RT8268 RICHTEK [Richtek Technology Corporation], RT8268 Datasheet - Page 2

• Manufacturer Part Number: RT8268
• Description: 2A, 24V, 400kHz Step-Down Converter
• Manufacturer: RICHTEK [Richtek Technology Corporation]

RT8268
Typical Application Circuit
Table 1. Recommended Component Selection
Function Block Diagram
www.richtek.com
2
V
OUT
3.3
2.5
1.8
1.2
15
10
8
5
VIN
EN
SS
(V)
R1 (kΩ)
1µA
10k
76.8
44.2
25.8
9.31
153
100
4.75V to 24V
17
3V
Chip Enable
3
V
CC
1V
V
CC
V
Comparator
IN
R2 (kΩ)
Shutdown
10µA
VA V
Regulator
-
+
10
10
10
10
10
10
10
10
Internal
CC
10µF/25V
C
10nF
FB
C
IN
SS
Gm = 920µA/V
R
0.5V
C
48.7
6.04
6.04
0.92V
7.5
34
24
16
10
(kΩ)
Comparator
UV
+
-
VIN
EN
SS
GND
400kHz/120kHz
Foldback
Control
C
+
+
-
Oscillator
RT8268
EA
C
0.82
1.2
1.5
2.2
3.9
1.5
1.5
3.9
(nF)
COMP
COMP
BOOT
SW
FB
L1 (μH)
6.8
33
33
22
22
15
10
10
Comparator
Current
+
-
Slope Comp
3.9nF
C
D1
B220A
C
10nF
C
BOOT
C
C
NC
OU T
P
10k
22
22
22
22
22
22
22
22
Logic
R
C
Current Sense
15µH
(μF)
L1
Amplifier
+
-
10k
25.8k
R1
R2
C
22µF/6.3V
OUT
DS8268-02 March 2011
V
3.3V
OUT
VA
BOOT
SW
GND