Lo w -Vo lt a g e , P re c is io n S t e p -Do w n
Co n t ro lle r fo r P o rt a b le CP U P o w e r
MAX136
INPUT
V+
SYNC
TO VL
MAX1636
SKIP
IC
POWER
BST
POWER
SWITCHOVER
200kHz
V
CC
TO
300kHz
OSC
DH
LX
PWM
LOGIC
5V
LINEAR
REG.
VL
VL
+
DL
PGND
1.1V
REF.
REF
SHUTDOWN
CONTROL
SHDN
+
CSH
CSL
OFF
-
REF
SLOPE
UNDER-
VOLTAGE
FAULT
ERROR
INTEGRATOR
gm
COMPENSATION
CC
FB
-
OVERVOLTAGE
FAULT
REF
-
V
REF
-30%
-
OVP
V
+7%
-5%
60kHz
LP FILTER
REF
V
REF
-
TIMER
RESET
POWER
GOOD
-
+
0.2V
GND
Figure 2. Functional Diagram
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