MP1518
Fixed Frequency
White LED Driver
MP1518 Rev. 1.6 www.MonolithicPower.com 1
7/25/2006 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2006 MPS. All Rights Reserved.
The Future of Analog IC Technology
TM
TM
DESCRIPTION
The MP1518 is a step-up converter designed for
driving up to 6 series white LEDs from a single
cell Lithium Ion battery. The MP1518 uses current
mode, fixed frequency architecture to regulate the
LED current, which is measured through an
external current sense resistor. Its low 104mV
feedback voltage reduces power loss and
improves efficiency. The OV pin monitors the
output voltage and turns off the converter if an
over-voltage condition is present due to an open
circuit condition.
The MP1518 includes under-voltage lockout,
current limiting and thermal overload protection
preventing damage in the event of an output
overload.
The MP1518 is available in small 6-pin TSOT23
or 8-pin QFN (2mm x 2mm) packages.
Also available is the MP1518DJE, ideal for
applications where low EMI is critical.
EVALUATION BOARD REFERENCES
Board Number Dimensions
EV0056 1.9”X x 1.8”Y x 0.4”Z
EV1518DG-00A 2.0”X x 1.8”Y x 0.4”Z
FEATURES
• On Board Power MOSFET
• Drives up to 6 Series White LEDs
• Up to 87% Efficiency
• Over 1MHz Fixed Switching Frequency
• Open Load Shutdown
• Low 104mV Feedback Voltage
• Soft-Start/PWM Dimming
• UVLO, Thermal Shutdown
• Internal Current Limit
• Available in TSOT23-6 and QFN8 Packages
APPLICATIONS
• Cell Phones
• Handheld Computers and PDAs
• Digital Still Cameras
• Small LCD Displays
“MPS” and “The Future of Analog IC Technology” are Trademarks of Monolithic
Power Systems, Inc.
TYPICAL APPLICATION
MP1518
V
IN
5V
LED1
LED2
LED3
LED4
LED5
LED6
EN
IN
EN
GND
OV
FB
SW
88
86
84
82
80
78
76
EFFICIENCY (%)
5 101520
LED CURRENT (mA)
Efficiency vs
LED Current
6 LEDS
3 LEDS
V
IN
= 3.6V
4 LEDS