TM
MP1519L – 1X, 1.5X, 2X CHARGE PUMP 3 WHITE LED DRIVER
OPERATION
The MP1519L is a charge pump that drives 3
LEDs from a 2.5V to 5.5V input voltage. It
automatically switches between 1x, 1.5x and 2x
charge pump modes to optimize efficiency while
maintaining LED current regulation.
Three drivers independently regulate the
current through the LEDs, therefore matching
LEDs are not required.
The MP1519L employs soft switching and
soft-start to prevent overloading the battery
source at turn-on and charge pump mode
switching.
While operating, the MP1519L continually
monitors the LED current and battery voltage
and automatically switches between charge
pump modes to retain LED current regulation
through all LEDs as the battery voltage
fluctuates.
BATT
BATT
5, 13
FAULT
BATTERY
SENSOR
CURRENT
SOURCE
LED1
14
FAULT
CURRENT
SOURCE
LED2
15
ENABLE
EN
12
CONTROLLER
FAULT
CURRENT
SOURCE
LED3
16
SHUTDOWN
LED
ENABLE
RADJ
11
CURRENT
GENERATOR
ISET
LED3
LED2
LED1
PUMP SOFT
MODE START
LEDC
8
C1A
1.25V
BANDGAP
REFERENCE
CHARGE PUMP
4
C1B
7
C2A
GND
3, 10
6
C2B
9
Figure 1—Functional Block Diagram
MP1519L Rev. 1.3
10/8/2007
www.MonolithicPower.com
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© 2007 MPS. All Rights Reserved.
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