SE3362 Datasheet, PDF (1/8 Pages) Seaward Electronics Inc. – 4-Channel Regulated Charge Pump White LED Driver

Description
The SE3362 is a charge pump operating in either
1x mode or 2x fractional mode regulating current
through each of the 4 LED pins. Operation at a fixed
high frequency of 1MHz typical allows the use of
very small value ceramic capacitors.
The SE3362 drives white light-emitting diodes
(LED’s) connected in parallel and provides tightly
matched regulated current to achieve uniformity of
brightness in LCD backlighting applications. An
external resistor RSET controls the output current
level. LED currents of up to 30mA are supported
over a range of input supply voltages from 2.85V to
5.5V, making the device ideal for battery-powered
applications.
LED dimming can be accomplished by several
methods including using a resistor Rset (the exact
formula will be provided in the Application
Section) to set the RSET pin current, applying a
PWM signal on the Control signals, or adding a
switched resistor in parallel with Rset. The Enable
input pin allows the device to be placed in
power-down mode with close to "zero” quiescent
current. The SE3362 features short circuit and Over
Temperature Protection (OTP). The device is
available in a 16- lead thin QFN package with a max
height of 0.8mm.
Application Diagram
Features
¾ Drives individually up to 4 LEDs
¾ Output current up to 30mA per LED
¾ Digital control On/Off of each LED
¾ Compatible with supply voltage of 2.85V to 5.5V
¾ Power efficiency up to 90%
¾ 2 modes of operation 1x and 2x
¾ Automatic short circuit detect/disable
¾ High-frequency Operation at 1MHz
¾ Low value ceramic capacitors
¾ Automatically switch to power save mode if no
LED is deteted to be connected to the IC
¾ Thin QFN 16-lead package, 3×3mm
¾ 100% Lead (Pb)-Free
Application
¾ Color LCD and keypad Backlighting
¾ Cellular Phones
¾ Handheld Devices
¾ Digital Cameras
¾ PDAs
¾ Portable MP3 players
Revision 12/4/2008
Preliminary and all contents are subject to change without prior notice
© Seaward Electronics, Inc., 2007. • www.seawardinc.com.cn • Page 1