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Monolithic Power Systems
Figure 2: MP1521 Functional Block Diagram
MP1521
High Efficiency
White LED Driver
IN
EN
OLS
REF
BRT
Internal
Regulator
& Enable
Circuit
17V
160K
1.23V
20K Open Load
Shutdown
Comparator
Bandgap
Reference
1.23V
UVLO &
Thermal
Shutdown
Control
Logic &
Output
Driv er
500nS
One-Shot
Timer
Current Limit
Comparator
Feedbac k
Comparator
0.5 W
Power
FET
0.25V
20K
10K
1.2V
SW
GND
FB1
FB2
FB3
MP1521 Rev 2.7 10/06/04
www.monolithicpower.com
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