CAT3637HV3-GT2 Datasheet, PDF (1/14 Pages) ON Semiconductor – 6-Channel Programmable High Efficiency Quad-Mode LED Driver

6-Channel Programmable High Efficiency
Quad-Mode^® LED Driver
CAT3637
FEATURES
„ High efficiency 1.33x charge pump
„ Quad-Mode charge pump: 1x, 1.33x, 1.5x, 2x
„ Drives 6 LEDs between 30mA and 0mA each
„ 1-wire EZDim^TM interface with 2mA step
„ Power efficiency up to 92%
„ Low noise input ripple in all modes
„ “Zero” current shutdown mode
„ Soft start and current limiting
„ Short circuit protection
„ Thermal shutdown protection
„ Tiny 3mm x 3mm, 16-pad TQFN package
APPLICATIONS
„ LCD Display Backlight
„ Cellular Phones
„ Digital Still Cameras
„ Handheld Devices
ORDERING INFORMATION
Part Number
CAT3637HV3-GT2
Quantity
per Reel
2000 ⁽¹⁾
Note:
(1) NiPdAu Plated Finish (RoHS-compliant)
16-lead TQFN 3mm x 3mm Package
Package
Marking
JAAM
DESCRIPTION
The CAT3637 is a high efficiency Quad-Mode fractional
charge pump that can drive up to six LEDs program-
mable by a 1-wire digital interface. The inclusion of a
1.33x fractional charge pump mode increases device
efficiency by up to 10% over traditional 1.5x charge
pumps with no added external capacitors.
Low noise input ripple is achieved by operating at a
constant switching frequency which allows the use of
small external ceramic capacitors. The multi-fractional
charge pump supports a wide range of input voltages
from 2.5V to 5.5V.
The EN/SET logic input functions as a chip enable and a
digital programming interface for setting the current in the
LED channels. The 1-wire pulse-programming interface
supports 15 linear steps from zero current to 30mA full-
brightness in 2mA steps.
The device is available in a tiny 16-pad TQFN 3 x 3mm
package with a maximum height of 0.8mm.
Catalyst Semiconductor’s Quad-Mode 1.33x, charge pump
switching architecture is patented.
For Ordering Information details, see page 13.
PIN CONFIGURATION
(top view)
16 15 14 13
LED6 1
12 C2-
LED5 2
11 C2+
LED4 3
10 C1-
LED3 4
9 C1+
5678
TYPICAL APPLICATION CIRCUIT
1µF
1µF
V_IN
2.5V CIN
to
5.5V ^1µF
1-Wire
Programming
C1-
VIN
C1+ C2- C2+
VOUT
CAT3637
EN/SET
GND
LED1
LED2
LED3
LED4
LED5
LED6
V_OUT
C_OUT
1µF
© 2008 SCILLC. All rights reserved.
1
Characteristics subject to change without notice
Doc. No. MD-5033 Rev. C