RT6257A/B
Marking Information
RT6257AHGJ6F
2K= : Product Code
2K=DNN
DNN : Date Code
RT6257BHGJ6F
2J= : Product Code
DNN : Date Code
2J=DNN
Typical Application Circuit
V
IN
4.5V to 18V
4
C1
10µF/50V
C2
10µF/50V
2
3
RT6257A/B
6
BOOT
VIN
5
Enable
EN
GND
LX
C
BOOT
0.1µF
L
3.3µH
R1
147k
R2
20k
C
FF
47pF
C3
22µF/25V
C4
22µF/25V
V
OUT
5V
FB
1
R
T
4.99k
Table 1. Suggested Component Values
V
OUT
(V)
1
1.2
1.8
2.5
3.3
5
Note :
R1 (k)
13.3
20
40.2
63.4
90.9
147
R2 (k)
20
20
20
20
20
20
L (H)
1.2
1.2
1.5
2.2
2.8
3.3
C
OUT
(F)
44
44
44
44
44
44
R
T
(k)
4.99
4.99
4.99
4.99
4.99
4.99
C
FF
(pF)
--
--
--
47 to 82
47 to 82
47 to 82
(1) All the input and output capacitors are the suggested values, referring to the effective capacitances, subject to any
de-rating effect, like a DC bias.
(2) Considering the noise immunity, it is necessary to add R
T
= 4.99k between feedback network and chip FB pin.
Copyright
©
2018 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
2
DS6257A/B-03 October 2018
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
