SC2446A Semtech Corporation, SC2446A Datasheet - Page 8

• Manufacturer Part Number: SC2446A
• Description: Dual-Phase Single or Two Output Synchronous Step-Down Controller
• Manufacturer: Semtech Corporation

POWER MANAGEMENT
Block Diagram
2005 Semtech Corp.
COMP2
CS2-
COMP1
CS1+
CS1-
REFOUT
REFIN
CS2+
IN1-
REF
IN2-
SYNC
ROSC
13
11
12
10
14
1
5
2
9
6
3
4
8
1.8V
+
-
50mV
75mV
75mV
50mV
OSCILLATOR
+
-
+
ISEN2
-
ISEN1
-
+
-
+
-
+
EA1
EA2
+
-
+
+
-
+
-
-
+
+
-
-
ILIM2
ILIM2 -
ILIM1+
ILIM1+
ILIM1 -
I
I
I
SLOPE1
0.5V
+
+
CLK
SLOPE2
+
+
SLOPE COMP
FREQUENCY
DIVIDER
ANALOG
SWITCH
SLOPE2
-
+
-
+
PWM2
PWM1
Figure 3. SC2446A Block Diagram
SEL
CLK2
CLK1
OCN2
OCN1
CLK2
0.5 (REFIN)
R
S
S
R
Soft-Start
Control 2
0.5 (REFIN)
Overload
Soft-Start
Control 1
Hiccup
Overload
Hiccup
And
Q
Q
8
And
0.5 (REFOUT)
UV
1.25V
UV
OL2
DSBL2
DSBL1
OL1
REFERENCE
0.5V
0.5V
B
Y
A
SEL
4.3/4.5V
www.DataSheet4U.com
UVLO
SC2446A
www.semtech.com
SS2/EN2
SS1/EN1
PGND
AVCC
GDL1
AGND
GDH2
GDL2
BST1
GDH1
VPN1
PVCC
VPN2
BST2
VIN2
15
17
16
22
28
23
19
20
18
21
26
25
27
24
7