© Semiconductor Components Industries, LLC, 2011

June, 2011 − Rev. 2

1

Publication Order Number:

CAT4002A/D

CAT4002A, CAT4004A

Constant Current LED

Driver with 32 Dimming

Levels and Rset

Description

The CAT4002A and CAT4004A provide respectively two and four

matched low dropout current sources to drive LEDs. The CAT400XA

uses an external resistor RSET to set the current in the LED channels.

Each LED channel includes an individual control loop allowing the

device to handle a wide range of LED forward voltages while still

maintaining tight current matching.

The EN/DIM logic inputs supports device enable and a digital

dimming interface for setting the LED channel current with 32 linear

dimming levels.

LEDs can be powered directly from a Lithium−ion battery due to the

low dropout (50 mV at 20 mA) current sinks. The device is available

in the tiny 8−pad UDFN 2 mm x 2 mm package with a max height of

0.55 mm, as well as the 6−lead TSOT−23 and SC−70.

Features

Compliant

Applications

Figure 1. Typical Application Circuit

CAT4004A

VIN

EN/DIM

RSET

GND

LED1 LED2 LED3 LED4

RSET

3.74 kW

One wire

programming

20 mA

1 mF

2.4 V

to

5.5 V

http://onsemi.com

ORDERING INFORMATION

SC70−6

SD SUFFIX

CASE 419AD

TSOT23−6

TD SUFFIX

CASE 419AF

UDFN−8

HU2G SUFFIX

CASE 517AW

PIN CONNECTIONS

CAT4004A

UDFN−8

VIN

RSET

LED4

LED3

EN/DIM

GND

LED1

LED2

1

1

RSET

LED2

EN/DIM

GND

VIN

LED1

CAT4002A

TSOT23−6

1

GND

LED2

VIN

RSET

LED1

EN/DIM

CAT4002A

SC70−6

(Top Views)

See detailed ordering and shipping information in the package

dimensions section on page 11 of this data sheet.