FIXED FREQUENCY WHITE LED DRIVER
FSP3301
FEATURES
On Board Power Transistor
Drives up to 6 Series White LEDs
Up to 87% Efficiency
Over 1 MHz Fixed Switching Frequency
Open Load protection
Low 104mV Feedback Voltage
PWM Dimming
UVLO
Internal Current Limit
Available in TSOT23-6L and QFN8L Packages
GENERAL DESCRIPTION
T
he FSP3301 is a step-up converter designed for
driving up to 6 series white LEDs from a single cell
Lithium Ion battery. The FSP3301 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 hold the
output voltage equal Vov if an over-voltage condition
is present due to an open circuit condition.
The FSP3301 includes under-voltage lockout, current
limiting and thermal overload protection preventing
damage in the event of an output overload.
The FSP3301 is available in small 6-pin TSOT23 or
8-pin QFN (2mm x 2mm) packages.
APPLICATIONS
Cell Phones
Handheld Computers and PDAs
Digital Still Cameras
Small LCD Displays
PIN CONFIGURATION
(1) TSOT23-6L
(Top View)
(2) QFN8L
(Top View)
Symbol
TSOT23-6L
QFN8L
1
2
3
8
1，5
6
Name
SW
GND
FB
Descriptions
Power Switch Output. SW is the drain of the internal MOSFET switch. Connect
the power inductor and output rectifier to SW. SW can swing between GND and
29V.
Ground.
Feedback Input. The FSP3301 regulates the voltage across the current sense
resistor between FB and GND. Connect a current sense resistor from the
bottom of the LED string to GND. Connect the bottom of the LED string to FB.
The regulation voltage is 104mV.
Regulator On/Off Control Input. A high input at EN turns on the converter, and a
low input turns it off. When not used, connect EN to the input source for
automatic startup. The EN pin cannot be left floating.
Over Voltage Input. OV measures the output voltage for open circuit protection.
Connect OV to the output at the top of the LED string.
Input Supply Pin. Must be locally bypassed.
4
5
6
4
3
2
EN
OV
IN
1/9
2007-4-16
FOSLINK [ FOSLINK SEMICONDUCTOR CO.,LTD ]
