CAT32_08 Datasheet, PDF (7/14 Pages) Catalyst Semiconductor – CMOS White LED Driver

CAT32
APPLICATION INFORMATION
INDUCTOR SELECTION AND EFFICIENCY
Inductor vendors are shown below. Contact the manufacturer for detailed technical data and new product
information.
Table 1: Inductor Manufacturers
Inductor
L (μH)
ELJEA4R7
4.7
ELJEA6R8
6.8
LQH3C4R7M24,
4.7
LQH32CN4R7M11
LQH3C100K24,
10
LQH32CN100K11
LB2016B4R7
4.7
LB2016B100
3.8
CMD4D06-4R7
4.7
CMD4D06-6R8
6.8
CLQ4D10-4R7
4.7
CLQ4D10-6R8
6.8
Maximum
DCR (mΩ)
180
250
260
300
250
350
216
296
162
195
Maximum
Height (mm)
2.2
2.2
Vendor
Panasonic
714.373.7334
2.2
Murata
770.436.1300
2.2
2.0
Taiyo Yuden
2.0
408.573.4150
0.8
0.8
Sumida
847.956.0666
1.2
1.2
Web
www.panasonic.com
www.murata.com
www.t-yuden.com
www.sumida.com
CAPACITOR SELECTION
Low ESR (equivalent series resistance) capacitors
should be used at the output to minimize the output
ripple voltage. The low ESR and small package options
available with multilayer ceramic capacitors make them
excellent choices. The X5R and X7R capacitor types
are preferred because they retain their capacitance
over wider voltage and temperature ranges than the
Y5V or Z5U types. A 1.0µF or 2.2µF output capacitor is
recommended for most applications.
The voltage rating of the output capacitor C2 depends
on the number of LEDs driven in series. A 10V
ceramic capacitor is recommended when driving two
LEDs. A 16V ceramic capacitor is recommended
when driving 3 or 4 LEDs.
Table 2: Ceramic Capacitor Manufacturers
Supplier
Taiyo Yuden
Murata
Kemet
Phone
408.573.4150
814.237.1431
408.986.0424
Web
www.t-yuden.com
www.murata.com
www.kemet.com
Low profile ceramic capacitors with a 1mm maximum
height/thickness are available for designs height
requirements. Ceramic capacitors also make a good
choice for the input capacitor, which should be
mounted as close as possible to the CAT32. A 2.2µF
or 4.7µF input capacitor is recommended. Table 2
shows a list of several ceramic capacitor
manufacturers. Consult the manufacturers for detailed
information as new products and package options are
introduced regularly.
© Catalyst Semiconductor, Inc.
7
Characteristics subject to change without notice
Doc. No. MD-5001 Rev. AD