ACT6359
Rev0, 13-May-08
High-Efficiency, 40V Step-Up WLED Bias Supplies
FEATURES
•
High-Efficiency DC/DC WLED Bias Supply
•
Internal 40V, 0.55Ω Power MOSFET
•
Up to 10 WLEDs per String
•
500mA Peak Current
•
Supports Analog and PWM LED Dimming
•
Integrated Over-Voltage Protection (OVP)
•
Thermal Shutdown
•
Cycle-by-Cycle Over Current Protection
•
Tiny SOT23-6 Package
GENERAL DESCRIPTION
The ACT6359 step-up DC/DC converter drives
white LEDs with an externally programmable con-
stant current. This device features an integrated,
40V power MOSFET that is capable of driving up to
ten white LEDs in series, providing inherent current
matching for uniform brightness. WLED brightness
adjustment is easily achieved via simple external
circuitry, which accepts either a PWM or an analog
dimming control signal.
The ACT6359 features a variety of protection cir-
cuits, including integrated over voltage protection
(OVP), cycle-by-cycle current limiting, and thermal
shutdown protection circuitry.
The ACT6359 has a 500mA current limit, and is
available in a small 6-pin SOT23-6 package.
APPLICATIONS
•
TFT LCD Displays
•
Smart Phones
•
Portable Media Players
•
GPS/Personal Navigation Devices
SIMPLIFIED APPLICATION CIRCUIT
L1
Up to
10 WLEDs
V
OUT
R
OV2
D1
V
IN
C
IN
IN
SW
ACT6359
ON
OFF
OV
R
OV1
EN
G
FB
R
FB
C
OUT
Innovative Power
TM
-1-
www.active-semi.com
Copyright © 2008 Active-Semi, Inc.
ACTIVE-SEMI [ ACTIVE-SEMI, INC ]
