
*
10k
R2
8
2
C
BOOT
0.1μF
L
R1
C
FF
Open
V
OUT
C
OUT
44μF
Enable
V
PGOOD
*
Note : When C
FF
is added, it is necessary to add R
T
= 10k between feedback network and chip FB pin.
Table 1. Suggested Component Values (V
IN
= 12V)
V
OUT
(V)
1.05
1.2
1.8
2.5
3.3
5
R1 (k)
10
20.5
40.2
40.2
40.2
40.2
R2 (k)
27
36
30
18
12.1
7.32
L (H)
2.2
2.2
3.6
3.6
4.7
4.7
C
OUT
(F)
44
44
44
44
44
44
C
FF
(pF)
--
--
--
22 to 68
22 to 68
22 to 68
Note 1 : All the input and output capacitances are the suggested values, which refer to the effective
capacitances, and are subject to any de-rating effect, like a DC bias.
Note 2 : For lower output voltage applications, load transient responses can also be improved by
adding a feedforward capacitor (C
FF
, 22pF to 68pF).
Copyright © 2018 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
8
DS6218A/B-01
October
2018
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
