Dual High-Efficiency PWM Step-Down DC-DC Coverter
PAM2308
Typical Application
V
OUT1
C
OUT1
10μF
1
L1
PAM2308
EN1
2
LX1
VIN1
GND
FB2
EN2
10
8
9
7
6
C
IN1
4.
7μF
V
IN1
C
IN2
4.
7μF
V
IN2
FB1
GND
VIN2
4
3
5
LX2
L2
V
OUT2
C
OUT2
10 μ F
V
OUTx
=
1.
2V,1.
5V,1.8V,2. 2.8V or 3.
5V,
3V
Figure 2. Fixed Voltage Regulator
Block Diagram
VINx
OSC
FBx
FREQ
SHIFT
-
+
- + +
1
.
5M
OSC
SLOPE
COMP
PWM
COMP
IAMP
+
-
S Q
EA
R1
R2
COMP
VIN
SWITCHING
LOGIC
AND
RS LATCH
BLANKING
CIRCUIT
MAIN
SWITCH
(
PCH
)
ANTI
-
SHOOT
-
THRU
R Q
LXx
SYNCHRONOUS
RECTIFIER
(
NCH
)
ENx
0
.
6VREF
SHUTDOWN
IRCMP
+
-
GND
Power Analog Microelectronics
,
Inc
www.poweranalog.com
2
07/2008 Rev 1.0