CAT3626
6-Channel LED Driver with I C™ Interface
FEATURES
Drives 6 LED channels
Independent current on 3 pairs of LEDs
I
2
C serial interface programming
Adjustable current to 32mA in 0.5mA step
Power efficiency up to 91%
Fractional pump 1x/1.5x
Low noise input ripple
Fixed High Frequency Operation 1MHz
“Zero” Current Shutdown Mode
Soft start and current limiting
Short circuit protection
Thermal shutdown protection
2
PRODUCT DESCRIPTION
The CAT3626 is a high efficiency 1x/1.5x fractional
charge pump with programmable dimming current in
six LED channels. To ensure uniform brightness in
LCD backlight applications, each LED channel delivers
an accurate regulated current.
Low noise and input ripple is achieved by operating at
a constant switching frequency of 1MHz which allows
the use of small external ceramic capacitors. The
1x/1.5x fractional charge pump supports a wide range
of input voltages from 3V to 5.5V with efficiency up to
91%, and is ideal for Li-Ion battery powered devices.
The LED channels are configured into three indepen-
dent pairs, each containing 2 matched channels. Each
pair can be separately programmed from zero to 32mA,
2
in 0.5mA resolution steps, using the I C serial interface.
Any individual channel can be disabled while others
remain active. When the enable input (EN) is low, the
device is in shutdown mode drawing zero current.
The device is available in a 16-pad
TQFN
package
with a max height of 0.8mm.
Package
Marking
G626
CDAJ
APPLICATIONS
RGB LEDs
LCD and keypad Backlighting
Cellular Phones, PDAs
Digital Cameras
ORDERING INFORMATION
Part Number
Package
CAT3626HV4-T2 TQFN-16
(1)
CAT3626HV4-GT2 TQFN-16
(2)
Quantity
per Reel
2000
2000
Notes:
(1) Matte-Tin Plated Finish (RoHS-compliant)
(2) NiPdAu Plated Finish (RoHS-compliant)
PIN CONFIGURATION
TQFN 16-pad 4 x 4mm
(Top View)
LEDA2 LEDB1 LEDB2 LEDC1
16
LEDA1
SDA
SCL
EN
1
2
3
4
5
VOUT
2
TYPICAL APPLICATION CIRCUIT
1µF
1µF
15
14
13
12 LEDC2
11 GND
10 C2+
9 C2-
V
IN
3V to
5.5V
C
IN
1µF
C1-
VIN
C1+
C2-
C2+
VOUT
pair A
pair B
pair C
CAT3626
LEDA1
LEDA2
LEDB1
LEDB2
LEDC1
LEDC2
GND
C
OUT
1µF
ENABLE
I
2
C Interface
EN
SDA
SCL
20mA
6
VIN
7
C1-
8
C1+
2
I C is a trademark of Philips Corporation. Catalyst Semiconductor is licensed by Philips Corporation to carry the I C bus protocol.
© Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
1
Doc. No. MD-5014 Rev. D
CATALYST [ CATALYST SEMICONDUCTOR ]
