CAT3604_08 Datasheet, PDF (1/12 Pages) Catalyst Semiconductor – 4-Channel Regulated Charge Pump White LED Driver

4-Channel Regulated Charge Pump
White LED Driver
CAT3604
FEATURES
„ Drives individually up to 4 LEDs
„ Output current up to 30mA per LED
„ Digital control On/Off of each LED
„ Compatible with supply voltage of 3V to 5.5V
„ Power efficiency up to 93%
„ 2 modes of operation 1x and 1.5x
„ Automatic short circuit detect/disable
„ High-frequency Operation at 1MHz
„ Low value ceramic capacitors
„ "604" compatible pinout
„ Soft start and current limiting
„ TQFN 16-pad package, 4 x 4mm, 0.8mm max
height
APPLICATION
„ Color LCD and keypad Backlighting
„ Cellular Phones
„ Handheld Devices
„ Digital Cameras
„ PDAs
„ Portable MP3 players
ORDERING INFORMATION
Part
Number
Quantity
Package per Reel Marking
CAT3604HV4-T2 TQFN-16 ⁽¹⁾ 2000 G364
CAT3604HV4-GT2 TQFN-16 ⁽²⁾ 2000 CDBA
Notes: (1) Matte-Tin Plated Finish (RoHS-compliant).
(2) NiPdAu Plated Finish (RoHS-compliant).
TYPICAL APPLICATION CIRCUIT
1µF
DESCRIPTION
The CAT3604 is a charge pump operating in either 1x
(LDO) mode or 1.5x 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 CAT3604 drives white light-emitting diodes
(LEDs) 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 3V to 5.5V,
making the device ideal for battery-powered
applications.
LED dimming can be accomplished by several
methods including using a DC voltage 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 "zero”
quiescent current.
The CAT3604 features short circuit and overcurrent
limiting protection. The device is available in a 16-pad
TQFN package with a max height of 0.8mm.
For Ordering Information details, see page 11.
1µF
Battery
V_IN
3V to 4.2V
CIN
EN
1µF _{Control 0}
Control 1
Control 2
R_SET
24kΩ
C1+
VIN
C1- C2+ C2-
VOUT
EN CAT3604
CTR0
LED1
CTR1
LED2
CTR2
LED3
RSET _GND LED4
V_OUT
C_OUT
1µF
20mA
© Catalyst Semiconductor, Inc.
1
Characteristics subject to change without notice
Doc. No. MD-5008 Rev. J