sc2441a Semtech Corporation, sc2441a Datasheet - Page 8

• Manufacturer Part Number: sc2441a
• Description: Sc2441a 1.8v To 20v Input 2-phase Synchronous Step-down Controllers With Step-up Converter
• Manufacturer: Semtech Corporation

POWER MANAGEMENT
Block Diagram
2006 Semtech Corp.
SS1/EN1
SS2/EN2
GND
CS2-
SYNC/SHDN
CS1+
CS1-
FB2
CS2+
CKOUT
ROS C
COMP 1
FB1
COMP 2
16
PLLF
15
14
10
12
11
13
17
28
3
9
4
5
2
6
1.25V
0.5V
0.5V
-
+
25mV
25mV
SHDN
A1
OSCILLATOR
DETECTOR
+
-
+
-
ISEN2
ISEN1
+
+
-
PHAS E
+
+
-
AND
EA1
EA2
+
-
+
-
ILIM2
ILIM1
1.25V
2R
1.25V
2R
R
R
I
SEL
+
+
SLOP E2
S
S
CLK
SLOP E1
+
+
Figure 2 Functional Diagram of the Step-down Controllers
SLOP E COMP
ANALOG
SWITCH
FREQUENCY
DIVIDER
SLOP E2
-
+
-
+
PWM2
PWM1
CLK2
CLK1
A3
A2
-
1.25V
-
1.25V
CLK2
1.25V
R
S
R
S
Soft-Start
Control 2
Overload
Soft-Start
Control 1
Overload
Hiccup
Hiccup
And
Q
Q
And
8
REFERENCE
0.5V
SHDN
TG1ON
0.35V
TG2ON
SEL
DSBL2
OL2
OL1
DSBL1
FAULT
Shoot-through
Shoot-through
B
UVLO
4.3V/4.5V
Protection
Protection
Adaptive
VIN UVLO
Adaptive
Y
1.6/1.7V
A
MUX
VCC
SC2441A
www.semtech.com
CH 1
CH 2
PGND1
GDL2
GDH1
GDL1
GDH2
BST1
BST2
VCC
21
24
18
19
23
22
20
25
1
IN