ltc3525esc6-5-trpbf Linear Technology Corporation, ltc3525esc6-5-trpbf Datasheet - Page 10

• Manufacturer Part Number: ltc3525esc6-5-trpbf
• Description: 400ma Micropower Synchronous Step-up Dc/dc Converter With Output Disconnect
• Manufacturer: Linear Technology Corporation

OPERATIO
LTC3525-3/
LTC3525-3.3/LTC3525-5
Component Selection
Inductor values between 4.7µH and 15µH are recom-
mended. In most applications 10µH will yield the best
compromise between size and effi ciency. The inductor
should be a low-loss ferrite design and must be rated for
peak currents of at least 400mA without saturating. Induc-
tors with lower DC resistance will improve effi ciency. Note
that the inductor value does not have a signifi cant effect
on ripple current, so while lower values will increase the
operating frequency, they do not reduce output voltage
ripple.
Some recommended inductor examples are Murata
LQH32C and Coilcraft LPO4812, LPO3310, DO3314,
DS1608 and MSS4020.
10
Table 1. Inductor Vendor Information
SUPPLIER
Murata
Coilcraft
Sumida
Table 2. Capacitor Vendor Information
SUPPLIER
Murata
Taiyo Yuden
TDK
AVX
U
PHONE
USA: [phone]
[phone]
USA: [phone]
PHONE
USA: [phone]
[phone]
[phone]
[phone]
SHDN
V
IN
Figure 2. Recommended Component Placement
FAX
USA: [phone]
[phone]
USA: [phone]
FAX
USA: [phone]
[phone]
[phone]
[phone]
SHDN
GND
V
IN
LTC3525
A ceramic input bypass capacitor should be located as
close as possible to the V
minimum value of 1µF is recommended. If the battery is
more than a few inches away, a bulk tantalum decoupling
cap of at least 10µF is recommended on V
The output capacitor should also be a ceramic, located close
to the V
recommended. Increasing the value of the output capacitor
to 22µF will result in lower output ripple. Higher capacitor
values will only offer a small reduction in output ripple,
while reducing light load effi ciency by causing the peak
inductor current to increase above its minimum value of
150mA. The input and output capacitors should be X5R
or X7R types, not Y5V.
V
GND
OUT
SW
OUT
and GND pins. A minimum value of 10µF is
3525 F02
WEBSITE
www.murata.com
www.coilcraft.com
www.sumida.com
WEBSITE
www.murata.com
www.t-yuden.com
www.component.tdk.com
www.avxcorp.com
V
OUT
IN
and GND pins of the IC. A
IN
.
3525fa