ADDTEK A707

A707
HIGH VOLTAGE BOOST DRIVER WITH
3 CHANNELS CONSTANT CURRENT REGULATORS
www.addmtek.com
DESCRIPTION
FEATURES
The A707 is a high voltage Boost driver with 3 channels
adjustable constant current regulators for notebook LED
backlight applications. Three regulated current ports are
designed to provide uniform and pure DC constant current sinks
for driving LEDs within a large range VF variations. It can drive
a number of LEDs in series/parallel configuration
Users may adjust the output current from 5mA to 30mA
through an external resistor, RSET, which gives users flexibility
in controlling the light intensity of LEDs. It also could adjust
LED brightness via PWM pin with Pulse Width Modulation
signal.
A feedback circuit is built in the between of Boost Driver
and the Current Regulators. It could sense the lowest dropout
voltage among used channels to Boost Driver in order to
maintain the output voltage in optimal level. An OVP circuit is
built for open-loop protection when any string becomes open.
The thermal protection function protects IC from over
temperature damage. Also, the exposed thermal pad enhances
the package power dissipation.
High frequency DC/DC converter for LEDs.
Integrated 40V power MOSFET.
4.5V ~ 25V wide input voltage range.
3 constant-current output channels.
Output current adjustable through external resistor.
Constant output current range: 5mA~30mA.
40V output sustaining voltage for up to 10 pcs of LEDs
in series.
LED open/short protection.
TSSOP-14L Green Package.
APPLICATIONS
Automotive interior lighting
LED backlight driver for NB and Monitors.
TYPICAL APPLICATION CIRCUIT
PACKAGE PIN OUT
VOUT
VIN =4.5V~25V
L
CIN
COUT
DF
GND
ON/OFF
SW
PWM
PWM
SHDN
OUT3
BYP
CBP
A707
VIN
OUT2
SW
PWM
1
14
SHDN
2
13
GND
BYP
3
12
OUT3
VIN
4
11
OUT2
RT
5
10
OUT1
CVFB
6
9
COMP
ISET
7
8
SS
RT
TSSOP-14
(Top View)
RSET
COMP
SS
CVFB
ISET
OUT1
RT
-
CSS
RP
RSS
CP1
VLED
+
R1
R2
ORDER INFORMATION
F
TSSOP
14 pin
A707FGT
Note: The letter “G” is marked for Green parts, and letter “T” is marked for Tape & Reel.
Copyright © 2008 ADDtek Corp.
1
V1.2 -- DECEMBER 2008