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AS1330

Datasheet - A p p l i c a t i o n I n f o r m a t i o n

Component Selection

Only three power components are required to complete the design of the boost converter, except the additional two resistors for the voltage

external ceramic capacitors.

Inductor Selection

The inductor should have low ESR to reduce the I²R power losses, and must be able to handle the peak inductor current without saturating.

High-frequency ferrite core inductor materials reduce frequency dependent power losses compared to less expensive powdered iron types,

which result in improved converter efficiency.

A 1 H inductor with a >850mA current rating and low DCR is recommended. For applications where radiated noise is a concern, a toroidal or

shielded inductor can be used.

Capacitor Selection

A 4.7 F capacitor is recommended for C1 and for C2. Small-sized ceramic capacitors are recommended. X5R and X7R ceramic capacitors are

recommended as they retain capacitance over wide ranges of voltages and temperatures.

Output Capacitor Selection

ESR and are available in small footprints. Up to 10 F output capacitor is sufficient for most applications. Larger values up to 22 F may be used

to obtain extremely low output voltage ripple and improve transient response.

An additional phase lead capacitor may be required with output capacitors larger than 10 F to maintain acceptable phase margin. X5R and X7R

dielectric materials are recommended due to their ability to maintain capacitance over wide voltage and temperature ranges.

Input Capacitor Selection

Low ESR input capacitors reduce input switching noise and reduce the peak current drawn from the battery. Ceramic capacitors are

recommended for input decoupling and should be located as close to the device as is practical. A 4.7 F input capacitor is sufficient for most

applications. Larger values may be used without limitations.

Diode Selection

≤ 3.0V a it is optional, although using one will increase device efficiency by 2 to 3%. On one hand the

schottky diode reduces the overshoot on the output signal but on the other hand the output disconnect function is no longer working.

Note:

Do not use ordinary rectifier diodes, since the slow recovery times will compromise efficiency.

Table 4. Recommended External Components

Name

Part Number

Value

Rating

Type

Size

Manufacturer

C1, C2

GRM219R60J106KE19

10 F

6.3V

X5R

0805

Murata

www.murata.com

GRM188R60J475KE19

4.7 F

6.3V

X5R

0603

L1

LQH32PN1R0NN0

1 H

2.05A

45m

Ω

3.2x2.5x1.55mm

LQH32PNR47NN0

470nH

2.55A

30m

Ω

3.2x2.5x1.55mm

EPL2010-102ML

1 H

1.35A

99m

Ω

2.0x2.0x1.0mm

Coilcraft

www.coilcraft.com

EPL2010-821ML

820nH

1.6A

68m

Ω

2.0x2.0x1.0mm

EPL2010-471ML

470nH

2.2A

40m

Ω

2.0x2.0x1.0mm