ltc3459es6-trpbf Linear Technology Corporation, ltc3459es6-trpbf Datasheet - Page 8

• Manufacturer Part Number: ltc3459es6-trpbf
• Description: 10v Micropower Synchronous Boost Converter In Thinsot
• Manufacturer: Linear Technology Corporation

OPERATION
LTC3459
This is accomplished by varying the t
proximately 1/(V
and a 0.6μA bias current in the timer, the t
more accurately predicted as follows:
APPLICATIONS INFORMATION
Inductor Selection
An inductor with a minimum value of 15μH is recommended
for use with the LTC3459. Values larger than 15μH will
result in lower ripple current and switching frequency.
High frequency ferrite core materials are strongly recom-
mended. Some inductors meeting these requirements are
listed in Table 1.
Table 1. Example Inductors
VENDOR/PART
Chip Inductors
Murata
LQH31C
LQH32C-Low Profi le
Taiyo Yuden
LB2016
Toko
LLB2520
Coilcraft
DO3314
DO1606T
Sumida
CMD4D06
CDRJ2D1BLD
8
(μH)
22
22
15
22
33
15
22
33
15
22
15
22
33
15
22
33
15
22
33
L
OUT
I
0.175/350
0.255/300
DCR (Ω)/
0.86/650
0.74/450
0.37/240
MAX
– V
0.7/250
0.7/130
1.7/180
2.5/160
3.8/130
1.2/500
0.4/700
0.5/500
0.5/400
0.8/300
1.3/240
1.7/85
3/160
1/105
(mA)
IN
). Due to propagation delays
3.2 × 1.6 × 1.8
3.2 × 2.5 × 1.6
2.0 × 1.6 × 1.6
2.5 × 2.0 × 1.6
3.3 × 3.3 × 1.4
6.5 × 5.3 × 2.0
6.6 × 5.8 × 0.8
3.2 × 3.2 × 2.0
DIMENSIONS
(mm)
OFF
OFF
www.murata.com
www.coilcraft.com
www.t-yuden.com
www.tokoam.com
www.sumida.com
period by ap-
[phone]
[phone]
[phone]
[phone]
INFORMATION
time can be
CONTACT
If V
mately 750ns.
Capacitor Selection
The boost converter requires two capacitors. The input
capacitor should be an X5R type of at least 1.0μF . The V
capacitor should also be an X5R type between 2.2μF and
10μF . A larger capacitor should be used if lower peak-to-
peak output ripple and better line regulation is desired.
Table 2. Capacitor Vendor Information
SUPPLIER
AVX
Murata
Taiyo Yuden
TDK
PCB Layout Guidelines
The high speed operation of the LTC3459 demands care-
ful attention to board layout. You will not get advertised
performance with a careless layout. Figure 4 shows the
recommended component placement for the TSOT ver-
sion of the part. A large ground pin copper area will help
to lower the chip temperature.
V
t
OUT
IN
OFF
is less than V
≈
100
Figure 4. Recommended Component
Placement for a Single-Layer Board
ns
+
0 6
1
2
3
[phone]
[phone]
[phone]
[phone]
.
IN
0 8
SW
GND
FB
μ +
, the t
PHONE
.
A
SHDN
3459 F04
V
pF
OUT
V
IN
V
OFF
V
• .
OUT
OUT
6
5
4
1 25
500
delay is fi xed at approxi-
–
RECOMMENDED COMPONENT
PLACEMENT. TRACES CARRYING
CURRENT ARE DIRECT. TRACE
AREA AT FB PIN IS SMALL. LEAD
LENGTH TO BATTERY IS SHORT
V
k
V
www.component.tdk.com
SHDN
IN
www.avxcorp.com
www.t-yuden.com
www.murata.com
WEBSITE
3459fa
OUT