MP1523
Precision 6-Lamp
White LED Driver
Monolithic Power Systems
INITIAL RELEASE
DESCRIPTION
The MP1523 is a 5-pin SOT23 step-up
converter designed for driving up to six (6)
series white LEDs from a single-cell Lithium
Ion battery. The MP1523 uses a current
limited, variable frequency architecture to
regulate the LED current, which is measured
through an external current sense resistor. Its
low 0.4V feedback threshold reduces power
loss and improves efficiency. To prevent
damage due to an open circuit condition, the
BIAS pin can measure the output voltage and
turn off the converter if an over-voltage
condition is present.
The MP1523 includes under-voltage lockout,
current limiting, and thermal overload
protection to prevent damage in the event of
an output overload. The MP1523 is available in
a small 5-pin SOT23 package.
FEATURES
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On Board Power MOSFET
Drives up to 6 White LEDs
Up to 90% Efficiency
Over 80mA Output Current Capacity
Open Load Shutdown
Low 0.4V Feedback Threshold
UVLO, Thermal Shutdown
Soft-Start
Internal Current Limiter
Available in SOT23-5 Package
Evaluation Board Available
Cell Phones
Handheld Computers and PDAs
Digital Still and Video Cameras
Small LCD Displays
APPLICATIONS
, “MPS”, “Monolithic Power Systems”, and “The Future of Analog IC
Technology” are Registered Trademarks of Monolithic Power Systems, Inc.
TYPICAL APPLICATION
V
IN
2.7V to 5.5V
A
B
100
90
5
BIAS
4
2
1
SW
Up To
6 LEDs
EFFICIENCY (%)
80
70
60
50
V
IN
= 5V
V
IN
= 4V
V
IN
= 3V
EN
EN
MP1523
FB
3
GND
MP1523-TAC-S01
5
10
15
20
LED CURRENT (mA)
25
MP1523-EC01
07/04, Rev. 1.6
www.MonolithicPower.com
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MPS [ MONOLITHIC POWER SYSTEMS ]
