DIO60120

Version 1.3, Aug 2025

www.dioo.com

© 2025 Dioo Microcircuits Co., Ltd. Jiangsu

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9.7. Input capacitor CIN

With the maximum load current at 2 A, the maximum ripple current through the input capacitor is about 1 A. A

typical X7R or better grade ceramic capacitor with 6 V rating and greater than 10 µF capacitance can handle this

ripple current well. To minimize the potential noise problem, place this ceramic capacitor really close to the IN

and GND pins. Carefully minimize the loop area formed by CIN, and IN/GND pins.

9.8. Output capacitor COUT

The output capacitor is selected to handle the output ripple noise requirements. Both steady-state ripple and

transient requirements must be taken into consideration when selecting this capacitor. For the best performance,

use X5R or a better grade ceramic capacitor with 6 V rating and greater than 10 µF capacitance.

9.9. Output inductor L1

There are several considerations in choosing this inductor.

(1) Choose the inductance to provide the desired ripple current. Choose the ripple current to be approximately

40% of the maximum output current. The inductance is calculated from Equation (2).

40%

I

f

)

/V

V

-

(1

V

L1

MAX

OUT,

SW

MAX

IN,

OUT

OUT









(2)

where fSW is the switching frequency and IOUT,MAX is the maximum load current. The DIO60120 regulator IC is

quite tolerant of different ripple current amplitudes. Consequently, the final choice of inductance can be slightly

off the calculation value without significantly impacting the performance.

(2) The saturation current rating of the inductor must be greater than the peak inductor current under full load

conditions.

L1

f

2

)

/V

V

-

(1

V

I

I

SW

MAX

IN,

OUT

OUT

MAX

OUT,

MIN

SAT,











(3)

(3) The DC resistance (DCR) of the inductor and the core loss at the switching frequency must be low enough

to achieve the desired efficiency requirement. Choose an inductor with a DCR lower than 50 mΩ to achieve a

good overall efficiency.

9.10. Load transient considerations

The DIO60120 regulator IC integrates the compensation components to achieve good stability and fast transient

responses. In some applications, recommend using a 22 pF ceramic capacitor in parallel with R1 may further

speed up the load transient responses and is thus recommended for applications with large load transient step

requirements.