CAT4002B Datasheet, PDF (1/11 Pages) ON Semiconductor – Constant Current Programmable LED Driver with 32 Dimming Levels

CAT4002B, CAT4003B,
CAT4004B
Constant Current
Programmable LED Driver
with 32 Dimming Levels
Description
The CAT4002B, CAT4003B and CAT4004B provide respectively
two, three and four matched low dropout current sources to drive
LEDs. The CAT400XB requires no external RSET resistor; the LED
current is internally set to 25 mA when the device is first enabled.
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 input supports the 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 (75 mV at 20 mA) current sinks.
Package options are available including the 4−channel tiny 8−pad
UDFN 2 mm x 2 mm with a max height of 0.55 mm, and 2 or 3−
channel in the 6−lead TSOT−23 and SC−70.
Features
• 2, 3, 4 LED Current Sinks with Tight Matching
• 32 Dimming Levels
• Low Dropout Driver 75 mV at 20 mA
• No Switching Noise
• Shutdown Current less than 1 mA
• 25 mA Max LED Current per Channel
• Dimming via 1−wire EZDimt Interface
• Thermal Shutdown Protection
• RoHS Compliant
• 6−lead TSOT−23, SC−70, and 8−pad UDFN 2 mm x 2 mm Packages
Typical Applications
• LCD Display Backlight
• Cellular Phones
• Digital Still Cameras
http://onsemi.com
UDFN−8
HU2 SUFFIX
CASE 517AW
TSOT23−6
TD SUFFIX
CASE 419AF
SC70−6
SD SUFFIX
CASE 419AD
TYPICAL APPLICATION CIRCUIT
VIN
2.4 V ^CIN
to
5.5 V ^{1 mF}
LED1
LED2
VIN
One Wire
Programming
32 Steps
CAT4002B
EN/DIM
GND
ORDERING INFORMATION
See detailed ordering information on page 2 of this data
sheet.
© Semiconductor Components Industries, LLC, 2010
1
January, 2010 − Rev. 2
Publication Order Number:
CAT4002B/D