EV0035
6 White LEDs, 20mA Precision
WLED Driver Evaluation Board
EV0035 Rev. 1.2
www.MonolithicPower.com
1
3/30/2006
MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2006 MPS. All Rights Reserved.
The Future of Analog IC Technology
TM
TM
DESCRIPTION
The EV0035 is the evaluation board for the
MP1523, which is designed for driving up to six
(6) series WLEDs from a single cell Lithium Ion
battery. The board is set up to obtain 20mA
LED current. The current can be adjusted by
varying the resistor R2.
The MP1523 uses current limited, variable
frequency architecture to regulate the LED
current while maintaining high efficiency. The
BIAS pin measures the output voltage and turns
off the converter if an over voltage condition is
present to prevent damage due to an open
circuit condition. The LED current is measured
with an external current sense resistor. The low
0.4V full-scale regulation threshold and 0.5
Ω
power switch minimize power loss to improve
efficiency.
ELECTRICAL SPECIFICATIONS
Parameter Symbol
Value
Units
Input Voltage
V
IN
2.7 – 25
V
# of WLEDs
up to 6
LED Current
I
LED
20
mA
FEATURES
•
2.7V to 25V Input Voltage Range
•
Drives up to 6 Series White LEDs
•
Surface-Mount
Components
•
Fully Assembled and Tested
APPLICATIONS
•
Cell
Phones
•
Handheld Computers and PDAs
•
Digital Still and Video Cameras
•
Small
LCD
Displays
“MPS” and “The Future of Analog IC Technology” are Trademarks of Monolithic
Power Systems, Inc.
EV0035 EVALUATION BOARD
(L x W x H) 2.0” x 1.4” x 0.5”
(5.0cm x 3.5 x 1.2cm)
Board Number
MPS IC Number
EV0035 MP1523DT
85
80
75
70
EFFICIENCY
(%)
2.5
3.0
3.5
4.0
4.5
V
IN
(V)
EV0035_AC01
Efficiency vs V
IN
