EV1528DQ-00A Datasheet, PDF (1/3 Pages) Monolithic Power Systems – 9 Lamp, 20mA Preciscion WLED Driver Evaluation Board

TM
The Future of Analog IC Technology ^TM
GENERAL DESCRIPTION
The EV1528DQ-00A evaluation board is
designed for driving up to nine (9) 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 R1.
The MP1528 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 0.4Ω
power switch minimize power loss to improve
efficiency. Either a DC voltage or a PWM signal
at the BRT input can control the LED
brightness.
ELECTRICAL SPECIFICATIONS
Parameter
Input Voltage
# of WLEDs
LED Current
Symbol
V_IN
I_LED
Value
2.7 – 5.5
7–9
20
Units
V
mA
EV1528DQ-00A
9 Lamp, 20mA Preciscion
WLED Driver Evaluation Board
FEATURES
• 2.7V to 5.5V Input Voltage Range
• Drives up to 9 Series White LEDs
• Analog and Digital PWM Brightness Control
Through BRT
• Surface-Mount Components
• Fully Assembled and Tested
APPLICATIONS
• Handheld Computers
• PDAs
• PDA Phones
• Digital and Video Cameras
• Small LCD Displays
“MPS” and “The Future of Analog IC Technology” are Trademarks of Monolithic
Power Systems, Inc.
EV1528DQ-00A EVALUATION BOARD
(L x W x H) 2.0” x 1.5” x 0.5”
(5.0cm x 3.8cm x 1.4cm)
Board Number
MPS IC Number
EV1528DQ-00A
MP1528DQ
Efficiency vs
Load Current
90
80
V_IN=
5V
4.2V
70
3.6V
3V
60
50
40
0
5 10 15 20 25
LED CURRENT (mA)
MP1528_EC01
EV1528DQ-00A Rev. 1.0
www.MonolithicPower.com
1
10/11/2005
MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2005 MPS. All Rights Reserved.