AS1322 datasheet(13/18 Pages) AMSCO

13 / 18 page

www.ams.com/DC-DC_Step-Up/AS1322

Revision 1.10

13 - 18

AS1322

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

Figure 22. Efficiency Comparison of Different Inductors, VIN = 1.5V, VOUT = 3.3V

9.2.2

Output Capacitor Selection

Low ESR capacitors should be used to minimize VOUT ripple. Multi-layer ceramic capacitors are recommended since they have extremely low

ESR and are available in small footprints. A 2.2 to 10µF output capacitor is sufficient for most applications. Larger values up to 22µF 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 10µF 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 4.7µF input capacitor

is sufficient for most applications. Larger values may be used without limitations.

Diode Selection. A Schottky diode should be used to carry the output current for the time it takes the PMOS synchronous rectifier to switch

on. For VOUT < 4.5V a Schottky diode is optional, although using one will increase device efficiency by 2 to 3%.

Note:

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

Table 6. Recommended Output Capacitor

Part Number

TC Code

Rated Voltage

Dimensions (L/W/T)

Manufacturer

JMK212BJ226MG-T

22µF ±20%

X5R

6.3V

2x1.3x1.3mm

Taiyo Yuden

www.t-yuden.com

Table 7. Recommended Input Capacitor

Part Number

TC Code

Rated Voltage

Dimensions (L/W/T)

Manufacturer

GRM31CR70J106KA01L

10µF ±10%

X7R

6.3V

3.2x1.6x1.6mm

Murata

www.murata.com

100

Output Current (mA)

10uH - Coi l cr af t (M OS6020-103M L)

10uH - Sumi da(CDRH4D18-100)

6. 8uH - Sumi da(CDRH4D18-6R8)

6. 8uH - Sumi da(CR43-6R8)

4. 7uH - Coi l cr af t (M OS6020-472M L)

4. 7 uH - Sumi da(CDRH4D18-4R7)

3. 3 uH - Coi l cr af t (M OS6020-332M L)

Ser i es 8

0.1

Output Current (mA)

10uH - C oi l c r af t (M OS6020-103M L)

10uH - Sumi da(CD RH 4D18-100)

6. 8uH - Sumi da(C D RH 4D18-6R 8)

6. 8uH - Sumi da(C R 43-6R8)

4. 7uH - Coi l c r af t (M OS6020-472M L)

4. 7 uH - Sumi da(CD RH 4D 18-4R7)

3. 3 uH - C oi l c r af t (M OS6020-332M L)

AS1322 数据表(PDF) 13 Page - ams AG

AS1322 数据表(HTML) 13 Page - ams AG

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

数据表下载