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AS1346-49

Datasheet - Application Information

9 Application Information

9.1 Component Selection

Only three power components are required to complete the design of the buck converter. For the adjustable LBI two external resistors are

needed.

9.2 Inductor Selection

For the external inductor, a 3.3μH inductor is recommended. Minimum inductor size is dependant on the desired efficiency and output current.

Inductors with low core losses and small DCR at 2MHz are recommended.

9.3 Capacitor Selection

retain capacitance over wide ranges of voltages and temperatures.

9.3.1 Input and Output Capacitor Selection

Low ESR input capacitors reduce input switching noise and reduce the peak current drawn from the battery. Also low ESR capacitors should be

footprints.

For input decoupling the ceramic capacitor should be located as close to the device as practical. A 22μF input capacitor is sufficient for most

applications. Larger values may be used without limitations.

A 2.2μF to 10μF output ceramic 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.

Table 5. Recommended Inductor

L

DCR

Current Rating

3.3μH

m

Table 6. Recommended Input and Output Capacitor

C

TC Code

Rated Voltage

10 - 47μF

X5R

6.3V

X7R

25V

(EQ 2)





+

07





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