CAT3604

© Catalyst Semiconductor, Inc.

1

Doc. No. MD-5008 Rev. J

Characteristics subject to change without notice

4-Channel Regulated Charge Pump

White LED Driver

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

Package

Quantity

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).

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

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.

TYPICAL APPLICATION CIRCUIT

For Ordering Information details, see page 11.

GND

Battery

3V to 4.2V

20mA

LED2

LED3

LED1

LED4

RSET

CAT3604

VIN

VOUT

1µF

1µF

CIN

C1-

C1+

C2-

C2+

1µF

1µF

24kΩ

EN

EN

CTR0

Control 0

Control 1

Control 2

CTR1

CTR2