Datasheet

LT3465/LT3465A
8
3465afa
skipping using a 1k resistor from FB to GND. The photo
in Figure 3b details circuit operation driving three white
LEDs at a 0.2mA load. Peak inductor current is less
than 30mA.
Inductor Selection
A 22µH inductor is recommended for most LT3465 appli-
cations. Although small size and high efficiency are major
concerns, the inductor should have low core losses at
1.2MHz and low DCR (copper wire resistance). Some
inductors in this category with small size are listed in
Table 1. The efficiency comparison of different inductors
is shown in Figure 4a. A 22µH or 10µH inductor is recom-
mended for most LT3465A applications. The inductor
should have low core losses at 2.4MHz and low DCR. The
efficiency comparison of different inductors is shown in
figure 4b.
Table 1. Recommended Inductors
PART CURRENT RATING
NUMBER DCR (Ω) (mA) MANUFACTURER
LQH32CN220 0.71 250 Murata
LQH2MCN220 2.4 185 814-237-1431
www.murata.com
ELJPC220KF 4.0 160 Panasonic
714-373-7334
www.panasonic.com
CDRH3D16-220 0.53 350 Sumida
847-956-0666
www.sumida.com
LB2012B220M 1.7 75 Taiyo Yuden
408-573-4150
www.t-yuden.com
LEM2520-220 5.5 125 Taiyo Yuden
408-573-4150
www.t-yuden.com
LED CURRENT (mA)
0
70
75
15
3465A F04b
65
60
510 20
55
50
80
EFFICIENCY (%)
V
IN
= 3.6V
4 LEDs
MURATA LQH32CN220
MURATA LQH32CN100
MURATA LQH2MCN220
TOKO D312-220
TOKO D312-100
TAIYO YUDEN LB2012B220
APPLICATIO S I FOR ATIO
WUUU
Capacitor Selection
The small size of ceramic capacitors makes them ideal for
LT3465 and LT3465A applications. X5R and X7R types are
recommended because they retain their capacitance over
wider voltage and temperature ranges than other types
such as Y5V or Z5U. A 1µF input capacitor and a 0.22µF
output capacitor are sufficient for most LT3465 and
LT3465A applications.
Table 2. Recommended Ceramic Capacitor Manufacturers
MANUFACTURER PHONE URL
Taiyo Yuden 408-573-4150 www.t-yuden.com
Murata 814-237-1431 www.murata.com
Kemet 408-986-0424 www.kemet.com
LED CURRENT (mA)
0
70
75
85
15
3465A F04b
65
60
510 20
55
50
80
EFFICIENCY (%)
MURATA LQH32CN220
TAIYO YUDEN LB2012B220M
TAIYO YUDEN CB2012B220
V
IN
= 3.6V
4 LEDs
Figure 4a. Efficiency Comparison of Different Inductors (LT3465)
Figure 4b. Efficiency Comparison of Different Inductors (LT3465A)