RT7231/32/33/34
Typical Application Circuit
L1
1.4µH
RT7231/32/33/34
V
OUT
VIN
V
IN
SW
1.05V/4A
C1
C2
0.1µF
C6
0.1µF
10µF x 2
C7
22µF x 2
C3
R1
8.25k
VCC*
EN
BOOT
FB
Input Signal
PGOOD*
Power GOOD
R2
22k
R3
100k
VREG5
SS
C4
1µF
VS*
C5
3.9nF
GND* PGND
* : VCC pin for TSSOP-14 (Exposed Pad) only.
VS pin for TSSOP-14 (Exposed Pad) only.
GND pin for TSSOP-14 (Exposed Pad) only.
PGOOD pin for TSSOP-14 (Exposed Pad) and WDFN-10L 3x3 only.
Table 1. Suggested Component Values (VIN = 12V)
V
(V)
R1 (kΩ)
6.81
R2 (kΩ)
22.1
C3 (pF)
L1 (μH)
C7 (μF)
22 to 68
22 to 68
22 to 68
OUT
1
--
--
--
1.4
1.4
1.4
2
1.05
1.2
1.8
2.5
3.3
5
8.25
22.1
12.7
22.1
30.1
49.9
73.2
124
180
22.1
22.1
22.1
22.1
22.1
5 to 22
5 to 22
5 to 22
5 to 22
5 to 22
22 to 68
22 to 68
22 to 68
22 to 68
22 to 68
2
2
3.3
3.3
7
Copyright 2013 Richtek Technology Corporation. All rights reserved.
©
is a registered trademark of Richtek Technology Corporation.
DS7231/32/33/34-00 March 2013
www.richtek.com
7
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